Randomness in Evolution: Valid and Invalid Usage

[mijopaalmc]

zosima-

It is very easy to accuse someone of making things up when you in fact don't understand the topic. So I would appreciate you telling me where you feel I have made things up so that I can explain to you the sources of my knowledge.

[zosima]

Look mijo, I don't want to argue with you about whether or not you answered the questions. You said some things that were really quite unclear and I asked you for clarifications several times. That was my attempt to understand, I can't read your mind, so if you don't answer my questions directly, it is very difficult to communicate. If you don't explain why you say things, I assume they're false.

It seems you claimed that that the use of the word "random" in evolutionary biology is somehow inconsistent with the use of statistics to prove their hypotheses. I wanted to understand your claim. Telling me that evolutionary biologists compare statistical experimental data to the null hypothesis does not tell me anything about how you have inferred an inconsistency. It is just a definition of one of many statistical techniques used in many sciences. So at best this is a very oblique, inadequate answer to my question. But a more pragmatic and realistic assessment is that you chose not to answer and instead chose to recite a definition. This makes suspicious that your original statement lacked merit. To put in terms that are more apropos to the subject matter: In absence of any evidence to the contrary, I'm forced to believe the null hypothesis about your credibility with respect to the statements I queried upon and am tempted to generalize to all your statements.

So I'll ask it again, what did you mean by this?
The problem is that statistical hypothesis testing (even in maximum parsimony methods, especially when the number of taxa is above 8) used in evolutionary biology has a much wider usage of random that the aforementioned one, and it is therefore inconsistent to state that evolution by natural selection is non-random while making the assumptions of randomness necessary to perform any number of statistical hypothesis tests.
and this:

I disagree I agree that using the definition of "random" as "equiprobable" is consistent with all the statistical assumptions that evolutionary biologists make to demonstrate evolution.

Note the bolded text. See the ambiguity?

My second question, also unanswered. Lets say we have a system where we are quite certain about the details that we care about on a given level of description, but are not certain about details on subordinate levels of description. Do you understand how some people might find calling this system random a little bit misleading?

For example. I can say with a high degree of certainty that my cat is on my lap. Am I 100% certain of my cat's position? No. Am I aware of what the internal components of my cat are doing? No. Is it misleading to say my cat's position is random? I would say yes. Do you agree? Do you understand why I think this? Do you see how this applies to the subject matter?

I was just trying to assess if you understand where everyone else on this thread is coming from or if you genuinely are confused by why we are so insistent that calling evolution random is, at best, misleading. If you don't understand I see a reason to continue, if not I'd be happy to stop. I'm not trying to trick you. I'm just trying to assess whether it is beneficial to continue.

Also,
Mijo, forcing me to ask a question four times just to get a response is asinine and frustrating. Then you claim that because I'm trying to make an attempt to understand what you are saying, I must not understand the subject matter. That is unreasonable. I was trying to communicate to; be polite, but don't try to imply I don't understand statistics, Mijo. Remember just 3 pages ago you demonstrated a complete ignorance as to how certainty applies to probability and the differences between a finite set, a countably infinite set, and an uncountably infinite set. To say that I'm going out on a limb to be nice,to respect your position regardless of how well you understand the subject matter, is an incredibly generous understatement. So please, lets not play the who knows what game. I would just appreciate it, if you could directly answer my questions. I promise Mijo these aren't trick questions. You only make yourself look either silly or paranoid when you dance around them.

[zosima]

In lieu of any response, again, I think we can consider this thread over. Mijo's last minute assertions about evolutionary biologists misusing their statistics are conceded as completely without basis in evidence or reason.

[mijopaalmc]

zosima-

I'm just a little baffled about how you could not understand that statistics are based on probability distributions of samples statistics.

Have you taken a basic statistics course?

[mijopaalmc]

Heres' the deal:

The point of inferential statistics is to make a statement of about a descriptor of a population without having to measure said descriptor for every individual in the population. In other word, inferential statistics strive to describe an unmeasured parameter of the population using a measure statistic of the sample. Now, regardless of the specific statistical test chosen, that sample statistic thus calculated follows its own probability distribution, giving one a probability of finding data that is as extreme as or more extreme than than the observed data purely by chance. Now, this entire process depends on the fact that the statistic calculated from the sample data is in fact a random variable and can take on many values depending on certain characteristics of the the data, which in turn requires a broader definition of "random" than "equiprobable".

[jimbob]

Is there agreement that if the environment is stable, then there will be adaptation to that environment?

My contention is that some of the forms of adaptation that take place will be random, and these will close up certain avenues, and open others.

On an aside about to Zosima's statement about the eye.

As far as I can think of, arthropods alone have evolved at least three different types of "advanced" eye:

The lobster eye (collimators, which is the approach used for X-ray optics BTW).

The insect compound eye

The spider eye(s) which I think are simple eyes with lenses

Then there are the mollusc eyes (the scallop being a bivalve must have evolved its vision system seperatelyto the cephalopods)

The point being that all these variants "solve" similar problems, but the solution is effected by completely different means.

ETA.

I would consider it valid to talk about the separate evolution of the eye as either random or (almost) inevitable, depending on the level of detail. that there are eyes is very likely; what form this eye will take in any particular organism is dependent on which set of utations occuced first, and which initial direction the evolution took.

[zosima]

zosima-

I'm just a little baffled about how you could not understand that statistics are based on probability distributions of samples statistics.

Have you taken a basic statistics course?

I have taken courses in statistics as well as higher math. But remember we decided to drop the ad hominems about who knows want because we don't want you to be embarrassed. All I would ask is that you make your point clearly, there is no reason to be incredulous about people's inability to understand you. I've asked several times what you mean.

Whats really frustrating, is that I ask a question nicely, and you refuse to answer, I wait for a while, you ignore it. You won't just answer a question, I knew that if I added that little post afterwards stating the issue was closed that I could get you to come back and answer. You really are quite predictable.

So thanks for finally getting around to answering my question. Let me summarize your argument. Evolution is modeled using random variables. The term 'random variable' has the word random in its name. Thus evolutionary biologist are wrong to call evolution non-random. I think its pretty easy to see the flaw in this argument. The technique of using random variables to model our imperfect knowledge of a process doesn't say anything about the process itself. For example in the Monty Hall problem we use random variables to describe the probability of winning, but the actual process is predetermined. Nothing changes because of the way we model it. It seems obvious to me that there is a difference between a random variable and a random process. Evolution as a science uses the former, evolution is not the latter. We're done.

On eyes:

I would consider it valid to talk about the separate evolution of the eye as either random or (almost) inevitable, depending on the level of detail. that there are eyes is very likely; what form this eye will take in any particular organism is dependent on which set of utations occuced first, and which initial direction the evolution took.

Man, I was hoping this thing was over. I'm worried that if I respond, this thing will blow up again. But here it is.

I see what you're saying, but characterizing evolution as reaching a point where its like "heads: compound eye, tails: vertebrate eye" is a little off base. There are two separate issues. One different types of eyes are better suited for different conditions. Two, once an eye shows up it is conserved. So after evolving they may be modified by evolution to suit purpose that would actually better served by the eye available in another taxonomic branch.

Looking at arthropods:
At some point the originator of the arthropods developed photoreceptors. The environment pushed it towards a compound eye. The reason it went this way probably had to do with balancing all sorts of different constraints, developmental architecture, effective sensation, minimal energy requirements. Once it showed up it stayed. One type of spider eye and the lobster eye developed from the compound eye. The other type of spider eye is a pretty basic photoreceptor. I have no idea why spiders at one point in their evolution required two types of eyes, but apparently they did.

We can see how these different solutions today suit different purposes. Spiders catch their prey without site and only really need vestigial eyes. Lobsters need to be able to see in very low light environments so they developed the reflective eyes that maximize their capacity to see in low light conditions. The compound eyes have a huge amount of redundancy. If you look at many insects, it seems clear that producing many redundant copies seems to be their ecological niche.

The point though is that saying that it "really could have gone either way", is conflating the importance of trait conservation and the long history of a species, with randomness. At each point traits develop due to the pressures at that time and they accumulate over a long history. While each individual generation is subject to randomness, over a number of generations the law of large numbers applies and the path ends up going the same way, regardless.

If there are any points in evolution that are random, in the sense that things can go either way, they are few and far between

[jimbob]

I see what you're saying, but characterizing evolution as reaching a point where its like "heads: compound eye, tails: vertebrate eye" is a little off base. There are two separate issues. One different types of eyes are better suited for different conditions. Two, once an eye shows up it is conserved. So after evolving they may be modified by evolution to suit purpose that would actually better served by the eye available in another taxonomic branch.

{nitpick}
The eye is only conserved where there is a selective advantage. Loss of sight in lightless environments is also inevitible.

I also don't like the phrase "So after evolving they may be modified by evolution to suit purpose" Although I do sometimes use similar phrases. To me this implies that there is a "guided direction" to evolution that I would dispute. Evolutionary Algorithms in engineering are to a purpose, but evolution itself isn't.

I think it can hide a bit of the story.

Here is an example of what I mean:

"mammals evolved fur from modified scales to regulate temperature" or "fur evolved because modified scales with fur-like features gave a selective advantage of improved temperature regulation"...



{/nitpick}

I am also saying that there are also positive feedback loops: the physical/biochemical trait facilitates certain behavioural traits or lifestyles, which in turn modify the selective pressure. An animal with rudimentary sight might begin to use such sight for hunting/scavenging, one without this wont. There are a whole set of niches opened up by the presence of the light-sensitive cells.


I would disagree about the "rudimentary" spider sight:

Different versions seem very well adapted (http://www.amonline.net.au/spiders/toolkit/hairy/see.htm):

especially jumping spiders:

When hunting, the eyes of jumping spiders see in three different ways, using three different sets of eyes:

The spider first senses movement of distant prey with the side eyes (PLE), which provide a blurry wide-angle image.
Once movement is detected, the spider turns in that direction and locks onto the moving prey with the large, middle front eyes (AME). These eyes provide a clear, focussed telephoto image, probably in colour. The spider can track moving prey both by body movements and by using muscles to internally swivel the elongated eye capsules so that the light sensitive retina of each eye remains locked on the prey.
While the spider stalks closer, it uses the side front eyes (ALE) judge the distance to the prey. When it judges the prey to be close enough (about 2 - 3 cm), the spider leaps

There are several other types of vision system within arthropods.

And at least two different types of system within molluscs. For example the scallop has a "solution" that resembles a compound eye in function if not in form.

That adaption will occur is inevitable, what adaptions, and how; indeed, which niches are created and occupied are not.

If this wasn't the case then ecosystems would tend to look very similar once re-stabilizing after each extinction event. Now you could argue that this is the case to a certain extent, rhinos and triceretops are/were both large herbivores, but there are also significant differences. Only one could possibly have eaten grass. Indeed the emergence of grasses must have had a disruptive effect on the whole ecosystem. Ditto flowering plants.

Life got along without flowering plants for hundreds of millions of years, so I would consider that there must be a window of tens of millions of years when such plants could have emerged.

If you are more interested in the differences, then I guess you are more prone to talk about the random aspect, if you are more interested in the similarities, then the inevitible aspect is more interesting.

Completely denying one or the other is wrong. Being an engineer with a physics background, and dealing with highly probable but still random events also pushes me towards emphasising the random aspect.

[mijopaalmc]

I have taken courses in statistics as well as higher math. But remember we decided to drop the ad hominems about who knows want because we don't want you to be embarrassed. All I would ask is that you make your point clearly, there is no reason to be incredulous about people's inability to understand you. I've asked several times what you mean.

I have made my point clearly and you have ignored it. The practice of statistics is based on making inference about the relation between populations and sample or two or more different samples, which requires understanding that quantities calculated from a specific data set almost certainly will differ from quantities calculated from another data set even if it is taken from the same population. This therefore necessitates comprehending that making a statement about the data can only be done by considering how the sample statistic is distributed in a large number of similar experiments. That you seem not to think that the basis for the practice of statistics is somehow not important to how statistics are used implies a lack of knowledge about the subject. Simply stating this idea is not an ad hominem because it goes directly to the ability from true, valid, and sound argument about the the topic. In fact the questioning of knowledge and understanding is a tactic that has frequently been used against creationists on this board.

What makes it a valid strategy against creationism?

Whats really frustrating, is that I ask a question nicely, and you refuse to answer, I wait for a while, you ignore it. You won't just answer a question, I knew that if I added that little post afterwards stating the issue was closed that I could get you to come back and answer. You really are quite predictable.

I was actually checking to see if I could find evidence that the statement I made could be corroborated by the scholarly literature for all kinds of statistics (both parametric and nonparamentric), and indeed it can for a wide variety of statistics, for example:

the Anderson-Darling test (http://projecteuclid.org/DPubS/Repository/1.0/Disseminate?view=body&id=pdf_1&handle=euclid.aoms/1177729437)
the Friedman two-way analysis of variance (http://projecteuclid.org/DPubS/Repository/1.0/Disseminate?view=body&id=pdf_1&handle=euclid.aoms/1177731944)
Kendall's τ (http://projecteuclid.org/DPubS/Repository/1.0/Disseminate?view=body&id=pdf_1&handle=euclid.aoms/1177732186)
the Mann-Whitney U test (http://projecteuclid.org/DPubS/Repository/1.0/Disseminate?view=body&id=pdf_1&handle=euclid.aoms/1177730491)
the Wald-Wolfowitz runs test (http://projecteuclid.org/DPubS/Repository/1.0/Disseminate?view=body&id=pdf_1&handle=euclid.aoms/1177731909)


So thanks for finally getting around to answering my question. Let me summarize your argument. Evolution is modeled using random variables. The term 'random variable' has the word random in its name. Thus evolutionary biologist are wrong to call evolution non-random. I think its pretty easy to see the flaw in this argument. The technique of using random variables to model our imperfect knowledge of a process doesn't say anything about the process itself. For example in the Monty Hall problem we use random variables to describe the probability of winning, but the actual process is predetermined. Nothing changes because of the way we model it. It seems obvious to me that there is a difference between a random variable and a random process. Evolution as a science uses the former, evolution is not the latter. We're done.

The above is a mischaracterization of my argument. Evolution by natural selection is random because it is possible, as Bennett and Lenski showed, to start with several nearly identical populations and expose them to identical environmental conditions and have them each experience a different change in fitness and, more importantly, a different trade-off in fitness.

Your analogy to the Monty Hall problem seems porrly formed, because the the probabilities in the Monty Hall problem are known to arise directly and solely from the contestant's lack of knowledge of the initial arrangement, while it is far from certain that the perceived randomness in evolution by natural selection arise solely from our lack of complete knowledge of the initial conditions.

[zosima]

{nitpick}
The eye is only conserved where there is a selective advantage. Loss of sight in lightless environments is also inevitible.

I also don't like the phrase "So after evolving they may be modified by evolution to suit purpose" Although I do sometimes use similar phrases. To me this implies that there is a "guided direction" to evolution that I would dispute. Evolutionary Algorithms in engineering are to a purpose, but evolution itself isn't.

I think it can hide a bit of the story.

Here is an example of what I mean:

"mammals evolved fur from modified scales to regulate temperature" or "fur evolved because modified scales with fur-like features gave a selective advantage of improved temperature regulation"...



{/nitpick}


Fair enough, Its easy to use language that implies design, but really stands in for a much more complicated phrase. I don't really like having to add the caveat every time I talk about evolution.


I am also saying that there are also positive feedback loops: the physical/biochemical trait facilitates certain behavioural traits or lifestyles, which in turn modify the selective pressure. An animal with rudimentary sight might begin to use such sight for hunting/scavenging, one without this wont. There are a whole set of niches opened up by the presence of the light-sensitive cells.


That adaption will occur is inevitable, what adaptions, and how; indeed, which niches are created and occupied are not.

If this wasn't the case then ecosystems would tend to look very similar once re-stabilizing after each extinction event. Now you could argue that this is the case to a certain extent, rhinos and triceretops are/were both large herbivores, but there are also significant differences. Only one could possibly have eaten grass. Indeed the emergence of grasses must have had a disruptive effect on the whole ecosystem. Ditto flowering plants.

Life got along without flowering plants for hundreds of millions of years, so I would consider that there must be a window of tens of millions of years when such plants could have emerged.


That adaptation opens new niche's is unpredictable and we might even say that it is 'fortunate',I agree, but I don't see how you can call that random. Ecological systems reach very stable equilibriums. When they are disrupted by things like extinction events, amongst other things, these equilibriums shift and evolution encourages adaptation.

For sure there are feedback loops, particularly on short time scales. But this too doesn't imply that anything is random.

The fact that they end up not being identical after an extinction event doesn't imply that this is due to a random component. It reflects the fact that different creatures with different histories and different conserved traits are adapting to same pressures. Really I've addressed it previously several times. If you took the same creatures and placed them into those niches twice, maybe there would be some minor differences, but overall they would look very similar. Actually the experimental evolution paper that was addressed earlier in the thread shows this.

I would agree evolution is unpredictable, chaotic, historically contingent, and complex. That doesn't mean random. If two systems follow the same rules to go from different starting points to different stopping places there is nothing random about it.


I would disagree about the "rudimentary" spider sight:

Different versions seem very well adapted (http://www.amonline.net.au/spiders/toolkit/hairy/see.htm):

especially jumping spiders:

There are several other types of vision system within arthropods.

And at least two different types of system within molluscs. For example the scallop has a "solution" that resembles a compound eye in function if not in form.

If you are more interested in the differences, then I guess you are more prone to talk about the random aspect, if you are more interested in the similarities, then the inevitible aspect is more interesting.

I wouldn't argue any species is il-adapted to its niche, thats almost impossible if you believe in evolution. But spiders rely on other senses do to what they do. Your article says "Spiders usually have eight eyes (some have 6 or fewer), but few have good eyesight. " But the fact that there are different eyes doesn't support any sort of random conclusion, unless you ignore historical contingency, trait conservation, and think that there are no trade-offs between different types of eyes.



Completely denying one or the other is wrong. Being an engineer with a physics background, and dealing with highly probable but still random events also pushes me towards emphasising the random aspect.
I think what most people on this thread, including myself, have been arguing that they aren't equally true. One way of thinking about it is a much better characterization than the alternative. That evolution, too, is a system of highly probable events. Where its not impossible that an alternative outcome occurs, but because we are talking about such long timescales so many individuals, so many mutations, that the probability that it works another way is vanishingly small. Thinking that it is somehow less reliable than these other systems, really doesn't do credit to the work that the scientists in the field are doing.

I'm not going to say that there haven't been events where the path of a species is determined by the outcome of some probabilistic event, just that its not bloody likely.

[zosima]

I have made my point clearly and you have ignored it. The practice of statistics is based on making inference about the relation between populations and sample or two or more different samples, which requires understanding that quantities calculated from a specific data set almost certainly will differ from quantities calculated from another data set even if it is taken from the same population. This therefore necessitates comprehending that making a statement about the data can only be done by considering how the sample statistic is distributed in a large number of similar experiments. That you seem not to think that the basis for the practice of statistics is somehow not important to how statistics are used implies a lack of knowledge about the subject. Simply stating this idea is not an ad hominem because it goes directly to the ability from true, valid, and sound argument about the the topic. In fact the questioning of knowledge and understanding is a tactic that has frequently been used against creationists on this board.

What makes it a valid strategy against creationism?
Your most recent ad-hominem was when you got baffled that I couldn't read your mind. No it isn't a valid strategy against creationism, though you are correct it is often applied. Lots of people make bad arguments on this forum that doesn't justify yours.



I was actually checking to see if I could find evidence that the statement I made could be corroborated by the scholarly literature for all kinds of statistics (both parametric and nonparamentric), and indeed it can for a wide variety of statistics, for example:

the Anderson-Darling test (http://projecteuclid.org/DPubS/Repository/1.0/Disseminate?view=body&id=pdf_1&handle=euclid.aoms/1177729437)
the Friedman two-way analysis of variance (http://projecteuclid.org/DPubS/Repository/1.0/Disseminate?view=body&id=pdf_1&handle=euclid.aoms/1177731944)
Kendall's τ (http://projecteuclid.org/DPubS/Repository/1.0/Disseminate?view=body&id=pdf_1&handle=euclid.aoms/1177732186)
the Mann-Whitney U test (http://projecteuclid.org/DPubS/Repository/1.0/Disseminate?view=body&id=pdf_1&handle=euclid.aoms/1177730491)
the Wald-Wolfowitz runs test (http://projecteuclid.org/DPubS/Repository/1.0/Disseminate?view=body&id=pdf_1&handle=euclid.aoms/1177731909)


You can link to statistics papers like the best of em. None of these papers show that there is anything inconsistent with modeling a system statistically and calling that system non-random. That is the claim you tried to make.
They certainly don't make the specific claim that you make about evolution. So just linking a bunch of esoteric papers on statistics proves nothing. Well I take that back, it does seem to suggest that your claim that you were searching the literature is less than credible. If you had been searching the literature I would expect that you would either find some evidence that actually supports your claim. I guess it could also suggest that no one supports your claims.

Either way, you need to explain how the paper:
"On a Test of Whether one of Two Random Variables is Stochastically Larger than the Other" supports anything that you are saying. Remember, Mijo, we can't read your mind. If I could do that, I'd have won Randi's prize. :D



The above is a mischaracterization of my argument. Evolution by natural selection is random because it is possible, as Bennett and Lenski showed, to start with several nearly identical populations and expose them to identical environmental conditions and have them each experience a different change in fitness and, more importantly, a different trade-off in fitness.


Its a mis-characterization of your original argument, but not of the claim that
"it is therefore inconsistent to state that evolution by natural selection is non-random while making the assumptions of randomness necessary to perform any number of statistical hypothesis tests" It rebuts that claim directly.
What you are doing by switching back to the Bennett and Lenski paper is called shifting your argument. You lose one, then say you were actually talking about something else. However, since I already skewered you on that topic, I'll just provide a link to that post, and you can re-read why neither, Bennett, Lenski, or myself agree with you.

This is why the Bennett and Lenski disagree:
http://forums.randi.org/showpost.php?p=3604464&postcount=448
This link is why your reanalysis of their paper is wrong:
http://forums.randi.org/showpost.php?p=3605728&postcount=471

If you're going to shift your argument, then please shift it to something we haven't talked about before, otherwise you're jumping out of the frying pan and into the fire.


Your analogy to the Monty Hall problem seems porrly formed, because the the probabilities in the Monty Hall problem are known to arise directly and solely from the contestant's lack of knowledge of the initial arrangement, while it is far from certain that the perceived randomness in evolution by natural selection arise solely from our lack of complete knowledge of the initial conditions.

That demonstrates my point exactly. The random variables model a system in the Monty Hall problem yet the system is still deterministic. When statistics are used in empirical sciences we have no a priori knowledge about whether the statistics are modeling our lack of complete knowledge or some fundamental randomness. Thus it is not inconsistent, to model a system using random variables but still claim the system is non-random.

As to whether "...it is far from certain that the perceived randomness in evolution by natural selection arise solely from our lack of complete knowledge of the initial conditions." That is exactly the subject we've been discussing and your retreat on every other front suggests that its outcome is more certain than you'd like to believe.

My example supports my point, I'm sorry it doesn't support your point, but the day I start using examples that support other peoples' claims is probably the day I need to take a break from JREF.

[articulett]

Zosima, both have insulted me too. I have taken advanced courses and both statistics and probabilities. No one but themselves imagines they have expertise on this topic at all. Those who understand the topic understand what the actual experts are saying and why the imagined experts are full of crap. Those who need to believe something or other may be fooled temporarily by the self-appointed pedants. The self-appointed pedants, however, cannot or will not cede a point. They must see themselves as smarter and righter than you and Dawkins and Gould and Coyne and Sol Invictus, and Cyborg and anyone and everyone who dares to point out their failure at communicating intelligibly.

In their heads they must be geniuses... the fact that no one else seems to follow them or agree matters not one wit. In their heads, all of us cannot follow them because we don't have enough education or something. Interesting cognitive dissonance. It appears that the only people they are able to communicate their understanding with is creationists, but hey-- who needs to communicate with scientists and others when you imagine you are smarter than them all-- you know--"divine knowledge" and all that.

Both of them switch tenses mid definition in order to define selection as "random"... they say that since you can't "predict" with 100 percent accuracy who will live or not... it's "random" or "probabalistic"... which means "random" to mijo or them.

I was a genetic counselor. They are full of crap. Nobody but creationists are as obfuscating on the topic as they are. I'm not saying they ARE creationists... but they ought to consider employment at the Discovery Institute given their talents at failing to convey understanding of natural selection and their endless need to tell everyone that it somehow makes sense to call evolution "random".

[mijopaalmc]

zosima-

You're main problem is that you seem to see convergent behavior as evidence of of non-randomness. Unfortunately, such an approach would make everything non-random, because even systems that we can all agree are random (e.g., radioactive decay) can have orderly results (e.g., the functioning of an ionization smoke detector). The idea with evolution by natural selection is that, as demonstrated in the Bennett and Lenski paper (which you misinterpreted and continue to misinterpret), the constituent processes of evolution by natural selection, mutation and natural selection, is random but the results of the process, the adaptive optimization of an organism to its environment, are not.

I will deal with your other points within the next three hours, but thought that it was necessary to explain the fundamental objections I have to your approach immediately.

[Walter Wayne]

That adaptation opens new niche's is unpredictable and we might even say that it is 'fortunate',I agree, but I don't see how you can call that random. Ecological systems reach very stable equilibriums. When they are disrupted by things like extinction events, amongst other things, these equilibriums shift and evolution encourages adaptation.

I've addressed it previously several times. If you took the same creatures and placed them into those niches twice, maybe there would be some minor differences, but overall they would look very similar. Actually the experimental evolution paper that was addressed earlier in the thread shows this.
Well, I think the main difference you and I have, is the scale to view evolution on.

Those minor difference you mention may seem negligible, but they are base material used when the next shift in environment happens. As a result differences accumulate through subsequent events.

It seems odd to me to look at the short term evolution, when the principle point of attack is so called "macro"-evolution. That is, how it acts over the long term.
I would agree evolution is unpredictable, chaotic, historically contingent, and complex. That doesn't mean random. If two systems follow the same rules to go from different starting points to different stopping places there is nothing random about it.
Well, the question is what happens from the same starting point if we care principly about the technical randomness. However, for practical purposes if the system is so complex that evolution is unpredictable and chaotic then even if it were technically determistic, it would be random in the practical sense.

When classical physics "ruled" the universe, scientist thought coin flipping and die rolls were ultimately determistic, but it didn't stop them being used as practical devices for generating "random" results in a determistic universe.

In the end though, it looks like we agree on most things except the scale we are talking about.

Walt

[Walter Wayne]

zosima-

You're main problem is that you seem to see convergent behavior as evidence of of non-randomness. Unfortunately, such an approach would make everything non-random, because even systems that we can all agree are random (e.g., radioactive decay) can have orderly results (e.g., the functioning of an ionization smoke detector).
I have to disagree with you that it makes all systems we ce agree on as random, non-random.

A photon travelling through space or some sort of waveguide will yield an unpredictable result at the opposite end. That system is both technically random, and random in the practical sense. If I send a bazillion photons through the same setup, the results will match the prediction of classical physics. Sure there is a noise term, but for any practical purpose 10 Watts +/- a few attoWatts is predictable. The system is technically random, but in a practical sense it is non-random, just like your fire detector.

What I do agree with you on is that convergence is not evidence of non-randomness. Once you have heredity in a system, it is possible for it to converge, but when repeated see it converge to a different point.

Walt

[zosima]

@Articulett
True 'dat. I was trying to see if we could come to some agreement and was just curious about some things that were said, but apparently asking why he claimed evolutionary biologists don't know how to use statistics is evidence of my ignorance. It really is a pain to try to remain polite with someone like Mijo.


zosima-

You're main problem is that you seem to see convergent behavior as evidence of of non-randomness. Unfortunately, such an approach would make everything non-random, because even systems that we can all agree are random (e.g., radioactive decay) can have orderly results (e.g., the functioning of an ionization smoke detector). The idea with evolution by natural selection is that, as demonstrated in the Bennett and Lenski paper (which you misinterpreted and continue to misinterpret), the constituent processes of evolution by natural selection, mutation and natural selection, is random but the results of the process, the adaptive optimization of an organism to its environment, are not.

I will deal with your other points within the next three hours, but thought that it was necessary to explain the fundamental objections I have to your approach immediately.

Thanks for telling me what "my main problem" is. But thats whole point. No one agrees that a smoke detector is a random system because if it were, we wouldn't use it save our lives. It is a non-random device that has some random components.

As to Bennett and Lenski, you can assert that I misinterpret their results, but Bennet, Lenski, and I disagree. You never addressed my refutation of your arguments in the first place and you still haven't. So until you look at those, there is no reason why anyone should believe your blind assertions. But one thing I will say, convergent behavior only strengthens the conclusion that evolution is non-random, but it would still be non-random in its absence. It is superlative evidence, not necessary evidence.

I'm not sure how you come to the conclusion that my definition of well...my definition of something makes everything non-random. Other than maybe the fact that you've defined all events as random, so it seemed like a good strategy to invert the statement.

Also, don't bother getting to my other arguments. I wanted to understand why you claimed that evolutionary biologists are not understanding the assumptions of their statistics or how you could claim that they're being inconsistent. You've shifted to something else, something that is already plenty well discussed. The Bennett Lenski argument is long since over. You lost. And you don't get a redo. So rather than talk about this topic again. And make the same arguments again. Lets just leave it be.

@Walter Wayne,

When I said minor, it probably would have been better to say inconsequential. They're minor deviations in a path but it goes to the same place either way. For example, a mutation might show up in individual 4 instead of individual 7, different individuals, but if the mutation is beneficial it spreads exponentially. Maybe the same amino acid gets coded using a different equivalent sequence. Those changes don't aggregate, they cancel.

I would agree that there is a lot of practical randomness. We use probability all the time to describe our limited knowledge, but its often that people conflate that with true randomness. The major point people are arguing for here is that the more scientists study evolution the more regular its processes appear. The more evolution looks like it follows a set of laws, rules, and regulations, just like other sciences, and that amongst other things suggesting otherwise tends to do their work a discredit.

I'm totally willing to agree to disagree on the level at which things become non-random. I really just wanted to figure out what Mijo meant about the inconsistency and not blow this whole thing up again.

[mijopaalmc]

Thanks for telling me what "my main problem" is. But thats whole point. No one agrees that a smoke detector is a random system because if it were, we wouldn't use it save our lives. It is a non-random device that has some random components.

You are missing the point entirely. The processes of evolution, mutation and natural selection, are random while the result of evolution, adaptive optimization to the environment, is not. Similarly, the process that make an ionization smoke detector work, radioactive decay, is random, the result, the actual functioning of the detector is not.

As to Bennett and Lenski, you can assert that I misinterpret their results, but Bennet, Lenski, and I disagree. You never addressed my refutation of your arguments in the first place and you still haven't. So until you look at those, there is no reason why anyone should believe your blind assertions. But one thing I will say, convergent behavior only strengthens the conclusion that evolution is non-random, but it would still be non-random in its absence. It is superlative evidence, not necessary evidence.

No, convergence does not strengthen your case that evolution by natural selection is non-random. The observation convergence happens whether or not the underlying processes are random; otherwise the functioning of an ionizing smoke detector would prove that radioactive decay was non-random, which contradicts most of quantum mechanics.

I'm not sure how you come to the conclusion that my definition of well...my definition of something makes everything non-random. Other than maybe the fact that you've defined all events as random, so it seemed like a good strategy to invert the statement.

The insistence that convergence make a system non-random is what I was referring to, and, as mentioned above convergence does not imply that the underlying mechanism is non-random.

[jimbob]

zosima,

Even though extinction events are rare, they have been instrumental in determing the course of evolution on this planet. I am also not sure about the long-term stability of ecosytems either. We are only about 10,000 years from the end of the last Ice Age, where environments were significantly different.

Earlier than that, it seems that the Toba eruption (http://en.wikipedia.org/wiki/Toba_catastrophe_theory) 70,000 years ago reduced the human population dramatically (figures of between 1,000 and 10,000 breeding pairs). A quick google search suggests that this level of poplulation would qualify for "endangered species" status. Obviously humanity survived that event, but with population levels as low as that, chance begins to become more significant.

Two significant events within 100,000 years seems like quite a high rate to me, but again it depends on whether you are interested in the similarities or the differences.

If you are talking about the evolution of humanity, which is what many people are most interested in, then random (selective) factors have been very important. This would also be the case for virtually any other particular species.

Once the hominids had begun to emerge, there might have been an inevitibility about the emergence of something akin to humanity. However I would contend that this emergence and the "opening" of the niche was a result of the environment interacting with appropriate precursor animals at the right time, and with the right traits.

Something was going to evolve, and whatever did evolve, it would have shown amazing levels of adaptation to the environment, and modulated the slective environment for other organisms. Just because humanity evolved, doesn't mean that anything special happened.

[Belz...]

The above is a mischaracterization of my argument. Evolution by natural selection is random because it is possible, as Bennett and Lenski showed, to start with several nearly identical populations and expose them to identical environmental conditions and have them each experience a different change in fitness and, more importantly, a different trade-off in fitness.

"Nearly" identical ?

You are missing the point entirely. The processes of evolution, mutation and natural selection, are random while the result of evolution, adaptive optimization to the environment, is not.

That's a very nice way to weasel out of the admission that you were wrong. How is "adaptive optimisation" NOT part of the process ?

[Belz...]

No, convergence does not strengthen your case that evolution by natural selection is non-random.

How in the blue hell can you say that ? What's causing the convergence, then ?

[zosima]

You are missing the point entirely. The processes of evolution, mutation and natural selection, are random while the result of evolution, adaptive optimization to the environment, is not. Similarly, the process that make an ionization smoke detector work, radioactive decay, is random, the result, the actual functioning of the detector is not.

As I said in my previous post, we already went over this. I just wanted to clarify what you were saying about use of statistics. With the definition you're supporting now, evolution is non-random just as a smoke detector is non-random. There are definitely random components to evolution on the small scale, but just like the smoke detector they smooth out on big scales. So we're completely in agreement. I'll even admit the likelihood of selection of an individual is probabilistic in some cases, but once you get up to a very modest number of individuals that is not the case.


No, convergence does not strengthen your case that evolution by natural selection is non-random. The observation convergence happens whether or not the underlying processes are random; otherwise the functioning of an ionizing smoke detector would prove that radioactive decay was non-random, which contradicts most of quantum mechanics.

The insistence that convergence make a system non-random is what I was referring to, and, as mentioned above convergence does not imply that the underlying mechanism is non-random.

Well, as Belz noted you seem to be shifting your argument, but I'll definitely admit convergence doesn't prove that the components of a system are non-probabilistic. If you thought I meant that it did,then I'm sorry I didn't spell it out in greater clarity. But as I mentioned above, convergence is purely superlative. It strengthens the case that evolution has clearly defined rules and tendencies, that at evolutionary scales details smooth out. Also, if you feel like you were saying this the whole time, then I apologize for the misunderstanding. As I've mentioned above, it can be quite difficult, nigh impossible, to read your mind.


Even though extinction events are rare, they have been instrumental in determining the course of evolution on this planet. I am also not sure about the long-term stability of ecosytems either. We are only about 10,000 years from the end of the last Ice Age, where environments were significantly different.

Well I wouldn't really call things like ice-ages and volcanic eruptions random. I mean a glacier or volcano is about as random as a mac truck. That said I fully agree that they represent important historical contingencies, noise in the system that is crucial for making the species on this planet what they were and are. Without them, things would definitely be different.

Also, I think the speed with which traits spread through a population is often underestimated, so its easy to imagine that things are more 'random' than they really are. The spread of a trait actually follows an exponential function so in a very small number of generations everyone in a population that randomly interbreeds should have a beneficial trait(or at least the population should be at Hardy-Weinberg equilibrium). I showed(roughly) in another thread that if a trait that doubled an individual's rate of reproduction, if it showed up at a rate of one in one million, and if the population had a stable 10 billion individuals, that the trait would be in every individual after only 17 generations. And humans actually have relatively long generations, the generations of insects or bacteria are so short that a beneficial trait could spread to all in months or years. (You may quibble about the numbers, but the function itself will always be exponential in form)


Earlier than that, it seems that the Toba eruption 70,000 years ago reduced the human population dramatically (figures of between 1,000 and 10,000 breeding pairs). A quick google search suggests that this level of poplulation would qualify for "endangered species" status. Obviously humanity survived that event, but with population levels as low as that, chance begins to become more significant.

Two significant events within 100,000 years seems like quite a high rate to me, but again it depends on whether you are interested in the similarities or the differences.
I think that would definitely increase the probability that a random event could affect the course of a species, but its still not very likely. Even 1,000 individuals is enough that any statistical survival of an individual would translate into a predictable fraction of the 1000 individuals surviving some evolutionary pressure.

Now there is a question of whether the Toba event actually randomly culled certain segments of the population. I don't know for sure, I'm not really familiar with Toba, but from what I read online its effects were pretty predictable. It killed all other human species, with the exception of H.sapiens and H. neanderthalensis
Selectively, specifically, killing certain sub-populations that lack adaptive traits isn't random.


If you are talking about the evolution of humanity, which is what many people are most interested in, then random (selective) factors have been very important. This would also be the case for virtually any other particular species.

Once the hominids had begun to emerge, there might have been an inevitibility about the emergence of something akin to humanity. However I would contend that this emergence and the "opening" of the niche was a result of the environment interacting with appropriate precursor animals at the right time, and with the right traits.

Something was going to evolve, and whatever did evolve, it would have shown amazing levels of adaptation to the environment, and modulated the slective environment for other organisms. Just because humanity evolved, doesn't mean that anything special happened.

I'm not trying to say that humans or any intelligent species must necessarily evolve. I'm not trying to say that there is anything special about human existence. If the KT event had not happened, we probably wouldn't be here, or at least, not in the way that we are. But I think its a mistake to call events like that random. You're talking about 1000s of tons of rock moving with the inevitability of huge inertia, huge momentum. If you ask me, thats about as non-random as you can get.

[jimbob]

except that the survival must also be a result of interactions with weather events, which I think we do agree are random.

[jimbob]

And my other point is that with events such as the ice age ending, and near extinctions that there are new environmnets that could be exploited, so one should see an increase in the evolutionary ratre afterwards, and this initial setup would be influenced by the random events.

Like a river's course shifting chaotically, or a drunkard's walk.

[mijopaalmc]

zosima and Belz...-

My point is that the orderly operation of an ionization smoke detector is not non-random. The only reason that it works that the americium-241 produces enough ionizing radiation to sustain a detectable and steady voltage. It simply wouldn't work predictably if you used uranium-238 instead.

[Belz...]

But radioactive decay is random, right Mijo ?

[zosima]

except that the survival must also be a result of interactions with weather events, which I think we do agree are random.

And my other point is that with events such as the ice age ending, and near extinctions that there are new environmnets that could be exploited, so one should see an increase in the evolutionary ratre afterwards, and this initial setup would be influenced by the random events.

Like a river's course shifting chaotically, or a drunkard's walk.


Thats a fair position to take and I'm perfectly willing to agree to disagree. That said I tend to think that even things like weather smooth out in to factors that act more or less deterministically when you're talking about evolutionary time scales. I also think that scenarios where the fate of a species depends on a single weather event or one summer's melt-water end up looking like very elaborate contraptions rather than solid hypotheses. So, to me, whether or not they ever happen; whether or not they're important, seems akin to asking whether or not quantum tunneling is an important factor to consider when determining the position of my cat. That said I think we've both made these exact same arguments in previous posts, so I'm ready to leave our dispute standing.

Mijo:
Last Post:

My point is that the orderly operation of an ionization smoke detector is not non-random.

2 Posts Ago:

Similarly, the process that make an ionization smoke detector work, radioactive decay, is random, the result, the actual functioning of the detector is not.


So the behavior of a smoke detector is not non-random, but a smoke detector's behavior is not random? Two posts. Complete contradiction. I'm glad you're up to form. I guess its time to redefine 'non' in the next post.


an ionization smoke detector...simply wouldn't work predictably if you used uranium-238 instead.(Of Americum-241)

Good point, let me just add that:
If trucks had Jello for wheels we wouldn't use them for shipping.
If birds had no wings they would be unable to fly.
If my hands were made of string-beans I wouldn't typing.
If light were pasta it would travel much slower.
......
Seriously I think this argument is sooooooooooooooooooo done. :p

[jimbob]

Thats a fair position to take and I'm perfectly willing to agree to disagree. That said I tend to think that even things like weather smooth out in to factors that act more or less deterministically when you're talking about evolutionary time scales. I also think that scenarios where the fate of a species depends on a single weather event or one summer's melt-water end up looking like very elaborate contraptions rather than solid hypotheses. So, to me, whether or not they ever happen; whether or not they're important, seems akin to asking whether or not quantum tunneling is an important factor to consider when determining the position of my cat. That said I think we've both made these exact same arguments in previous posts, so I'm ready to leave our dispute standing.


Fair enough..
I would actually take a different view as to timescales though.

Two generations:
Little difference between the two, we agree here I think.
ETA: Many potentially beneficial traits won't survive at this stage, but enough overall will provided the population survives...

many generations in stable environment (thousands of years+)
There will be adaptations to the stable parts of the environment, e.g whatever predators there are in a hot dry desert, any prey will still be adapt ed to the heat and aridity.

Many features will be predictible, i.e. randomness would be less important


Geological timescale:
Large unpredictible events are likely to occur within this timescale and set things partly to "year zero", when a different set of random patterns are likely to emerge. There would have been no way to predict what would have arisen 2million yars after the end of the Jurassic, ditto the Cretaceous, or the Cambrian. I would argue that this would not be simply due to a lack of information but to the essentially random nature of the initial evolutionary directions in the initial new environment.

In other words I am saying that the physical environment will have a "fitness" landscape which might be fairly stable, but the interactions between the organisms in the new environment is plastic, and is so until they begin to fill the niches. ETA: when randomness becomes less important again though the "directions" have been partly "set" randomly. (once there is a large carnivore, and a large herbivore, the herbivore is not going to evolve into a competing carnivore.

[zosima]

Fair enough..
I would actually take a different view as to timescales though.

Two generations:
Little difference between the two, we agree here I think.
ETA: Many potentially beneficial traits won't survive at this stage, but enough overall will provided the population survives...

many generations in stable environment (thousands of years+)
There will be adaptations to the stable parts of the environment, e.g whatever predators there are in a hot dry desert, any prey will still be adapt ed to the heat and aridity.

Many features will be predictible, i.e. randomness would be less important


Geological timescale:
Large unpredictible events are likely to occur within this timescale and set things partly to "year zero", when a different set of random patterns are likely to emerge. There would have been no way to predict what would have arisen 2million yars after the end of the Jurassic, ditto the Cretaceous, or the Cambrian. I would argue that this would not be simply due to a lack of information but to the essentially random nature of the initial evolutionary directions in the initial new environment.

In other words I am saying that the physical environment will have a "fitness" landscape which might be fairly stable, but the interactions between the organisms in the new environment is plastic, and is so until they begin to fill the niches. ETA: when randomness becomes less important again though the "directions" have been partly "set" randomly. (once there is a large carnivore, and a large herbivore, the herbivore is not going to evolve into a competing carnivore.

That definitely clarifies the point you're making. I'd appreciate it if you would elaborate. Why would we expect a random path to be taken after a major ecological event? While the change would be quick, dramatic, and quite probably unpredictable, why does a random element also come in? Can you give an example of a random scenario after a large event?

[articulett]

He thinks the unpredictable event IS "random" and this makes selection random... because he's looking at from before the event occurs. I know it's garbled, but to him it makes sense.

A scientist would say, a creature evolves to fit it's environment... and including the assorted events in that environment... if they do not, they perish. If you belong to a species that can't do well when an asteroid hits the part of the planet, you die out... other life that was better adapted survives and evolves in your place.

We see all of the environment including tornadoes and such as "part of the environment" that "selects"-- part of the culling process winnowing what evolves. Jim and Mijo teleport themselves back in time before any "hypothetical" events so they can call selection "random" just like they call mutation and then conclude that "evolution is random" by virtue of being probabilistic (whatever the hell that means).

They speak of mutation in regards to evolution as a concept... but in order to focus on unpredictability and "randomness" they turn to specifics when it comes to selection--suddenly we are out of the realm of abstraction and into the realm of specific hypotheticals just so they can feel like it's meaningful to call evolution random. It's a true mind numbing game, zosima-- just like mijo's very elastic definition of random. You will feel like you are being drawn into crazy land, and there is no exit.

And they will do this as long as they both have an audience... and a couple of more of same folks will regularly chime in with meandering off topic pedantry to confuse the issue. It's not you. And it's not fixable.

[jimbob]

Whilst articulett thinks that aircraft evolved*...

I don't like consistently attacking what I think is someone's view (and unlike articulett, I actually don't have anyone on ignore) rather than their arguments, so I'll leave my comments at that for now.

ETA:
I'll explain the rest of my point later, but interactions between organisms whilst being hard to model in their completeness, do show chaotic behaviour (http://en.wikipedia.org/wiki/Lemming#cite_ref-0), indeed we made a simple model of one type in our physics lectures when I was at university.

In the new environment, the "interactions" landscape is fairly flat, so, just as a river's drainiage system and its initial course is chotic, and thus significantly affected by quantum events, so the interactions between the emerging (and initially less-well adapted) organisms is going to be too.

At the beginning of unicellular life there was no inevitibility about the evolutionof any ecology like ours, it wasn't merely unpredictible but that it was not yet determined, as it would be significantly affected by quantum events. I am unsure whetther articulett would even accept the question as to whether ecosystems like ours were inevitable at this stage, or even later.



*maybe OK in a general diacussion, but this "development" is not similar to biological evolution, although William Dembski (prominanet ID proponent) likes to equate them (http://www.uncommondescent.com/evolution/intelligent-evolution-if-the-courts-rule-against-id/).

The evolution here would be reconceived not as blind evolution but as technological evolution. Nor would it be committed to Darwin’s idea of descent with modification. But, hey, it would still be evolution

[cyborg]

What the **** is your obsession with quantum events all about? Seriously.

[mijopaalmc]

What the **** is your obsession with quantum events all about? Seriously.

Uh....they provide the basis for the variation that is necessary for evolution to occur, and, even though they are, to the best of humanity's collective knowledge, random, they converge to describe the deterministic behavior of Newtonian mechanics.

[cyborg]

Uh....they provide the basis for the variation that is necessary for evolution to occur,

Uh no.

and, even though they are, to the best of humanity's collective knowledge, random, they converge to describe the deterministic behavior of Newtonian mechanics.

Dare I state the simple fact that variation is not dependant in any way whatsoever on "randomness"?

[mijopaalmc]

Uh no.

Uh....mutation, which provides the variation for the process of evolution observed here on the planet Earth, is a quantum mechanical phenomenon and therefore, to the best of our knowledge, random.

Dare I state the simple fact that variation is not dependant in any way whatsoever on "randomness"?

You could certainly say that, but you would be dead wrong because of the reason given above.

[cyborg]

Uh....mutation, which provides the variation for the process of evolution observed here on the planet Earth,

Goal-post shift.

Answer the question:

It is a necessary property of variation that the variation is random in all cases?

[mijopaalmc]

Goal-post shift.

Answer the question:

It is a necessary property of variation that the variation is random in all cases?

I see the problem here is that you want to redefine the parameters of the discussion in mid-stream. We have always discussed evolution as the process that we have observed here on Earth, not some "abstraction" that covers all possible cases of evolution. That is why the discussion has been predominately about genes, phenotypes, and natural selection. In essence, it is you who is shifting the goal posts to talk about variation in general and selection in general.

And no, neither variation in general nor selection in general for evolution in general to occur, but mutation and natural selection can both be random, and evolution by natural selection will still occur.

[cyborg]

I see the problem here is that you want to redefine the parameters of the discussion in mid-stream.

No. The problem is that if you define something as being necessary for evolution then it implies that if it does not have that property then the conditions for evolution are broken.

Abstract or not this applies: if it is merely variation only that is necessary for evolution then the type of variation is not contigent.

Theories also tend to have to cope with the abstract because of this little thing called "the prediction" - e.g. what is the prediction of the theory when the nature of variation is changed?

Continually stating things such as "QM is random, QM is small, therefore QM rules them all!" isn't interesting or useful in the least.

[mijopaalmc]

cyborg-

Does natural selection divide populations into two mutually exclusive groups of phenotypes: one where all of the individuals who possess its constituent phenotypes always survive and the other where none of the individuals who possess its constituent phenotypes ever survive?

If it does, then evolution by natural selection is deterministic.

If it doesn't, then evolution by natural selection is random.

[Dancing David]

Uh....they provide the basis for the variation that is necessary for evolution to occur, and, even though they are, to the best of humanity's collective knowledge, random, they converge to describe the deterministic behavior of Newtonian mechanics.


Really?

No they don't.

You can have natral selection through other means, random mutation is not the only way.

There is variation the expression of traits, say the length of a bone. For various reasons the length of the bone will vary, it could be from the genes that appear in five other expressed areas of the genome. So say that each individual has this trait but that the length of the bone will vary by 5% around the mean. So the bone will tend to have x length but will vary by some amount determined by the alleles at the five sites. (Length=x of prior parent varied by +/- 5%)

An indiviual can have a shorter bone or a longer bone or a bone on the mean. Now say that for reasons of contingent history a population of the species becomes isolated from the rest of the population and that for some reason they all have the longer set of the five alleles. So what will happen over time, due to the breeding they will tend to have a similar bone length but thier mean bone length will be higher than the original bone length. They will also have a five percent variation around the mean but thier mean bone length is longer than the original pool.

Now say that there is some selective benefit to having a longer bone, and the isolated population begins to have greater reproduction in the memebers of the population. For a while the population will have greater than 5% variation around the mean , yet over time the population is likely to stablize at a new mean with 5% variation around that mean. But the mean of this isolated population will be significantly higher than the original population.

This does not require random mutation.


Nor does random mutation depend upon quantum mechanics, nor does QM converge to describe Newtonian mechanics.

[Dancing David]

Uh....mutation, which provides the variation for the process of evolution observed here on the planet Earth, is a quantum mechanical phenomenon and therefore, to the best of our knowledge, random.


Really?

Mutation is the only way the that natural selection can occur?

Why then do artic animals have white fur? Are you sure that in all cases it is due to mutation?

What if it is from the expression of double recessive traits?

How did mutation become QM?

Copying and other errors can occur at the classical level without QM.

[cyborg]

If it does, then evolution by natural selection is deterministic.

If it doesn't, then evolution by natural selection is random.

Counterpoint - are all the reasons why one instance of a phenotype may be in one group and not the other necessarialy arbitrary?

If not then your version of natural selection is too simplistic.

[Belz...]

Uh....mutation, which provides the variation for the process of evolution observed here on the planet Earth, is a quantum mechanical phenomenon

Er... no.

[zosima]

ETA:
I'll explain the rest of my point later, but interactions between organisms whilst being hard to model in their completeness, do show chaotic behaviour (http://en.wikipedia.org/wiki/Lemming#cite_ref-0), indeed we made a simple model of one type in our physics lectures when I was at university.

In the new environment, the "interactions" landscape is fairly flat, so, just as a river's drainiage system and its initial course is chotic, and thus significantly affected by quantum events, so the interactions between the emerging (and initially less-well adapted) organisms is going to be too.


Actually the article you linked to says that we don't understand lemming population fluctuation. But it seems to suggest scientists are making progress in understanding it. I'm not sure what is chaotic about that.

Beyond that I think I'm pretty much done with this discussion. Your answer to my question is that "some systems are chaotic and thus necessarily are influenced by quantum mechanical randomness". This is just a huge fallacy. First, there is a huge difference between a chaotic system and a random one. Second, being a chaotic system doesn't mean it is affected by quantum mechanics. Chaotic systems are sensitive to initial conditions, but sensitive doesn't necessarily imply quantum sensitive. Third, quantum effects are really only important in sciences with the word quantum in the name, like quantum physics and quantum chemistry. Other systems work on a high enough level that quantum effects smooth out, so that while the systems are complex, they are not random. In fact they are incredibly reliable.

I think there have been several posts including some of my own that show why quantum physics is not an appreciable effect in evolution or in most natural sciences, I'm not going to repeat my reasoning here.

So now that I'm clear that this whole "evolution is random" argument boils down to "there exists a science called quantum physics" I'm pretty sure there's no reason to continue, jimbo.


@Cyborg,Belz,David Please, don't let Mijo resurrect himself by allowing him to completely ignore the argument he just lost and start a new one with you guys. If you want to continue arguing with him I would recommend you mock him with some of the silly things he's said in previous posts.

For example:
"The orderly operation of a smoke detector is not non-random" and "The actual functioning of a smoke detector is not random"
"Any event that has strictly more than one possible outcome is random"
"An outcome from a finite set of outcomes with 0 probability is random"
"Ballistics is not random, but a dart board is random"
"Everything is random"
"I've determined that people publish papers on statistics, thus evolution is random"
"If you used something other Americum-241 in a smoke detector it wouldn't work, thus evolution is random"
"Scientists use random variables to do statistics, thus whatever they're studying must be a random process. Look they both have random in the name, thus evolution is random."
Lets not forget that he doesn't know the difference between a finite set, an infinite set and, an uncountably infinite set.

Well thats a start, I catch one of these approximately every 2 Mijo posts. I think my favorites are the non-sequitur examples. I think I like those even better than the complete contradictions.

[jimbob]

This is just a huge fallacy. First, there is a huge difference between a chaotic system and a random one. Second, being a chaotic system doesn't mean it is affected by quantum mechanics. Chaotic systems are sensitive to initial conditions, but sensitive doesn't necessarily imply quantum sensitive.

I was under the impression it is still the current understanding that chaotic systems are sensitive at this level. It was when I was at university. IIRC, Sol Invictus, whose physics is probably more current than mine agreed...

ETA:


Here:

Yes, that is still the understanding, and that alone makes your definition (and mijo's) not very useful.

But actually (as I keep trying to explain) quantum randomness is pretty much a red herring in this discussion. Even if it didn't exist and the system was classically deterministic at the level of microscopic interactions, the presence of chaos makes it totally unpredictable. You can never measure the initial conditions with perfect accuracy even in a world without QM, and if the system is chaotic the uncertainty will grow exponentially (that's the definition of chaos), meaning - as in my example of the red gas molecule - you have no information at all after a relatively short time.


I would argue that it does make a philosophical difference.

The difference between being unpredictible but pre-determined, and random, i.e. not predetermined.

I would argue that, due to the nonlinear amplification of quantum uncertainties, chaotic systems are random over long enough timescales.

The smoke detector behaviour is not chaotic, so events can be averaged out with large numbers.

[Belz...]

@Cyborg,Belz,David Please, don't let Mijo resurrect himself by allowing him to completely ignore the argument he just lost and start a new one with you guys. If you want to continue arguing with him I would recommend you mock him with some of the silly things he's said in previous posts.

I'll do more than let him get away with it. I'll ignore his contributions from now on. He has no understanding of the subject at hand and shows no willingness to improve said understanding. What's the point of wasting energy on someone like that ?

[Wowbagger]

To play Devil's Advocate, a little bit: The smoke detector thing might not be a contradiction.

I could call Evolution "random" in one post, then "non-random" in another, but they would not contradict, if I used different meanings of the word in each post.

Granted, this is dishonest and/or confusing: One should try to remain consistent with their usage of terminology. But, it would still be valid, in a minimal manner.

Perhaps if Mijo started clarifying his statements better, we can sort this kind of stuff out.

[mijopaalmc]

To play Devil's Advocate, a little bit: The smoke detector thing might not be a contradiction.

I could call Evolution "random" in one post, then "non-random" in another, but they would not contradict, if I used different meanings of the word in each post.

Granted, this is dishonest and/or confusing: One should try to remain consistent with their usage of terminology. But, it would still be valid, in a minimal manner.

Perhaps if Mijo started clarifying his statements better, we can sort this kind of stuff out.

You know, I have said this before and I will say it again:

Since randomness and non-randomness both lead to orderly behaviors, orderliness is neither inherently random nor inherently nonrandom. Observation of orderly behavior in a physical system supports neither the hypothesis that the system is random nor the hypothesis that the system is non-random. Thus, it is not dishonest to say that the functioning of an ionization smoke is neither random nor non-random, because it is the orderly result of many random processes.

[zosima]

You know, I have said this before and I will say it again:

Since randomness and non-randomness both lead to orderly behaviors, orderliness is neither inherently random nor inherently nonrandom. Observation of orderly behavior in a physical system supports neither the hypothesis that the system is random nor the hypothesis that the system is non-random. Thus, it is not dishonest to say that the functioning of an ionization smoke is neither random nor non-random, because it is the orderly result of many random processes.

Non-random means not-random. Something cannot be random and not random at the same time. Thus your statement defines a contradiction.

You might try to argue something is both not-random and not-deterministic. This would be a fair position to take wrt evolution. But, of course, this would imply you concede that evolution is not random.

@Jimbo, how does posting a quote of Sol disagreeing with you support your contention? He says:
1. Quantum mechanics is a red herring(ie distracting irrelevant)
2. Chaotic systems are completely unpredictable without quantum mechanics. (ie quantum mechanics is not generally relevant to the discussion of chaotic systems)

Some things he doesn't say:
1. Quantum mechanics matters to anything in evolution.
2. Quantum mechanics is important to the description macroscopic systems.
3. Macroscopic chaotic systems are sensitive to quantum mechanical effects.

There is a philosophical difference about whether quantum mechanics is fundamentally random but it is irrelevant to evolution. You've made it apparent that quantum mechanics is the lynchpin of your "evolution is random" position. So this is over. Even your sources agree.

[Dancing David]

Mijo,

Is mutation the only way that a genome can express traits that are subject to natural selection?

[articulett]

What the **** is your obsession with quantum events all about? Seriously.


Ooh... I know the answer... pick me, pick me...

since quantum events are random, by semantic extrapolation anything that involves any quantum even (including all matter) is "random"... since (per their loose definition of random) all things that have random components ARE themelves random...

They don't want to be clear--they want to believe that scientists are saying evolutions is random. No scientist is saying this, of course... but they will only interpret the words that leads them to conclude that they are.

Come on, I want kudos-- I called this game over a year ago. They are creationists--or at least apologists--and they NEED to believe that scientists think evolution is "random" (whatever the hell that means) just like Kleinman needed to believe that the mathematics don't support evolution. All "cdesign propentists" have the little thing they need to be true to support their belief. Mijo and Jimbob need evolution to be "random". All their conversations must lead back to evolution being random--or, at least, "not non-random". Obfuscation beats clarity for a creationist. Understanding and conveying natural selection makes the invisible creator a less credible alternate "hypothesis". They don't want to be "clear"--they want evolution to be "random".

[jimbob]

@Jimbo, how does posting a quote of Sol disagreeing with you support your contention? He says:
1. Quantum mechanics is a red herring(ie distracting irrelevant)
2. Chaotic systems are completely unpredictable without quantum mechanics. (ie quantum mechanics is not generally relevant to the discussion of chaotic systems)

Some things he doesn't say:
1. Quantum mechanics matters to anything in evolution.
2. Quantum mechanics is important to the description macroscopic systems.
3. Macroscopic chaotic systems are sensitive to quantum mechanical effects.

There is a philosophical difference about whether quantum mechanics is fundamentally random but it is irrelevant to evolution. You've made it apparent that quantum mechanics is the lynchpin of your "evolution is random" position. So this is over. Even your sources agree.

We do agree in the following part of the discussion:


I am slightly puzzled by your statement:

My bad - I missed your "significantly", which was rather crucial! In that case, while I still prefer my definition (predictable versus unpredictable, at least in the context of broad phenomena), I more or less agree

Context within spoiler

I am slightly puzzled by your statement:

Yes, that is still the understanding, and that alone makes your definition (and mijo's) not very useful.
If this defintion made everything "random", then I would agree with you, but it doesn't: the Earth's orbit, for example isn't significantly affected even by cometry impacts . (I would be interested to know if there is any assessment on the potential effect of the Mars-sized body that helped create the moon...)

This ultimately random aspect of chaotic systems would mean that a probabilistic treatment for natural selection isn't just a good model, but does fundamentally reflect what happens... Belz, for example had been arguing agianst that (IIRC). And Articulett refuses to acknowledge that natural selection can be anything other than "nonrandom". I suggested, "probabilistic but not haphazard", and was accused of being wishy-washy and unclear.

As has been said before, creationists like to pretend that evolution is haphazard, and that this is what scientists mean by random.

Chaotic systems are ultimately not only unpredictible, but random over long enough timescales.

Only nonlinear systems are significantly affected by quantum uncertainty. Linear systems are not. The smoke detector is a linear system.

If the behaviour of evolution was unpredictible but non-random, then it was inevitable at the emergence of life that our ecosystem would have developed as it is now (with only insignificant differences).

I doubt this, for the reasons I have given previously.

[Belz...]

Ooh... I know the answer... pick me, pick me...

since quantum events are random, by semantic extrapolation anything that involves any quantum even (including all matter) is "random"... since (per their loose definition of random) all things that have random components ARE themelves random...

Which fits quite nicely with Mijo's definition of "random", though he himself denies that.

[jimbob]

Belz, I am arguing that:

Systems at the quantum scale are random, (I think we agree on this)

Linear systems (e.g. smoke alarms) are non random, as quantum fluctuations are insignificant: (I think we agree on this too)

Nonlinear systems can be truly random because if they are significantly affected by ranom quantum events. (Even though Sol prefers a different wording, he agrees that this is the case for chaotic systems).

Note how this differs from what articulett claims I am saying.

This also answers cyborg's question as to why I am "obsessed" with quantum events.

To the best of our understanding about the universe, quantum events are random.


I would turn the question round:

Doesn't the statement that "evolution is non-random" imply that its course is inevitable, even if not predictable? In other words as soon as life emergerd it was inevitable that about 3.8 billion years later the ecosystem would look as it does now with only insignificant differences? Doesn't that also mean that in 100 or 1000 years from now the ecosystem is already determined with only insignificant differences?

I would have thought that when hominids discovered fire, spears, and many tools was random. The paleolithic lasted a long time. These inventions had a significant effect on the evolutionary course of many other organisms, not just hominids.

[cyborg]

This also answers cyborg's question as to why I am "obsessed" with quantum events.

No it doesn't - your obsession is clearly around demonstrating that, "homo sapiens may not necessarialy have evolved!", the explanation for which for some reason requires quantum mechanics(!?).

Doesn't the statement that "evolution is non-random" imply that its course is inevitable, even if not predictable?

Class. Instance. ****.

Maybe you'd like to answer the question about variation?

[jimbob]

what question?

If something is significantly affected by random events then it can be said to be significantly affected by random events and not nonrandom

[cyborg]

If something is significantly affected by random events then it can be said to be significantly affected by random events and not nonrandom

That sentence was too significnantly affected by random events to be meaningful. Sorry.

[jimbob]

OK: If something is significantly affected (i.e. its outcome is significantly altered) by random events then it can't be nonrandom.

[articulett]

The smoke detector, Jimbob...

[jimbob]

It isn't a nonlinear system, so


Linear systems (e.g. smoke alarms) are non random, as quantum fluctuations are insignificant: (I think we agree on this too)

[articulett]

I think quantum fluctuations are irrelevant to understanding evolution as well. They are only relevant if you have some weird need to describe evolution as random or to insist that it's "not nonrandom". I think you may be building a case for your argument in your head, but it really doesn't translate to anything meaningful or useful n writing.

[mijopaalmc]

Linear systems (e.g. smoke alarms) are non random, as quantum fluctuations are insignificant: (I think we agree on this too)

The reason that the smoke detector works is that the decay of many atoms of americium-241 at random creates a steady current with a predictable value. The moment-to-moment variations in the current (which do occur because the americium-241 does not necessarily produce the same amount of alpha-particles in every time interval) do not significantly effect to mean current and there is therefore a distinguishable difference "no smoke" and "smoke" states of the smoke detector. Replacing the americium-241 with an isotope with a much lower specific activity (e.g., uranium-238) makes it impossible to distinguish between the two state because the moment-to-moment variation in the current now swamps out the mean current.

[Belz...]

Belz, I am arguing that:

Systems at the quantum scale are random, (I think we agree on this)

Linear systems (e.g. smoke alarms) are non random, as quantum fluctuations are insignificant: (I think we agree on this too)

Fair enough.

Nonlinear systems can be truly random because if they are significantly affected by ranom quantum events.

Examples of known non-linear systems, please.

Doesn't the statement that "evolution is non-random" imply that its course is inevitable, even if not predictable? In other words as soon as life emergerd it was inevitable that about 3.8 billion years later the ecosystem would look as it does now with only insignificant differences? Doesn't that also mean that in 100 or 1000 years from now the ecosystem is already determined with only insignificant differences?

Yes. But then it depends what you mean by random. By the definition you gave above, what you describe here is entirely deterministic and the answer to your question is yes. If you want it to be partially random you're going to have to change your definition.

[Wowbagger]

Evolution could not be called "random", due to quantum fluctuations, any more than any other science, because all of those other sciences are also effected by quantum fluctuations. And, it would not even have terribly significant effects at that.

I think the only science where quantum fluctuations play a significant role is in... quantum mechanics. Any higher level and the effects (though still there) become more and more averaged out.


ETA: I just realized I already made most of this point in the OP. It's been such a long time, I nearly forgot.

[Dancing David]

Which means that a smoke detector is non-random and natural selection isn't.

Mijo: are there ways the genome can vary and be acted upon by natural selection, other than mutation?

[mijopaalmc]

Which means that a smoke detector is non-random and natural selection isn't.

Mijo: are there ways the genome can vary and be acted upon by natural selection, other than mutation?

Genomes are not acted upon by natural selection; phenotypes are. Changes in the genetic sequences (and their expression, which lead to phenotype) are governed by quantum mechanics and are therefore random. However, not all events are equally likely to occurs, so over long periods of time the organism develops in an orderly fashion.

[jimbob]

Belz:

Nonlinear systems WP (http://en.wikipedia.org/wiki/Non-linear) include chaotic systems, which includes turbulent flow amongst others which affect the weather, itself a classic example of a chaotic system.

Many (ETA: maybe most) systems with lots of positive feedback loops are likely to be nonlinear; they would at least be bistable or multistable, and probably oscillatory. Negative feedbacks loops could increase temoporary islands of stability. All these are present in biological and ecological systems, for example the reduced adult cod population has probably resulted in increased predation of cod fry by the prey of adult cod, keeping the Grand Banks cod population low, despite fishing controls. This is an examople of a positive feedback loop.


Here (http://www.fortunecity.com/emachines/e11/86/rhythm.html) is a transcription of a 1989 New Scientist article about chaotic systems in biology, including population dynamics by Robert May, former president of the Royal Society (http://en.wikipedia.org/wiki/Robert_May,_Baron_May_of_Oxford) ( I am slightly dubious about the site host of the transcript, but the article seems fine):

The first few paragraphs talk about chaotic population dynamics.

Until recently, conventional analyses of population genetics showed that such selective effects could maintain variability within a species, but these static analyses tended to assume that the proportions of the different genotypes remained constant overtime. William Hamilton at Oxford, Simon Levin and David Pimentel at Cornell, Roy Anderson at Imperial College, London, and I have more recently studied the dynamic properties of the interactions among hosts and pathogens. The studies show that the proportions of any one genotype are likely to fluctuate chaotically from generation to generation. Such chaotically fluctuating polymorphisms are likely to be the rule rather than the exception.

One thing is certain. Biological systems, from communities and populations to physiological processes, are governed by nonlinear mechanisms. This means that we must expect to see chaos as often as we see cycles or steadiness. The message that I urged more than 10 years ago is even more true today: "not only in [biological] research, but also in the everyday world of politics and economics, we would all be better off if more people realised that simple nonlinear systems do not necessarily possess simple dynamical properties."

In the example from your post:


Doesn't the statement that "evolution is non-random" imply that its course is inevitable, even if not predictable? In other words as soon as life emergerd it was inevitable that about 3.8 billion years later the ecosystem would look as it does now with only insignificant differences? Doesn't that also mean that in 100 or 1000 years from now the ecosystem is already determined with only insignificant differences?
Yes. But then it depends what you mean by random. By the definition you gave above, what you describe here is entirely deterministic and the answer to your question is yes. If you want it to be partially random you're going to have to change your definition.

I would disagree. Near-identical nonlinear systems tend to diverge over time.

Slight differences get magnified, all the way up from the alpha particle to a weather system.

3.8 billion years ago, as life first emerged, there was no inevitibility about the shape of the ecosystem now. Even just after the KT event, the shape of the current ecosystem would not have been determined. A few hundred thousand years ago, most of the ecosystem might, except for those species later rendered extinct due to chance technological developments of mankind, some of which were more probable than others. (Agriculture seems to have been developed independently in the Fertile Crescent, South America, and China for example)

Wowbagger:
The maths says that these systems are significantly affected by truly random events*, i.e. it isn't just because of a lack of measurement accuracy that prevents me from knowing what quarter the wind will blow from over my house in 100 days time but that it will be significantly* influenced in effect by random events that haven't happened yet. Similarly for other weather conditions. There are also predictible factors that affect the weather, and it probably will be warmer.

Linear systems are not significantly affected, but chaotic systems are.

This doesn't mean that analyses are impossible, just that there has to be a probabilistic slant.

An anlogy: When running simulations of planetary formation, sometimes the orbital mechanics are chaotic. To see what would tend to happen, one can run many simulations with very similar starting conditions and see how many times certain outcomes occur. "With a Jupiter sized body in the position of Jupiter's orbit, an Earth-like planet formed in the correct orbit in x% of the simulations" A bit of googling could probably dig out real examples.

You can run the experiment many times and see how often particular outcomes occur; this can sometimes be a "virtual" experiment, if you know the interactions.

Here (http://news.bbc.co.uk/1/hi/sci/tech/7351428.stm) is a recent BBC news story which includes a probabilistic treatment of evolutionary outocmes by Professor Andrew Watson (http://www1.uea.ac.uk/cm/home/schools/sci/env/people/perspages/Professor+Andrew+Watson+FRS)

"We now believe that we evolved late in the Earth's habitable period, and this suggests that our evolution is rather unlikely. In fact, the timing of events is consistent with it being very rare indeed," he says.

"This has implications for our understanding of the likelihood of complex life and intelligence arising on any given planet."

Previous models are founded on the rationale that intelligent life on Earth emerged from a sequence of unlikely "critical steps".

Prof Watson identifies four - the emergence of single-celled bacteria; complex cells; specialised cells allowing complex life forms; intelligent life with an established language.

He estimates that the probability of each of these "critical steps" occurring in relation to the lifespan of Earth is no more than 10%.

Thus, the chances of intelligent life on any given Earth-like planet is tiny - less than 0.01% over four billion years.

Of course you could argue that this could be simply the lack of knowledge, but given the nonlinear systems involved, I would argue that it is essentially chance.

(The factor that he doesn't mention is the unknown potential number of habitible planets, "less than 0.01%" over the galaxy for Earth-like planets could still be a lot).


*whether or not an alpha particle ionises a few molecule of air does eventually lead to totally different weather patterns (at least according to the maths).

**i.e whether there is any wind at all, what speed it is, which direction (any of 360°)...

[jimbob]

My definition of random is that identical starting conditions within the whole system can lead to (significantly) different outcomes.

[cyborg]

"Significantly" different outcomes?

Your definition of random is... random. I wish you guys would just get on board with the notion that algorithmic complexity provides a much better understanding of the nature of randomness then the convoluted twists your are making in reason.

[jimbob]

Cyborg, was the rise of grasses inevitible at the time of the precambriann explosion?

Would the presence or absense of grasses make a significant difference to evolution of pretty much every land organism?

Of course it wasn't predictable, but nonrandom systems can still be unpredictable.

[cyborg]

Cyborg, was the rise of grasses inevitible at the time of the precambriann explosion?

If it was because the universe is fundamentally deterministic what differences would that make to anything? You are still left with the same tools to reason with. The evolutionary explanation stands regardless.

You refuse to get this.

[jimbob]

So a chaotic orbit isn't significantly affected by quantum events?

[cyborg]

I do not *********** care if it is or it is not. It changes nothing. You refuse to get this.

[jimbob]

I agree that the evolutionary explaination stands regardless, but there are many different outcomes that are possible, and haven't been predetermined as they rely on future random events.

[cyborg]

So.

It changes nothing.

DO YOU AGREE?

[Wowbagger]

Wowbagger:
The maths says that these systems are significantly affected by truly random events*, i.e. it isn't just because of a lack of measurement accuracy that prevents me from knowing what quarter the wind will blow from over my house in 100 days time but that it will be significantly* influenced in effect by random events that haven't happened yet. Similarly for other weather conditions. There are also predictible factors that affect the weather, and it probably will be warmer.

Linear systems are not significantly affected, but chaotic systems are.

This doesn't mean that analyses are impossible, just that there has to be a probabilistic slant.That doesn't dimish the fact that chaotic changes are still averaged out, nor the fact that the Theory of Evolution helps us predict various aspects of the system, with accuracy increasing as our information about it does.

[Dancing David]

Genomes are not acted upon by natural selection; phenotypes are. Changes in the genetic sequences (and their expression, which lead to phenotype) are governed by quantum mechanics and are therefore random. However, not all events are equally likely to occurs, so over long periods of time the organism develops in an orderly fashion.


But are there not 'changes' or variation in the genome, such as traits being reccessive and dominant that are not related to the mutations? Are artic foxes really white because of mutations or because of selection of alelles?

So if the conduction of electricity is goverened by QM, it is random?

[mijopaalmc]

That doesn't dimish the fact that chaotic changes are still averaged out, nor the fact that the Theory of Evolution helps us predict various aspects of the system, with accuracy increasing as our information about it does.

I'm not quite sure why people seem to continually overlook the fact that the "averaging out over time" does not make the system non-random, because every the simplest idealized models of probability (i.e., the ones where the random variable are independently and identically distributed and no causality is assumed) display convergence to a mean value with ever-decreasing variance (otherwise known and the central limit theorem and the law of large numbers).

[jimbob]

This is where I disagree with mijo:

nonlinear systems tend to diverge over time i.e. these differences get magnified not averaged out.

At the emergence of life 3.8billion years ago, there was no inevitibility about the emergence of grasses (or equivalent small wind-polinated land plants that grow quickly and thus can suppotrt large herbivore biomas). The emergence of grasses was affected by many small and truly random events that hadn't been predetermined at that time.

Without something occupying this niche, ecosystems would look completelty different. Many evolutionary pressures would be completely different, so the whole course of evolution for most land organisms would be signifficantly different.

I would argue that this is a valid use of "random".

What was inevitible was that successfully reproduceing organisms would demonstrate good adaptation to whatever environment they were in. Evolution can explain why and how organisms are the way they are, but the nonlinear nature of biological systems means that predictions are best described in terems of probabilities. Sometimes these probabilities are very high, e.g. given the presence of grassland, herbivores will evolve to eat this grass, and they will be preyed upon.



One can still make assessments on a probabilstic basis.

This news (http://news.bbc.co.uk/1/hi/sci/tech/7351428.stm) story discusses the chances of intelligent life evolving on a particular earth-like planet, and uses similar reasoning to that which I have done in a similar thread, including the low probability of intellignet life arisisng, using similar basic information, which, for my simple reasoning was that large complex organisms have exidsted for many hundreds of millions of years, and even large mammals have existed for tens of millions of years, in environments where any organism occupying our niche could have thrived. That it took so long implies that it is probably an unlikely occurance.

There is another opoint, I am saying that because nonlinear systems tend to diverge, evolution is probably only random for the majority of ecosystems over geological timeframes. Over shorter timeframes, with stable enough environments, evolution is probably nonrandom.

The random nature is most significant when the ecosystems are plastic, so most organisms are not very well adapted, and new potential niches are opened up, some of which will be closed, and which do will be dependent on how evolution runs in this particular instance.

This (http://www.nytimes.com/2007/06/26/science/26lab.html?_r=1&scp=6&sq=e.coli&st=nyt&oref=slogin) New York Times article (again) could show another way where randomness affects evolution.

Fast-Reproducing Microbes Provide a Window on Natural Selection

<snip>

Dr. Bennett was particularly curious about how organisms adapt to different temperatures. He wondered if adapting to low temperatures meant organisms would fare worse at higher ones, a long-standing question. Working with Dr. Lenski, Dr. Bennett allowed 24 lines of E. coli to adapt to a relatively chilly 68 degrees for 2,000 generations. They then measured how quickly these cold-adapted microbes reproduced at a simmering 104 degrees.

Two-thirds of the lines did worse at high temperatures than their ancestors, experiencing the expected trade-off. “If you’re a betting person, that’s the way you’d better bet,” Dr. Bennett said. But the pattern was not universal. The bacteria that reproduced fastest in the cold did not do the worst job of breeding in the heat. A third of the cold-adapted lines did as well or better in the heat than the ancestor. Dr. Bennett and Dr. Lenski published their latest findings last month in The Proceedings of the National Academy of Sciences.

To me, this implies that if there were several competing strains of bacteria, and they were placed in a cool environment and adated to this, the surviving strains would all become cold-adapted. However if the environment then changed and became hotter, those which had a cold-adaptation that was also (by chance) a heat-adaptation (or maybe a simple head adaptation by genetic-drift) would outcompete the other cold-adapted strains, which possibly wouldn't get a chance to evolve heat adaptation before becoming extinct.

Which organisms have the head start in the new environment would be random in this case.

ETA: And there is no reason to suppose that lab situations are unique in this.

[Wowbagger]

I'm not quite sure why people seem to continually overlook the fact that the "averaging out over time" does not make the system non-random, because every the simplest idealized models of probability (i.e., the ones where the random variable are independently and identically distributed and no causality is assumed) display convergence to a mean value with ever-decreasing variance (otherwise known and the central limit theorem and the law of large numbers).It depends on how you define "non-random".

While Evolution could be random in the sense of quantum uncertainty, it would be invalid to criticize it as random, because of that, because all of the other sciences are effected by quantum uncertainty, as well.

For the same reason, Evolution can not be called a "theory of randomness". It tries to predict emergent patterns in life forms, as precisely as possible; not throw up its hands to to the mercy of pure chance.

[articulett]

round and round and round it goes
as long as you feed the "random" trolls...

[jimbob]

Who is trolling, and why does articulett think so?

She seems to be the main person who doesn't have anything to contribute in this discussion, except to make claims about other posters.

Wowbagger, do you see what I am getting at wth the random factor being more important over geological timescales?

I am not critising evolutionary thory for being random, but there is a fundamental difference in the type of prediction and confidence between random and nonrandom systems.

It is possible to be very confident in predicting the Earth's orbit, position and velocity 100-million years from now. It isn't possible to do the same for an evolutionary course over this timescale into the future. This isn't just because it is predetermined but hard to predict, but that this evolultionary course isn't yet determined and will be significantly affected by future random events.

In stable environments or where there are constant selective pressures, there will be adaptation to these pressures, some of which are more probable than others. Over geological timescales the environments are not constant, and when they change, and the ecosystems are plastic, these ecosystems are subject to random changes that then set the course of evolution until another unstable period when random factors again become important.

Long periods of stable evolution, punctuated with "points of inflection" where ecosystems are plastic and subject to significant random alteration, the outcome of which will determine the general shape of the ecosystem and thus evolution until the next disruptive event.

Whether the event itself is random isn't really the point. It wipes enough of the slate clean so that the biological interactions can "set" significant selection criteria, and this criteria will depend on nonlinear interactions and be significantly altered by random events.

[cyborg]

Whether the event itself is random isn't really the point.

Then why bang on about Quantum Mechanics if:

It changes nothing.

?

[sol invictus]

nonlinear systems tend to diverge over time i.e. these differences get magnified not averaged out.

jimbob, a quick comment. You're using "non-linear" as a synonym for "chaotic". That's not really correct. Non-linearity does not always imply chaos, and I can think of linear systems that exhibit chaos.

For an example of the first, take air resistance. An object moving though air experiences a drag force that is proportional to velocity squared (so it's non-linear), but the results are quite predictable (it slows and stops). No chaos.

For the second, take a single frictionless particle bouncing around in a container with complicated walls. Perfectly linear, but chaotic (change the initial position a little and you make a huge difference in the position a little later).

Evolution - as I think we all now agree - is unpredictable (and probably chaotic) in many of its details, but predictable in some details and in its macroscopic behavior. Calling something like that "random", full stop, is obviously a mischaracterization.

[jimbob]

Whether the event itself is random isn't really the point.

Then why bang on about Quantum Mechanics if:

It changes nothing.

My full quote was:

Whether the event itself is random isn't really the point. It wipes enough of the slate clean so that the biological interactions can "set" significant selection criteria, and this criteria will depend on nonlinear interactions and be significantly altered by random events.


The event might have been inevitible, but its consequences weren't.

Back to the KT impact.

Whether the impact itself* was random, was not my point.

The consequences of the KT impact were random. Yes it led to the "Rise of The Mammals (TM)" but it needn't have; other truly random events were important. The impact, and other events where the envitonment changed significantly wiped the slate clean, and sensitised the ecosystem to developing in directions which had been affected by random factors, i.e which organism began randomly adapting to a particular niche, and how this affected the fitness landscape for other organisms.

The rise of grasses was another event that significantly altered the fitness landscape, and I would argue that such an occurrance could also lead to a sensitivity to random factors.

Over geological timescales I think it makes mores sense to describe the course of evolution as random. In short timescales, and with stable environments, I would agree that it isn't. However if people are discussing the evolution of humanity, which is a popular subject, then this evolution has been significantly affected by random factors.


*There is evidence that cometry Near Earth Orbits are chaotic (http://spaceguard.esa.int/NScience/neo/neo-where/mech.htm), which would make the impacts themselves sensitive to random events.

[jimbob]

Sol, I'd agree with most of what you are saying with a few caveats:


{nitpick}If something like air resistance (or energy) is proportional to the square of the velocity, then I would say that this is still a linear system. {/nitpick} However there are examples, supporting your point, where nonlinear systems are nonchaotic, even the classic pendulum which we were all taught as simple harmonic motion, isn't really a linear system as it relies on the approximation:
sin(x) -> x , for small values of x...

However the types of feedback loops in biological systems, (and ecosystems, which is what defines the evolutionary landscape) will mean that aspects of evolution are sensitive to chaotic systems.

My maths isn't good enough to know if all the interactions can even be analytically described, but there would be discontinuities, and significant sensitivty to random factors.

Evolution - as I think we all now agree - is unpredictable (and probably chaotic) in many of its details, but predictable in some details and in its macroscopic behavior. Calling something like that "random", full stop, is obviously a mischaracterization.


I'd agree with that statmenet, however I am saying that calling it "nonrandom" is also wrong. Especially over geological timescales, when there are periods where the evolutionary landscape is "randomly" altered.

[sol invictus]

{nitpick}If something like air resistance (or energy) is proportional to the square of the velocity, then I would say that this is still a linear system. {/nitpick}

Well, you could say that, but you'd be wrong. The differential equation has a term in it that's the square of the velocity. When you solve for the position as a function of time, you're solving a non-linear equation. Multiplying the solution by a constant does not result in a new solution, you cannot superpose two solutions, and you cannot write the equation as a linear operator acting on an unknown function. It's non-linear.

However there are examples, supporting your point, where nonlinear systems are nonchaotic, even the classic pendulum which we were all taught as simple harmonic motion, isn't really a linear system as it relies on the approximation:
sin(x) -> x , for small values of x...

Yes, that's another example.

[articulett]

Ah... it's time for me to point out once again:

"Having random components does not a "random process" make".

Not that it matters for those who desperately wish to believe this to be so.

[jimbob]

Well, you could say that, but you'd be wrong. The differential equation has a term in it that's the square of the velocity. When you solve for the position as a function of time, you're solving a non-linear equation. Multiplying the solution by a constant does not result in a new solution, you cannot superpose two solutions, and you cannot write the equation as a linear operator acting on an unknown function. It's non-linear.
Yes I had a brainstorm about that part

ETA: but my reasoning about the rest is unaffected.

[jimbob]

Sol, back to my points about chaotic systems.

They are significantly affected by random events.

Doesn't this mean that an asteroid in a chaotic Near Earth Orbit is also going to be significantly affected by random events, possibly to such an extent that it might hit either the Earth or Moon (or neither), with vastly different effects on the course of evolution.

Do you see my point about random factors being important over geological timescales?

[sol invictus]

Sol, back to my points about chaotic systems.

They are significantly affected by random events.

Doesn't this mean that an asteroid in a chaotic Near Earth Orbit is also going to be significantly affected by random events, possibly to such an extent that it might hit either the Earth or Moon (or neither), with vastly different effects on the course of evolution.

Do you see my point about random factors being important over geological timescales?

Sure - at any moment a giant asteroid could come along and smash the earth into tiny pieces, killing all life but some anaerobic bacteria (and thus rather drastically changing the course of evolution). Or intelligence could evolve, develop thermonuclear weapons, and engage in a nuclear war. Or the sun could capture a wandering star and go nova. Or a meteor strike could make all the giant lizards go extinct, allowing some furry rodents to take over the world and eat lots of chicken.

But you could say the same things about your pendulum - you claimed it was deterministic and predictable, but what if someone comes along and yanks it off its peg on a cosmic-ray-to-the-brain inspired whim?

The whole discussion is ridiculous. Everybody here (just about) agrees on the phenomena in question - we're just arguing over a word. But this is a complex process, and you just can't capture it very well with one word - you have to say a few more. Tough.

[articulett]

Jimbob... you argument is the equivalent of arguing that a random number generator is itself random... or it produces numbers "randomly" because we can't predict the outcome in advance and some small random change to the code can change the whole outcome.

No matter how you slice it, that still doesn't make random number generators "random" nor does it mean they generate numbers "randomly"... you can say that if you don't mind being unclear, but why would you?

And why would you insist on using such an unclear explanation in regards to evolution? Go to the other thread where a creationist is wondering how scientists could think this all came about randomly and see if you can convey any actual information about how order comes about from the randomness while insisting that evolution IS random.

The process that brings order to randomness is not, itself, random.

The Brazil nuts don't rise to the top of the mixed nuts randomly... they rise through a gravitational process, whereby the little peanuts fall between the spaces and end up on the bottom. If you want to call this random-- be my guest... but it make you look like a boob. Why in the world would you need to convince someone this is an intelligent way of describing such a process? And that goes triple for evolution.

You go on and on spinning these semantics as long as you have an audience. It's maddening to new people, I'm sure.

[Walter Wayne]

Ah... it's time for me to point out once again:

"Having random components does not a "random process" make".

Not that it matters for those who desperately wish to believe this to be so.
And it has been pointed out to Articulett before that having non-random components does not a non-random process make.

And her comment about random number generators is nothing like what Jimbob is arguing, and I assume from her description she is talking about pseudo-random number generators.

Walt

[Wowbagger]

Wowbagger, do you see what I am getting at wth the random factor being more important over geological timescales? I see the point that small random effects could be magnified over time. Which is one reason why it becomes more difficult to predict the future the further into the future you try to look.

But, that has nothing much to do with what I am talking about: Which has more to do wtih the general process acting over time.

I know you were not criticizing evolution, jim. But, I suspect others on here, might be.

[articulett]

No one here (except T'ai) is actually criticizing evolution (except in a backhanded way)... they just refuse to convey it a way that is understandable to those who don't understand evolution... leading me to wonder why they are so keen to convey evolution in a certain way, when all the experts find such descriptions obfuscating and misleading.

It is the same as insisting that a random generator is, itself, random...
Why would you do that if you were trying to convey what a random generator is or how it uses code to generate random numbers... how a known process can bring meaning to randomness...

Why would anyone insist on calling a random number generator "random" simply because it produces random numbers, the numbers are unpredictable, and a "random" change in the code would produce different results. The nonrandomness of a random number generator has nothing to do with whether a single event could change (or could have changed) the outcome! Whether a given sequence was "inevitable" per Jim's tangential argument is irrelevant to whether the random number generator (or evolution) is random in itself.

Jim continues to argue this inevitability point as though it means something in how we describe the process of evolution. It's backwards. It obfuscates. It's an awkward attempt to have it make sense to yourself to call evolution "random"-- or to convince yourself that scientists think this all came about "randomly".

The thing that brings order to the randomness (in the case of evolution, it's "selection") is not, itself, random... nor is the process that involves it. Having random components does not a random process make.

He wants you to agree that he's making sense in his description of evolution... that he's clear about something or conveying information to someone in a useful way. He wants to believe that he is more clear than the actual experts multiply quoted in this thread. He wants others to believe he has as much expertise on this topic as he seems to imagine.

[cyborg]

Well I find it odd that jimbob doesn't, to the best of my recollection, have any particular issue with genetic algorithms despite the fact that they don't really have much choice on the whole other than to deal with pseudo-random numbers. (I.e. it is technically a completely detereministic system).

Things must be random because otherwise they are determined - and ****, we can't have that because humans must have happened in that case! Creationists would love that!

The fact that it changes nothing about the evolutionary explanation doesn't seem to get through at all. You simply can't bring yourself to agree with this can you jimbob?

[jimbob]

I am not sure what cyborg's point is.

I agree that evolution is the explaination, it is just that descibing the situation as nonrandom, and denying the significance of random events is also wrong.

Random effects are probably of little importance over timescales of millions of years, but over longer timescales, they are likely to become more important.

The random events alter the selective landscape, in other words (and grossly simplifying) they change the selection criteria randomly.

If the selection criteria are subject to random alteration over geological timescales, then saying evolution is nonrandom*, is misleading.

SIngle words are going to be wrong.

As Sol has said it can't be explained in a single short soundbite.

Articulett, would you agree, that over geological timescales, random events have played crucial roles in the evolutionary course of the ancestors of almost any organism alive now?

Sure - at any moment a giant asteroid could come along and smash the earth into tiny pieces, killing all life but some anaerobic bacteria (and thus rather drastically changing the course of evolution). Or intelligence could evolve, develop thermonuclear weapons, and engage in a nuclear war. Or the sun could capture a wandering star and go nova. Or a meteor strike could make all the giant lizards go extinct, allowing some furry rodents to take over the world and eat lots of chicken.

But you could say the same things about your pendulum - you claimed it was deterministic and predictable, but what if someone comes along and yanks it off its peg on a cosmic-ray-to-the-brain inspired whim?

The whole discussion is ridiculous. Everybody here (just about) agrees on the phenomena in question - we're just arguing over a word. But this is a complex process, and you just can't capture it very well with one word - you have to say a few more. Tough.

But the point is that these events have happened in evolutionary history, whilst not in any of the pendulum demonstrations I have seen.

*which to me implies that there is nothing important about randomness

[Earthborn]

While Evolution could be random in the sense of quantum uncertainty, it would be invalid to criticize it as randomI think everyone in this thread agrees with that. Calling evolution "random" is not criticism. It is describing how it works, for some definitions of random.

It tries to predict emergent patterns in life forms, as precisely as possibleThat depends on what aspects of evolution one is studying. Many paleontologists are not predicting emergent patterns, but rather describing what paths evolution took in the past.

they just refuse to convey it a way that is understandable to those who don't understand evolution...You keep saying that, but you haven't shown why calling evolution "non-random" makes it easier to understand to those who don't already understand it, and neither have you shown why calling evolution "random" hinders understanding.

It is the same as insisting that a random generator is, itself, random...
Why would you do that if you were trying to convey what a random generator is or how it uses code to generate random numbers...As Walter Wayne said, you are talking about pseudo-random number generators. There are also "true random number generators". A random number generator is not necessarily code, it can also be hardware. A roulette wheel is also a random number generator, and I think everyone agrees that roulette is random (which of course does not mean it is unreasonable to predict that the wheel will go round instead of move in random directions; just because there are elements that are non-random does not make the process non-random)

[jimbob]

they just refuse to convey it a way that is understandable to those who don't understand evolution...
You keep saying that, but you haven't shown why calling evolution "non-random" makes it easier to understand to those who don't already understand it, and neither have you shown why calling evolution "random" hinders understanding.

Especially if anyone askes you about whether the KT event was important in the evolution of humans?

"Evolution is nonrandom but random events can alter evolutions course"?

[cyborg]

I am not sure what cyborg's point is.

You're obsessed with large red fish.

[Earthborn]

Well I find it odd that jimbob doesn't, to the best of my recollection, have any particular issue with genetic algorithms despite the fact that they don't really have much choice on the whole other than to deal with pseudo-random numbers. (I.e. it is technically a completely detereministic system).Genetic algorithms would work just as well with true random number generators, it is just that would make little practical difference.

Genetic algorithms are usually used to evolve code towards specific predesigned criteria, and the code that that is declared unfit is not bred at all. It is usually the equivalent of artificial selection. People using genetic algorithms are breeding digital lifestock, killing or castrating any beast that does not fit the criteria.

With real natural selection, the criteria for fitness are never entirely clear and are constantly changing in subtle ways and not so subtle ways, and there may be many different evolutionary strategies that can be followed. And just because one individual organism is less effective at reproducing itself does not necessarily mean it is not reproducing at all.

[articulett]

Actually, I've shown exactly how multiple experts who teach evolution describe the topic... it's a fallacy to think I would say "evolution is non-random"... though that is a lot closer to conveying the natural selection--the key component of evolution-- than saying evolution is random.

Your strawman is noted and dismissed. Your big red Herring giggled at. No biologist will agree that it makes sense to call evolution random. Those who teach evolution go out of their way to show how natural selection brings order to the randomness-- and not "randomly" either. If you want to sound like Behe, be my guest. But if you want to sound like you actually know what you are talking about... I suggest you read those who do instead of imagining you already understand all there is to know on the topic.

It is fascinating how the self appointed experts are so very uninterested on current developments in the field they imagine themselves having expertise in... nor are they ever interested in what the actual experts say, because, apparently, they think they are smarter than them.

[cyborg]

Genetic algorithms would work just as well with true random number generators, it is just that would make little practical difference.

That is kinda my point - those obsessed with the "purity" of randomness are obsessed with red herrings.

Genetic algorithms are usually used to evolve code towards specific predesigned criteria, and the code that that is declared unfit is not bred at all.

More than familiar with how they work.

So I will pose the same question I posed to jimbob: what exactly stops me from not specifying a specific predesigned criteria and do you suppose that should cause any great impact on how one should describe the process?

[Earthborn]

That is kinda my point - those obsessed with the "purity" of randomness are obsessed with red herrings.I don't think anyone is obsessed with the purity of randomness, but saying that things that are chaotic and affected by true random factors as the 'butterflies' are "non-random" can be misleading.

So I will pose the same question I posed to jimbob: what exactly stops me from not specifying a specific predesigned criteria and do you suppose that should cause any great impact on how one should describe the process?"Should" ? I'm not interesting in moral judgements. I don't think there is a single proper way in how one ought to describe the process.

One could describe the process in many different ways, and many different ways would be entirely correct. They may represent different ways of looking at the process. You can look at evolution from the perspective of an individual organism and its chances of reproducing. From that perspective, an organism facing many random threats and opportunities, and sometimes exhibits random behaviour.

You can also look at evolution from the perspective of populations and how they adapt to their environment, something articulett apparently insists we do. From that perspective, natural selection appears non-random if we assume the environment is relatively stable.

Another perspective is that of looking at the entire history of evolution itself and how life copes with quite random climate changes and global catestrophes.

And then there is of course the whole gene-centered view of evolution that is so popular. One view is not wrong because the other is right. But looking at it from a different scale can make things appear random that appear orderly from another.

[articulett]

I'm not "apparently insisting" anything... I'm illustrating carefully and repeatedly how the experts convey understanding of evolution and why they--those who teach the subject-- write books and convey their understanding to millions... never refer to evolution as random... and why they find those who do so misleading.

How sad for you to have missed that point in your need to believe that I "insist" on a certain description. I don't insist on a certain description. IThose who do generally insist on the describing evolution as random-- and like T'ai and Behe all the people I know who do so, are creationists (though some deny being creationists.) All those who do so, also pretend that I'm insisting on describing it a certain way while ignoring the fact that I posted 3 peer- reviewed scientist respected in the field on this very subject.

Why the need to mischaracterize me as having motives more obvious in you? Anyone can go back and read the thread and actually see what I've said compared to what you've imagined me "apparently insisting", you know.

[mijopaalmc]

But looking at it from a different scale can make things appear random that appear orderly from another.

I think this is the great divide: those who argue that evolution is non-random see its orderly long term behavior and insist that such behavior is non-random. However, since such orderly long-term behavior exists even in the idealized models of probability that assume the random variables under are independently and identically distributed (conditions that I think everyone can are random), the observation of long-term orderliness does not make the process itself non-random.

[Belz...]

Sol, back to my points about chaotic systems.

They are significantly affected by random events.

Exactly how is one system "significantly" affected by random events and another isn't ?

Are we still dancing between one definition of "random" and another ?

[Belz...]

I'm not "apparently insisting" anything... I'm illustrating carefully and repeatedly how the experts convey understanding of evolution and why they--those who teach the subject-- write books and convey their understanding to millions... never refer to evolution as random... and why they find those who do so misleading.

Articulett, admitting such a thing would mean that they are not "better" than everybody else.

[Dancing David]

Sol, back to my points about chaotic systems.

They are significantly affected by random events.

Doesn't this mean that an asteroid in a chaotic Near Earth Orbit is also going to be significantly affected by random events, possibly to such an extent that it might hit either the Earth or Moon (or neither), with vastly different effects on the course of evolution.

Do you see my point about random factors being important over geological timescales?

Not really, sensitive dependence on initial conditions is not dependant on randomness, it is dependant upon the ability to set back to initial conditions. Like the maps of pendulum direction in rotation, they are chaotic, but if one were able to return the pendulum to the same spot (the matter of precision0 then it would end up rotating the same direction.

Same too with your orbital example, it is a deterrministic system, with an unpredictable outcome.

But I myself do view chaotic systems as frequently pseudo random.

To get the issue back on track regards evolution, the genome is blind to the future enviroment, that is why traits that were not impacting reproduction can impact reproduction later, the organism is in a new enviroment.

It doesn't matter that the asteroid is pseudo random in it's impact at all, evolution is what it is. The placement of organisms can be psuedo random regards distribution of traits in an enviroment but the process that leads to reproductive success is deterministic.


So again , you have your chocolate in my peanut butter or you have your peanut butter in my chocolate.

Balloning insects are sort of ranomly dispersed depending on the heigth they reach, however ones they are in the enviroment, eating is determinsitic, the reproduction is deterministic. I am a randomist myself but thanks to Taffer and Articulette I now understand what they mean when they say that natural selection is determined. It is determined, the course of it is effected by random and pseudo random events.

[sphenisc]

So I will pose the same question I posed to jimbob: what exactly stops me from not specifying a specific predesigned criteria and do you suppose that should cause any great impact on how one should describe the process?


The fact that "a" is singular and "criteria" is plural. :)

Or is that a double negative, in which case nothing does - I think.

[Wowbagger]

I had pasta in a tomato and pesto sauce for dinner, last night.

I'm sorry! That was completely random.

[Wowbagger]

I wanted to reiterate what articulett said: Those who write the most scientifically accepted books about evolution, tend not to describe evolution as random, at all. And, sometimes, they take great pains to show how it is not random. Dawkins' book The Blind Watchmaker is one, for example. Here is an excerpt from its preface:
It is almost as if the human brain were specifically designed to misunderstand Darwinism, and to find it hard to believe. Take, for instance, the issue of 'chance', often dramatized as blind chance. The great majority of people that attack Darwinism leap with almost unseemly eagerness to the mistaken idea that there is nothing other than random chance in it... if you think that Darwinism is tantamount to chance, you'll obviously find it easy to refute Darwinism! One of my tasks will be to destroy this eagerly believed myth that Darwinism is a theory of 'chance'.

It may still be valid to call Evolution "random" in some contexts of the word. But, I feel that it is best the leave the word out, because of all this confusion it causes. It is perfectly possible to describe every aspect of Evolution with other words besides "random".

[jimbob]

Sol, back to my points about chaotic systems.

They are significantly affected by random events.

Doesn't this mean that an asteroid in a chaotic Near Earth Orbit is also going to be significantly affected by random events, possibly to such an extent that it might hit either the Earth or Moon (or neither), with vastly different effects on the course of evolution.

Do you see my point about random factors being important over geological timescales?

Not really, sensitive dependence on initial conditions is not dependant on randomness, it is dependant upon the ability to set back to initial conditions. Like the maps of pendulum direction in rotation, they are chaotic, but if one were able to return the pendulum to the same spot (the matter of precision0 then it would end up rotating the same direction.

I would disagree, because even should you have identical conditions in identical universes, quantum effects would significantly alter the orbits later on. A single atom decaying, or not and eventually the orbits are completely different. Obviously one can't determine the effect of a single quantum event; however these events do not cancel each other out, but cause divergence.

You can assess probabilities of a chaoticly orbiting object being somewhere but if you are talking about far enough into the future, its orbit not only is unpredictible, but as yet undetermined.

In this case I would consider it a significant difference to evolutionary history if an asteroid in a chaotic Near Earth Orbit hit the Moon rather than the Earth.

Even if though some of these events will not be random, the effects will be, as how and which ecological niches are filled will depend on which organism adapts to whichever niche first.

[Dancing David]

I would disagree, because even should you have identical conditions in identical universes, quantum effects would significantly alter the orbits later on. A single atom decaying, or not and eventually the orbits are completely different. Obviously one can't determine the effect of a single quantum event; however these events do not cancel each other out, but cause divergence.

Really? A single atom decaying would make a difference in the orbits of what?

Certainly not a planet or even a small asteroid.

You do know what makes Brownian motion don't you? The bumping of molecules in a glass of water for example. You do know that the average is balanced I hope.

Please demonstrate how this alleged effect would work. The mass of Jupiter is the most important factor of motion in large areas of the solar system.

the issue with orbits is not QM but the sensitive dependance of gravitation.


You can assess probabilities of a chaoticly orbiting object being somewhere but if you are talking about far enough into the future, its orbit not only is unpredictible, but as yet undetermined.

So, that does not mean that it is not causal or deterministic. You misread chaos theory, it is about the chaotic behavior of determined and causal systems. They are not random they are chaotic. there is a huge difference. In the pendulum map it is true that the precision with which you return to the initial condition would allow you to recreate the same event.


In this case I would consider it a significant difference to evolutionary history if an asteroid in a chaotic Near Earth Orbit hit the Moon rather than the Earth.

that is silly. Evolution is the water in the puddle, it will act as it acts, you are hung up on contingent history which means you don't understand it. Contingent history means the actual path of events that led to this current situation.

But here is the deal, evolution or adaption through reproductive success doesn't care.

The comet hits or doesn't hit. So what? Organisms that reproduce effectively will contribute a higher percentage of their selfs to the future mix of the population.

So, the comet hit, that is not evolution, that is a path of contingent history. It would not matter to adaptation through reproductive success if the comet hit 500 million years sooner or later , or if it ever hit at all.

The passing of traits through reproductive success still continues.


Even if though some of these events will not be random, the effects will be, as how and which ecological niches are filled will depend on which organism adapts to whichever niche first.

So?
That is the specifics of contingent history, the reproductive success being related to the traits of future populations doesn't care. You will have 'wedging' even when there is no major change in the enviroment, and it counts as well. Species will change very slowly when there is no radiation to new enviroments and the changes in punctuated equilibria but they will still change.

I am a randomist but only because the whole process is blind, traits will not be chosen for until they are in the right enviroment for the reproductive success to matter. So saying which trait will have which benefit is a crap shoot, it can't be predicted.

However the means by which they benefit reproductive success are causal and deterministic. The success of an organism in reproductive is not totaly random, especialy over large numbers of individuals.

Why do insects have resistance to pesticides? reproductive success, the causal nature of their biology says that they will not die and that they will reproduce. So 'resistance' does not 'develop' instead it is passed on through reproduction.

[Paul C. Anagnostopoulos]

My stamina for this subject are not what they used to be.

~~ Paul

[articulett]

My stamina for this subject are not what they used to be.

~~ Paul

And it's a good thing, Paul. Because, like Kleinman, those who insist on calling evolution random must have the last word.

It will go on until they do. Let me ask you this... do you think anyone could convince Behe not to be so hyperfocused on "randomness" in regards to evolution?

Some battles aren't worth fighting, man. Just warn the new people so they temper their expectations. No doubt, this is just a hair of what Dawkins et. al. must contend with. It's hard to remain in good humor after a while...

[jimbob]

Dancing david, isn't that a bizare feature of chaotic systems.

To accurately predict a chaotic system with no significant differences far enough into the future, you do hit on the stop-popint of needing accuracy down to the quantum level. This is still considered a theoretical limit to how far you can forcast weather system (although probabilistic assessments could be still valid), and applies to other chaotic systems too.

As you say, Juiiter and the Sun are the biggest influences, but chaotic systems still are incredibly sensitive to initial conditions, and the radiation pressure from a decay event will alter these initial conditions. This will take time for the two otherwiswe identical systems to diverge though....

Even forgetting this, my main point was that should evolution be rerun of five identical Earths, there is no reason for the resulting mixes of ecosystems to be similar. It isn't repeatable on geological timescales.

In stable environments, with stable selective pressures randomness is less important, but over the history of life on Earth, randomness has been important.

Maybe it could help explain my position to give some examples where randomness is important and not:

What will happen to a population of baccteris whose population is controlled by antibiotics? They will evolve antibiotic resistance, nonrandom.

What effect would you expect to see on populations of birds on isolated islands with no predators? Some would lose their filight, as this is energy intensive, and nonflying birds would be more frugal. Nonrandom (probably).

What factors were important in the evoluiton of unicellular life into a T Rex? This needs an acceptance that random events have been important.

[cyborg]

This needs an acceptance that random events have been important.

AGAIN:

Does it matter to the description of Evolution?

[jimbob]

It matters to a description of the course of evolution over geological time.

[cyborg]

It matters to a description of the course of evolution over geological time.

That's a no and a fail at understanding the class/instance distinction.

[Dancing David]

Dancing david, isn't that a bizare feature of chaotic systems.

To accurately predict a chaotic system with no significant differences far enough into the future, you do hit on the stop-popint of needing accuracy down to the quantum level. This is still considered a theoretical limit to how far you can forcast weather system (although probabilistic assessments could be still valid), and applies to other chaotic systems too.


The quantum mechanics don't matter regards the weather, there are much larger inputs to the system.

Again chaotic systems are causal and determined. Predictability in science and the clockmaker syndrome are two different critters. Prediction in science are almost always going to be a range, not an exact figure.


As you say, Juiiter and the Sun are the biggest influences, but chaotic systems still are incredibly sensitive to initial conditions, and the radiation pressure from a decay event will alter these initial conditions. This will take time for the two otherwiswe identical systems to diverge though....

You are over interpreting sensitive dependance on initial conditions, show nme where a decay event si going to have an impact on the orbit of a 10,000 kg object. You are dwelling on the QM which is immaterial. the orbits are chaotic, you don't need QM to make them unpredictable.

But you can forecast well enough to get a rocket to Pluto.


Even forgetting this, my main point was that should evolution be rerun of five identical Earths, there is no reason for the resulting mixes of ecosystems to be similar. It isn't repeatable on geological timescales.

So, it is still from the intersection of determined and random events, why the watchmaker hang up?

that is not what random is about. There are pseudo random events which impact the world. So?

the factors that leaed to reproductive success are causal. the players and the enviroment are but the combination is pseudo random.

I don't here any one else saying that evolution should meet the clockmaker criteria except for you.

Strawman?


In stable environments, with stable selective pressures randomness is less important, but over the history of life on Earth, randomness has been important.

Not really, it just creates opportunity for radiation of organisms.

Big whoop, the process is simple, organisms that reproduce have more children than those that don't

That is it, there is no more than that.


Maybe it could help explain my position to give some examples where randomness is important and not:

What will happen to a population of baccteris whose population is controlled by antibiotics? They will evolve antibiotic resistance, nonrandom.

What effect would you expect to see on populations of birds on isolated islands with no predators? Some would lose their filight, as this is energy intensive, and nonflying birds would be more frugal. Nonrandom (probably).

That is what is wrong with certain forms of thought. there are many benefits to flight that have nothing to do with predation at all. So one does not know what to expect. It depends on what factors influence reproduction only.

If there are food sources that can flown to then the flight will remain.


What factors were important in the evoluiton of unicellular life into a T Rex? This needs an acceptance that random events have been important.


Not really, what is so random about reproduction?

[jimbob]

According to wik: pluto's chaotic orbit means that it is unpredictible over tens of millions of years. Maybe some ateroids are in a chaotic NEO, then over 3.8 Gyr of life on earth their orbits would have been unpredictible, as the accuracy required for the initial measurements should be comfortably below the qunantum level.

Discussing weather systems, as they are faster than millions of years...


Even if we had measurements down to the quantum level, we would be limited as to how far into the future we could forcast the weather, because beyond this time, we would need more accurate measures. Beyond this timescale why isn't it random? (I am rusty with many aspects of physics, but was under the impression that it still was the case that beyond a certain time, events at the quantum level are significant). Tens of milllions of years for one chaotic orbit (pluto), but we are talking about a period of 3.8 billion years...

[cyborg]

Beyond this timescale why isn't it random?

Why isn't what? Why isn't anything?

You find nothing odd about the fact you are arguing about the orbital path of Pluto in a discussion about evolution? Just how much don't you want to admit to yourself that you're completely lost on irrelevancies?

[Reality Check]

According to wik: pluto's chaotic orbit means that it is unpredictible over tens of millions of years. Maybe some ateroids are in a chaotic NEO, then over 3.8 Gyr of life on earth their orbits would have been unpredictible, as the accuracy required for the initial measurements should be comfortably below the qunantum level.

Discussing weather systems, as they are faster than millions of years...

Even if we had measurements down to the quantum level, we would be limited as to how far into the future we could forcast the weather, because beyond this time, we would need more accurate measures. Beyond this timescale why isn't it random? (I am rusty with many aspects of physics, but was under the impression that it still was the case that beyond a certain time, events at the quantum level are significant). Tens of milllions of years for one chaotic orbit (pluto), but we are talking about a period of 3.8 billion years...

Note that the chaotic behaviour of orbits are solutions of Newtonian mechanics, i.e. have nothing to do with quantum mechanics.

Quantum effects do not affect the weather. Weather forecasters just need to include classical mechanics.

Quantum effects are subject to quantum decoherence (http://en.wikipedia.org/wiki/Quantum_decoherence) (the interaction of the quantum system with its environment). This quickly turns quantum effects into classical effects. Quantum computing needs the decoherence to be as small as possible and research is ongoing (http://chronicle.uchicago.edu/031120/quantum.shtml) on methods to do this. But this does not happen in nature.

We can see quantum effects in molecules such as bucky-balls (carbon-60) where a 2-slit experiment shows interference fringes. Anything much larger than this is a classical object exhibiting classical effects.

[articulett]

See, isn't it weird... --he's not interested in describing evolution clearly--he's interested in calling evolution "random".

[Reality Check]

What factors were important in the evoluiton of unicellular life into a T Rex? This needs an acceptance that random events have been important.

Variability in inheritance.
Natural selection.This is of course evolution. There are some random events in the variability in inheritance. This is overwhelmed by the non-randomness of natural selection.

[mijopaalmc]

See, isn't it weird... --he's not interested in describing evolution clearly--he's interested in calling evolution "random".

The same could be said about describing evolution as non-random even though all of its component has the possibility of being random. Orderly adaptation to the environment does not imply that natural selection or evolution is non-random.

[cyborg]

The same could be said about describing X as non-random even though all of its component has the possibility of being random.

Please give an X where this does not apply in mijo world. You know, as you've been asked to do so repeatedly.

[articulett]

Variability in inheritance.
Natural selection.This is of course evolution. There are some random events in the variability in inheritance. This is overwhelmed by the non-randomness of natural selection.

He and Mijo have been told as much for well over a year... and gotten the best quotes from peer reviewed experts on the topic. But they think they are smarter than the experts... and they absolutely must have the last word and the last word must be that "evolution is random" or if they are feeling generous "evolution is not nonrandom". It's bizarre, but unchangeable. They would rather believe that scientists think that evolution is random than to be clear.

And they will reward you with insults for your careful replies. They have no interest on current understanding on this topic... their only interest is proving themselves right in their head. If you engage them, keep all expectations low... and be prepared to find them maddeningly nonsensical.

[Earthborn]

Quantum effects do not affect the weather. Weather forecasters just need to include classical mechanics.Weather forecasters just need to include classical mechanics to model the weather for up to few days into the future, but you may have noticed that Jimbob is talking about extremely long timeframes. Timeframes that are so long that they cannot be accurately modelled as they become chaotic. Smaller and smaller factors start to interfere with the results. In medium timeframes things like butterflies flapping their wings start would need to be considered if you want to make the model predict the weather to any degree of accuracy, which of course makes the model too complex to handle. In truly long timeframes, lets say trying to predict the weather for a specific day a million years in the future, taking all the butterflies into consideration will not be enough. Would quantum fluctuations need to be considered as well? I would think so.

[Earthborn]

I wanted to reiterate what articulett said: Those who write the most scientifically accepted books about evolution, tend not to describe evolution as random, at all.Articulett also claims that by doing so, they are more effective at explaining evolutionary theory to people who have no prior understanding or belief in it. Perhaps this is true, but I have not heard an argument that convinces me that it is.

And, sometimes, they take great pains to show how it is not random. Dawkins' book The Blind Watchmaker is one, for example. Here is an excerpt from its preface:I agree with Dawkins that it is a mistaken idea to conceptualise evolution as having "nothing other than random chance" and I also agree that Darwinism is not a theory of chance. I just don't think it is unfair to look at the entire history of the evolution of life and say that it has been influenced in many ways by random events, great and small.

It is perfectly possible to describe every aspect of Evolution with other words besides "random".Perhaps, but I don't think "unconsciously indifferent" is it. "Probabilistic" or "stochastic" are probably better, but have the additional problem that the average layperson probably has no understanding of those words at all.

[Dancing David]

According to wik: pluto's chaotic orbit means that it is unpredictible over tens of millions of years.

That is a really long time, why does it matter? You can be accurate enough to send a probe there is a human life time. Causal and detrministics does not mean, set upon a rail track moving at a constant rate and speed.

So a system may not be predictable, a chaotic system is causal and deterministic, it is not random.

Oganisms and the genome can not predict the future. So what traits will have benefit in which future enviromenets is unknown, that does not mean that the process that leads to reproductive success is random. That means the setting and players are somewhat unpredictable.

Why is the ability to predict the future important? It is not what science means when it says predict the behavior of a system. In fact it is acceptable to say "It will fall within this area."

Predictability doesn't matter to reproductive success. It isn't going somewhere it is just going.

Maybe some ateroids are in a chaotic NEO, then over 3.8 Gyr of life on earth their orbits would have been unpredictible, as the accuracy required for the initial measurements should be comfortably below the qunantum level.

You really don't get it do you?

It has nothing to do with QM, the orbits are effected by gravitation, and that is a gross scale event.
It is causal, deterministic and chaotic (within limits), it is not random. Unpredictable does not mean random.


Discussing weather systems, as they are faster than millions of years...


Even if we had measurements down to the quantum level, we would be limited as to how far into the future we could forcast the weather, because beyond this time, we would need more accurate measures. Beyond this timescale why isn't it random?

Because it is deterministic, just because we can't accurately model the parameters does not sudenly *poofo* make it random.

It makes it beyond our ability to model.

Omniscence is for made up creatures beyond the real world.

(I am rusty with many aspects of physics, but was under the impression that it still was the case that beyond a certain time, events at the quantum level are significant).

Nope, that is just not tue, the radiation from the sun comes in photons, but the energy does not sudenly jump to the other side of the planet. The weather is a gross system, QM pertains to very small events.

Tens of milllions of years for one chaotic orbit (pluto), but we are talking about a period of 3.8 billion years...


So you have 50 significant gravitational forces, it only takes three bodies to make a chaotic system.

Chaotic systemsn are detrministic and causal they are not random.

[Reality Check]

Weather forecasters just need to include classical mechanics to model the weather for up to few days into the future, but you may have noticed that Jimbob is talking about extremely long timeframes. Timeframes that are so long that they cannot be accurately modelled as they become chaotic. Smaller and smaller factors start to interfere with the results. In medium timeframes things like butterflies flapping their wings start would need to be considered if you want to make the model predict the weather to any degree of accuracy, which of course makes the model too complex to handle. In truly long timeframes, lets say trying to predict the weather for a specific day a million years in the future, taking all the butterflies into consideration will not be enough. Would quantum fluctuations need to be considered as well? I would think so.

Actually no - the chaotic solutions come out of classical mechanics, not quantum mechanics. Just ask yourself whether geologists who often work on scales of 100's of millions of years have to consider quantum mechanics?

[Dancing David]

Weather forecasters just need to include classical mechanics to model the weather for up to few days into the future, but you may have noticed that Jimbob is talking about extremely long timeframes. Timeframes that are so long that they cannot be accurately modelled as they become chaotic. Smaller and smaller factors start to interfere with the results. In medium timeframes things like butterflies flapping their wings start would need to be considered if you want to make the model predict the weather to any degree of accuracy, which of course makes the model too complex to handle. In truly long timeframes, lets say trying to predict the weather for a specific day a million years in the future, taking all the butterflies into consideration will not be enough. Would quantum fluctuations need to be considered as well? I would think so.


I don't know EB, those things might matter but when the huge amount of energy from the sun hits the soild ground, plants or ocean and creates updrafts or evaporation, then the flap of a butterfly, will just sort of not matter.

There is no mathematical proof of the butterfly effect. It is an allusion. ( I love butterflies, but I see them sail in the wind. It is what they do. They don't make the wind. Not even if you got them all together, then you would have a brownian motion thing.
(I love watching butterflys stall glide, especialy the monarchs in the fall when they rise up way high in the sky.)

[Dancing David]

I just don't think it is unfair to look at the entire history of the evolution of life and say that it has been influenced in many ways by random events, great and small.




Yes, the history of evolution. That is not the same as the process of evolution, the fall of a mountain is the history of gravity. It is not the process we call gravity?

[quixotecoyote]

Yes, the history of evolution. That is not the same as the process of evolution, the fall of a mountain is the history of gravity. It is not the process we call gravity?

That would be more plate tectonics/vulcanology than gravity. Analogy fails.

[Wowbagger]

Perhaps, but I don't think "unconsciously indifferent" is it. "Probabilistic" or "stochastic" are probably better, but have the additional problem that the average layperson probably has no understanding of those words at all. How about "directionless"? I think someone suggested that substitute, at some point.

[jimbob]

It is a dogression, but chaotic systems are hypersentistive tio initial conditions so that a classical treatment requires accuracy that doesnt actually exist.

Here (http://physicaplus.org.il/articles2/barrow_eng.html) is a discussion about a very simple system (from the Israel physical society)

You can apply this rule to snooker balls as well as molecules. One knows from bitter experience that snooker or pool exhibits sensitive dependence on initial conditions: a slight miscue of the cue-ball produces a big miss! If the balls are bouncing around a frictionless snooker table in a perfect vacuum (otherwise they will just stop moving after one or two collisions) then we might typically have d=1 metre and r=3 cm, so our map is qn+1 = 3qn. The growth in recoil angle uncertainty in the trajectory of a ball as it bounces off other balls is therefore pretty dramatic. In fact, if you hit the ball as accurately as Heisenberg's quantum Uncertainty Principle allows any physical process to be determined by observation, then only about 12 collisions are needed to amplify this uncertainty up to more than 90 degrees!

Twenty-four collisions ahead, and there are twelve sets of collisons where the accuracy required would be beyind the uncertainty principle.

Why is it wrong to describe the behaviour of the snooker ball that far ahead as random? Not just unpredictible, but random.

You would be wrong to describe the behaviour three collisions ahead as random, but twenty four, or thirteen collisions ahead?

This is a simple system but it does involve classical mechanics in a chaotic system, and thus for far-enough ahead is random.

Weather systems, which affect individual organisms is similarly a chaotic system, so I cant see why this behaviour far enough ahead isn't truely random.

Indeed I can't see why any choatic system, far enough ahead, isn't random.

[mijopaalmc]

jimbob-

If I may be so bold to speculate, I seems that the most common response to your questions about chaos and randomness would be "your description makes everything random". While that is not necessarily my opinion, I would like to point out that your focus on the divergence in chaotic system obscure an important characteristic of evolution and of random system, namely their convergence to optima over long periods of time. I am not saying that chaotic systems cannot describe evolution, but it is not at all clear how the phenomenology of evolution emerges from your descriptions of chaotic systems

[Reality Check]

It is a dogression, but chaotic systems are hypersentistive tio initial conditions so that a classical treatment requires accuracy that doesnt actually exist.
Here (http://physicaplus.org.il/articles2/barrow_eng.html) is a discussion about a very simple system (from the Israel physical society)
...snip...
Indeed I can't see why any choatic system, far enough ahead, isn't random.


Look further on in the article that you cite:
Chaotic systems can have stable, predictable, long-term, average behaviours. However, it is often very difficult to predict when they will. You usually just have to explore and discover whether they do or not.


I suggest that you read the Wikipedia article on chaos theory (http://en.wikipedia.org/wiki/Chaos_theory):

Chaotic behavior has been observed in the laboratory in a variety of systems including electrical circuits, lasers, oscillating chemical reactions, fluid dynamics, and mechanical and magneto-mechanical devices. Observations of chaotic behaviour in nature include the dynamics of satellites in the solar system, the time evolution of the magnetic field of celestial bodies, population growth in ecology, the dynamics of the action potentials in neurons, and molecular vibrations. Everyday examples of chaotic systems include weather and climate. There is some controversy over the existence of chaotic dynamics in the plate tectonics and in economics.

Systems that exhibit mathematical chaos are deterministic and thus orderly in some sense; this technical use of the word chaos is at odds with common parlance, which suggests complete disorder. A related field of physics called quantum chaos theory studies systems that follow the laws of quantum mechanics. Recently, another field, called relativistic chaos, has emerged to describe systems that follow the laws of general relativity.

As well as being orderly in the sense of being deterministic, chaotic systems usually have well defined statistics. For example, the Lorenz system pictured is chaotic, but has a clearly defined structure. Bounded chaos is a useful term for describing models of disorder.

[sol invictus]

Why is it wrong to describe the behaviour of the snooker ball that far ahead as random? Not just unpredictible, but random.

First of all, you are correct that quantum fluctuations can have large effects on chaotic systems. ANY fluctuation, no matter how small, can have a large effect on a chaotic system - that's by definition of chaos. So forget about QM, it's irrelevant - chaotic systems are fundamentally unpredictable, and it is pointless to differentiate between "true randomness" and unpredictability (except as an intellectual exercise). The distinction has no operational meaning.

I introduced these ideas weeks (months?) ago into these threads. My point was that since the world is quantum and chaotic, and since all systems in the world are coupled, everything is random and unpredictable if your definition of those terms is too rigid (like mijo's before we changed his mind). But even though the earth may be destroyed by a giant asteroid tomorrow, we still (correctly) regard many things in our lives as predictable.

Weather is chaotic, but it's always warmer in summer than winter. Evolution took place in a chaotic environment, but it predictably lead from prokaryotes to more complex and diverse life. Flames are chaotic, but they always burn you. Smoke detectors rely directly on random decays, but they are very reliable.

[Belz...]

Not really, what is so random about reproduction?

Well, according to Mijo's definition, since your girlfriend may or may not have a headache that night, it becomes a probability distribution which makes the act of lovemaking completely random!!

[Belz...]

It is a dogression, but chaotic systems are hypersentistive tio initial conditions so that a classical treatment requires accuracy that doesnt actually exist.

EVERYTHING is sensitive to initial conditions. That has nothing to do with randomness.

I seems that the most common response to your questions about chaos and randomness would be "your description makes everything random".

No, YOUR definition makes everything random as everybody in this thread but you has noted.

[Belz...]

First of all, you are correct that quantum fluctuations can have large effects on chaotic systems.

I'm aware they could have an effect, but a large one ? How ?

[Dancing David]

That would be more plate tectonics/vulcanology than gravity. Analogy fails.


Sure, it was a metaphor, I should have said , erode. History of water , wear and gravity.

[sol invictus]

I'm aware they could have an effect, but a large one ? How ?

The definition of a chaotic system is that if you change the initial conditions slightly, the system's state diverges exponentially with time from where it would have been had you not changed the initial conditions. The rate of that divergence depends on the size of the initial deviation and a system-dependent parameter. But after enough time the divergence is always large regardless of the size of the initial perturbation, and the time required grows only very slowly (logarithmically) as you make the initial perturbation smaller.

jimbob's example of the billiard balls was a good one - the claim was that after 12 billiard ball collisions, the Heisenberg uncertainty in the initial positions of the balls translates into total uncertainty in their positions. I haven't checked the number 12, but even if it's wrong the correct answer won't be very much larger.

[Dancing David]

It is a dogression, but chaotic systems are hypersentistive tio initial conditions so that a classical treatment requires accuracy that doesnt actually exist.

Here (http://physicaplus.org.il/articles2/barrow_eng.html) is a discussion about a very simple system (from the Israel physical society)



Twenty-four collisions ahead, and there are twelve sets of collisons where the accuracy required would be beyind the uncertainty principle.

That is different than saying QM has an impact on the out come.

You haven't demonstrated that the outcome is dependant on the uneven distribution of quantum events. The gross scale interactions are the significant ones. The even distribution of QM events will strill occur.

i want your demonstration that a partcile being in postion P of a probable distribution is electron shell S is going to have significant impact on m and v momentum of a snooker ball at some particular point.

You haven't shown that at all.


Why is it wrong to describe the behaviour of the snooker ball that far ahead as random? Not just unpredictible, but random.

Why don't you demonstrate your theory, that unpredictable equals random. Your usage , your defense.


You would be wrong to describe the behaviour three collisions ahead as random, but twenty four, or thirteen collisions ahead?

This is a simple system but it does involve classical mechanics in a chaotic system, and thus for far-enough ahead is random.

Unpredictable is not random.

Chaotic systems are determined and causal.


Weather systems, which affect individual organisms is similarly a chaotic system, so I cant see why this behaviour far enough ahead isn't truely random.

Indeed I can't see why any choatic system, far enough ahead, isn't random.


Okay, so that is how you want to use the word. What meaningful purpose comes from saying that unpredictable means the same as random.

Does it provide you comfort? Does it make communication clearer or is it just some bizzare point of semantics.

I can also say that all biological organisms are dog, does that mean anything?

ETA:

Sol agrees with you Jimbob, but I won't edit out what i just said. I will continue to think about why I feel it doesn't matter and see if I can restate my thought.

[sol invictus]

ETA:

Sol agrees with you Jimbob, but I won't edit out what i just said. I will continue to think about why I feel it doesn't matter and see if I can restate my thought.

It's OK to disagree with me! :) Sometimes I'm even wrong :jaw-dropp.

I think QM events can strongly affect chaotic systems after relatively short amounts of time. I'm pretty sure 99% of physicists would agree with me.

I don't think it's useful to distinguish between "random" and "unpredictable" when we're discussing physical processes. I'm not sure how many physicists would agree with me on that (although I think I could convince them).

But none of that prevents us from predicting with extremely high confidence that July in Saskatoon will be warmer than January in Saskatoon. As they say - "weather is chaotic, but climate is predictable" (or something along those lines). As for evolution, it has both weather-like and climate-like aspects.

[Walter Wayne]

I wanted to reiterate what articulett said: Those who write the most scientifically accepted books about evolution, tend not to describe evolution as random, at all. And, sometimes, they take great pains to show how it is not random. Dawkins' book The Blind Watchmaker is one, for example. Here is an excerpt from its preface:
It is almost as if the human brain were specifically designed to misunderstand Darwinism, and to find it hard to believe. Take, for instance, the issue of 'chance', often dramatized as blind chance. The great majority of people that attack Darwinism leap with almost unseemly eagerness to the mistaken idea that there is nothing other than random chance in it... if you think that Darwinism is tantamount to chance, you'll obviously find it easy to refute Darwinism! One of my tasks will be to destroy this eagerly believed myth that Darwinism is a theory of 'chance'.

It may still be valid to call Evolution "random" in some contexts of the word. But, I feel that it is best the leave the word out, because of all this confusion it causes. It is perfectly possible to describe every aspect of Evolution with other words besides "random".
I agree the word random can be avoided in explaining evolution. But it is because of the confusion the word creates that I think the term must be used in evolution's teaching. Students will inevitably come across the term, most likely in a debate with a creationist. With descriptions of natural selection being laden with terms that don't imply certainty ("more likely", "tends to", ...) and mutation being "blind", how will our hypothetical student respond to a challenge based around the word random. I am guessing he would be ill equiped to deal with it.

I also take issue with describing evolution like the "experts" do. The newspapers articles cited claiming evolution is "not-random" actually link to papers that don't say that. This isn't an area that has no debate in it, but one can get the impression that there is only one expert opinion from the discussions.

"Understanding" is being painted as agreeing with a few specific experts (the most prominent lay writers). One may hold an opinion on what "level" natural selection works on, but if one teaches only "gene centered evolution" one is not giving students an understanding of the field. Thus understanding becomes identified with parrotting back one particular view, rather than knowledge of the subject. In another thread, when I disagreed with someone's characterization of natural selection being what "builds" the complexity, the person replied that what they meant was that selection was a sort of rachet for complexity. Now it so happens, that "rachet" is the precise metaphor that Dawkins uses. Should I then believe that the person actually understands Dawkins's metaphor, or that they interpreted in wrongly and are thus unable to express it in their own words?

Walt

[jimbob]

It's OK to disagree with me! :) Sometimes I'm even wrong :jaw-dropp.

I think QM events can strongly affect chaotic systems after relatively short amounts of time. I'm pretty sure 99% of physicists would agree with me.

I don't think it's useful to distinguish between "random" and "unpredictable" when we're discussing physical processes. I'm not sure how many physicists would agree with me on that (although I think I could convince them).

Surprisingly, I'd agree with that, but several people have been proposing "Laplacian Determinism" (http://www.sfu.ca/philosophy/swartz/freewill1.htm#laplace), i.e.

An intellect which at any given moment knew all the forces that animate Nature and the mutual positions of the beings that comprise it, if this intellect were vast enough to submit its data to analysis, could condense into a single formula the movement of the greatest bodies of the universe and that of the lightest atom: for such an intellect nothing could be uncertain; and the future just like the past would be present before our eyes.

In such a I have been reading their argument an being that evolution is completely deterministic, so that if we were able to measure the initial conditions accurately enough, the evolutionary outcomes would be always the same.

I started out thinking there was simply a semantic difference, then came to the conclusion that the difference was more fundamental, hence my above reference to Laplacian Determinism.

The following post for example, with most of it hidden for brevity:

Sigh. I am going to have to point out the counter-intuitive nature of infinities again?

Jimbob - yet again I must ask: do you get the difference between using probabilities to model a system where the probabilities stand in effectively for a set of complexly interacting variables?

Consider the evolutionary models below:

Model A will be much like Ev - we will have a pool of creatures with a target genome. Mutations to the target pool occur at some rate and distributed with probabilities. Survival is dictated by how well the organisms score against the target genome.

Model B will extend Ev - we now introduce the concept of a target functionality. Instead of being scored against a genome we score against the ability for a given organism to act like the functional target. We will now have a notion of how the genotype effects phenotypes.

Model C extends model B to introduce the notion of competition. Instead of selecting based on a simple score we now provide a physical environment for our phenotypes to interact in. We have a more 'natural' sense of survival in this instance - now having to exist in a physical space organisms will have to contend with the thing you had a problem with earlier. Essentially being, "in the wrong place at the wrong time."

Now we could model some of the new things we will see occur in model C in models A and B using probabilities to represent the idea of there being "bad luck" in one's positioning.

Now, as we extend model C with new aspects that make the simulation more akin to what we see in the real world clearly we are increasing the complexity of the model. Now do you see why this increase in complexity would lead to the appearance of it being random? It's because the more variables you have - the richer your model - the more difficult it is to predict the behaviour of the model even if it is deterministic.

If you think it is always easy to predict how a deterministic model will behave then I would have to ask why you would think that would be so. If you get that the difficulty as to how to predict its behaviour increases with the number of variables in the model and how aperiodic it is then it is only a short step to see that the more one increases the number of variables the more akin it is to seeming to be random in nature. (And in the infinite case it is mathematically equivalent).

So, is the randomness in the model a reflection of how things are actually occurring or just the sum total of our ignorance about the variables involved in giving rise to it?

Can you see why for a sufficiently rich model probabilities would not have to be involved?



But none of that prevents us from predicting with extremely high confidence that July in Saskatoon will be warmer than January in Saskatoon. As they say - "weather is chaotic, but climate is predictable" (or something along those lines). As for evolution, it has both weather-like and climate-like aspects.


I have already agreed with your description:

I would argue that selection is probabilistic ("random" gust of wind etc affecting survival). However, we can still see how different traits affect the odds of producing reproducing offspring. I think a valid analogy might be between weather and climate. The individual slection event might be "random" but the efffect over a large enough population means that some beneficial traits will propagate.

Doing the sums, I would conclude that most "beneficial" traits that arise probably don't survive more than one generation.

This is because the odds are against any individual organism reproducing, for virtually any species (possibly except our own currently). For example, the Barn Owl population is roughly stable, but it tends to have a clutch sizes of about 3-7 and sometimes breed twice a year, and live for 1-5 years in the wild (25 years in captivity). Of the total brood size over the lifetime of the pair, on average only two offspring will breed if the population is stable.

Say this equates to 5 clutches, of 4 birds. Then there is 90% chance of any individual not breeding, and a 10% chance of it breeding. To get an evens chance of a particular trait making it past the first individual, it would need to confer a 500% advantage compared to its peers...

However we are dealing with big numbers, and some (enough) advantageous traits will survive and get passed on...

Disadvantageous traits are almost certain to vanish very quickly. In the barn owl example, a neutral trait already has a 90% chance of not getting passed on.

[cyborg]

In such a I have been reading their argument an being that evolution is completely deterministic, so that if we were able to measure the initial conditions accurately enough, the evolutionary outcomes would be always the same.

If everything is the same everything is the same - even you have to acknowledge this.

QM is a Red Herring - it's an appeal to the argument, "yeah, but in reality if you wind back the clock because QM is random not everything can be the same, hence you can't ignore the impact of that on evolution."

Which makes a mockery of the concept of modelling phenomena as a class of events.

[jimbob]

So you still stand by your view that:

Can you see why for a sufficiently rich model probabilities would not have to be involved?

[cyborg]

Yes. If I replace the die roll with a list of numbers I have a deterministic set of data - irrespective of whether or not the list of numbers has maximum entropy.

[Wowbagger]

I agree the word random can be avoided in explaining evolution. But it is because of the confusion the word creates that I think the term must be used in evolution's teaching. Students will inevitably come across the term, most likely in a debate with a creationist. With descriptions of natural selection being laden with terms that don't imply certainty ("more likely", "tends to", ...) and mutation being "blind", how will our hypothetical student respond to a challenge based around the word random. I am guessing he would be ill equiped to deal with it. We can teach them that there are valid and invalid usage of the word "random", similar to my OP. Of course, if my OP is wrong about something, I hope the education professionals would be able to put together something more accurate.

We don't need the R-word to explain the process to them, but I agree that, in order to be equipped with challenges (in this case, semantic ones), they should also be taught some of the proper rebuttals.

I also take issue with describing evolution like the "experts" do. The newspapers articles cited claiming evolution is "not-random" actually link to papers that don't say that. This isn't an area that has no debate in it, but one can get the impression that there is only one expert opinion from the discussions. I disagree. I think the newspapers should learn to describe science the way experts do it. Perhaps Dawkins-style analogies would not be a bad comprimise, though, if they are carefully constructed.

"Understanding" is being painted as agreeing with a few specific experts (the most prominent lay writers). One may hold an opinion on what "level" natural selection works on, but if one teaches only "gene centered evolution" one is not giving students an understanding of the field. Thus understanding becomes identified with parrotting back one particular view, rather than knowledge of the subject. This has nothing to do with the topic (which is more steeped in semantics), but I do basically agree with it. Comprehensive understanding of the field, is better than focusing solely on some narrow aspect of it.

This thread has now accumulated over 7,000 views. Is it really that popular?!!

[mijopaalmc]

If everything is the same everything is the same - even you have to acknowledge this.

QM is a Red Herring - it's an appeal to the argument, "yeah, but in reality if you wind back the clock because QM is random not everything can be the same, hence you can't ignore the impact of that on evolution."

Which makes a mockery of the concept of modelling phenomena as a class of events.

You are completely missing the point. Quantum randomness has an orderly classical (or semiclassical) limit. Quantum randomness therefore stands as an example of a random process that has orderly long-term and large-scale behavior and the example does not rest upon everything's ultimate origin in quantum mechanics.

[cyborg]

You are completely missing the point.

No, it would seem you are.

Quantum randomness has an orderly classical (or semiclassical) limit. Quantum randomness therefore stands as an example of a random process that has orderly long-term and large-scale behavior and the example does not rest upon everything's ultimate origin in quantum mechanics.

In other words: the whole QM discussion is largely irrelevant to how we talk about evolution. It is a large red fish.

[mijopaalmc]

In other words: the whole QM discussion is largely irrelevant to how we talk about evolution. It is a large red fish.

Except that it is an example of a random process that has orderly long-term and large-scale behavior, demonstrating that there need be no underlying deterministic framework for evolution by natural selection to display the phenomenology it does.

[Reality Check]

Except that it is an example of a random process that has orderly long-term and large-scale behavior, demonstrating that there need be no underlying deterministic framework for evolution by natural selection to display the phenomenology it does.
This is the inverse of quantum mechanics: QM is a deterministic process (see the Schrödinger equation (http://en.wikipedia.org/wiki/Schr%C3%B6dinger_equation)) where a measurement has an expectation value. It is the measurement that has a probability and I think that you could call that the "random" part of QM.
If you want to use QM as an analogy for evolution (or demonstration of evolution) then there must be the equivalent of the Schrödinger equation in evolution, i.e. by your argument evolution has a "underlying deterministic framework".

[mijopaalmc]

This is the inverse of quantum mechanics: QM is a deterministic process (see the Schrödinger equation (http://en.wikipedia.org/wiki/Schr%C3%B6dinger_equation)) where a measurement has an expectation value. It is the measurement that has a probability and I think that you could call that the "random" part of QM.
If you want to use QM as an analogy for evolution (or demonstration of evolution) then there must be the equivalent of the Schrödinger equation in evolution, i.e. by your argument evolution has a "underlying deterministic framework".

The quantum mechanical wave function is a random variable as it describes the probability amplitudes at different points in space. Since the Schrödinger equation takes the wave function its argument, it is a probabilistic equation.

[sol invictus]

Surprisingly, I'd agree with that, but several people have been proposing "Laplacian Determinism" (http://www.sfu.ca/philosophy/swartz/freewill1.htm#laplace), i.e.
An intellect which at any given moment knew all the forces that animate Nature and the mutual positions of the beings that comprise it, if this intellect were vast enough to submit its data to analysis, could condense into a single formula the movement of the greatest bodies of the universe and that of the lightest atom: for such an intellect nothing could be uncertain; and the future just like the past would be present before our eyes.


Interesting. I'm pretty sure I can prove on the basis of physical law that such an "intellect" is literally impossible.

[sol invictus]

The quantum mechanical wave function is a random variable as it describes the probability amplitudes at different points in space.

Wrong. The wavefunction is a probability distribution (or really, the square root of one), not a random variable. All these posts and you can't even get the basic mathematical terminology right?

The time evolution of the wavefunction is totally deterministic, as it obeys a differential equation.

[Reality Check]

The quantum mechanical wave function is a random variable as it describes the probability amplitudes at different points in space. Since the Schrödinger equation takes the wave function its argument, it is a probabilistic equation.
The wave function in the Schrödinger equation is interpreted as a probability amplitude because when we take a measurement it enters as a magnitude squared. However the wave function changes in time according to the deterministic Schrödinger equation.

[mijopaalmc]

Wrong. The wavefunction is a probability distribution (or really, the square root of one), not a random variable. All these posts and you can't even get the basic mathematical terminology right?

The time evolution of the wavefunction is totally deterministic, as it obeys a differential equation.

Any measurable function of a random variable (which is described by a probability distribution is itself an random variable. The wave function and the its square are therefore both random variables.

[jimbob]

Surprisingly, I'd agree with that, but several people have been proposing "Laplacian Determinism" (http://www.sfu.ca/philosophy/swartz/freewill1.htm#laplace), i.e.
An intellect which at any given moment knew all the forces that animate Nature and the mutual positions of the beings that comprise it, if this intellect were vast enough to submit its data to analysis, could condense into a single formula the movement of the greatest bodies of the universe and that of the lightest atom: for such an intellect nothing could be uncertain; and the future just like the past would be present before our eyes.


Interesting. I'm pretty sure I can prove on the basis of physical law that such an "intellect" is literally impossible.

Of course Laplace wrote that in 1814, and even then I think this hypothetical intellect would have to have been larger than and outside the universe.

I have always understood it as similar to the statement, "God does not play dice", which I have understood was supporting the idea of a completely determanistic (and predetermined) universe, where any (pseudo)random events or behaviour only look random because of incomplete information.

[Reality Check]

Any measurable function of a random variable (which is described by a probability distribution is itself an random variable. The wave function and the its square are therefore both random variables.


Here is the Wikipedia article on wave functions (http://en.wikipedia.org/wiki/Wave_function). If you read it you will see that a wave function is not defined using random variables. For example
The wave function for a particle in 1 spacial dimension is a function of x
The wave function for a particle in three spacial dimensions is a function of x, y and z.The outputs of a wave function are complex numbers that are interpreted as probability amplitudes (the Copenhagen interpretation (http://en.wikipedia.org/wiki/Copenhagen_interpretation)).

[mijopaalmc]

Here is the Wikipedia article on wave functions (http://en.wikipedia.org/wiki/Wave_function). If you read it you will see that a wave function is not defined using random variables. For example
The wave function for a particle in 1 spacial dimension is a function of x
The wave function for a particle in three spacial dimensions is a function of x, y and z.The outputs of a wave function are complex numbers that are interpreted as probability amplitudes (the Copenhagen interpretation (http://en.wikipedia.org/wiki/Copenhagen_interpretation)).

I read the article before I posted.

It's really quite simple: if something is described by a probability distribution it is a random variable. This doesn't mean it can necessarily take on any value with any probability, because that is not how a random variable is defined.

[Reality Check]

I read the article before I posted.

It's really quite simple: if something is described by a probability distribution it is a random variable. This doesn't mean it can necessarily take on any value with any probability, because that is not how a random variable is defined.

It's really quite simple: if something is not described by a probability distribution it is not a random variable.

Wave functions are functions of the phase space under consideration, e.g. the wave function for a particle in three spacial dimensions is a function of x , y and z. X, y and z are the spacial dimensions. They are not probability distributions. Therefore the wave function is not a described by probability distributions and is not a random variable.

A basic definition of a random variable is a function that maps events from a random process into numbers. The Schrödinger equation is not a random process - it is a partial second differential equation and deterministic.

An analogy would be the Gaussian function. It is definitely deterministic. But you can use it to represent a probability distribution. Does that make the Gaussian function a random variable?

[sol invictus]

Any measurable function of a random variable (which is described by a probability distribution is itself an random variable. The wave function and the its square are therefore both random variables.

The wavefunction is not a function of a random variable - you're very very confused.

After kicking and screaming about this nonsense for so many months (or is it years?) you still don't understand even the first and most basic probability-theoretic definitions?

[sol invictus]

Of course Laplace wrote that in 1814, and even then I think this hypothetical intellect would have to have been larger than and outside the universe.

I have always understood it as similar to the statement, "God does not play dice", which I have understood was supporting the idea of a completely determanistic (and predetermined) universe, where any (pseudo)random events or behaviour only look random because of incomplete information.

If the intellect doesn't obey the usual laws of physics that statement is perfectly consistent in a quantum world as well. Deterministic non-local hidden variable theories can explain all of QM (but they are non-local).

If the intellect does obey the laws of physics - e.g. if it's a big computer with all that data - I think I can prove it impossible, even in a classical world, because of chaos.

[Belz...]

You are completely missing the point. Quantum randomness has an orderly classical (or semiclassical) limit.

Does it ?

[articulett]

The wavefunction is not a function of a random variable - you're very very confused.

After kicking and screaming about this nonsense for so many months (or is it years?) you still don't understand even the first and most basic probability-theoretic definitions?

Bingo.

And it's been over a year since he started a thread supposedly seeking to understand how evolution can be described as non-random.

Sad, but true. He and Jimbob were making the same arguments then, btw.

[jimbob]

If the intellect doesn't obey the usual laws of physics that statement is perfectly consistent in a quantum world as well. Deterministic non-local hidden variable theories can explain all of QM (but they are non-local).

If the intellect does obey the laws of physics - e.g. if it's a big computer with all that data - I think I can prove it impossible, even in a classical world, because of chaos.

Agreed and, if it were within the universe, it would have to have a perfect model of itself.

Do you see my point that some people are arguing that there is no randomness in the system of natural selection, and that if we made an accurate enough model, we could predict all selective events (with 100% certainty). In other words I believe their contention is that randomness in natural selection is simply an illusion due to inadequate information.

Hey, the only difference I wanted to make at the start was that organisms with beneficial traits tend to reproduce, whilst those with adverse traits tend to not reproduce. This was apparently confusing compared to saying that organisms with beneficial traits reproduce whilst those with adverse traits don't.

[mijopaalmc]

The wavefunction is not a function of a random variable - you're very very confused.

After kicking and screaming about this nonsense for so many months (or is it years?) you still don't understand even the first and most basic probability-theoretic definitions?

Actually I understand the basic probability-theoretic definitions much better than you do. The wave function (or more properly the square of its absolute value) take spatial-temporal coordinates and maps the to a set of probabilities, making it a random variable by definition.

[mijopaalmc]

Does it ?

Yes (http://physics.bgu.ac.il/~stotland/ARCHIVE/qcc_JPA.pdf)

[sol invictus]

Actually I understand the basic probability-theoretic definitions much better than you do.

If so, you're certainly not demonstrating it.

The wave function (or more properly the square of its absolute value) take spatial-temporal coordinates and maps the to a set of probabilities, making it a random variable by definition.

Go back and re-read your textbook.

At least in the Copenhagen interpretation of QM, the wavefunction squared is a probability distribution on a random variable (the position of a particle if we are discussing the wave function in the position basis). It is not a random variable itself, nor does it depend on one. It is a function of position and time - which are coordinates, not variables.

[cyborg]

Do you see my point that some people are arguing that there is no randomness in the system of natural selection, and that if we made an accurate enough model, we could predict all selective events (with 100% certainty).

What is it about "if everything is the same everything is the same," exactly that is particularly hard to understand?

[jimbob]

Because the universe isn't like this.

As far as I understand it, the best interpretation about quantum uncertainty isn't just that we can't know both a particle's position and momentum beyond with an accuracy more than Hbar/2, but that the universe itself doesn't "know". It isn't decided, i.e. it is random.

In other words, should we have five identical universes when everything is the same at one point in time, they would differ later on.

[cyborg]

In other words, should we have five identical universes when everything is the same at one point in time, they would differ later on.

I'll make it really simple for you.

Universe Ux

Events {A, B}

U1: AA
U2: AB
U3: BA
U4: BB

Now, give me a U5 that IS NOT the same as U1-4 after two events.

Also please tell me under what circumstances would the sequence of A/B events would be inadequate to describe the sequence of A/B events in any arbitrary Universe.

What is it about "if everything is the same everything is the same," exactly that is particularly hard to understand?

[jimbob]

I am not sure that I understand you, unless you are saying that if identical cstarting conditions included some non-physical reason that made fuure random events happen the same in the future.

With the snooker ball example, is the motion of the ball after twenty collisions predetermined at the time of the first collision?

[cyborg]

I am not sure that I understand you

The same event is the same event.

[jimbob]

So is the motion of the snookerball after its twentieth collison predetermined at the time of the first collision?

[cyborg]

That's a Red Herring.

It doesn't matter. The billard balls can only respond to the unfolding situation. That doesn't make their response random. I fail to see why you can't make this distinction.

The response to an event is determined. The occurrence of the event is not. However as the response is determined under indentical sets of events indentical sets of responses occur. It's not hard to understand.

Replace a dice with a list of numbers. Take all your quantum events that affect all your snooker balls and make them the same time after time. Does the same thing happen? Yes.

What is so hard to *********** understand?

[Belz...]

Yes (http://physics.bgu.ac.il/~stotland/ARCHIVE/qcc_JPA.pdf)

Uh-huh. The words "random" and "fluctuation" don't appear in that text. Maybe you could cite the relevant passage...

[jimbob]

That's a Red Herring.

It doesn't matter. The billard balls can only respond to the unfolding situation. That doesn't make their response random. I fail to see why you can't make this distinction.

The response to an event is determined. The occurrence of the event is not. However as the response is determined under indentical sets of events indentical sets of responses occur. It's not hard to understand.

Replace a dice with a list of numbers. Take all your quantum events that affect all your snooker balls and make them the same time after time. Does the same thing happen? Yes.

What is so hard to *********** understand?

Why should you:

Replace a dice with a list of numbers. Take all your quantum events that affect all your snooker balls and make them the same time after time. Does the same thing happen? Yes.

The quantum events are not predetermined, they are random. They significantly affect the outcome, making the motion after about 12 collisions random, even in a perfect system, if it obeys the laws of physics. Why is it so wrong to describe the motion as random?

I can also ***** insert rows of ***** asterisks if I want to, but it ** make my *********** *** *** point any better.

[sol invictus]

However as the response is determined under indentical sets of events indentical sets of responses occur.

cyborg, I think jimbob's point is that in the Copenhagen interpretation of QM the statement I quoted above is just not correct. Identical circumstances do not lead to identical responses.

The only thing which is determined by the theory are probabilities, and furthermore it can be demonstrated that the probabilistic nature is not due to our ignorance - it is an intrinsic part of the theory. So according to that, the world is truly random at a microscopic level.

[jimbob]

Yes Sol, that is my point.

[cyborg]

Why should you:

Because I can even if reality can't.

The quantum events are not predetermined, they are random.

Which is irrelevant.

Identical circumstances do not lead to identical responses.

An event is not a circumstance. An event is what arises from circumstances.

Once the event has occurred how it occured it irrelevant to its effects. I do not understand why you cannot understand this.

[sol invictus]

An event is not a circumstance. An event is what arises from circumstances.

Once the event has occurred how it occured it irrelevant to its effects. I do not understand why you cannot understand this.

cyborg, read literally you're saying something totally empty - "if the events are the same, the events are the same". I think jimbob was trying to give you the benefit of the doubt and assume your statement wasn't tautological.

The issue at stake here is whether, given identical initial conditions, the outcome is the same. The answer is no - in standard interpretations of QM, at least. However this is indeed a red herring, since it is physically impossible to ever know whether the initial conditions are identical, and even in classical physics chaos means the uncertainties will grow exponentially, rendering some outcomes totally unpredictable even in principle.

[jimbob]

In this very simple system, you can set up the initial inputs, however there are randomly generated "internal" inputs, which make the outcome random when you look far enough into the future.

[cyborg]

The issue at stake here is whether, given identical initial conditions, the outcome is the same.

No, it really isn't.

The issue is that irrespective of the physicality of the situation it is always possible to create a deterministic model.

Recall, if you will, that this discussion is about the Theory of Evolution and describing it. I proposed that the basic relationships were that selection is deterministic with respect to form and mutation is non-deterministic with respect to the encoding of that form. The whole argument over randomness has been about the idea that natural selection is not deterministic. The basic reason for this that has been given is the argument outlined above:

"If you rewind the universe and press play you might not get the same thing."

My point is simply that:

It doesn't matter to the Theory of Evolution one jot.

Natural selection is simply a response to whatever the current situation is. It is not relevant the history of how a form came to exist - it only matters how it responds in the here and now. It matters not a jot if a mass extinction by an asteroid is the result of an atom decaying at an inconvenient time or the result of an alien insect species hurling it across the cosmos - it's still going to have the same effect and whatever forms happen to exist at the time will still have to respond to it and it is still only those who survive who matter.

If it sounds like a tautology then so be it but if the QM argument is solid then I fail to see why it should be possible for me to give the label "deterministic" to any phenomena in this reality.

[mijopaalmc]

Uh-huh. The words "random" and "fluctuation" don't appear in that text. Maybe you could cite the relevant passage...

They don't need to. The article explains quite well how the moments of a quantum mechanical distribution converge to the moments of a classical distribution.

[jimbob]

Cyborg, how is your approach remotely useful?

It misrepresents how evolution works.

Of course you can creatte fundamentally incorrect models that explain evolutionary history (they are called stories and are popular on bad nature "documentaries"), just as pre-Copernican (http://www.highdown.reading.sch.uk/highdown/pupil/time/calendars/patrick.html) models described the movement of the planets. It desn't make it right, or any more useful than a simpler, accurate description.

[jimbob]

Cyborg, are you claiming that random influences do not affect natural selection?

Back to the discussion about the cod fry...

A cod might produce a million fry, the population of cod is either stable or falling, so on average fewer than one fry per parent reproduces.

I say that any cod that do reprouce are obviously adapted enough, but that they were also lucky, whilst (I think) you claim that they are "fit" and those that fail to reproduce are by definition "unfit".

Again, this doesn't help with understanding, as you have to produce quite eccentric analyses of biology to fit your views. And I can't see how this allows you to accept, let alone quantify selective advantages, which many evolutionary biologists use and discuss (Dawkins included).

[Earthborn]

How about "directionless"? I think someone suggested that substitute, at some point.I don't remember anyone suggesting that (maybe in another thread) but I did write that we can call evolution "random" if we understand "random" as "without definite aim or direction". It was something that articulett disagreed with, because supposedly evolution does have an aim and direction. I don't agree that it does, so "directionless" is fine for me.

[mijopaalmc]

I don't remember anyone suggesting that (maybe in another thread) but I did write that we can call evolution "random" if we understand "random" as "without definite aim or direction". It was something that articulett disagreed with, because supposedly evolution does have an aim and direction. I don't agree that it does, so "directionless" is fine for me.

Perhaps you are referring to this exchange with articulett:

Earth born-- there's an aim... pass on your genes... those who don't, don't get to be a part of evolution... bummer. The genes that are best at getting themselves passed on drive evolution and make the process far from "random"...
repeat after me: random components do not a random process make.

ETA-- great Tai Chi' is here... you know you have a winner of a definition and explanation when the omnipresent Tai Chi' weighs in.

If your goal is to sound like Tai Chi and Behe-- just keep insisting that evolution is random and that somehow to someone you make more sense than Dawkins and all those who teach the subject to actual other people.

Natural selection is the "derandomizer"-- the mechanism that gives the appearance of design and the look that things somehow "knew" what features to evolve.

Earth born-- there's an aim... pass on your genes...Is that an aim, or is it just a result? And if it is an aim, whose aim is it? Is it God's aim? Is the aim of the organism carrying the genes who does not even know what genes are? Is it the aim of the genes, that don't have the mechanism to have 'aims' at all?

By introducing an 'aim' you are making a teleological argument instead of a cause and effect argument, which is generally frowned upon in the natural sciences. But who knows, maybe stones do fall back to Earth because they tend to move towards their natural place...

those who don't, don't get to be a part of evolution... bummer.Untrue. They are part of evolution, they just don't pass on their genes. But they do shape the environment in which others do pass on genes.

The genes that are best at getting themselves passed on drive evolution and make the process far from "random"...Which genes are best at getting themselves pass on depends on the environment, which is constantly changing.

repeat after me: random components do not a random process make.What if all components are subject to random changes?

That doesn't make the process random. If you aim to sound clear then use the words of those who convey the concept to others. If you aim to sound like T'ai-- refer to evolution as random. Processes are "steps in a procedure" one built upon the other... randomness is not related to past or future... Theoretically all things made of matter have random electron spins in their atoms... but who declares every thing random? And why would they?

Aim or direction applies to things without consciousness-- like wind or shooting starts or galaxies...it doesn't need to be conscious... it's just that physical laws make it so. Water and cold weather make lattices that form ice. It's a process. No one would call it random.

The same with evolution. Genes don't choose to get passed on... but those that do manage to do so drive evolution... the organism copying the DNA dies... but the information lives on to be copied again and possibly pick up a beneficial mutation in the process. It isn't random. No one who wants to convey what evolution actually is or help anyone else understand it, wouldn't describe it that way. It's a useless definition.

As Sol said, it's like picking up an apple and saying "this is something"... it's true... but uninformative. It's less useful than saying "evolution is a 4 syllable word"-- because while also being true... that doesn't have nearly the power to mislead or to be interpreted as "scientists think this all came about by random chance." Mijo's blather does. If your goal is to discuss evolution with Mijo, T'ai and Behe-- then by all means... you are doing a fabulous job. And an apple truly is something. And poker IS random per Mijo's definition.

Just don't expect anyone intelligent to think you actually understand the process or could correctly teach it to anyone else. You can't. You couldn't anymore than the person calling an apple a "something" could teach about apples. For the same reasons. It's equally uninformative and misleading. You end up wondering the motives of the person doing the describing -- if not their mental capacity. Really.

You can argue all you want and ask all the questions that you have... but that's the bottom line.

[articulett]

I don't remember anyone suggesting that (maybe in another thread) but I did write that we can call evolution "random" if we understand "random" as "without definite aim or direction". It was something that articulett disagreed with, because supposedly evolution does have an aim and direction. I don't agree that it does, so "directionless" is fine for me.

Really, you don't need to reinterpret my words... I feel like I say them just fine, and you interpret them wrong. Moreover, I think the people you are responding to interpret me just fine, and don't need your translations.

The "aim" of a gene is to get the most copies of itself in the environment... the genes that make the most reproductively successful organisms, multiply exponentially. In that way, the direction is towards more and more refined and honed genomes for a given environment over time. It's not a "plan" or "direction" as humans think of it... but it is a direction... just as orbital paths are directions...

Please don't try and tell others what I am saying. I consider you too ignorant to understand what I am saying much less to rephrase it and toss it off to others. I teach evolution. I understand those who teach it. I pass board exams on the subject. I read and understand peer reviewed articles on the subject. I understand why it's misleading and uninformative to call evolution random. I think those who do always have some bizarre reason for doing so that they never quite say. There are tons of great ways to describe evolution... why anyone would insist on calling it "random" despite the experts finding that incorrect is beyond me. But not really. I think I do know the reason. I suspect it's the same reason that Behe has. Gee, why would Behe (and T'ai) not listen to the experts on the subject or even Darwin when describing evolution? Why would they give an explanation that makes the main idea-- "natural selection" incoherent?? Hmmmmm

Does anyone think the self appointed experts are conveying evolution... particularly natural selection well? Does any expert on the topic sound so muddled and vague and obfuscating?

When you claim I said something I did not say or have motives I do not have that is "fighting a straw man" to avoid the fact that your argument fails.

A popular and useful definition of evolution that doesn't confuse like using "random" is:

Change in allele frequencies over time due to (or as determined by)natural selection.

[Walter Wayne]

Change in allele frequencies over time due to (or as determined by)natural selection.
It ain't evolution as we know it without mutation. Genetic drift is also part of evolution, but usually considered seperate from natural selection.

Walt

[Earthborn]

I consider you too ignorant to understand what I am saying much less to rephrase it and toss it off to others. I teach evolution. I understand those who teach it.You also have claimed that your way of describing it causes the least amount of misunderstanding among laypeople with no prior understanding of evolutionary theory... and yet you manage to be misunderstood and misinterpreted quite frequently. Could it be that you don't understand those you are teaching?

I understand why it's misleading and uninformative to call evolution random.I think everyone in this thread understands why calling evolution random can be misleading. It is just that some of us are saying that there is nothing special about the word "random" and that other terms can be just as misleading, which means that the word shouldn't be taboo just because it is misleading.

It is already pointed out to you that the use of the word "theory" can be misleading to laypeople. That's no reason to not use it.

Dawkins, in a quote above calls the theory of evolution "Darwinism" -- a term more often favoured by creationists than evolutionists -- which can also be very misleading it makes it appear all evolutionary theory comes from Darwin and is an -ism, like Marxism, capitalism or Islamism: a political philosophy. Yet I haven't heard you protesting that term; probably because you consider Dawkins too much of an authority to question his choices of words.

The "aim" of a gene is to get the most copies of itself in the environment... the genes that make the most reproductively successful organisms, multiply exponentially. In that way, the direction is towards more and more refined and honed genomes for a given environment over time. It's not a "plan" or "direction" as humans think of it... but it is a direction... just as orbital paths are directions...Calling it a "direction" is one thing, but using the word "aim" is very misleading and I think quite simply wrong.

I think those who do always have some bizarre reason for doing so that they never quite say.Try not to appear paranoid.

Why would they give an explanation that makes the main idea-- "natural selection" incoherent?? HmmmmmIt doesn't make natural selection incoherent. It shows what natural selection's options come from and what its criteria are.

Does anyone think the self appointed experts are conveying evolution... particularly natural selection well?Yes.

Does any expert on the topic sound so muddled and vague and obfuscating?I think you do.

Change in allele frequencies over time due to (or as determined by)natural selection.That is certainly a fine definition, for a narrow aspect of evolution. I disagree that it won't cause any confusion among laypeople with no prior understanding of evolutionary theory; how many of those understand what you mean with "allele frequencies" or "natural selection" ?

[cyborg]

Cyborg, are you claiming that random influences do not affect natural selection?

No. This isn't anything to do with what I'm saying at all.

I say that any cod that do reprouce are obviously adapted enough, but that they were also lucky, whilst (I think) you claim that they are "fit" and those that fail to reproduce are by definition "unfit".

No.

My point is whilst you can describe one cod and lucky and another as not you could also describe it as "this cod was here, which is where a predator was too - bad for the cod, good for the predator".

Saying it is simply "bad luck" is missing half the story.

[jimbob]

And saying that chance wasn't involved, also misses a significant part of the story, especially as the odds of an individual cod fry reproducing are of the order of 500,000:1 against. The fry could have traits that make it a thousand times more likely to reproduce, and it would still only have about a 0.2% chance of reproducing. If it did breed, and half its fry also had these traits, then you would expect about 500 offspring to reproduce, and the trait would spread.

Of course, in reality, beneficial mutations are only likely to give a few percent advantage. This is enough for evolution to work, but whether an individual trait spreads form its original parent has to be largely influenced by chance.

[cyborg]

And saying that chance wasn't involved, also misses a significant part of the story, especially as the odds of an individual cod fry reproducing are of the order of 500,000:1 against.

Uh no. Chance is just a way of describing your ignorance over which cod fry will survive but expressing your knowledge about how many are likely to be killed.

If all the predators were, for example, devastated by some disease your chance reproduction figures would become quite meaningless because they are not based on some fundamental property of the cod nor of the universe but on the avergage properties of the environment the cod find themselves in.

[jimbob]

And saying that chance wasn't involved, also misses a significant part of the story, especially as the odds of an individual cod fry reproducing are of the order of 500,000:1 against.

Uh no. Chance is just a way of describing your ignorance over which cod fry will survive but expressing your knowledge about how many are likely to be killed.

If all the predators were, for example, devastated by some disease your chance reproduction figures would become quite meaningless because they are not based on some fundamental property of the cod nor of the universe but on the avergage properties of the environment the cod find themselves in.

Uh no. Chance is just a way of describing your ignorance over which cod fry will survive but expressing your knowledge about how many are likely to be killed.
It is not just ignorance, but because of the influence of random events. The future history of an individual cod fry hasn't been determined at its hatching, because it will be affected by future random events:



An event is not a circumstance. An event is what arises from circumstances.

Once the event has occurred how it occured it irrelevant to its effects. I do not understand why you cannot understand this.

cyborg, read literally you're saying something totally empty - "if the events are the same, the events are the same". I think jimbob was trying to give you the benefit of the doubt and assume your statement wasn't tautological.

The issue at stake here is whether, given identical initial conditions, the outcome is the same. The answer is no - in standard interpretations of QM, at least. However this is indeed a red herring, since it is physically impossible to ever know whether the initial conditions are identical, and even in classical physics chaos means the uncertainties will grow exponentially, rendering some outcomes totally unpredictable even in principle.

ETA: If you were psychic, then that would be a different case.

[cyborg]

It is not just ignorance, but because of the influence of random events. The future history of an individual cod fry hasn't been determined at its hatching, because it will be affected by future random events:

So, to reiterate my previous statement:

if the QM argument is solid then I fail to see why it should be possible for me to give the label "deterministic" to any phenomena in this reality.

If your argument is "evolution is random because the cod fry's survival is at the whim of quantum mechanics," that is.

Which I find slightly preposterious - for some mad reason I kinda think it might be more helpful to consider the qualities of the environment such as the water, the existence of predators the raw materials availble for the biology of the fish and so forth. Not how any particular electron is going to behave.

ETA: Perhaps you'd like to demonstrate the relationship of the survival ratio of cod fry to an aspect of quantum determinance to bolster your case for its relevance?

[jimbob]

Did you see the comment about the difference between "weather" and "climate"?

Organisms will evolve in response to the climate, but individual selection events would be influenced by weather

[jimbob]

I'll ask this again:

Cyborg, how is your approach remotely useful?

It misrepresents how evolution works.

Of course you can creatte fundamentally incorrect models that explain evolutionary history (they are called stories and are popular on bad nature "documentaries"), just as pre-Copernican (http://www.highdown.reading.sch.uk/highdown/pupil/time/calendars/patrick.html) models described the movement of the planets. It desn't make it right, or any more useful than a simpler, accurate description.

[sol invictus]

If it sounds like a tautology then so be it but if the QM argument is solid then I fail to see why it should be possible for me to give the label "deterministic" to any phenomena in this reality.

But that is correct, of course. Classical determinism went out the window completely at the beginning of the 20th century.

Near the end of the 20th century, with the discovery of chaos, our understanding underwent another shift. The correct point of view now - in my opinion, at least - is that classical determinism is never a meaningful concept when applied to real systems, even if you ignore quantum mechanics.

Determinism is possible only in extremely simple and totally unrealistic mathematical models, like the two-body problem in Newtonian gravity.

[cyborg]

So what, exactly, has this argument got to do with evolution - at all?

Not a damn thing apparently - which makes any and all arguments that have been posited with respect to biology fallacious.

[articulett]

So what, exactly, has this argument got to do with evolution - at all?

Not a damn thing apparently - which makes any and all arguments that have been posited with respect to biology fallacious.

As well as utterly worthless and tangential to the OP.

[mijopaalmc]

So what, exactly, has this argument got to do with evolution - at all?

Not a damn thing apparently - which makes any and all arguments that have been posited with respect to biology fallacious.

Possibly that you made this statement:

The issue is that irrespective of the physicality of the situation it is always possible to create a deterministic model.

Deterministic models are not always reliable in terms of predictability, which is incredibly important when you are trying to make statements about physical systems.

[jimbob]

Back to the OP.

Mutation: Random and haphazard.

Natural slection: Probabilistic (due to chaotic systems) but not haphazard. (The "game" is played with loaded dice).

Evolutionary Direction: Stable for long periods of time, but affected by random events. Probabaly chaotic.

[articulett]

Whatever Jim-Bob... that's the mealy mouthed way you always have been promoting... no one's biting because it doesn't really describe natural selection... As I mentioned before, we don't tell people in genetic counseling that their chance of having a child with a certain disorder is probabilistic... because that doesn't convey information. We tell them what the probabilities are. And those probabilities are DETERMINED by multiple factors. It's as garbled as saying Poker is a game where the cards are dealt randomly, but the game is played probabilistically. No person who actually wanted to convey information to anyone would actually say that... though someone needing to define evolution as "random" might.

If you want to be taking seriously by those who understand and convey the topic to others, you might try communicating in the ways such experts do. If you are just trying to convince yourself that scientists somewhere think evolution is "random" (because it's probabilistic or whatever) then continue to argue this inane mealy mouthed definition that nobody but you (and maybe T'ai, Behe, and Mijo) are using. Try to convey what natural selection is with that garbled definition.

When you are explaining a model or a concept, it's important to be clear, don't you think?
It's not like you are wrong... it's just that you aren't really convey information in your muddledness and yet you are so sure you are. Why is it that you imagine you have expertise on this subject? Does anyone with expertise think you are making sense?

[cyborg]

Natural slection: Probabilistic (due to chaotic systems) but not haphazard. (The "game" is played with loaded dice).

Oh, so QM has got **** all to do with determining the survival ratio of cod fry has it now?

[jimbob]

Whatever Jim-Bob... that's the mealy mouthed way you always have been promoting... no one's biting because it doesn't really describe natural selection... As I mentioned before, we don't tell people in genetic counseling that their chance of having a child with a certain disorder is probabilistic... because that doesn't convey information. We tell them what the probabilities are. And those probabilities are DETERMINED by multiple factors. It's as garbled as saying Poker is a game where the cards are dealt randomly, but the game is played probabilistically. No person who actually wanted to convey information to anyone would actually say that... though someone needing to define evolution as "random" might.

As I mentioned before, we don't tell people in genetic counseling that their chance of having a child with a certain disorder is probabilistic... because that doesn't convey information.

Nor do I when describing natural selection.

I have even described it how I would convey information when discussing genetic disorders

within the spoiler for brevity:

So then it's random as to whether two carriers of sickle trait have a child with sickle cell anemia? And it's random as to whether you get an A on a test? And it's random as to whether seat belts save lives? -- and what passes through a sieve is random. If you have a royal flush, your chances of winning are random. That's just a piss-poor non-descriptive vague use of random. If you want to convey how order comes from randomness you better quit describing random as "any model that requires probability"... or provide at least one peer reviewed paper that describes random in that way.

So then it's random as to whether two carriers of sickle trait have a child with sickle cell anemia?

Essentially, yes. As you know the odds are 50% per child (assuming no screening), so the odds depend on the number of children.

If the family has 1 child the odds are 50% (1/2)
If the family has 2 children the odds are 25% (1/2)^2
If the family has 3 children the odds are 12.5% (1/2)^3

That none of the children will have sickle cell anaemia.
and so on.

How would you describe the chances of having a child with sickel cell anaemia


If only one parent was a carrier, then the odds are vanishingly that any child would have sickle cell anaemia. (The advantages of sexual reproduction and avoidance of inbreeding).

And a later correction to my sums:

I have just realised that I had stated the odds for all children being carriers, but without the full sickle cell trait.

The odds of two carriers having all their children without full sickle cell are

3/4 for 1 child
9/16 for two
27/64 for three

Anyway, articulett, would you tell the parents that any child they had would have a 25% chance of having sickle cell? Then discuss the implications of this.





Have you read my posts where I describe the probabilities and describe the probability distribution? For a stable population it could be described by a poisson distribution with a lambda of 1 reproducing offspring per parent. This tells you the probabilities; it also tells you the probabilities if a trait confered an x% reproductive advantage or disadvantage.


If you want to be taking seriously by those who understand and convey the topic to others, you might try communicating in the ways such experts do. If you are just trying to convince yourself that scientists somewhere think evolution is "random" (because it's probabilistic or whatever) then continue to argue this inane mealy mouthed definition that nobody but you (and maybe T'ai, Behe, and Mijo) are using. Try to convey what natural selection is with that garbled definition.

When you are explaining a model or a concept, it's important to be clear, don't you think?
It's not like you are wrong... it's just that you aren't really convey information in your muddledness and yet you are so sure you are. Why is it that you imagine you have expertise on this subject? Does anyone with expertise think you are making sense?


Why am I not conveying information? Here is my "insincere" question again (it isn't insincere, so would you please tell me

1) Why the questions are wrong?
2) Why it is wrong to approach them probabilistically?
3) How to answer such a question without using a probabilistic approach?
4) How is this unclear, garbled or muddled for a numerate audience?

I prefer talking about traits, because if the selection pressures are for smaller individuals (e.g. on an island with a reduced population) individuals with this trait have the advantage, and it it doesn't matter what gene is different, as long as the end result is a smaller organism.

In this case about half the population of offspring would have a smaller mature size than their parents, and thus the selective advantages work for a larger number than ifo one is talking about a single mutation.

In the case of a single advantageous mutation arising initially in one individual; the best (only) way of assessing how likely this mutation is to spread through the population is to perform a probabilistic analysis. It would be more advanced than my simple versions, but it needen't be by much.

Articulett,

In a stable population, a single advantageous mutation provides a 10% selective advantage, and arises in a single (asexually reproducing) organism.

The average brood size for this type of organism is 10.

1) At the birth of this organism, what is the probability of the mutation spreading through the population?

2) The organism makes it through to breed,

a) What is the probability of the mutation spreading now?

b) What is the probaility of the mutation remaining for 5 generations?

3) The mutation is now in 1% of a large popluation, now what is likely to happen?

I think these are usefull types of questions, and ones that can be only answered probabilistically, how would you answer such questions?

[jimbob]

Oh, so QM has got **** all to do with determining the survival ratio of cod fry has it now?

I thought you were more numerate than that.

I contend that an organism's survival is determined by many interacting chaotic systems, the weather being the first one to spring to mind.

The fundamental properties of chaotic systems mean that over large enough timescales they are (to simplify) random. The fundamental reason is because of nonlinear magnification of quantum uncertainties, however even without QM, the system would still be unpredictible. With QM it is also random. Far enough into the future, the weather is random, but we can still talk about the climate.

[cyborg]

I thought you were more numerate than that.

I've seen a distinct lack of numbers here but a lot of extrapolation well beyond that which is justifiable.

[jimbob]

I've seen a distinct lack of numbers here but a lot of extrapolation well beyond that which is justifiable.

This seems to be pretty well accepted by the vast majority of physicists:

It is a digression dogression, but chaotic systems are hypersentistive tio initial conditions so that a classical treatment requires accuracy that doesnt actually exist.

Here (http://physicaplus.org.il/articles2/barrow_eng.html) is a discussion about a very simple system (from the Israel physical society)

You can apply this rule to snooker balls as well as molecules. One knows from bitter experience that snooker or pool exhibits sensitive dependence on initial conditions: a slight miscue of the cue-ball produces a big miss! If the balls are bouncing around a frictionless snooker table in a perfect vacuum (otherwise they will just stop moving after one or two collisions) then we might typically have d=1 metre and r=3 cm, so our map is qn+1 = 3qn. The growth in recoil angle uncertainty in the trajectory of a ball as it bounces off other balls is therefore pretty dramatic. In fact, if you hit the ball as accurately as Heisenberg's quantum Uncertainty Principle allows any physical process to be determined by observation, then only about 12 collisions are needed to amplify this uncertainty up to more than 90 degrees!

Twenty-four collisions ahead, and there are twelve sets of collisons where the accuracy required would be beyind the uncertainty principle.

Why is it wrong to describe the behaviour of the snooker ball that far ahead as random? Not just unpredictible, but random.

You would be wrong to describe the behaviour three collisions ahead as random, but twenty four, or thirteen collisions ahead?

This is a simple system but it does involve classical mechanics in a chaotic system, and thus for far-enough ahead is random.

Weather systems, which affect individual organisms is similarly a chaotic system, so I cant see why this behaviour far enough ahead isn't truely random.

Indeed I can't see why any choatic system, far enough ahead, isn't random.

It was a simple deterministic system, which after a few (12) iterations became "random".

Biology contains many more complex chaotic systems interacting, and it is a fundamental property of chaotic systems that after a certain time they require accuracy at the quantum level, which is random.

[cyborg]

Biology contains many more complex chaotic systems interacting, and it is a fundamental property of chaotic systems that after a certain time they require accuracy at the quantum level, which is random.

So like any true Physicist your imposition of irrelevant details onto another scientific theory is simply that "it relies on physics".

So biology is a Red Herring.

[articulett]

Last I checked billiard balls on hypothetical pool tables aren't passing their DNA into the future based on how well they meet the rigors of the present...

genomes get more refined and honed and "complex" over time... a little different then what happens to snicker balls when struck by a cue, eh?

Natural Selection Jim. It is the de-randomizer... it makes evolution very unlike your billiard ball example. It allows for iteration of information over time--the opposite of increasing randomness... actually "increasing" refinement and complexity and reproductive efficacy.

How does your example compare to evolution... particularly the OP? To whom would this be useful or explanatory? In what way? How does this relate to natural selection... remember "natural selection" is like artificial selection... but over a much longer period of time with the environment "selecting" the winners--not human preference.

[jimbob]

But articulett, real ecosystems are messy. Natural selection is not 100% effective, although it is pretty close when it comes to removing even slight disadvantages. It is messy because of the chaotic interactions, and this leads to an element of randomness in natural selection.

Cyborg might argue that natural selection is deterministic and that you could hypothetically show this if your model had enough information, but chaotic systems don't work like that.

You can see how this affects the mechanism of natural selection with some simple observations and reasoning:

in the below post (link here) (http://forums.randi.org/showthread.php?postid=3571488#post3571488) I have been assuming that most of the offspring resemble their parents so that on average chance mutations are equally likely to improve the reproductive chances of any owlet, as reduce them.

In other words, natural selction is very effective at culling disadvantageous traits, but pretty inneffective at preserving any individual advantageous ones.

Do you agree that the following example is situation where the probabilistic nature of natural selection is usefull in highlighting more about the implications than pretending that chance has no part in natural selection?

I think a valid analogy might be between weather and climate. The individual slection event might be "random" but the efffect over a large enough population means that some beneficial traits will propagate.

Doing the sums, I would conclude that most "beneficial" traits that arise probably don't survive more than one generation.

This is because the odds are against any individual organism reproducing, for virtually any species (possibly except our own currently). For example, the Barn Owl population is roughly stable, but it tends to have a clutch sizes of about 3-7 and sometimes breed twice a year, and live for 1-5 years in the wild (25 years in captivity). Of the total brood size over the lifetime of the pair, on average only two offspring will breed if the population is stable.

Say this equates to 5 clutches, of 4 birds. Then there is 90% chance of any individual not breeding, and a 10% chance of it breeding. To get an evens chance of a particular trait making it past the first individual, it would need to confer a 500% advantage compared to its peers...

However we are dealing with big numbers, and some (enough) advantageous traits will survive and get passed on...

Disadvantageous traits are almost certain to vanish very quickly. In the barn owl example, a neutral trait already has a 90% chance of not getting passed on.

Malthusian reasoning also leads us to the conclusion that similar situations will occur most of the time in nature.

[cyborg]

Yawn

You're talking as if you're providing any new information. You're just not getting what is being said and I'm getting tired of explaining myself.

[Belz...]

They don't need to. The article explains quite well how the moments of a quantum mechanical distribution converge to the moments of a classical distribution.

So... let me get this straight. You say:

Quantum randomness has an orderly classical (or semiclassical) limit.

Whatever that means. So I ask "does it ?", to which you answer with a link that doesn't even mention randomness, and now you say it still supports your point ?

Would you mind citing the relevant passage, as I've already asked you ? Or will you just keep claiming that it says what you want it to say ?

[Belz...]

Determinism is possible only in extremely simple and totally unrealistic mathematical models, like the two-body problem in Newtonian gravity.

And yet everything averages out so that our predictions work remarkably well, every time. Sounds deterministic to me, no matter how random the underlying physics are.

[sol invictus]

And yet everything averages out so that our predictions work remarkably well, every time. Sounds deterministic to me, no matter how random the underlying physics are.

Every time? Can you given an example of a prediction like that?

Certainly there are things we can predict with high accuracy, but the predictions are always probabilistic.

There may be a semantic issue here - the word "deterministic" has a very specific technical meaning which is not compatible with randomness in the underlying physics.

[Dancing David]

It ain't evolution as we know it without mutation. Genetic drift is also part of evolution, but usually considered seperate from natural selection.

Walt

Thats very silly, why are artic foxes white? Any difference in genetics which influences reproduction is subject to natural selection.

Where did your notion come from?

[Dancing David]

And saying that chance wasn't involved, also misses a significant part of the story, especially as the odds of an individual cod fry reproducing are of the order of 500,000:1 against. The fry could have traits that make it a thousand times more likely to reproduce, and it would still only have about a 0.2% chance of reproducing. If it did breed, and half its fry also had these traits, then you would expect about 500 offspring to reproduce, and the trait would spread.

Of course, in reality, beneficial mutations are only likely to give a few percent advantage. This is enough for evolution to work, but whether an individual trait spreads form its original parent has to be largely influenced by chance.


And natural selection doesn't care. It is not about the individual, although they are the ones who reproduce or not. A species is composed of individuals, the mean traits of a species are not significant for the individual.

yes fish economics are a high output low probability , even worse for bug economics.

Natural selection doesn't care about the chances of an individual, that is strange deterministic thinking.

Natural slection happen every time an organism reproduces.

[Dancing David]

Back to the OP.

Mutation: Random and haphazard.

Natural slection: Probabilistic (due to chaotic systems) but not haphazard. (The "game" is played with loaded dice).

Evolutionary Direction: Stable for long periods of time, but affected by random events. Probabaly chaotic.


Just like Mijo and Wayne, you are hung up on mutation, gosh , it is NOT the only means of genetic variability. It is not the only factor in variability that effects natural selection.

Why are you three obsessed with it?

Why are artic foxes white?

[Walter Wayne]

Thats very silly, why are artic foxes white? Any difference in genetics which influences reproduction is subject to natural selection.

Where did your notion come from?
What is your issue with my quote. Is mutation not a component of our current understanding of evolution? Does it not create the new "information" that natural selection acts on.

Just like Mijo and Wayne, you [jimbob] are hung up on mutation, gosh , it is NOT the only means of genetic variability. It is not the only factor in variability that effects natural selection.

Why are you three obsessed with it?

Why are artic foxes white?
Hung up on mutation? That's hillarious.

Articulett left it out of her "useful definition" of evolution all together, and claimed natural selection was responsible for iteration of information (not heredity) and "increasing" complexity (not mutation). I'm not hung up on it, rather I am giving it its proper place. How anyone can claim to have an expertise on the subject of evolution, but not realize the roles of the different components of it is beyond me.

Both Jimbob and I are also arguing that it is the properties of natural selection, that make the process random at larger scales. I have even argued elsewhere, that even if mutation was determistic, evolution would still be random except in the most technical sense of it.

Walt

[sol invictus]

Articulett left it out of her "useful definition" of evolution all together, and claimed natural selection was responsible for iteration of information (not heredity) and "increasing" complexity (not mutation). I'm not hung up on it, rather I am giving it its proper place. How anyone can claim to have an expertise on the subject of evolution, but not realize the roles of the different components of it is beyond me.

I think her (?) point is that mutation is not necessary for evolution. Imagine starting with a population with some genetic variability present in the genome, but with no mutations possible. That population will evolve under natural selection, perhaps towards more complexity (for example if the more complex organisms present are more fit, or through simple sexual reproduction).

Obviously mutation was a crucial part of the evolution of life on earth up to this moment, but it is not necessary for evolution per se, and it is not responsible for many of the examples of evolution we see occurring on shorter time scales.

[Belz...]

Every time? Can you given an example of a prediction like that?

Certainly there are things we can predict with high accuracy, but the predictions are always probabilistic.

There may be a semantic issue here - the word "deterministic" has a very specific technical meaning which is not compatible with randomness in the underlying physics.

Well, for one we can send probes to pluto and they actually get there.


As I've learned from my time here, "random" and "deterministic" seem to be able to mean anything we want!


So, honey, pass the deterministic, please. No, the other one.

[sol invictus]

Well, for one we can send probes to pluto and they actually get there.

Always? You think if we sent 100 probes to Pluto, they'd all get there? Considering the that NASA has difficulty (http://mars.jpl.nasa.gov/msp98/news/mco990930.html) even converting metric to english, I doubt that very much.

As I've learned from my time here, "random" and "deterministic" seem to be able to mean anything we want!

Yes :).

But there really is a technical definition (http://en.wikipedia.org/wiki/Scientific_determinism) of determinism, and probabilistic systems don't meet it. Actually "random" is much harder to define - it's not really a technical term at all, contrary to what mijo likes to claim.

[Wowbagger]

Well, I suppose there can be technical definitions of the word "random" in different contexts. It's just that there are a lot of different contexts.

[sol invictus]

Well, I suppose there can be technical definitions of the word "random" in different contexts. It's just that there are a lot of different contexts.

I think it's just very hard to define precisely. I checked a standard textbook on probability theory and it didn't define it at all - in fact it essentially never used it (there were only two instances of the word, both informal).

You can define a random variable in a formal way, as here (http://en.wikipedia.org/wiki/Random_variable), but as we've seen that doesn't provide a useful definition of "random". And even mijo, after months (or years?) of harping on this, still didn't understand even that not-so-useful definition, as the exchange regarding the wave function a few pages back evidenced.

Actually it might be interesting to open a thread on randomness - it's really a very slippery concept - and that slipperiness might have something to do with the ridiculous length of this discussion.

[cyborg]

As I have proposed before algorithmic descriptions provide a much more tangeable notion of randomness.

In short this is:

Sequences for which the shortest algorithm (with input included) for producing them is the sequence itself are random.

[sol invictus]

As I have proposed before algorithmic descriptions provide a much more tangeable notion of randomness.

In short this is:

Sequences for which the shortest algorithm (with input included) for producing them is the sequence itself are random.

Well, that's a good approach, but you're not there yet. Any given finite sequence can be compressed at least a little. So you have to define this as some kind of limit, for an infinite number of sequences or infinite length ones. That's where it gets subtle.

[cyborg]

Any given finite sequence can be compressed at least a little.

No it can't.

Simple counter-example for you - compress this sequence:

1

[Dancing David]

What is your issue with my quote. Is mutation not a component of our current understanding of evolution? Does it not create the new "information" that natural selection acts on.


Hung up on mutation? That's hillarious.

Articulett left it out of her "useful definition" of evolution all together, and claimed natural selection was responsible for iteration of information (not heredity) and "increasing" complexity (not mutation). I'm not hung up on it, rather I am giving it its proper place. How anyone can claim to have an expertise on the subject of evolution, but not realize the roles of the different components of it is beyond me.

Both Jimbob and I are also arguing that it is the properties of natural selection, that make the process random at larger scales. I have even argued elsewhere, that even if mutation was determistic, evolution would still be random except in the most technical sense of it.

Walt

You and the other two are hung up on mutation, it is NOT the only thing that natural selection acts upon.


It ain't evolution as we know it without mutation.

is your quote.

Do you really think that artic foxes are white because of a mutation? Do I really have brown eyes because of a mutation (both my parents have hazel eye).

there are variations in the genome that don't require mutation as the basis of vaiability. I can speel it out for you if you want, I will ask again:

How does mutation make artic foxes white?

Answer the question.

[Belz...]

Always? You think if we sent 100 probes to Pluto, they'd all get there? Considering the that NASA has difficulty (http://mars.jpl.nasa.gov/msp98/news/mco990930.html) even converting metric to english, I doubt that very much.

Yeah but all kidding aside, the probes that wouldn't get there wouldn't not because pluto skips an orbit, or anything, but because of a technical difficulty or unknown variable such as collision, etc.

[Wowbagger]

I think it's just very hard to define precisely. I checked a standard textbook on probability theory and it didn't define it at all - in fact it essentially never used it (there were only two instances of the word, both informal). I know that when Dawkins has used it, it meant something similar to "directionless" and/or "indifferent", but I wonder how he would define it more precisely. Hmmm...

Actually it might be interesting to open a thread on randomness - it's really a very slippery concept - and that slipperiness might have something to do with the ridiculous length of this discussion. Another one?! I suppose a more generic thread, on what randomness actually is (aside from its relevance to biology), might be useful.

If any long tirades about evolution crop up in it, we should be sure to point them back here.

[jimbob]

Yawn

You're talking as if you're providing any new information. You're just not getting what is being said and I'm getting tired of explaining myself.

Well you have never explained how your approach is useful in answering those sort of questions.

If you are saying that evolution doesn't need probabilistic selection to work, that might be arguable*, however I have been under the impression that we have been discussing how evolution works, within known biology. In this example, it works probabilistically, fitness and luck both play a part.

*It would still be wrong though for the following reasoning.

For darwinian evolution it is necessary and sufficient for there to be imperfect self-replication.

If there is, then in any finite system, there will eventually be a resource limitation, thus there will be competition amongst the replicators, which will lead to natural selection, even without any other form of natural selection.

The replicators will thus affect the selective landscape for the surrounding replicators. This type of feedback loop is charateristic of certain types of chaotic system.

If the evoutionary landscape is chaotic, then the evolutionary direction is chaotic. And if it is chaotic, it is wrong to say that it is completely nonrandom, as over long enough timescales, it is random.

The selection is also likely to be chaotic for the same reasons.

[cyborg]

For darwinian evolution it is necessary and sufficient for there to be imperfect self-replication.

Oh, here we go again.

If the evoutionary landscape is chaotic, then the evolutionary direction is chaotic. And if it is chaotic, it is wrong to say that it is completely nonrandom, as over long enough timescales, it is random.

You still haven't understood a singular thing I've said.

Come back to me when you understand what I mean by "algorithmic complexity" then we can discuss the notions of "chaos", "random" and "completly non-random" with some sort of formalism rather than, "well, we all know what that means".

[jimbob]

Yeah but all kidding aside, the probes that wouldn't get there wouldn't not because pluto skips an orbit, or anything, but because of a technical difficulty or unknown variable such as collision, etc.

We are talking about long timescales here:

According to wiki, Pluto's orbit is unpredictible beyond about ten million years.

I'd imagine that chaotic NEOs are on a slightly shorter timeframe, having a higher orbital frequency, but even ten million years in the context of the 3.8 billion that life has been on Earth is sufficiently short for it to be considered random.

Again I'll reiterate, you can make predictions, but they need to be probabilistic if talking about suitably long timescales.

[mijopaalmc]

No it can't.

Simple counter-example for you - compress this sequence:

1

You obviously have no idea what "trivial case" means.

[cyborg]

You obviously have no idea what "trivial case" means.

I know what "any" means. "Trivially" he's wrong.

He's still wrong non-trivially:

http://www.faqs.org/faqs/compression-faq/part1/section-8.html

Here's the important bit:

Theorem:
No program can compress without loss *all* files of size >= N bits, for
any given integer N >= 0.

Proof:
Assume that the program can compress without loss all files of size >= N
bits. Compress with this program all the 2^N files which have exactly N
bits. All compressed files have at most N-1 bits, so there are at most
(2^N)-1 different compressed files [2^(N-1) files of size N-1, 2^(N-2) of
size N-2, and so on, down to 1 file of size 0]. So at least two different
input files must compress to the same output file. Hence the compression
program cannot be lossless.

[jimbob]

Are you talking about evolution as it works in nature, or some model of evolution?

[cyborg]

There is nothing but "some model of evolution". Nature doesn't go about thinking, "ah yes, this is how evolution works so this is what I must do."

[sol invictus]

No it can't.

Simple counter-example for you - compress this sequence:

1

That's easy to compress - beep means the sequence "0", no beep means "1". Since you gave "1", I send nothing.

If you don't want to count that, all you have to do is amend what I said to apply to all finite sequences of at least 2 bits.

I know what "any" means. "Trivially" he's wrong.

He's still wrong non-trivially:

http://www.faqs.org/faqs/compression-faq/part1/section-8.html

Here's the important bit:

No, you either didn't read or didn't understand what I wrote. What I said was that any finite sequence can always be compressed. What that says is that no one algorithm can compress all sequences of length N and larger. Those are totally different statements, and they are not in contradiction.

Now - what is your definition of a finite random sequence?

[jimbob]

No it can't.

Simple counter-example for you - compress this sequence:

1

That's easy to compress - no signal means the sequence "1", a signal means "0". Since you gave "1", I send no bits (no signal).

If you don't want to count that, all you have to do is amend what I said to apply to all finite sequences of at least 2 bits.

I know what "any" means. "Trivially" he's wrong.

He's still wrong non-trivially:

http://www.faqs.org/faqs/compression-faq/part1/section-8.html

Here's the important bit:

No, you either didn't read or didn't understand what I wrote. What I said was that any finite sequence can always be compressed. What that says is that no one algorithm can compress all sequences of length N and larger. Those are totally different statements, and they are not in contradiction.

Now - what is your definition of a finite random sequence?

Ooh,ooh, I have an example of a finite random sequence: it is described in this post:

That's a Red Herring.

It doesn't matter. The billard balls can only respond to the unfolding situation. That doesn't make their response random. I fail to see why you can't make this distinction.

The response to an event is determined. The occurrence of the event is not. However as the response is determined under indentical sets of events indentical sets of responses occur. It's not hard to understand.

Replace a dice with a list of numbers. Take all your quantum events that affect all your snooker balls and make them the same time after time. Does the same thing happen? Yes.

What is so hard to *********** understand?


Replace a dice with a list of numbers. Take all your quantum events that affect all your snooker balls and make them the same time after time. Does the same thing happen? Yes.

That would seem to be a finite random list. I'll bet there is no simpler algorithm that can generate these numbers every time, other than that list.

[sol invictus]

That would seem to be a finite random list. I'll bet there is no simpler algorithm that can generate these numbers every time, other than that list.

I'm not sure I understand your example. You want to make a list of numbers based on some presumably random process (like positions of snooker balls after 24 bounces)?

That's trivial to compress - whatever it is, just call it 1.

The point is, I don't think there's any way to tell if something is random (or even define the term) if you only have a finite number of instances of it. You need an infinite number, which we never have.

[Walter Wayne]

You and the other two are hung up on mutation, it is NOT the only thing that natural selection acts upon.I never said it was.

Do you really think that artic foxes are white because of a mutation? Do I really have brown eyes because of a mutation (both my parents have hazel eye)."Artic foxes are white because of mutation" does not follow my from my statement about the importance of mutation as a component of evolution. Evolution explains alot more than why your eye colour from last generation to this one.

By the way, if I recall hazel eyes are blend of the co-dominant brown and blue. Thus your eyes as compared to your parent is purely hereditary. But the blue gene your parents have is believed to be a recent mutation, so their hazel eyes are the result of mutation and selection. They can not be said to be caused by just mutation, ro just selection.

Link (http://www.dailymail.co.uk/pages/live/articles/technology/technology.html?in_page_id=1965&in_article_id=511473)
The team, whose research is published in the journal Human Genetics, identified a single mutation in a gene called OCA2, which arose by chance somewhere around the northwest coasts of the Black Sea in one single individual, about 8,000 years ago.
So your parents eyes were hazel because of mutation ... and selection, recombination, drift,....

Walt

[jimbob]

That would seem to be a finite random list. I'll bet there is no simpler algorithm that can generate these numbers every time, other than that list.

I'm not sure I understand your example. You want to make a list of numbers based on some presumably random process (like positions of snooker balls after 24 bounces)?

That's trivial to compress - whatever it is, just call it 1.

The point is, I don't think there's any way to tell if something is random (or even define the term) if you only have a finite number of instances of it. You need an infinite number, which we never have.

Sorry, I was being slightly snide. (In the context of the surrounding posts, the first few numbers wouldn't be random, but later ones would be).

My real question was aimed at Cyborg, which was:

Does he consider this to be a list of random numbers?

What about a table of numbers obtained by rolling a set of dice repeatedly?

I think he is saying that all random numbers consist of

"Sequences for which the shortest algorithm (with input included) for producing them is the sequence itself." so the sequence can't be compressed.

Wouldn't that make any perfectly compressed communication random?

I also can't see why it doesn't require something magical preventing lists of random numbers from containing patterns, 10% of random numbers will divide by 10, and 1% will divide by 100, if you turn the sequence into one long number. (which is what we are doing in typing)

I have another sequence which consists of three numbers:

2 4 6

I can't think of another way of defining those three numbers, and no more than those three, that is shorter, without some prior information (like calling it one).

[cyborg]

That's easy to compress - beep means the sequence "0", no beep means "1". Since you gave "1", I send nothing.

I thought you might take that out.

No, you either didn't read or didn't understand what I wrote. What I said was that any finite sequence can always be compressed.

No. You cannot compress a random sequence with any algorithm and gain any reduction in information required to express it.

For example if you were to say, "I can compress 10 by creating an algorithm that outputs 10 if the input is 1," then, per the definition I gave earlier which includes the size of the algorithm, the algorithm must, at the very least, contain the string "10" and hence be at least as large as the sequence it's trying to encode meaning you gain nothing by encoding it as the sequence "1", or even "".

Compression is not recursively applicable - your statement: "Any finite sequence can always be compressed," would allow for one to repeatidly apply compression - say reducing the sequence by 1 bit each time - until there are no bits in the sequence. This is clearly a nonsense. If you used a different algorithm at every stage every algorithm must be included in the count as to how much information was required - you can't magic up the data from nowhere.

This means:

That's trivial to compress - whatever it is, just call it 1.

Is a cheat that I've already covered.

So before you accuse me of not reading you properly I suggest you make sure you're not assuming what you think I'm saying.

Wouldn't that make any perfectly compressed communication random?

Absolutely - so should any decently compressed file.