have they found anything?

[amb]

One day scientists may find the gene that causes us to age and die. But imagine the consequences for life on Earth if that was to ever happen? The planet is over populated already. In that case sending humans into space in search of other worlds to populate becomes imperative. I believe that may be the future. Life somehow started here on the Earth and is destined to populate the universe. I know the word ''destined'' has connotations of ID. But that's not necessarily so. We could become extinct within say, a century or two, and all this will never happen. There's your Fermi's Paradox.
The universe is just too big. We are alone as far as homo sapiens is concerned.

[Roboramma]

Originally Posted by davefoc

2. Even if limited interstellar space was possible I'm not sure that a civilization is going to put the resources into blasting a very few people into the great unknown for perhaps multiple generations.

I don't really see why it has to be people. Von neuman machines are all that we need. Well, Von Neuman machines that are also capable of producing something.

Quote:

3. Long term exposure to space radiation looks like it might be a difficult problem to solve.

I don't see why. The solution isn't to build a spaceship that's perfectly shielded from radiation: it's to build either robots or humans that can live with it. There are microbes that can sustain massive radiation without any problems, I don't see why building computers, robots, or people that could do the same is undoable. As long as technology continues to advance, it's inevitable that we'll learn how. (because there is a way: obviously if it were impossible we would never do so, but as I said: microbes already do it. All you need is good error checking, and during our evolution there was never any reason for it to be that good. In fact, if it were better than it is, it would have been selected against.)

Quote:

4. My guess is that at least some of amb's pessimism is well placed and the goldilocks type planets are uncommon and there just may not be one near enough to us to get to in even a few generations.

Yeah, I agree to that generally as well. However, I don't see why we need one. With advanced enough technology we might even prefer a few asteroids and comets to a "goldilocks planet".

Quote:

Still as I wrote this I was kind of amazed by all the things I don't know about the future and the unpredictable ways things might go. Maybe people end up with greatly lengthened lives and traveling through space for a few hundred years seems like an ok thing to do,

I don't really see how that's avoidable. I mean, there's no necessary barrier to how long we can live: it's just a matter of solving the problems. Of course, that may take us a very long time, but eventually we'll learn how our bodies work, learn to change them and fix them as need be.

Quote:

Maybe mass launchers turn out to be pretty easy to do and getting big chunks of stuff into space isn't that big a deal. Maybe the giant space based planet hunting telescopes get built and people learn enough about a target planet some place that finding a planet with conditions adequate for human life becomes possible.

Those would both be very cool.

Quote:

Or maybe we just kill ourselves before any of this stuff becomes possible in some massive nuclear exchange.

Very possible.

[LarianLeQuella]

I keep saying this, but no one seems to get this.

Who says that an alien intelligence would even have the drive or inclination to leave their planet? We are too focused on what WE humans would do if we could. Does that mean that other inteligences would behave even remotely like that? Maybe they just accept the death of their species when thier star is done, and don't care to leave anything. Us humans may be unique in our agression and wanting to leave a mark on the universe (There was a book called Birthright http://www.amazon.com/Birthright-Boo.../dp/1570900442 that may interest you. Just look at how humans are portrayed there.)

[amb]

That may well be the case if the aliens have reached a certain point of intelligence and progressed no further even after hundreds of centuries. If they reached a point like all the animals on Earth except for man. But if they developed consciousness like us, I'm certain their curiosity would get the better of them enough to search for other intelligences.
Take man away from the equation as far as the Earth is concerned. Would the rest of life on this planet give a hoot, or know when the sun has reached the end of it's life?

[JoeTheJuggler]

Originally Posted by amb

That may well be the case if the aliens have reached a certain point of intelligence and progressed no further even after hundreds of centuries. If they reached a point like all the animals on Earth except for man. But if they developed consciousness like us, I'm certain their curiosity would get the better of them enough to search for other intelligences.

Again, your assumption is that humans are the only species to have "developed consciousness" on the Earth. That assumption is false. The human brain didn't spring into being out of nothingness. That's not how evolution works.

Now, as for your notion that all conscious minds exhibit human-like curiosity--what do you base this certainty on?

Quote:

Take man away from the equation as far as the Earth is concerned. Would the rest of life on this planet give a hoot, or know when the sun has reached the end of it's [sic] life?

You're mixing two different questions here, I think. First you're asking whether any other animal on the Earth might possibly develop the intelligence and technology to figure out that the Sun will someday "die". Yes, that's possible.

Second, you seem to be asking a question whether any other animal on Earth can consider its own mortality. That might be the case even now. It's definitely possible for the future. (We know it's possible, because it happened with us. Unless you consider humans to be some special act of creation, there is no reason why the evolution of these characters that has happened once is impossible to happen again.)

[Dragoonster]

Originally Posted by JoeTheJuggler

Travelling to another planet is very unlike our ancestors of 500 or so years ago crossing the Atlantic. They did not have to carry along every bit of oxygen, food and fuel they would need.

While it may be a fallacy, if the human race survives another million/billion years, we'll have technology we can hardly fathom today. Towards needing to carry things, energy is abundant in the Universe, just needs collection or unlocking. And we're already fabricating things. I could certainly see a machine that would collect ambient energy, or use nuclear/nuclear-type power to fabricate oxygen, food, and fuel for however long it took. As well as fabricating a new fabricator.

Thinking about intelligent aliens and colonizing space isn't a wasteful pursuit, but it's far too soon to draw conclusions about any of it.

[davefoc]

Originally Posted by LarianLeQuella

I keep saying this, but no one seems to get this.

Who says that an alien intelligence would even have the drive or inclination to leave their planet? We are too focused on what WE humans would do if we could. ...

My apologies, I hadn't noticed you saying that even once. It's a long thread that has been going on for awhile and I'm old (kind of) and maybe I just forgot that you said it.

I don't think anyone said that an alien would necessarily think like a human. We know of a single example of an organism with an intelligence level that might be capable of creating a mechanism for interstellar flight to judge what an alien might be like. A reasonable extrapolation is that an alien entity with a similar capability might have similar motivations to humans and it might not. I don't think anybody that has participated in this thread would disagree with that.

So among the many reasons that there might not be alien entities zipping around earth these days is that the aliens who might be capable of doing it just don't feel like it.

[amb]

Originally Posted by JoeTheJuggler

Again, your assumption is that humans are the only species to have "developed consciousness" on the Earth. That assumption is false. The human brain didn't spring into being out of nothingness. That's not how evolution works.

Now, as for your notion that all conscious minds exhibit human-like curiosity--what do you base this certainty on?


You're mixing two different questions here, I think. First you're asking whether any other animal on the Earth might possibly develop the intelligence and technology to figure out that the Sun will someday "die". Yes, that's possible.

Second, you seem to be asking a question whether any other animal on Earth can consider its own mortality. That might be the case even now. It's definitely possible for the future. (We know it's possible, because it happened with us. Unless you consider humans to be some special act of creation, there is no reason why the evolution of these characters that has happened once is impossible to happen again.)

Not an act of special creation. Just a very unlikely event that may not happen as often as Drakes equation speculates.

[davefoc]

Originally Posted by amb

Not an act of special creation. Just a very unlikely event that may not happen as often as Drakes equation speculates.

It seems like quite a bit of this thread has dealt with nit picking about some of the things you've said amb.

Your last post has inspired me to do a bit of nit picking myself:

I don't think the Drake equation itself produces any estimate unless values are supplied for the various parameters. So the Drake equation itself can produce an estimate ranging from almost non-existent to common depending on what values are assigned to the various parameters.

It might be what you meant is that the parameters that Drake favors for his equation produce an estimate of intelligent life capable of interstellar communication in our galaxy that is higher than what you believe is likely.

I am weak on the actual numerical details but after having read what Drake said about this recently, I think I agree. Drake thinks that the probability of intelligent life capable of interstellar life are higher than he previously thought because of the recent discoveries of planets outside our solar system and new ideas that intelligent life might exist in a wider range of habitats than we had imagined.

My gut feel about this is that he is wrong and that the band where intelligent life can exist in a solar system is narrow and the band where intelligent life can exist in the galaxy is narrow and the lifetime of technologically sophisticated civilizations is small so I suspect that there aren't very many civilizations in the galaxy at any one time capable of interstellar communication.

[JoeTheJuggler]

Originally Posted by davefoc

It seems like quite a bit of this thread has dealt with nit picking about some of the things you've said amb.

I respectfully disagree. Amb has repeatedly said that humans are the only species on the Earth to have evolved intelligence. It's factually wrong, and it smacks of creationism in considering humans to be unique (even if the evolution of intelligence is low probability--and it might not be as theories of convergent evolution predicts--it is not impossible to happen again given enough chances). This is not nit picking because it points to a severe misunderstanding of biology.

Quote:

I don't think the Drake equation itself produces any estimate unless values are supplied for the various parameters. So the Drake equation itself can produce an estimate ranging from almost non-existent to common depending on what values are assigned to the various parameters.

That's a point I was trying to make early in this thread. The value of the Drake equation is to tell us what information we would need to answer the question of how probable intelligent civilization is (or how many there might be). Since most of the values are unknown, it does not claim to have an answer.

Amb has several times asserted conclusions of the probability of ETIs in the galaxy.

Quote:

I am weak on the actual numerical details but after having read what Drake said about this recently, I think I agree. Drake thinks that the probability of intelligent life capable of interstellar life are higher than he previously thought because of the recent discoveries of planets outside our solar system and new ideas that intelligent life might exist in a wider range of habitats than we had imagined.

My gut feel about this is that he is wrong and that the band where intelligent life can exist in a solar system is narrow and the band where intelligent life can exist in the galaxy is narrow and the lifetime of technologically sophisticated civilizations is small so I suspect that there aren't very many civilizations in the galaxy at any one time capable of interstellar communication.

I can't pass up the opportunity to repeat a bit of the Sagan quote: "But I don't like to think with my gut."

I think the point Drake makes is that his equation prematurely rules out other situations for life (like interstellar planets, maybe twilight zone on planets orbiting Red Giants, and maybe something else we haven't even thought of yet). Maybe he thinks that the equation would yield a value that is erroneously low, but at the least the observation that the equation wrongly limits the question is true. We don't know that life (or intelligent life) can't exist in these other situations.

I think we should have more than one Drake equation. I would like one that doesn't connect the issue of the existence of intelligent life with the probability of us (or any two) communicating. To me that's a different enough question from the question of "Are we unique?" to warrant separate consideration.

[davefoc]

Originally Posted by JoeTheJuggler

I think we should have more than one Drake equation. I would like one that doesn't connect the issue of the existence of intelligent life with the probability of us (or any two) communicating. To me that's a different enough question from the question of "Are we unique?" to warrant separate consideration.

Until I was thinking about my post above, I hadn't noticed that the Drake equation produces a result that is easily mischaracterized. The product of the Drake equation factors as I now understand it is the number of planets in the galaxy with inhabitants that have the capability for interstellar communication at any one time. It is not the number of civilizations in the galaxy that might be capable of communicating with Earth.

So perhaps the second Drake equation would include a factor that represented the ratio of the stars in the universe that Earth might be able to communicate with to all the stars in the galaxy. Maybe we could call that the Drake contact chance equation.

My rough guess is that the Drake equation equals a number somewhat greater than one, my less rough guess is that the number of civilizations in the galaxy that might be able to communicate with Earth is zero.

[amb]

Originally Posted by davefoc

It seems like quite a bit of this thread has dealt with nit picking about some of the things you've said amb.

Your last post has inspired me to do a bit of nit picking myself:

I don't think the Drake equation itself produces any estimate unless values are supplied for the various parameters. So the Drake equation itself can produce an estimate ranging from almost non-existent to common depending on what values are assigned to the various parameters.

It might be what you meant is that the parameters that Drake favors for his equation produce an estimate of intelligent life capable of interstellar communication in our galaxy that is higher than what you believe is likely.

I am weak on the actual numerical details but after having read what Drake said about this recently, I think I agree. Drake thinks that the probability of intelligent life capable of interstellar life are higher than he previously thought because of the recent discoveries of planets outside our solar system and new ideas that intelligent life might exist in a wider range of habitats than we had imagined.

My gut feel about this is that he is wrong and that the band where intelligent life can exist in a solar system is narrow and the band where intelligent life can exist in the galaxy is narrow and the lifetime of technologically sophisticated civilizations is small so I suspect that there aren't very many civilizations in the galaxy at any one time capable of interstellar communication.

But that's been my argument from day zero. The Goldilocks argument as well.
Also, just today I was reading an astronomy book which stated that the arm of the galaxy the earth is part of orbits the center of the galaxy every 250 million years. Who's to say that in future this orbit doesn't take us within a nearby recent supernova. It would mean the complete sterilization of the earth. The time period of an intelligent species may indeed be very short in astronomical terms.

[LarianLeQuella]

Another consideration to put in here. There are organisms on this planet that only reproduce once every thousand years or so. Maybe us humans and this planet has produced a flash in the pan type of ecology? Just idle speculation.

And the reason we "pick" on AMB is that he says things so absolutely that are either outright wrong, or that we have no basis to assert such a statement. We're really just trying to help.

And yeah, the "human-centric" statements were made quite a while ago in this thread davefoc. I keep addressing them mostly to AMB though, so no worries.

[JoeTheJuggler]

Originally Posted by davefoc

So perhaps the second Drake equation would include a factor that represented the ratio of the stars in the universe that Earth might be able to communicate with to all the stars in the galaxy. Maybe we could call that the Drake contact chance equation.

And that's an equation that could yield a zero.

I also think a shorter version of the equation (one that stops before f_c and L) which would yield the total number of intelligent civilizations there have been throughout the galaxy ("throughout" in space and time). This is the probability that amb speaks of. At one time he said it's most likely humans are the only intelligence ever to arise in the galaxy (and that it was highly unlikely that are more than a dozen in the entire universe). I'm not so pessimistic. I think the number is likely to be much higher, though stuff is still so spread out in space and time that we're not likely ever to encounter another intelligent civilization.

[JoeTheJuggler]

Originally Posted by amb

Also, just today I was reading an astronomy book which stated that the arm of the galaxy the earth is part of orbits the center of the galaxy every 250 million years. Who's to say that in future this orbit doesn't take us within a nearby recent supernova. It would mean the complete sterilization of the earth. The time period of an intelligent species may indeed be very short in astronomical terms.

You mean an extra-galactic recent supernova? I'm not sure I follow what you're even talking about.

Maybe you don't understand how the arm of our galaxy is more or less held together by gravity? A supernova (indeed all the stars that compose the arm) move with the arm. (ETA: I realize that the stars that compose our arm of the galaxy do individually have real motion relative to one another, but that's not the same as the rotation of the galaxy.)

At any rate, there are any number of events that could happen in the timespan of 250 million years that could push the ecological "reset" button on the Earth. I don't think there are many such events that could actually wipe out all life though. (Life exists in plenty of places in the Earth that are well shielded from an x-ray or gamma ray burst --or whatever--from a relatively near supernova.)

ETA: Your broader point--that the span of intelligent life could be relatively brief is in fact one of the points I made in my numbered list of points refuting your argument based on Fermi's Paradox. (That is, the absence of evidence of ETIs does not prove the non-existence of ETIs. Fermi's Paradox requires or assumes that spacefaring civilizations necessarily persist for a long time.)

[amb]

So perhaps I need to change my thinking into, that truly we as homo sapiens are alone. That any other civilization my find this planet when it's completely sterile as far as 'us' is concerned, when we have well and truly long been extinct. That two or more civilizations are an impossibility to exist at the same time within say 10-20 light years.

[JoeTheJuggler]

Originally Posted by amb

So perhaps I need to change my thinking into, that truly we as homo sapiens are alone. That any other civilization my find this planet when it's completely sterile as far as 'us' is concerned, when we have well and truly long been extinct. That two or more civilizations are an impossibility to exist at the same time within say 10-20 light years.

That doesn't sound like a change in your thinking at all. You are still claiming something is impossible that is clearly possible, even if not very likely.

Similarly, you claimed it was not possible for another species on Earth to evolve human-like intelligence.

[amb]

Originally Posted by JoeTheJuggler

That doesn't sound like a change in your thinking at all. You are still claiming something is impossible that is clearly possible, even if not very likely.

Similarly, you claimed it was not possible for another species on Earth to evolve human-like intelligence.

Well no other species has done so and we have been here a hell of a long time. And it appears that it's not about to happen either.
Why do you believe that if sapiens were to become extinct, the nearest relative to him will take over the civilization duties?
No other primate has shown any inclination to do so, or for that matter, any marine life. Yes they have shown 'some' intelligence. But to gather from that they any would replace us is drawing an extreme long bow.

[JoeTheJuggler]

Originally Posted by amb

Well no other species has done so and we have been here a hell of a long time. And it appears that it's not about to happen either.
Why do you believe that if sapiens were to become extinct, the nearest relative to him will take over the civilization duties?

Sigh. Nice try, but you know full well by now that I'm not claiming that any other animal would "take over the civilization duties" (whatever that means).

You are wrong when you claim that it is impossible for human-like intelligence to evolve in any other species.

Quote:

No other primate has shown any inclination to do so, or for that matter, any marine life. Yes they have shown 'some' intelligence. But to gather from that they any would replace us is drawing an extreme long bow.

Again, if humans went extinct (and somehow magically left all other living species alive), then immediately another species would be the most intelligent animal.

I'm not sure what you mean by "replace" us, but I do think the ecological niche we vacated would be filled by other animals. (Again, with the caveat that I don't see this hypothetical ever happening where Homo sapiens goes extinct but chimpanzees do not. In fact, I think the reverse is much more likely to happen in the real world where there are nearly 7 billion of us and just a couple hundred thousand of them at the most.)

If the Giraffa camelopardalis species went extinct tomorrow, some other animal would then become the tallest animal in the world (and some other animal would be the new largest ruminant), and it would be wrong to claim that "giraffe-like" height would be impossible ever to evolved again in another species.

[LarianLeQuella]

Did anyone watch "Becoming Human" last night on Nova? One thing that struck me as being pertinent to this discussion:

Apparently the rapid changes in environment in the rift valley region was a significant contributing factor to the development of our intelligence. In other words, my counter argument to the rare earth hypothesis, it may seem that the moon and our stable rotation and protection from meteor impacts may actually have impeded the evolution of intelligence on this planet...

Just saying.

[amb]

Originally Posted by JoeTheJuggler

Sigh. Nice try, but you know full well by now that I'm not claiming that any other animal would "take over the civilization duties" (whatever that means).

You are wrong when you claim that it is impossible for human-like intelligence to evolve in any other species.



Again, if humans went extinct (and somehow magically left all other living species alive), then immediately another species would be the most intelligent animal.

I'm not sure what you mean by "replace" us, but I do think the ecological niche we vacated would be filled by other animals. (Again, with the caveat that I don't see this hypothetical ever happening where Homo sapiens goes extinct but chimpanzees do not. In fact, I think the reverse is much more likely to happen in the real world where there are nearly 7 billion of us and just a couple hundred thousand of them at the most.)

If the Giraffa camelopardalis species went extinct tomorrow, some other animal would then become the tallest animal in the world (and some other animal would be the new largest ruminant), and it would be wrong to claim that "giraffe-like" height would be impossible ever to evolved again in another species.

But you have just agreed with me without realizing it.
If we 'magically' were to become extinct, it would mean the end of civilization. Sure all other animals, or the next intelligent creature down from us would take over as the next more smarter species, but it's not capable of building a satellite, computer etc.

[amb]

Originally Posted by LarianLeQuella

Did anyone watch "Becoming Human" last night on Nova? One thing that struck me as being pertinent to this discussion:

Apparently the rapid changes in environment in the rift valley region was a significant contributing factor to the development of our intelligence. In other words, my counter argument to the rare earth hypothesis, it may seem that the moon and our stable rotation and protection from meteor impacts may actually have impeded the evolution of intelligence on this planet...

Just saying.

That's arguable. If the asteroid that wiped out the dinosaurs had not struck the Earth when it did, perhaps they would still be around in some form. I know that birds are the descendants, but perhaps they would still be gigantic in size and impeded homo sapiens from evolving.

[JoeTheJuggler]

Originally Posted by amb

That's arguable. If the asteroid that wiped out the dinosaurs had not struck the Earth when it did, perhaps they would still be around in some form. I know that birds are the descendants, but perhaps they would still be gigantic in size and impeded homo sapiens from evolving.

Or it could be that if an asteroid had struck a million or ten years earlier that humans might have evolved sooner.

This is the point I raised when I first gave a summary of Darling's book. The Rare Earth hypothesis basically says that for complex life to evolve, every little thing about the Earth must be in place and regarded as friendly to life. At the same time, it seems that trauma is what drives big changes in evolution. (The Cambrian explosion can be seen as the result of the poisoning of the atmosphere with too much oxygen pollution.) It's basically the idea of punctuated equilibrium.

As I've said before, we don't know that hitting the ecological "reset" button more frequently might not result in more complex forms (including greater intelligence) arising sooner. The Earth might be too friendly for that, and what took billions of years here might happen more quickly elsewhere. (I'm not asserting it's so, only that it's just as valid to speculate this as to make the speculations made in the Rare Earth hypothesis.)

[JoeTheJuggler]

Originally Posted by amb

But you have just agreed with me without realizing it.
If we 'magically' were to become extinct, it would mean the end of civilization. Sure all other animals, or the next intelligent creature down from us would take over as the next more smarter species, but it's not capable of building a satellite, computer etc.

Yes, I agree that if human civlization were wiped out it would be the end of human civilization. But that's just a trivial observation.

I disagree with you that it would be impossible for another intelligent civilization to develop ever again, which is what you've asserted several times.

[amb]

We only have one example to study, and that example has shown that only one species out of literally billions of life forms that have ever lived here on this one example have had the intelligence enough to produce a civilization. And this going over old ground.
Also, extinction seems to be the norm/rule. Survival is the exception. We may not survive until the time it takes to develop interstellar craft that can reach at least 10% of the speed of light. It seems that traveling to another star system is just a pipe dream unless we can survive at least another 100.000 years intact. This is why I suspect we haven't been visited yet by a much older alien civilization. A technological civilization usually blow themselves up before they achieve interstellar travel. Or perhaps their world is struck by a huge asteroid ending all complex life as our will be one day.

[Roboramma]

amb, if the blue whale went extinct, would it be impossible for a larger animal to evolve in the future?

[JoeTheJuggler]

Originally Posted by amb

We only have one example to study, and that example has shown that only one species out of literally billions of life forms that have ever lived here on this one example have had the intelligence enough to produce a civilization. And this going over old ground.

How exactly do you define civilization? How do you know only one species has ever had intelligence enough to produce one?

Yes, this is going over old ground.

And since you're repeating yourself, I'll repeat that intelligence is not unique to humans and exists (and has existed) as a continuum among many species on Earth.

Also, if you mean to change Earth from a 1 for 1 data point to a 1 for a few billion (in say technology capable of sending and receiving radio signals) that's fine, but it doesn't help your case that intelligent life in the galaxy is necessarily limited to us. In other words, if you count Earth as 1: 3 billion, then you have to treat the same ratio in the galaxy as

number of human-like intelligent species in the galaxy: the total number of species (rather than life-bearing planets) in the galaxy

It doesn't help your argument to make the second value greater.

[JoeTheJuggler]

Originally Posted by amb

We may not survive until the time it takes to develop interstellar craft that can reach at least 10% of the speed of light. It seems that traveling to another star system is just a pipe dream unless we can survive at least another 100.000 years intact. This is why I suspect we haven't been visited yet by a much older alien civilization. A technological civilization usually blow themselves up before they achieve interstellar travel. Or perhaps their world is struck by a huge asteroid ending all complex life as our will be one day.

Funny, those sound exactly like some of the the points I listed by number to refute your argument based on Fermi's Paradox.

Since we can't expect evidence of an intelligent civilization to be ubiquitous in the galaxy, the lack of that evidence doesn't argue that such civilizations don't exist.

Or, as I said very early, it could be that there could be hundreds or thousands of radio-technology-using intelligent civilizations in the galaxy but since things are so spread out in space and time we may still never run across them.

I agree that this is probably the reason why we haven't been visited by another civilization rather than the conclusion given by the Rare Earth hypothesis that we are so rare as to be certainly unique in the galaxy.

[amb]

Originally Posted by Roboramma

amb, if the blue whale went extinct, would it be impossible for a larger animal to evolve in the future?

The blue whale has been here for millions of years. It has come close to been made extinct by man's greed. But no. To your question. If you think otherwise, which of the present marine creatures do you think could take it's place, even given another million years.

[Roboramma]

Originally Posted by amb

The blue whale has been here for millions of years. It has come close to been made extinct by man's greed. But no. To your question. If you think otherwise, which of the present marine creatures do you think could take it's place, even given another million years.

Any of the baleen whales could evolve to fill the same niche. You will note that I said could, and of course it may take more than a million years, it may take tens of millions of years.

It may be a penguin that turns out to evolve to a life completely in the water, and much larger even than the blue whale.

The whale shark is a pretty big fish which, unless I'm mistaken, also fills a similar niche to the blue whale. Similar pressures could cause it to evolve to be bigger as well.

Of course, it's possible that if the blue whale goes extinct, nothing will ever evolve to be larger than it. But there's also nothing stopping it from happening, and there are certainly selection pressures toward larger size, so it's not particularly unlikely that it could happen in the future.

I actually hadn't even imagined that you would make that answer, it's just so incomprehensible to me that someone could think it's impossible for something which already happened to happen again.

[amb]

Do you ever consider the tape of Earths history been re-played again from day zero.
And if you did, do you understand the trillion to one chance that homo sapiens would evolve to be exactly the same as we are today? That goes for every form of life that's ever lived on this planet, none would be the same again. We would not recognize it if we were to be a spectator.

Happy birthday. May you have many, many more.

[LarianLeQuella]

Originally Posted by amb

Do you ever consider the tape of Earths history been re-played again from day zero.

STOP WITH THAT FARKING RED HERRING!!!!!!!!!!

Seriously dude, that is the downright most assenine and even stupid argument I have ever hear presented by anyone who would even consider Sagan a person of note, let alone a here of any sort (which you have said). That is not in the slightest at all, or even remotely what we are saying. You keep bringing this up, and all we can coclude is that you have absolutely zero understanding of evolution, and what it is we are trying to say. That stupid statement makes me want to apply a car battery to your genitalia and shock you ever time you write it. Seriosuly, stop it!

[JoeTheJuggler]

Originally Posted by amb

Do you ever consider the tape of Earths history been re-played again from day zero.
And if you did, do you understand the trillion to one chance that homo sapiens would evolve to be exactly the same as we are today? That goes for every form of life that's ever lived on this planet, none would be the same again. We would not recognize it if we were to be a spectator.

Yeah, this is getting old, amb. I've already told you that the search for ETIs is not the search for ET Homo sapiens. Nobody thinks it's likely that we'll find a species identical to Homo sapiens "out there". Or that the evolution of Homo sapiens was pre-ordained somehow.

Now, the odds of life intelligent life evolving if you re-ran the history of Earth? Or the probability of an ET intelligent civilization? Who knows?

Those who think convergence explains a lot of evolution would say it might be inevitable, or very nearly so.

Of course the fact is we don't know, and where most of us disagree with you is in your claim to know (that is your claim that another species evolving human-like intelligence is impossible).

[JoeTheJuggler]

Originally Posted by Roboramma

I actually hadn't even imagined that you would make that answer, it's just so incomprehensible to me that someone could think it's impossible for something which already happened to happen again.

And that is the central point he is making about ETIs. That even though it happened here on Earth, he insists that it's impossible to happen elsewhere.

[JoeTheJuggler]

Originally Posted by amb

The blue whale has been here for millions of years. It has come close to been made extinct by man's greed. But no. To your question. If you think otherwise, which of the present marine creatures do you think could take it's [sic] place, even given another million years.

I'll answer your question if you'll answer mine.

My answer to your question: any species can evolve to be the size of the blue whale given enough time.

Why do you think it is impossible for any species to evolve to this size?

[dallasroofer]

I suppose we could debate this all day long. To quote the great Carl Sagan:

"But the fact that some geniuses were laughed at does not imply that all who are laughed at are geniuses. They laughed at Columbus, they laughed at Fulton, they laughed at the Wright Brothers. But they also laughed at Bozo the Clown."

But I say, who's to say (including Sagan) that Sagan wasn't a genius as well. Like Achilles he will be remembered.

[dallasroofer]

I define it by using things like money, language, and the creation of the arts & humanities. I would also single out morality as a not entirely unique trait of human civilization, but we care more about morality than say a snow leapord eating an impala.

[Roboramma]

For amb:

http://en.wikipedia.org/wiki/List_of...gent_evolution

[amb]

Happy birthday Carl Sagan. He would have been 75 today. We lost a genius much to early.

RIP.

Roboramma, I know all that.

[Roboramma]

Originally Posted by amb

Roboramma, I know all that.

Okay, so...

If you understand convergent evolution, and the fact that the same traits evolve multiple times in completely separate lineages then what, again, was it that makes you think it's impossible for the same trait to evolve multiple times?