Randomness in Evolution: Valid and Invalid Usage

[Wowbagger]

Here is a thread to discuss how the word "random" applies, or does not apply, to the Theory of Evolution, depending on how you define the word, and stuff like that.

I have started this thread, so that no others need to get derailed on this (often semantically and mathematically confusing) topic. (I hope it's not too late!)

Here is a summary of my current position, for starters:

The word "random" is often used, in different contexts, when describing evolution. But, it does not need to be used. And, its usage often contributes to confusion, which is why I like to avoid it, myself.

Although, I will admit there are both valid and invalid uses of the term.

Valid usage includes, but might not be limited to:

* Describing mutations where the word "indifferent" could be a substitute. For example, instead of saying "mutations are random to the life form's survival", you could say "mutations are unconsciously indifferent to the life form's survival". (This is more or less the context I have seen Richard Dawkins use.)

* Describing a model of evolution, where our knowledge is not perfect. Such usage implies that the Evolution is actually deterministic behind the scenes. But, information about its initial conditions are lost to time and thermodynamics; and the number of variables involved in the current conditions are too many for us to handle. Therefore, we resort to simplified models that utilize either stochastic algorithms and/or random variables. As the models improve, the less we rely on these things.

Invalid usage includes, but might not be limited to:

* "Random chance", "blind chance", "happy accident", etc. Any term that implies Evolution is all about complete and utter randomness. Evolution is an algorithm, and one that was practically inevitable to crop up somewhere in the Universe (likely more than one place). To imply evolution is random, in this manner, is to misconstrue its nature. In part, because it implies lack of predictive power.

* Appeals to quantum uncertainty. While quantum uncertainty might have some small impact on the course of evolution, it would be unfair to "out" Evolution as a theory of randomness because of this, simply because quantum uncertainty makes an impact on all of the other sciences, as well. Also, most quantum fluctuations are averaged out (or "smeared out") in large scales, anyway.

* Referring to Arthur Dent's daughter. She has nothing to do with this!

In any definition of the term, the more we study about life, the more precision we can make in our predictions, and the less randomness plays a role. If Evolution was supposed to be a theory about randomness, you would think the opposite trend would take place.

Your thoughts?

[Walter Wayne]

* Referring to Arthur Dent's daughter. She has nothing to do with this!

...

Your thoughts?
I'd like to point out that Arthur Dent's daughter, being responsible for the extinction of human kind and all other earth species, is by no means a bit player in evolution.

I will get to the rest of the post when I have more than just a lunch break to post, but thought that such an egregious error had to be correct as soon as possible.

Walt

[Belz...]

I've always thought that "random" either means we have not enough information to predict the outcome or that it implies acausal processes.

[Vorticity]

Sweet Jesus. Not again.

This thread will come to a bad end.

[shadron]

* Describing mutations where the word "indifferent" could be a substitute. For example, instead of saying "mutations are random to the life form's survival", you could say "mutations are unconsciously indifferent to the life form's survival". (This is more or less the context I have seen Richard Dawkins use.)

I'll cite http://genomebiology.com/2005/6/6/R50, which says:

Among three sources of evolutionary innovation in gene function - point mutations, gene duplications, and gene shuffling (recombination between dissimilar genes) - gene shuffling is the most potent one.

The first two are, perhaps, covered by the point above; their result is, indeed, indifferent to the survival of the individual sufferer. The third, being a naturally occurring random process, is not covered, but needs to be; it is the major "reason" for sexual reproduction being a valuable process to a genome. And it make cats interesting, as well.

[Taffer]

From the previous thread:

You seem to have missed the posts where cyborg has said that acausality is necessary to randomness:

If, as cyborg claims, acuasality is necessary to randomness, then randomness cannot be without acausality; therefore, one must have acausality to have randomness, acuasality defines randomness, and random means acausal.

Belz understood it. All truely random events are acausal. But for "random" to mean "acausal", all situations of acausality must be considered random. However, that does not follow from the premise "all random events are acausal".

You are trying to say:
If A then B
∴ If B then A
∴ A = B

Which is not a valid argument.

[Almo]

I would say that evolution as a process harnesses random events (mutations) as a means of generating variety.

[Wauthan]

I'd say that mutation is random within limits. If you mutate too much, or against selective pressure, you can't have kids. If you mutate too little, or get "locked inside" a specialized biological niche, you can't adapt to changes in the enviroment.

Mutation might be random but evolution follows rules. Squeeze mutation through evolution and you end up with sort-of-randomness.

[Belz...]

You are trying to say:
If A then B
∴ If B then A
∴ A = B

Which is not a valid argument.

It's amazing how many people make that mistake.

[mijopaalmc]

From the previous thread:



Belz understood it. All truely random events are acausal. But for "random" to mean "acausal", all situations of acausality must be considered random. However, that does not follow from the premise "all random events are acausal".

You are trying to say:
If A then B
∴ If B then A
∴ A = B

Which is not a valid argument.

You're still missing the point (why am I not surprised?:rolleyes:). At no point did either cyborg or I say that acausality was the only characteristic of randomness. However, as cyborg has said several time in the other thread acausality is a necessary condition for randomness. Since randomness simply would not exist without acausality, as acausality is a necessary condition for randomness in part defines randomness, acausality in part defines randomness, and therefore, random means in part acausal.

[Third Eye Open]

I think a better word for the things most people call 'random' would be 'chaotic'.

[Taffer]

You're still missing the point (why am I not surprised?:rolleyes:). At no point did either cyborg or I say that acausality was the only characteristic of randomness. However, as cyborg has said several time in the other thread acausality is a necessary condition for randomness. Since randomness simply would not exist without acausality, as acausality is a necessary condition for randomness in part defines randomness, acausality in part defines randomness, and therefore, random means in part acausal.

You're still missing the point (why am I not surprised?:rolleyes:). Something doesn't mean something else unless the are equivalent. Belz understood this. Unless you are now trying to say random only partly means acausal, in which case you would only be partly correct, wouldn't you?

This is pointless anyway. Let us grant you that "randomness" equates to "acausal". What does this get us? It means nothing to evolution by natural selection - the acausal element only creates variation, variation which could arise by any means at all and evolution would still occur.

What is your point with all this?

[mijopaalmc]

You're still missing the point (why am I not surprised?:rolleyes:). Something doesn't mean something else unless the are equivalent. Belz understood this. Unless you are now trying to say random only partly means acausal, in which case you would only be partly correct, wouldn't you?

I''m sorry, but are you saying that a necessary condition does not provide part of the meaning to its possessor?

This is pointless anyway. Let us grant you that "randomness" equates to "acausal". What does this get us? It means nothing to evolution by natural selection - the acausal element only creates variation, variation which could arise by any means at all and evolution would still occur.

What is your point with all this?

Randomness is not necessarily acausal. One of the line of reasoning is therefore that none of the definitions of "random" is "acausal".

[Taffer]

I''m sorry, but are you saying that a necessary condition does not provide part of the meaning to its possessor?

Ok, I admit I'm slightly confused. Aren't you claiming that evolution is random, and don't you agree that randomness is acausal?

Randomness is not necessarily acausal. One of the line of reasoning is therefore that none of the definitions of "random" is "acausal".

What? How does that answer my question "what does this mean for evolution?"

[Paul C. Anagnostopoulos]

Sweet Jesus. Not again.
No kidding.

Evolution is a stochastic process, because at least some of the mechanisms involved are stochastic (that is, random). However, it is misleading to call evolution a "random process, full stop" because selection is not random with respect to the local environment.

Note that the definition of random is "not deterministic."

~~ Paul

[Walter Wayne]

Here is a thread to discuss how the word "random" applies, or does not apply, to the Theory of Evolution, depending on how you define the word, and stuff like that.

...

Although, I will admit there are both valid and invalid uses of the term.

Valid usage includes, but might not be limited to:

* Describing mutations where the word "indifferent" could be a substitute. For example, instead of saying "mutations are random to the life form's survival", you could say "mutations are unconsciously indifferent to the life form's survival". (This is more or less the context I have seen Richard Dawkins use.)

"random to the life form's survival" isn't something I've ever heard someone say, and odd since non-random doesn't imply that it isn't indifferent.
* Describing a model of evolution, where our knowledge is not perfect. Such usage implies that the Evolution is actually deterministic behind the scenes. But, information about its initial conditions are lost to time and thermodynamics; and the number of variables involved in the current conditions are too many for us to handle. Therefore, we resort to simplified models that utilize either stochastic algorithms and/or random variables. As the models improve, the less we rely on these things.

I'd agree, but I'd say it can also be used to describe evolution, not just the model for reasons I'll mention later.
Invalid usage includes, but might not be limited to:

* "Random chance", "blind chance", "happy accident", etc. Any term that implies Evolution is all about complete and utter randomness. Evolution is an algorithm, and one that was practically inevitable to crop up somewhere in the Universe (likely more than one place). To imply evolution is random, in this manner, is to misconstrue its nature. In part, because it implies lack of predictive power.

Random chance seems appropriate to me. Random, as I've mention before, does not mean that all possibilities are equal, and I've manage to explain that easily to layman with the simple sum of two dice example. If one acknowledges randomness I wouldn't see an objection to happy chance or bad luck, as in "it was bad luck that apes ever stood upright."

I agree with your objection to blind chance, as it implies that it was unifluenced by surroundings (the environment).

However, while evolution is a process that crops up elsewhere, it is characteristics the constituent processes that make biological evolution what it is. A different means of descent with modification and a selection process unlike our "biosphere" might create a non-random evolution.
* Appeals to quantum uncertainty. While quantum uncertainty might have some small impact on the course of evolution, it would be unfair to "out" Evolution as a theory of randomness because of this, simply because quantum uncertainty makes an impact on all of the other sciences, as well. Also, most quantum fluctuations are averaged out (or "smeared out") in large scales, anyway.
Quantum uncertainty is the engine of mutation. And those mutations have an undeniable and significant impact on the course of biological evolution. The "smeared out" argument doesn't apply because of the vary nature of the biological system. Even if you believe a certain mutation is bound to happen, whether it is beneficial or not depends on the dynamic environment. One that is beneficial at one time, may be deleterious at another. And once a mutation becomes fixed, it influences the environment of those around it.

Biological evolution is not the nicely behaved type of process that we are generally familiar with where variations "average out in the long run".
Your thoughts?
I'd say from the technical point of view, current knowledge implies evolution is random. A particular mutation influences not only the individual it is in, but it influences the environment of individuals around them, possibly affecting there "selection process". This compounding affect will result in large variation at the macro-level rather than the "smearing-out" people are accustommed to discussing.

From the laymans point of view, this will be random in almost every sense I can think of other than that all possibilities are equal. I would go further and state, that even if our knowledge of mutation and selection changed and we found out they were determistic, evolution would still be random in the laymans sense. The innumerable variables were small details can have significant affects would make it "random".

As an example, if it turns out that fundamental particles interactions are determistic in nature, thermal noise while fundamental determistic would be random for all practical purposes.

I agree it is often best to avoid the term, but in most senses biological evolution is random.

Walt

Edited to add: Crap, more text than I intended.

[Walter Wayne]

On the subject of causality, people who deal with the subject of randomness do not equate it with acausal in anyway.

The simplist example off the top of my head is a random number generator. The random action of electrons creates a voltage, which is compared to 0V and a logical "1" or "0" is produced based on whether it is above or below.

The voltage, determined by electron position is said to be random. The logic 1 or 0, generated by the determistic comparator-circuit, is said to be random. This is because no amount of information about the system will tell you the state a few moments from now. The linking of random and acausal is not something that is done by those who actually study such systems.

Walt

[Taffer]

No kidding.

Evolution is a stochastic process, because at least some of the mechanisms involved are stochastic (that is, random). However, it is misleading to call evolution a "random process, full stop" because selection is not random with respect to the local environment.

Note that the definition of random is "not deterministic."

~~ Paul

See, I have no problem with this. It is misleading to call evolution random, full stop. As I said before, random variation could be replaced with designed variation, and evolution would still happen.

I don't quite understand what your point is, mij.

[mijopaalmc]

See, I have no problem with this. It is misleading to call evolution random, full stop. As I said before, random variation could be replaced with designed variation, and evolution would still happen.

I don't quite understand what your point is, mij.

Overall, I want to know how evolution by natural selection is not "random" by the definition "[o]f or relating to a type of circumstance or event that is described by a probability distribution".

In reference to what you and I have been discussing most recently, I am arguing randomness is not necessarily acausal, so evolution by natural selection's possessing a causal structure does not imply in any way that evolution by natural selection is non-random.

[Taffer]

Overall, I want to know how evolution by natural selection is not "random" by the definition "[o]f or relating to a type of circumstance or event that is described by a probability distribution".

In reference to what you and I have been discussing most recently, I am arguing randomness is not necessarily acausal, so evolution by natural selection's possessing a causal structure does not imply in any way that evolution by natural selection is non-random.

Ok. So evolution is random.

So what?

[mijopaalmc]

Ok. So evolution is random.

So what?

It gives us yet another easy way of attacking creationists for abusing scientific terminology.

[ImaginalDisc]

It gives us yet another easy way of attacking creationists for abusing scientific terminology.

But, it doesn't. Evolution is not random. You're still wrong about this.

[mijopaalmc]

But, it doesn't. Evolution is not random. You're still wrong about this.

Any more blind assertions?

Would you care to elaborate on your totally unscientific statement?

Although the really disquieting the terminological debate about is that it show how willing some scientists and science popularizers are to commit the same abuses that creationists do, while deceiving themselves that they are actually helping.

[Belz...]

You're still missing the point (why am I not surprised?:rolleyes:). At no point did either cyborg or I say that acausality was the only characteristic of randomness. However, as cyborg has said several time in the other thread acausality is a necessary condition for randomness.

Mijo, are you by any chance trying to deflect attention by trying to win a minor point on some irrelevant detail ?

[Belz...]

Overall, I want to know how evolution by natural selection is not "random" by the definition "[o]f or relating to a type of circumstance or event that is described by a probability distribution".

Because that would mean that everything is random and that would make the term bloody useless.

[Paul C. Anagnostopoulos]

In reference to what you and I have been discussing most recently, I am arguing randomness is not necessarily acausal, so evolution by natural selection's possessing a causal structure does not imply in any way that evolution by natural selection is non-random.
Could you describe some randomness that is causally based?

~~ Paul

[EHocking]

Any more blind assertions?

Would you care to elaborate on your totally unscientific statement?The statement is neither a blind assertion nor an unscientific one. It is backed by the theory and observation of evolution.

Here is a pretty concise summation: (http://www.pbs.org/wgbh/evolution/library/faq/cat01.html)
Evolution is not a random process. The genetic variation on which natural selection acts may occur randomly, but natural selection itself is not random at all. The survival and reproductive success of an individual is directly related to the ways its inherited traits function in the context of its local environment. Whether or not an individual survives and reproduces depends on whether it has genes that produce traits that are well adapted to its environment.
Although the really disquieting the terminological debate about is that it show how willing some scientists and science popularizers are to commit the same abuses that creationists do, while deceiving themselves that they are actually helping.I can barely parse that sentence, but I hope the above quote might help you on the definition of random when applied to the theory of evolution. Also, find anything written by Richard Dawkins, esp. "The Blind Watchmaker" for a more complete explanation.

[fls]

Just out of curiosity, is the regular appearance of these "Evolution is Not Random" threads for any purpose other than getting mijopaalmc to stop saying it is?

Linda

[sol invictus]

Overall, I want to know how evolution by natural selection is not "random" by the definition "[o]f or relating to a type of circumstance or event that is described by a probability distribution".

I'm pretty sure you finally admitted somewhere that this definition applies to everything in the real world, making it useless. Have you forgotten that? Want me to dig up your quote?

Could you describe some randomness that is causally based?


Semantic debates are soooo boring.

Take 10^23 molecules of gas in a sealed box with volume 1 cubic meter. Start them all moving to the left at 10 m/s, and color one of them red. Where will the red molecule be in an hour?

That system is deterministic and causal (if we ignore quantum mechanics, at least). And yet the question is impossible to answer by any (even hypothetical) means. So, we treat our ignorance the same way we treat fundamental acausality: we call the result random.

[JoeEllison]

Sweet Jesus. Not again.

This thread will come to a bad end.

I promise you that the middle won't be particularly enjoyable either.

[JoeEllison]

Just out of curiosity, is the regular appearance of these "Evolution is Not Random" threads for any purpose other than getting mijopaalmc to stop saying it is?

Linda

No... maybe we should just offer him money?

[UnrepentantSinner]

Just out of curiosity, is the regular appearance of these "Evolution is Not Random" threads for any purpose other than getting mijopaalmc to stop saying it is?

I'll take koans involving equivocation for $800 Alex.

Perhaps those of you who feel it's worth your time to interact with an intransigent might try getting him to accept that mutations are random, but evolution is not. Would that be verbiage he could agree with, or would we still need to clad it in several layers of defining definitions and explaining explanations plus a nice whipped metaphysical topping?

What about it mijo? Would a simple, cut and dried statement like "mutations are random, but evolution is not" be satisfactory for you to give up all the non-sense you've wasted server space with or will you continue to obfuscate and equivocate?

[Belz...]

Take 10^23 molecules of gas in a sealed box with volume 1 cubic meter. Start them all moving to the left at 10 m/s, and color one of them red. Where will the red molecule be in an hour?

That system is deterministic and causal (if we ignore quantum mechanics, at least). And yet the question is impossible to answer by any (even hypothetical) means. So, we treat our ignorance the same way we treat fundamental acausality: we call the result random.

Very well put.

[Wowbagger]

Sorry for the late responses. I have been too busy, and the replies have come too fast, for me to catch up, until now.

Just out of curiosity, is the regular appearance of these "Evolution is Not Random" threads for any purpose other than getting mijopaalmc to stop saying it is? I would, honestly, like to get to the bottom of the issue. If I am wrong about something, and if mijo is right about something, I want it to come out, now!

These threads may be painful for some folks, but at least we can try to get to the bottom of this now, so if the subject erupts again, we can refer to this thread (or maybe its best posts). In the meantime, we won't interrupt any other threads with this battle.

Sweet Jesus. Not again.

This thread will come to a bad end. No doubt.

I've always thought that "random" either means we have not enough information to predict the outcome or that it implies acausal processes. That is one of my valid usages.

The first two are, perhaps, covered by the point above; their result is, indeed, indifferent to the survival of the individual sufferer. The third, being a naturally occurring random process, is not covered, but needs to be; it is the major "reason" for sexual reproduction being a valuable process to a genome. And it make cats interesting, as well. I see no reason why gene shuffling could not be covered by the valid usages, above. You could think of it as just another "mutation", but one controlled by the genome itself. An adaptation of adaptability.

I would say that evolution as a process harnesses random events (mutations) as a means of generating variety. That is one way to put it.

Though, "harness" sounds like there is conscious intention involved. As long as it is understood not to be the case, the verbiage is otherwise fine, in my opinion.

I'd say that mutation is random within limits. If you mutate too much, or against selective pressure, you can't have kids. If you mutate too little, or get "locked inside" a specialized biological niche, you can't adapt to changes in the enviroment. Yes, average mutation rate could well have emerged out of the process of evolution, because of such selection pressures.

I think a better word for the things most people call 'random' would be 'chaotic'. In the sense of Complexity Theory, you would be right. And, that would be part of my second valid usage.

Though, I am not sure I like using the word "chaotic", because it has lots of other meanings on its own, and would be bound to cause confusion among the masses.

Evolution is a stochastic process, because at least some of the mechanisms involved are stochastic (that is, random). However, it is misleading to call evolution a "random process, full stop" because selection is not random with respect to the local environment. Correct.

Note that the definition of random is "not deterministic." That is just one definition, and is one I consider invalid towards describing Evolution.

"random to the life form's survival" isn't something I've ever heard someone say, and odd since non-random doesn't imply that it isn't indifferent. Here is a quote from Richard Dawkins, in his essay "Darwin Triumphant", which can be found in his book A Devil's Chaplain:

Mutations are, of course, caused by physical events, for instance, cosmic ray bombardment. When we call them random, we mean only that they are random with respect to adaptive improvement.

It is my own contribution to use the words "unconsciously indifferent", because I think it is less confusing than "random", to the average person, in this context.

Random chance seems appropriate to me. Random, as I've mention before, does not mean that all possibilities are equal, and I've manage to explain that easily to layman with the simple sum of two dice example. If one acknowledges randomness I wouldn't see an objection to happy chance or bad luck, as in "it was bad luck that apes ever stood upright." "Luck" too is subjective to human bias.

The patterns of biological convergence seems indicative that evolution is not best modeled as random chance.

"Random chance" is wholly inadequate to describe stuff like this:
http://www.sciencedaily.com/releases/2007/11/071119123929.htm

Quantum uncertainty is the engine of mutation. And those mutations have an undeniable and significant impact on the course of biological evolution. The "smeared out" argument doesn't apply because of the vary nature of the biological system. The fact that we see similar solutions evolve in life forms facing similar selection pressures, (within their survival strategy niche) indicates that the "smeared out" argument certainly does apply.

From the laymans point of view, this will be random in almost every sense I can think of other than that all possibilities are equal. If that were true, Evolution would cease to have predictive powers, and utterly fail as a valuable scientific theory. We would do just as well by rolling appropriately-sided dice.

Evolution is better than random dice rolls, because it describes an algorithm of natural selection. And, one that seems to work pretty well, so far.

The innumerable variables were small details can have significant affects would make it "random". This is covered by the second valid usage in my first post.

I'd like to point out that Arthur Dent's daughter, being responsible for the extinction of human kind and all other earth species, is by no means a bit player in evolution. But, unless you are living in a universe controlled by such reverse temporal engineering technologies, it would be useless to describe Evolution in terms of "Random Dents".


Here is a pretty concise summation: (http://www.pbs.org/wgbh/evolution/library/faq/cat01.html)
Evolution is not a random process. The genetic variation on which natural selection acts may occur randomly, but natural selection itself is not random at all.
(snip) It's good to have these summations, in threads like this. I was going to write my own, but I figured the opening post was long enough.
Thanks!

So, we treat our ignorance the same way we treat fundamental acausality: we call the result random. ...in the sense of the second valid usage I wrote about. Yes.

Perhaps those of you who feel it's worth your time to interact with an intransigent might try getting him to accept that mutations are random, but evolution is not. Would that be verbiage he could agree with, or would we still need to clad it in several layers of defining definitions and explaining explanations plus a nice whipped metaphysical topping? Well, it would be a start!

[Paul C. Anagnostopoulos]

Take 10^23 molecules of gas in a sealed box with volume 1 cubic meter. Start them all moving to the left at 10 m/s, and color one of them red. Where will the red molecule be in an hour?

That system is deterministic and causal (if we ignore quantum mechanics, at least). And yet the question is impossible to answer by any (even hypothetical) means. So, we treat our ignorance the same way we treat fundamental acausality: we call the result random.
Yes, but what I want from Mijo is a random process that is causally based, using the actual definition of random, not a folk definition.


That is just one definition, and is one I consider invalid towards describing Evolution.
You gots some other definition of random?

~~ Paul

[Wowbagger]

You gots some other definition of random? Well, there are five bullet points in my opening post...



Perhaps it might pay to clarify these things, for those who need it:

Mitchell's definitions of Random (summarizing the bullet points in the OP):
1. Analagous to "indifferent"
2. A stochastic model
3. A "happy accident"
4. Quantum uncertainty
5. Arthur Dent's daughter

There could be others.

[mijopaalmc]

Mijo, are you by any chance trying to deflect attention by trying to win a minor point on some irrelevant detail ?

It's not a minor point when people get seemingly incensed at me for engaging in a "semantic argument" when I argue that evolution is mathematically random but then they insist they didn't say "random means acausal" based on a sematic argument.

[mijopaalmc]

Because that would mean that everything is random and that would make the term bloody useless.

No it doesn't. If you bothered to actually examine what the mathematical definitions of "random" and "deterministic", you would see that "random" means that identical initial condition don't always yield identical final conditions, whereas "deterministic" means that identical initial condition always yield identical final conditions. The problem is that, depending on how we define the initial conditions, we may have trouble measuring the initial conditions with arbitrary precision, making it impossible to determine whether the system is random or chaotic (i.e., deterministic, but sensitively dependent on initial conditions).

[mijopaalmc]

Could you describe some randomness that is causally based?

~~ Paul

Mutations: they don't "just happen". For instance, ionizing radiation causes two pyrimidine dimers to dimerize which causes a transcription error.

[Ron_Tomkins]

The only problem I have with the word random is that when it comes to use it with the general public, it tends to trigger the typical negative reaction:

"Oh so you're just saying that everything that is, is nothing but the consequence of a bunch of random events?? I can't believe you want me to swallow that"

And then they throw the one about the airplane parts and the tornado that can't randomly build a plane and blablabla.

So the word random needs to be either dismantled and re-defined or replaced by a different word, such as " chaotic" (already mentioned here).

[Almo]

Though, "harness" sounds like there is conscious intention involved. As long as it is understood not to be the case, the verbiage is otherwise fine, in my opinion.

Yes, you're absoulutely right.

[Ichneumonwasp]

It's not a minor point when people get seemingly incensed at me for engaging in a "semantic argument" when I argue that evolution is mathematically random but then they insist they didn't say "random means acausal" based on a sematic argument.

Actually it is a minor point. And it is semantics.

This is precisely what happens when you take terminology from one area of discourse and introduce it into another area for which it wasn't devised. It will stick if it is useful. Right now, it doesn't seem useful for anything beyond derailing existing threads and generating new threads to rehash the same old arguments.

[Wowbagger]

The only problem I have with the word random is that when it comes to use it with the general public, it tends to trigger the typical negative reaction:

"Oh so you're just saying that everything that is, is nothing but the consequence of a bunch of random events?? I can't believe you want me to swallow that"

And then they throw the one about the airplane parts and the tornado that can't randomly build a plane and blablabla. Exactly!

All those examples fall into the "happy accident" category, in the opening post.

Yes, you're absoulutely right.
Sometimes you can't help it. I've read about how birds "calculate the most effective ratio of egg-count to yolk-content", for example. It doesn't mean the birds are really consciously calculating anything. It just means that, over time, genes that were more prone to result in effective ratios have emerged through selection pressures.

We still use the terms "sunrise" and "sunset" even though we know better.

[jimbob]

Just out of interest:

Are there any chaotic physical systems that wouldn't be significantly influenced by quantum uncertanites given enough time?

Yes, but what I want from Mijo is a random process that is causally based, using the actual definition of random, not a folk definition.

Would the drunkard's walk (http://en.wikipedia.org/wiki/Random_walk) count? (or at least the mathematical concept of the drunkard's walk)

ETA: Thinking about it, probably no...

[mijopaalmc]

Actually it is a minor point. And it is semantics.

This is precisely what happens when you take terminology from one area of discourse and introduce it into another area for which it wasn't devised. It will stick if it is useful. Right now, it doesn't seem useful for anything beyond derailing existing threads and generating new threads to rehash the same old arguments.

Actually, scientists (including evolutionary biologists) use the definition of "random" that I use every time the perform a statistical test, so I don't see what the problem is with applying it to yet another object of study.

[mijopaalmc]

So the word random needs to be either dismantled and re-defined or replaced by a different word, such as " chaotic" (already mentioned here).

But "chaotic" does not mean "random". A chaotic system is by definition deterministic but sensitively dependent of initial conditions. A random system is by definition not deterministic.

[JoeTheJuggler]

Another valid use of "random" is to mean "directionless". I'd prefer a more accurate term like "directionless".

Evolution does not have any goal or end point. Knowing any given "starting" point will not enable you to predict future forms. (Remember the Twilight Zone episode with the machine that let you "fast forward" or "rewind" evolution? Yeah--that's not right in the least.)

The story of the evolution of the modern horse, for example, is not accurately portrayed as starting with a smaller animal with more toes and somehow trying to perfect that form as the modern horse by selecting larger animals with fewer toes.

[Taffer]

Actually, scientists (including evolutionary biologists) use the definition of "random" that I use every time the perform a statistical test, so I don't see what the problem is with applying it to yet another object of study.

Can you elaborate on this? How exactly are these random elements included in said statistical tests?

[Earthborn]

So the word random needs to be either dismantled and re-defined or replaced by a different word, such as " chaotic" (already mentioned here).The average person is not likely to know the scientific definition of "chaotic" either. I don't think it will make much difference to say "chaotic" instead of "random". Perhaps it is even worse; when you say "random" you can explain how many random events sometimes lead to predictable outcomes, such as casino owners getting richer. The term "chaotic" conjures up associations that pretty much anything can happen, no matter how wild and unlikely.

Wowbagger's favourite term "unconciously indifferent" will evoke a "Huh? What?" to most people. The word "indifferent" has the connotation of a person not caring about about something he could care about. Wowbagger needs feels the need to add "unconciously" to it in a futile attempt to remove the connotation, but it only makes the term an oxymoron.

Let's not forget that many people have a bit of a problem understanding what is mean with the word "theory" in "Theory of Evolution". Replacing words for complex scientific concepts with other words is not going to give the general public a better understanding of the science. The scientific concepts are non-intuitive, and there simply are no everyday words that are commonly understood by non-scientists that accurately describe them.

Using the word "random" to describe evolution is fine, but in popular science texts perhaps need to be explained what is meant with it. It doesn't mean that in a given environment all organisms have an equal chance of survival; some are more likely to 'win' than others. But because random events play a role in shaping organisms and their environments, organisms play a role in shaping their environments and environments play a role in shaping organisms, if evolution had taken a slightly different route early on, things would have looked very differently today. We really are the result of many rolls of God's* dice.

* 'God' in the metaphorical and not necessarily in the metaphysical sense...

[mijopaalmc]

Can you elaborate on this? How exactly are these random elements included in said statistical tests?

Have you ever taken a statistics course?

The null hypothesis is most often assumed to yield a certain distribution, and then the sample statistic is tested against this distribution, which in turn determines probability of the null hypothesis being true given the data collected due purely to variations in the sample.

[Paul C. Anagnostopoulos]

Mitchell's definitions of Random (summarizing the bullet points in the OP):
1. Analagous to "indifferent"
2. A stochastic model
3. A "happy accident"
4. Quantum uncertainty
5. Arthur Dent's daughter
I understand 2 and 4, which are the same thing. What are the other three?

~~ Paul

[Paul C. Anagnostopoulos]

Mutations: they don't "just happen". For instance, ionizing radiation causes two pyrimidine dimers to dimerize which causes a transcription error.
But the ionizing radiation is random with respect to which base is affected. So a random event triggers a deterministic chemical process.

This is exactly why it is confusing to say "evolution is random, full stop."

~~ Paul

[jimbob]

Evolution is a stochastic process, because at least some of the mechanisms involved are stochastic (that is, random). However, it is misleading to call evolution a "random process, full stop" because selection is not random with respect to the local environment.

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.

[mijopaalmc]

But the ionizing radiation is random with respect to which base is affected. So a random event triggers a deterministic chemical process.

But you have to follow a chain of causality backward to get to the actual acausal event. If it is in appropriate to call evolution by natural selection because mutations are random, why is it appropriate to call mutation acausal because the production of ionizing radiation (or base tautomerization) is acausal?

This is exactly why it is confusing to say "evolution is random, full stop."

Where have I ever said that it was not confusing to say "evolution is random, full stop"?

[Paul C. Anagnostopoulos]

So the word random needs to be either dismantled and re-defined or replaced by a different word, such as " chaotic" (already mentioned here).
But a chaotic process is not a random process.

~~ Paul

[mijopaalmc]

Wowbagger-

Why are you trying to define "random" is such a way that it if precluded from being random by definition?

[Paul C. Anagnostopoulos]

But you have to follow a chain of causality backward to get to the actual
acausal event. If it is in appropriate to call evolution by natural
selection because mutations are random, why is it appropriate to call
mutation acausal because the production of ionizing radiation (or base
tautomerization) is acausal?
I can't quite parse this. Could you reword it?


Where have I ever said that it was not confusing to say "evolution is
random, full stop"?
Way back when all this started. Or was it someone else? As I've said before, I have no idea where you're going with this.

~~ Paul

[jimbob]

Wowbagger, I would partially take issue with this "invalid description" in your OP:

* Appeals to quantum uncertainty. While quantum uncertainty might have some small impact on the course of evolution, it would be unfair to "out" Evolution as a theory of randomness because of this, simply because quantum uncertainty makes an impact on all of the other sciences, as well. Also, most quantum fluctuations are averaged out (or "smeared out") in large scales, anyway.

Mutations, that have a selective effect (advantageous or disadvantageous) must affect the selective landscape for other organisms in the ecosystem. Which mutations occur first could affect the "direction" of the selective pressures.

My expansion on the other thread below:

If identical conditions do not lead to the same outcome every time, then I would consider that to be a working definition of "random".

Agreed.

I would argue that a quantum decay event is the archetypal "random event".

Also agreed.

In the context of evolution, I would argue that because weather is a highly nonlinear system, quantum events can be magnified to have a significant effect on the weather. If this is the case, then there is going to be a random element in natural selection. I would also argue that the relationships between organisms is even more nonlinear than the weather, and a chance mutation happening befoore anonther could alter the selective pressures on other organisms within the ecosystem, and thus alter the "direction" of evolution in the ecosystem.

If we assume weather to be affected at a significant level by quantum events, I would agree with you. I also agree that interorganism interactions are very complex, and specific mutation events are boardering on quantum randomness. Of course, we don't know that for certain, but so far that is how it looks.

This means that should one have the luxury of creating identical universes just before the KT impact, the course of evolution in each of these initially identical universes would diverge.

Agreed.

Given the low chance of any individual organism managing to have reproducing offspring, I would contend that there was noting inevitable about the emergence of hominids, until some time after the last common ancestor with apes.

Agreed.

Evoulution would happen in all the other cases, it is just that the species mix, and indeed occupied niches would probably differ in each case. There is nothing special abut the emergence of humanity, except to us...

Yep, couldn't put it better myself.

Walter Wayne, this is a perfect example of what I asked for.

I can think of one (convoluted) mechanism where quantum events should affect the weather. A radioactive decay event causs a cancer that kills an animal prematurely. This is no longer wandering around, so that is definitly of a size to affect weather patterns. Of course it actually looks as if weather patterns should be directly affected by quantum events too. But, I believe it is not confirmed yet.



On to the statement about predictions:

I'd say that we can make certain predictions with a high level of confidence.

If there are steady selective pressures, then there will be a steady "direction" to the evolution. A classic case being the experiments with heat tolerance of e-coli colonies.

However the mechanism ofr this adaptaiton is not predetermined. A classic case being the experiments with heat tolerance of e-coli colonies, when moved to cool environments: most of the heat-adapted strains did worse than the parental strains, but some did better, they had evolve different mechanisms that gave improved heat-tolerence.

We can make predictions about drug resistance too.

In the wider world we can make predictions about particular niches that are likely to be filled. (Large herbivore, predator of large herbivore, parisites of these animals for example).

We can also state that sight and flight are traits that are advantageous enough to have evolved independently many times, so these are likely to occur in suitable ecosystems.

Conversely, should the need for flight vanish (for example in an isolated island) the energy costs would make flight a disadvantageous trait, and so you would expect to see flightless animals that had flying ancestors.

What you can't predict is how future evolved organisms will interact, and how these will modulate the selective pressures.

Catastrophic events, e.g. the KT impact also have the effect of clearing out many niches, sometimes removing them completely and creating others, essentially Year-Zero. Large carnivores and large herbivores, but a triceritops isn't a rhino...

[mijopaalmc]

I can't quite parse this. Could you reword it?

The most common argument against evolution by natural selection's being random is that mutation is random but natural selection isn't. Therefore, one cannot appeal to the randomness of mutation to say that evolution by natural selection is random. You seem to be arguing that mutation is acausal because the things that ultimately cause it are acausal.

Isn't your argument regarding acausality and mutation both self-contradictory and inconsistent in light of your argument regarding randomness and evolution?

Way back when all this started. Or was it someone else?

You might want to check this post out for my position on saying "evolution is random, full stop":

You can't possibly be serious:eye-poppi. This comment implies that you have not actually read anything that or anyone else who claims that evolution is random has written. I specifically cited Split from: I'm reading "The God Delusion" - a review in progress (http://forums.randi.org/showthread.php?t=80924) because there are several posts that give dictionary definitions of "random" (#47 (http://forums.randi.org/showthread.php?p=2568546#post2568546), #49 (http://forums.randi.org/showthread.php?p=2568732#post2568732)) and discuss why all but the mathematical and statistical definition do not describe evolution (#65 (http://forums.randi.org/showthread.php?p=2571760#post2571760), #69 (http://forums.randi.org/showthread.php?p=2571807#post2571807), #71 (http://forums.randi.org/showthread.php?p=2571872#post2571872), #73 (http://forums.randi.org/showthread.php?p=2571994#post2571994),
#75 (http://forums.randi.org/showthread.php?p=2572320#post2572320)). I also made it quite clear that I favored "stochastic" or "probabilistic" over "random" because they have very specific definitions that avoid the common associations and therefore misinterpretations of "random" (#103 (http://forums.randi.org/showthread.php?p=2598575#post2598575), #189 (http://forums.randi.org/showthread.php?p=2606912#post2606912), #234 (http://forums.randi.org/showthread.php?p=2609996#post2609996), #252 (http://forums.randi.org/showthread.php?p=2611299#post2611299)). Furthermore, I explained in great detail several times in this thread exactly why evolution is probabilistic or stochastic (#158 (http://forums.randi.org/showthread.php?p=2606116#post2606116), #230 (http://forums.randi.org/showthread.php?p=2609885#post2609885)).

[Ichneumonwasp]

Actually, scientists (including evolutionary biologists) use the definition of "random" that I use every time the perform a statistical test, so I don't see what the problem is with applying it to yet another object of study.

I didn't say there was anything wrong with it, just that this is what happens. When words are used across disciplines they create some controversy. Useful words continue to be used and words that don't work well die.

We don't know about this word yet. The only problem that anyone has with it is that it is used as a strawman argument by creationists, as you know, so it has created a maelstrom here.

I think we all have a pretty good idea about the underlying processes, so the only real controversy is whether or not to use this particular word. I guess part of the issue comes from folks worried that ideas that don't fit are being jammed into the 'random' carton, but really, it's just a word.

[Paul C. Anagnostopoulos]

The most common argument against evolution by natural selection's being random is that mutation is random but natural selection isn't. Therefore, one cannot appeal to the randomness of mutation to say that evolution by natural selection is random. You seem to be arguing that mutation is acausal because the things that ultimately cause it are acausal.
I have no idea what you're trying to say here. Why can't I appeal to the randomness of mutation to argue that evolution is a random process?

Isn't your argument regarding acausality and mutation both self-contradictory and inconsistent in light of your argument regarding randomness and evolution?
What do you think my argument about randomness and evolution is? It's nothing more than suggesting that "evolution is random" is a misleading statement. I didn't say "incorrect," just "misleading."


You might want to check this post out for my position on saying "evolution is random, full stop":
I must have had you confused with someone else.

~~ Paul

[Paul C. Anagnostopoulos]

Here we go:

http://www.puc-rio.br/marco.ind/stoch-a.html


Following Dixit & Pindyck's textbook (p.60): "Stochastic process is a variable that evolves over time in a way that is at least in part random".


And then the definition of pure random process:

http://stats.oecd.org/glossary/detail.asp?ID=3807

Evolution is a stochastic process, but not a pure random process. I believe that when most people hear "random process" they think "pure random process."


~~ Paul

[Meadmaker]

Sweet Jesus. Not again.

This thread will come to a bad end.


If we're lucky. It might not end.

(And of course, after I read more of it, I'll probably comment.)

[mijopaalmc]

I'll take koans involving equivocation for $800 Alex.

Perhaps those of you who feel it's worth your time to interact with an intransigent might try getting him to accept that mutations are random, but evolution is not. Would that be verbiage he could agree with, or would we still need to clad it in several layers of defining definitions and explaining explanations plus a nice whipped metaphysical topping?

What about it mijo? Would a simple, cut and dried statement like "mutations are random, but evolution is not" be satisfactory for you to give up all the non-sense you've wasted server space with or will you continue to obfuscate and equivocate?

It's always funny when the people who insist that I am obfuscating and equivocation are the ones what are actually obfuscating and equivocating.

I think Vorticity said it best way back in May of last year:

Here's another thing that's been bugging me:
...
If a series of coins are tossed that have a 50/50 chance of coming up heads or tails, but only those that come up heads are selected to be placed in a piggy bank and the coins that come up tails are thrown into a river, then the results of the selection process are not random.
This idea has been stated in several forms in this thread, i.e. that while the mutation process is certainly random, the process of natural selection by which less-well-adapted variants are culled from the population is deterministic.

This seems to me to be a highly dubious claim. I'm having trouble seeing how the natural selection process could be completely deterministic. Certainly, the more-well-adapted variants will have a higher chance of surviving and reproducing. Perhaps siginificantly higher. Likewise, a poorly-adapted variant will have a much higher chance of becoming lunch. But it's not a certitude. These probabilities are not 1 and 0.

To put it another way, suppose we know the set of gene/allele frequencies of a population in a given generation. Even if we suppose that no mutation events will occur between this generation and the next, we cannot in advance specify the precise gene/allele content of the next generation. There is still significant randomness left over. Who will be eaten, who will reproduce, how much will they reproduce, etc. Now of course this is a sort of 'directed randomness', in the sense that the more adapted variants have a much better chance. But this does not suddenly make it nonrandom.

I repeated this sentiment in my OP in What evidence is there for evolution being non-random?:

The title of the thread says it all. I understand that evolution is a process directed through natural selection, but, as I understand it, natural selection is based on the probability, not certainty, of an organism with a specific "fitness complement" (i.e., the set of genes that contribute to its survival and reproduction relative to others of the same species). An individual whose fitness complement confers a greater chance of survival and reproduction is only more likely to survive and reproduce that one with a fitness complement that a lesser chance, but the survival and reproduction is not determined to such an extent that all the individuals with a specific fitness complement don not survive and reproduce. Thus, it is possible for one individual with a certain fitness complement to survive while another individual with the same fitness complement doesn't.

I only ask this, because I am thoroughly disappointed in the evidence that I have received from the posters in this thread (http://forums.randi.org/showthread.php?t=80924). No-one to my knowledge has either explained how a process that operates on probability is non-random or directed me toward a resource that does. They all seem to be more interested, as is most of the literature on the internet that doesn't specifically deal with non-random genetic processes such as mutation and unequal cross over, in refuting the creationist straw man that holds that organisms in their current state are far too complex to have arisen by chance.

I would appreciate it if someone could point me toward some literature (especially of the peer-reviewed kind)that explain clearly and concisely why evolution is non-random.

Thus far, I have only received responses that explain why evolution is non-random in every other way than the way in which I defined it, which is equivocation on the part of the respodants.

[Wowbagger]

Are there any chaotic physical systems that wouldn't be significantly influenced by quantum uncertanites given enough time? None that I can think of. Which is why it is futile to single Evolution out as random for that reason. Everything would be random in that way, and so the word becomes meaningless, in that context.

Another valid use of "random" is to mean "directionless". I'd prefer a more accurate term like "directionless". I can agree with that! Perhaps "directionless" would be better than "unconsciously indifferent"?

Wowbagger's favourite term "unconciously indifferent" For the record, my favorite term happens to be "paredolia", which is followed closely by "The Tyranny of a Discontinuous Mind", "psychological neotny", and then "hoopy frood". I would say "unconsciously indifferent" probably ranks somewhere towards the bottom of the Top 200 list.

The word "indifferent" has the connotation of a person not caring about about something he could care about. Wowbagger needs feels the need to add "unconciously" to it in a futile attempt to remove the connotation, but it only makes the term an oxymoron. Not necessarily. What I mean is "Not just indifferent, but indifferent in the way only a cold, unconscious thing could be."

The scientific concepts are non-intuitive, and there simply are no everyday words that are commonly understood by non-scientists that accurately describe them. We can at least try. And, it might be better to experiment with language, here, before using phrases in a more formal manner.

What do you think of "directionless" as a substitute for "indifferent"?

Using the word "random" to describe evolution is fine, but in popular science texts perhaps need to be explained what is meant with it. I agree with that. Though, that does not mean the readers are going to pick up on it. One look at the word "random", and they will automatically assume they know what it means, and ignore the explanation.

I understand 2 and 4, which are the same thing. What are the other three? I would say 2 and 4 are related to each other, but not the same thing. Not all variables in a stochastic model are precise enough to reach the quantum level.

In the OP, it should be clear why I separated them out. It is valid to use stochastic models to help us describe Evolution. However, it would be invalid to dismiss it as invalid due to quantum uncertainty, because every other science would then be "invalid" in the same way. And, yet, we all know all the legit sciences work pretty darn well, in spite of that.

The other three are just other uses of the term, that I have seen around.

I think definition #3 could better be summarized as "pure random", incidentally.

Why are you trying to define "random" is such a way that it if precluded from being random by definition?Correct me if I am wrong, but I do think I am using the word in a similar manner as you, in the second bullet point about stochastic processes.

If I am wrong, then please inform me of how your definition is different. (And, optionally, how that difference is relevant to Evolution, if at all.)

Mutations, that have a selective effect (advantageous or disadvantageous) must affect the selective landscape for other organisms in the ecosystem. Which mutations occur first could affect the "direction" of the selective pressures. I agree with that, but fail to understand how that is an objection to the bullet point you quoted.

On to the statement about predictions:
(snip) Exactly! And, of course, all those examples you gave work against the idea of Evolution being purely random. The Creationists don't know what they're missing!

If we're lucky. It might not end. I think I might be a gluten for punishment.

[Taffer]

Have you ever taken a statistics course?

Yes. They were a requirement for my degree.

The null hypothesis is most often assumed to yield a certain distribution, and then the sample statistic is tested against this distribution, which in turn determines probability of the null hypothesis being true given the data collected due purely to variations in the sample.

That is how hypotheses are tested against a null hypothesis. You said that randomness, as you have defined it, was used in the specific statistical tests used for evolutionary biology. I don't dispute this. What I dispute is that your definition is the one used, since it makes no difference to the tests. Further, we test AGAINST a random null hypothesis, to show that the data is not random.

[mijopaalmc]

Correct me if I am wrong, but I do think I am using the word in a similar manner as you, in the second bullet point about stochastic processes.

If I am wrong, then please inform me of how your definition is different. (And, optionally, how that difference is relevant to Evolution, if at all.)

Here is your bullet point:

* Describing a model of evolution, where our knowledge is not perfect. Such usage implies that the Evolution is actually deterministic behind the scenes. But, information about its initial conditions are lost to time and thermodynamics; and the number of variables involved in the current conditions are too many for us to handle. Therefore, we resort to simplified models that utilize either stochastic algorithms and/or random variables. As the models improve, the less we rely on these things.

You are quite explicit that your are intent on only describing the models as stochastic and not the actual process of evolution by natural selection. I, on the other hand, think that the way evolutionary biologists describe the process of evolution by natural selection as it occurs in the physical world is inherently stochastic (and not necessarily just because of out lack of knowledge of the details of the process) and that the existing data that we have corroborates this interpretation.

[sol invictus]

Thus far, I have only received responses that explain why evolution is non-random in every other way than the way in which I defined it, which is equivocation on the part of the respodants.

That's because your definition is totally useless, as we already established in that other horrible thread.

It also doesn't correspond to any of the 10 or so definitions from various sources which were posted there, including the one from a standard text on probability and statistics.

[mijopaalmc]

That is how hypotheses are tested against a null hypothesis. You said that randomness, as you have defined it, was used in the specific statistical tests used for evolutionary biology. I don't dispute this. What I dispute is that your definition is the one used, since it makes no difference to the tests. Further, we test AGAINST a random null hypothesis, to show that the data is not random.

I'm sorry but that is how hypotheses are tested. For a parametric test, the statistic defines a tail on the distribution for which the null hypothesis true just by the variation in the sample. The p-value is then the area in the tail, which translates to the probability that the null hypothesis is true by the variation in the sample. If p-value is greater than the confidence level, the null hypothesis cannot be rejected. If p-value is less than the confidence level, the null hypothesis is rejected.

[mijopaalmc]

That's because your definition is totally useless, as we already established in that other horrible thread.

It also doesn't correspond to any of the 10 or so definitions from various sources, including the one from a standard text on probability and statistics.

And where did you provide these examples?

For instance the definition you provided from the Oxford English Dictionary does in fact back up my definition from the American Heritage Dictionary:

random, n., a., and adv.

<snip noun definitions>

B. adj. (from phr. at random: see A. 3).

1. a. Not sent or guided in a special direction; having no definite aim or purpose; made, done, occurring, etc., at haphazard.

b. Statistics. Governed by or involving equal chances for each of the actual or hypothetical members of a population; also, produced or obtained by a random process (and therefore completely unpredictable in detail); random distribution, a probability distribution, esp. the Poisson distribution; random error: see ERROR 4d; random noise (see quot. 1954); random number, a number selected from a given set of numbers in such a way that all the numbers in the set have the same chance of selection; also, a pseudorandom number; random process, (a process characterized by) a sequence of random variables (see also quot. 1937); random sample, a sample drawn at random from a population, each member of it having an equal or other specified chance of inclusion (sometimes contrasted with quota sample s.v. QUOTA n. 4); so random sampling; random selection, a random sample; random sampling; random variable, variate, a variable whose values are distributed in accordance with a probability distribution; random walk, the movement of something in successive steps, the direction, length, or other property of each step being governed by chance independently of preceding steps.

The Poisson distribution is not in anyway uniform, so can't be properly described by the first sense in 4, so it must be random by some other metric.

[sol invictus]

Dear god.

Really? So why not name one?

Every single example you gave was a mathematical model. Should I remind you (again) of what they were? One particularly entertaining one was "orbital dynamics", by which you meant the ideal N body problem with only classical Newtonian gravity acting.



Nowhere in there is a definition of random, let alone one like yours. I just checked two books on probability on amazon using booksearch. Neither appears to define "random" (although both use the word quite a lot).

Here are a long list of web definitions, not a single one of which comes even close to yours:

http://www.google.com/search?q=define%3A+random

[mijopaalmc]

Dear god.

Really? So why not name one?

Every single example you gave was a mathematical model. Should I remind you (again) of what they were? One particularly entertaining one was "orbital dynamics", by which you meant the ideal N body problem with only classical Newtonian gravity acting.



Nowhere in there is a definition of random, let alone one like yours. I just checked two books on probability on amazon using booksearch. Neither appears to define "random" (although both use the word quite a lot).

Here are a long list of web definitions, not a single one of which comes even close to yours:

http://www.google.com/search?q=define%3A+random

Congratulations, you managed to find merely the most commonly used definition of "random" (and probably the only definition of "random" used on those sites) and are now trying to pass it off as only definition in use in the English language.

[UnrepentantSinner]

I think I might be a gluten for punishment.

I'll strand by you.

[mijopaalmc]

Does anyone else recognize that "evolution by natural selection is random (stochastic)" and "evolution by natural selection is a random (stochastic) process" could mean different things?

[Paul C. Anagnostopoulos]

Does anyone else recognize that "evolution by natural selection is random (stochastic)" and "evolution by natural selection is a random (stochastic) process" could mean different things?
Since evolution is a process, I don't see how they could mean different things. But I'm willing to learn.

~~ Paul

[cyborg]

I said it before and I'll say it again:

Variation is non-deterministic with respect to form.
Selection is deterministic with respect to form.

It does not matter ONE BIT whether or not that variation is caused by quantum mechanics, a die roll, a list of numbers, or even, horrors, a deterministic process, etc.. the important part is the deterministic relationships.

If variation is based on form then mutation is not the mechanism of change in form - previous forms are.

If selection is not based on form then what variations arise are inconsequential to what forms persist.

These are the basic and fundamental conditions that must be satisfied for any system that would be considered "evolutionary" - be it biological or a abstract model.

NOTA BENE deterministic with respect to is not the same as wholly determined by - yes mijo, I am thinking of you and your twins. Their form does not wholly dictate their selection but to argue that their selection is not deterministic with respect to it would be WRONG.

[sol invictus]

Congratulations, you managed to find merely the most commonly used definition of "random" (and probably the only definition of "random" used on those sites) and are now trying to pass it off as only definition in use in the English language.

So mijo, you really don't remember that long and excruciatingly annoying discussion we had in the "Evolution Not Random" thread about how your definition is useless, since according to it every single process in the world is random?

Strange, because here you are in a different thread more recently parroting almost verbatim what I was telling you there all along:

Except, to the best our knowledge, quantum mechanical events are random no matter how you try to constrain the variables. While it is mathematically true that a function of a random variable is itself a random variable*, it is not very useful in describing real world physical processes, because every actual physical process is based on quantum mechanics. However, it still important to make a distinction between non-chaotic deterministic systems (i.e., roughly systems in which small variations in initial conditions lead to small variations in final conditions) and chaotic deterministic systems (i.e., roughly systems in which small variations in initial conditions lead to large variations in final conditions). Evolution is most likely the latter because it takes place in a in an environment that is dependent on other chaotic systems (e.g., climate and weather). This means that exact predictions cannot be made about specific elements of adaptation, whereas predictions about the general course of adaptation can be made and are best handled in a probabilistic/statistical framework.

*meaning that random mutation based on probability leads to random evolution by natural selection regardless of whether natural selection itself is random or deterministic

[Taffer]

I said it before and I'll say it again:

Variation is non-deterministic with respect to form.
Selection is deterministic with respect to form.

It does not matter ONE BIT whether or not that variation is caused by quantum mechanics, a die roll, a list of numbers, or even, horrors, a deterministic process, etc.. the important part is the deterministic relationships.

If variation is based on form then mutation is not the mechanism of change in form - previous forms are.

If selection is not based on form then what variations arise are inconsequential to what forms persist.

These are the basic and fundamental conditions that must be satisfied for any system that would be considered "evolutionary" - be it biological or a abstract model.

NOTA BENE deterministic with respect to is not the same as wholly determined by - yes mijo, I am thinking of you and your twins. Their form does not wholly dictate their selection but to argue that their selection is not deterministic with respect to it would be WRONG.

There was a farmer, had a dog, and...

[Taffer]

I'm sorry but that is how hypotheses are tested. For a parametric test, the statistic defines a tail on the distribution for which the null hypothesis true just by the variation in the sample. The p-value is then the area in the tail, which translates to the probability that the null hypothesis is true by the variation in the sample. If p-value is greater than the confidence level, the null hypothesis cannot be rejected. If p-value is less than the confidence level, the null hypothesis is rejected.

I'm sorry, but that's not what I'm arguing about. I'm arguing about whether your definition of random is important in statistics.

[jimbob]

Are there any chaotic physical systems that wouldn't be significantly influenced by quantum uncertanites given enough time? None that I can think of. Which is why it is futile to single Evolution out as random for that reason. Everything would be random in that way, and so the word becomes meaningless, in that context.

There are non-chaotic physical systems where this isn't the case. The key word is "significantly".

I design and develop power transistors; these rely on the law of large numbers to average out quantum uncertainties, which make them work with very large numbers of electrons. Because they are power devices, they have to be large enough to manage high electric fields, so "normal" semiconductor physics (dealing with conduction bands and Fermi-Dirac statistics is valid, in a way that is getting less so for very small devices.)


Mutations, that have a selective effect (advantageous or disadvantageous) must affect the selective landscape for other organisms in the ecosystem. Which mutations occur first could affect the "direction" of the selective pressures. I agree with that, but fail to understand how that is an objection to the bullet point you quoted.

I would argue that this means that the selection pressures, and thus the "direction" of evolution is subject to change due to random events.

If the direction is subjected to random change, then surely this is "random".


On to the statement about predictions:
(snip) Exactly! And, of course, all those examples you gave work against the idea of Evolution being purely random. The Creationists don't know what they're missing!


I think this is mostly an issue of semantics. I think that the interesting aspect is that the actual mechanism and implications. I would agree that evolution isn't "completely random", but I would argue that nor is it determined either.

I would argue that, in stable environments, the random mechanisms would tend to produce repeatable results (i.e. the stability of the environment provides a constant enough selective pressure). For these conditions I would argee that describing evolution as random, is unhelpful.

Over long timescales, with unstable environments, I would argue that the random element is important, as it will alter the direction of the selection pressures. This is important if one is discussing the evoultion of humanity, as the KT impact, the ice-ages, the cambrian extinction, Toba, etc could have altered the course of evolution so that intelligent hominids wouldn't evolve, maybe so that nothing occupied the ecological niche of complex-tool and fire using social animals.

[Wowbagger]

I, on the other hand, think that the way evolutionary biologists describe the process of evolution by natural selection as it occurs in the physical world is inherently stochastic (and not necessarily just because of out lack of knowledge of the details of the process) and that the existing data that we have corroborates this interpretation. How do you know? Stochastic implies that the system is ultimately deterministic, anyway. We just can't determine everything, because our knowledge is imperfect.

If you think the nature of Evolution is fundamentally stochastic, you are going to have to find a source or mechanism of indeterminism, in the system (other than quantum uncertainty, which is largely wiped out in the scales Evolution works in).

Until such a new source of "random" fluctuations are discovered, it seems best to think of Evolution as ultimately deterministic, so that we may continue making discoveries and formulating predictions with it.

You seem to have a very strong mathematical background, mijo. Perhaps your training is making you forget that science is based on evidential support, not what someone thinks.

There are non-chaotic physical systems where this isn't the case. The key word is "significantly". Ah, good to emphasize the key words.

I would argue that this means that the selection pressures, and thus the "direction" of evolution is subject to change due to random events.

If the direction is subjected to random change, then surely this is "random". It might be a matter of resolution. In the large scales Evolutionary models work in, such random events usually have a miniscule impact on the system, if any at all. The patterns of convergence we see is testimony to that.

Over long timescales, with unstable environments, I would argue that the random element is important, as it will alter the direction of the selection pressures. This is important if one is discussing the evoultion of humanity, as the KT impact, the ice-ages, the cambrian extinction, Toba, etc could have altered the course of evolution so that intelligent hominids wouldn't evolve, maybe so that nothing occupied the ecological niche of complex-tool and fire using social animals.But your examples (the KT impact, ice ages, etc.) were large enough events that any small changes in random fluctuation would not have stopped them from happening. In that sense, they are NOT random.
(Though, in another sense, you could use random to mean "unanticipated" by the life forms on the planet. But, such usage is probably not useful in describing the Evolutionary process.)

[jimbob]

Wowbagger,

I think we are emphasising slightly different things here. I also suspect that I have a lower "threshold of significance" than you, i.e. you are looking very broad-brush, whilst I am looking at the level of particular niches:

There are many pressures that are almost univeral and which act upon every member of say a kingdom, maybe even higher.

All animals will need to eat; they are unlikely to be able to afford to "waste" energy, so there will always be a pressure in favour of "frugality". Sometimes there are also opposing pressures, for example towards flight, however the ability to fly has a cost in energy, so should the need for flight vanish, the "frugality" pressure will act to reduce the ability to fly.

Is this the level of "significance" that you are talking about? (or indeed, the level of resolution that you are talking about).

At that resolution I would agree with you, however I am thinking about a *slightly* finer resolution.

Suppose our ancestors went through a stage of scavenging in the savannah, and in a slightly different universe, there was an animal that was a lot better at this than them, but that there was slightly less competition back in the trees. The surviving hominids could have ended up occupying similar niches to the chimps or bonobos, and not as ancestors to fire-using social animals.

An entire niche could remain unocupied/unavailable due to a slightly different set of competing organisms due to a different order of mutations altering the fitness landscape for other organisms.

This above example isn't terribly clear, I'm afraid, but I hope you can see what I am getting at.

[jimbob]

Maybe a clearer example would be to say that the rhino and triceretops seem to occupy/have occupied similar niches (ones that are highly likely to be filled). But I would argue that there are significant differences, and many of them are due to the randomness of the process.

[Walter Wayne]

Wowbagger,

Stochastic does not mean ultimately determistic.

Of course mijo is confusing the model with reality. The use of a stochastic model imples that the process is random or that it has hidden/unknown variables. So the use of the stochastic model doesn't tell us much about the randomness or lack of thesystem.

Walt

[mijopaalmc]

Since evolution is a process, I don't see how they could mean different things. But I'm willing to learn.

~~ Paul

I was thinking along the lines of the idea that bird dog doesn't mean a bird that is also a dog, or vice versa. In other words, maybe the phrase "random process" means something different than the sum of the words "random" and "process". I asked this question partially because "random process" has a exact and rigorous definition within probability theory and it therefore avoid the definitional problems that people insist on have with the single word "random".

[mijopaalmc]

I said it before and I'll say it again:

Variation is non-deterministic with respect to form.
Selection is deterministic with respect to form.

It does not matter ONE BIT whether or not that variation is caused by quantum mechanics, a die roll, a list of numbers, or even, horrors, a deterministic process, etc.. the important part is the deterministic relationships.

If variation is based on form then mutation is not the mechanism of change in form - previous forms are.

If selection is not based on form then what variations arise are inconsequential to what forms persist.

These are the basic and fundamental conditions that must be satisfied for any system that would be considered "evolutionary" - be it biological or a abstract model.

NOTA BENE deterministic with respect to is not the same as wholly determined by - yes mijo, I am thinking of you and your twins. Their form does not wholly dictate their selection but to argue that their selection is not deterministic with respect to it would be WRONG.

You are choosing to redefine the words "random" and "deterministic" to preclude evolution from being random, cyborg. In fact, you are ignoring that even if there were no bias in selection and no novel mutations introduced into the population that evolution would still occur purely by regression toward the mean. That is why you are wrong.

[Wowbagger]

I think we are emphasising slightly different things here. I also suspect that I have a lower "threshold of significance" than you, i.e. you are looking very broad-brush, whilst I am looking at the level of particular niches: The threshold is variable. And, yes, perhaps we are both right, but in different parts of the range.

Suppose our ancestors went through a stage of scavenging in the savannah, and in a slightly different universe, there was an animal that was a lot better at this than them, but that there was slightly less competition back in the trees. The surviving hominids could have ended up occupying similar niches to the chimps or bonobos, and not as ancestors to fire-using social animals. No need for DA tags, in that one. I would agree with it.

But, think about how much different the world would have needed to be, in order for that alternative scenario to take place. We are no longer talking about differences from mere randomness, there.

A bucket of water with one less drop in it, is still a bucket of water, in the end.

The flapping of a butterfly's wings may contribute to a hurricane, but would never, by themselves, generate one.

An entire niche could remain unocupied/unavailable due to a slightly different set of competing organisms due to a different order of mutations altering the fitness landscape for other organisms. It is possible, I suppose. But, I wonder: How often are slight differences really responsible for such things?

Can anyone offer examples where some slight difference clearly did make a huge impact on the course of evolution for some life form, that would not otherwise have occurred?

Maybe a clearer example would be to say that the rhino and triceretops seem to occupy/have occupied similar niches (ones that are highly likely to be filled). But I would argue that there are significant differences, and many of them are due to the randomness of the process. IIRC, Kangaroos and antelopes are another example of similar niches being filled by different-looking animals.

But, no matter what the details, we could still have predicted the niche would be filled.

Stochastic does not mean ultimately determistic. Well, perhaps, strictly speaking, yes. However...

The use of a stochastic model imples that the process is random or that it has hidden/unknown variables. So the use of the stochastic model doesn't tell us much about the randomness or lack of thesystem. ...for scientific purposes, it seems Occam's Razor would have determinism as the simplest explanation, unless evidence otherwise (with Heisenberg-like precision) is found.

If mijo thinks Evolution is fundamentally random, he has to deliver such evidence.

[mijopaalmc]

Congratulations, you managed to find merely the most commonly used definition of "random" (and probably the only definition of "random" used on those sites) and are now trying to pass it off as only definition in use in the English language.

So mijo, you really don't remember that long and excruciatingly annoying discussion we had in the "Evolution Not Random" thread about how your definition is useless, since according to it every single process in the world is random?

Strange, because here you are in a different thread more recently parroting almost verbatim what I was telling you there all along:

Except, to the best our knowledge, quantum mechanical events are random no matter how you try to constrain the variables. While it is mathematically true that a function of a random variable is itself a random variable*, it is not very useful in describing real world physical processes, because every actual physical process is based on quantum mechanics. However, it still important to make a distinction between non-chaotic deterministic systems (i.e., roughly systems in which small variations in initial conditions lead to small variations in final conditions) and chaotic deterministic systems (i.e., roughly systems in which small variations in initial conditions lead to large variations in final conditions). Evolution is most likely the latter because it takes place in a in an environment that is dependent on other chaotic systems (e.g., climate and weather). This means that exact predictions cannot be made about specific elements of adaptation, whereas predictions about the general course of adaptation can be made and are best handled in a probabilistic/statistical framework.

*meaning that random mutation based on probability leads to random evolution by natural selection regardless of whether natural selection itself is random or deterministic

I think you are misunderstanding what I wrote here. I was mainly responding to the fact that I had made the claim earlier in the thread that a function of a random variable (e.g., genomes after mutations) is a random variable, and evolution is therefore a random process because mutation is random. Consequently, I was saying that, even though this is incontrovertibly true from a mathematical standpoint, it is rather useless in describing physical systems if all our measurements are in fact random variables described by probability distributions.

The second part is a bit harder to understand because I seem to be describing a chaotic process in the way in which I would normally describe a stochastic process. However, my point was and still is, if our measurement are inherently imprecise and evolution by natural selection is indeed a chaotic system, it does us little good to think of it as a deterministic system (even though it is by definition deterministic), because (and this is part of the mathematical definition of a chaotic system) no matter how exact our measurements and how complete our knowledge of the systems are there will be some areas of the state space where a small differences in initial conditions are going to lead to large differences in final conditions. Therefore, it is much more practical and precise, due to the chaotic nature of the system, to derive a probability distribution for the possible values the measurements could assume.

[mijopaalmc]

Wowbagger-

How is assuming randomness less parsimonious that assuming determinism?

[Wowbagger]

How is assuming randomness less parsimonious that assuming determinism? Randomness lies outside of experimental science. A process that is truly random cannot be recreated in the laboratory, (at least not with any consistency).


ETA: Another, possibly more fitting, answer: The mechanism of randomness would have to be explained, and without evidence of its presence, should be disgarded. Natural determinism in a process needs no extraneous explanation.

[mijopaalmc]

Randomness lies outside of experimental science. A process that is truly random cannot be recreated in the laboratory, (at least not with any consistency).

You're missing the point yet again. Randomness can be tested in the lab (and in fact been tested to an absurdly high degree in the case of quantum mechanics).

ETA: Another, possibly more fitting, answer: The mechanism of randomness would have to be explained, and without evidence of its presence, should be disgarded. Natural determinism in a process needs no extraneous explanation.

Evidence of randomness's presence is identical initial conditions yielding different final conditions. This is how randomness is defined mathematically and scientifically. you are failing quite spectacularly at understanding this.

[Wowbagger]

Randomness can be tested in the lab (and in fact been tested to an absurdly high degree in the case of quantum mechanics). I agree with that. But, you have yet to show us such a source of randomness in the nature of Evolution, that can be tested in the lab.

Quantum mechanics has certainly been thoroughly tested, but its impact is largely erased at the large scales the process of Evolution works in.

Without evidence of a new source of randomness, it is better for the sake of scientific investigation, to assume one does not exist.

Evidence of randomness's presence is identical initial conditions yielding different final conditions. I would love to see some examples of this, in Evolution.

This is how randomness is defined mathematically and scientifically. you are failing quite spectacularly at understanding this. This topic is about how the word Random applies (or does not apply) to Evolution. How are those definitions relevant to Evolution, then?

I suspect that your mathematical training might be keeping you blind to the importance of evidential support.

[mijopaalmc]

Wowbagger-

Are you trying to tell me that natural selection neatly divides a population into two collections of phenotypes: one where no individual who possesses one of the constituent phenotypes has reproductively viable offspring and the other where every individual who possesses one of the constituent phenotypes has reproductively viable offspring?

That is what I hear when someone claims that evolution by natural selection is a deterministic process, and that is the kind of evidence that someone who claim that evolution by natural selection is a deterministic process.

By the way, I do understand that evolution by natural selection is non-random (i.e., deterministic) by the way that evolutionary biologist choose to define it, but I think evolutionary biologists' choosing to describe the actual process in this way is extremely inconsistent with the other ways in which evolutionary biologists use the concept of "random" within their own field.

[Taffer]

Wowbagger-

Are you trying to tell me that natural selection neatly divides a population into two collections of phenotypes: one where no individual who possesses one of the constituent phenotypes has reproductively viable offspring and the other where every individual who possesses one of the constituent phenotypes has reproductively viable offspring?

That is what I hear when someone claims that evolution by natural selection is a deterministic process, and that is the kind of evidence that someone who claim that evolution by natural selection is a deterministic process.

By the way, I do understand that evolution by natural selection is non-random (i.e., deterministic) by the way that evolutionary biologist choose to define it, but I think evolutionary biologists' choosing to describe the actual process in this way is extremely inconsistent with the other ways in which evolutionary biologists use the concept of "random" within their own field.

You keep saying what evolutionary biologists do and do not. Can you please elaborate on how these biologists use inconsistant definitions of random?

[mijopaalmc]

You keep saying what evolutionary biologists do and do not. Can you please elaborate on how these biologists use inconsistant definitions of random?

Again evolutionary biologists use an implicit understanding of randomness that is purely based in probability whenever the perform statistical hypothesis testing. This is especially true if they use parametric statistics, which require them to assume that population is described by a specific distribution (determined by the test they are performing) and test the sample data against that assumed distribution. It should not be hard to see how such a perception of randomness is inconsistent with any of the multitude of definitions that people have provide over the last 10 months.

[Taffer]

Again evolutionary biologists use an implicit understanding of randomness that is purely based in probability whenever the perform statistical hypothesis testing. This is especially true if they use parametric statistics, which require them to assume that population is described by a specific distribution (determined by the test they are performing) and test the sample data against that assumed distribution. It should not be hard to see how such a perception of randomness is inconsistent with any of the multitude of definitions that people have provide over the last 10 months.

Firstly, it's odd because a specific definition of "random" never came up when I was performing multitudes of population genetics and phylogenetics analyses. Secondly, what matters in these cases is what randomness causes, not what causes randomness. In other words, it doesn't matter if "random" means "acausal" or "deterministic but chaotic" or "goddidit". The tests work either way as long as the random null hypothesis is the same.

[Wowbagger]

Are you trying to tell me that natural selection neatly divides a population into two collections of phenotypes: one where no individual who possesses one of the constituent phenotypes has reproductively viable offspring and the other where every individual who possesses one of the constituent phenotypes has reproductively viable offspring? I am not sure I understand the question. But, I will do my best to address what it seems to be addressing:

First of all: the reproductive success of a phenotype depends on the fitness landscape. In some landscapes a phenotype will result in much better survival, in others it could instantly kill the life form. In most situations, it will probably lay anywhere in between. (Keep in mind that the life form's adapted survival strategies and evolutionary heritage are factored into this, as well.)

Second of all: I very much doubt natural selection neatly divides anything into two collections. Nature tends to abhor taxonomy. There will always tend to be gray areas between two extremes. (The appearance of neat categories is the fault of both human bias in perception, and the natural tendency for phase-shifts and clumping to occur in some of the data.)

That is what I hear when someone claims that evolution by natural selection is a deterministic process, and that is the kind of evidence that someone who claim that evolution by natural selection is a deterministic process. You probably heard incorrectly.

It is possible for nature to be both deterministic, and fail to neatly divide things into discrete categories.

It is humans who need to taxonomize, not nature.

By the way, I do understand that evolution by natural selection is non-random (i.e., deterministic) by the way that evolutionary biologist choose to define it, but I think evolutionary biologists' choosing to describe the actual process in this way is extremely inconsistent with the other ways in which evolutionary biologists use the concept of "random" within their own field.It might be true that the word "random" is not used consistently throughout the field. (That is why I have so many bullet points in the opening post.) Other words, such as "gene" and "species" are also inconsistently defined, in the field. However, it is important for the working usage to be consistent within the same study. As long as each individual study uses words consistently in themselves, this problem is manageable.

I would certainly like to see words used even more consistently, myself. But, there is little the two of us can do about it. Especially since science is in the business of altering its models. As the models improve, definitions get updated. Even if everyone now uses the words in exactly the same way, it will not stay that way forever.

[sol invictus]

I think you are misunderstanding what I wrote here. I was mainly responding to the fact that I had made the claim earlier in the thread that a function of a random variable (e.g., genomes after mutations) is a random variable, and evolution is therefore a random process because mutation is random. Consequently, I was saying that, even though this is incontrovertibly true from a mathematical standpoint, it is rather useless in describing physical systems if all our measurements are in fact random variables described by probability distributions.

The second part is a bit harder to understand because I seem to be describing a chaotic process in the way in which I would normally describe a stochastic process. However, my point was and still is, if our measurement are inherently imprecise and evolution by natural selection is indeed a chaotic system, it does us little good to think of it as a deterministic system (even though it is by definition deterministic), because (and this is part of the mathematical definition of a chaotic system) no matter how exact our measurements and how complete our knowledge of the systems are there will be some areas of the state space where a small differences in initial conditions are going to lead to large differences in final conditions. Therefore, it is much more practical and precise, due to the chaotic nature of the system, to derive a probability distribution for the possible values the measurements could assume.

It doesn't sound like I misunderstood you at all - what you just said in the quote above is what I spent quite a number of posts trying to explain to you in the previous thread. I'm glad I got through.

So it sounds like we agree - your definition of random is useless since it defines all physical processes as random, and hence the statment "evolution is random" is empty. More useful definitions exist (and in fact are the ones used by everyone but you), and according to most of those, evolution is not random.

[articulett]

'Just to weigh-in on this thread... I want to know if jim-bob, walter wayne, or mijo ever make sense or cede a point. I have a feeling that they'll be arguing that it makes sense to call evolution "random" as long as they are forum members... and I have my strong suspicions as to why. Jimbob has his own weird definition that he thinks is fabu (random mutation and probabilistic selection which is almost as empty as mijo's bizarre insistence at calling selection "random" because it can be described in terms of probabilities before the fact...) And I never could figure out Walter Wayne. I've ended up putting them all on ignore figuring that someone would quote them if they said something intelligible... but so far, I'm not seeing any intelligence or comprehension... just their same old insistence that it makes sense somehow to describe evolution in the same manner that Behe describes it no matter how misleading or empty such a definition is.

You have to admire their tenacity, however,-- in fact, it reminds me Behe.

Wowbagger and Sol Invictus... mark my words... you are having a discussion with people who have a vested interest in not understanding. No progress will be made. It's not you... it's not your explanations; it's them. These guys were saying the exact same nothingness over a year ago on Mijo's "evolution is not nonrandom" thread"... truly... nothing has changed. Nothing.

[Walter Wayne]

So it sounds like we agree - your definition of random is useless since it defines all physical processes as random, and hence the statment "evolution is random" is empty. More useful definitions exist (and in fact are the ones used by everyone but you), and according to most of those, evolution is not random.I agree with that mijo definition is useless, but I'm am wondering why you think by most other definitions evolution is not random, or at least which of those definitions would you think would not apply?

Walt

[sol invictus]

I agree with that mijo definition is useless, but I'm am wondering why you think by most other definitions evolution is not random, or at least which of those definitions would you think would not apply?


Here's a typical definition of random: "Lack of predictability, without any systematic pattern."

Something like that is what most people mean when they use the word. And that clearly does not apply to evolution - evolution is very predictable in many ways, and it follows patterns that we are quite capable of understanding. Of course its details are not predictable (which is the case for ALL OTHER physical processes too), but many broad patterns are - increase in complexity over time, survival of the fittest rather than the least fit, general characteristics of responses to changes in the environment, etc.

[mijopaalmc]

It doesn't sound like I misunderstood you at all - what you just said in the quote above is what I spent quite a number of posts trying to explain to you in the previous thread. I'm glad I got through.

So it sounds like we agree - your definition of random is useless since it defines all physical processes as random, and hence the