Why haven't other organisms evolved humanlike intelligence?

[enorbet]

There was a time several million years ago when there were several hominin species alive simultaneously. That is, until Homo sapiens sapiens killed them all off. Even today, we've just about driven all the great apes into extinction, and they're no threat to us at all. We need to be careful, because we'll never get that back.

I agree with much of what you have posted in this thread but I do take considerable objection to the sentence in Bold above. AFAIK there is no evidence that Homo sapiens killed off similar species and there is some evidence that cooperation was commonplace. Recent results from genome sequencing as well as archeological evidence support that Neanderthal and Sapiens lived alongside each other for thousands of years. I think this makes sense when one considers that in those early days in which Man was not exactly at the top of the food chain, safety in numbers had to be a powerful argument. It's not that I am offended by the "Murderous Ape" concept ( I am, but that is of no consequence ) since the reality is just as ugly in that Enslavement is much more likely. There is always a market for cheap.

Not in the biological sense, it is advantages (positive fitness) and disadvantages (negative fitness) and none (near neutral drift) that drives evolution over generations.

I did say "few generations". It is fairly common knowledge that Evolution is not goal driven and that what is an advantage under one set of conditions may actually be a disadvantage under others. Case in point - For hundreds of millions of years large size was a distinct advantage, at least in most environments. That all changed, a few times in fact, with catastrophic events like volcanos and impacts, but many studies suggest that substantial numbers of species were already "on the way" out from more subtle changes in environment.

What you drag in is the confounding between intelligence and survival that DiracPool identified above. 99.9+ of species goes extinct, and a mammalian species has an average survival time of a million years. So we are gone soon in any case.* But hominids are exceptions of wide diversity, long lifetimes (H. erectus ~ 2 million years) and success (half the mammal land biomass I think). That spells success due to advantages.

I don't see this as confounding but rather the most fundamental measuring stick. I don't see how any other measure other than numbers of years that what we can call a species has existed, can even remotely compete. In biological and evolutionary terms, the continuation of a species is success, right? The key to success, or at least the top contender, is adaptability, and while intelligence has been a key player in that for our species it hasn't always been the case.

In addition to the above references I made about the conflict between subconscious urges (very long term programming) and the effect of intelligence, especially through the medium of complex language bridging generations, there are also a large number of individual high level civilizations that have failed due to external events (drought and flood are majors) and also internal ones such as some people argue that lead pipe and lead eating and drinking utensils affect on such fantastic leaps in civilization such as found in Ancient Rome. In these cases it is sometimes lack of understanding what has made the world go mad, but it is also likely that doggedly sticking to "the old ways" played a part as well.

Not only do we embody internal conflict caused by unbalanced evolution (the above mentioned affect of language bridging generations vs/ the "merely" physical and long term programming) we also are capable of housing a great number of conflicts and contradictions in one body that somehow coexist somewhat comfortably. Although this does give us more options for adaptability, it also highlights how it is possible in both short term and long term, and in no way limited to just the cosmic roll of the dice of mass extinction events, for a single attribute to be both an advantage and a disadvantage.

That is wrong, I believe. They aren't the same biological species, and while it is hard to see that in the fossil record due to stasis of body plans (so sometimes taken as same fossil species) in some lineages it has become evident by genome sequencing.

*It used to be that Anatomically Modern Human was 0.2 Myr. But I believe the latest Pääbo et al result implies the evolutionary rates have been overestimated, and the species is perhaps twice as old. Unless we become as successful as Erectus, we are now entering old age as a species.

There is another thread on this forum asking the question "is our DNA the same as it was 20K years ago?" and of course it is not completely identical because Evolution continues. Similarly a great number of long living and long surviving species are changed some little bit over time just like us, but we would recognize a modern human from 20,000 years ago as human just as we recognize a horseshoe crab from 200,000,000 years ago for what it was. or sponges or yeast, etc.

Bottom line, by whatever standard you wish to employ, modern humans, even ancient progenitors, are newbies on the scene and it remains to be seen whether our version of intelligence is sufficient an advantage, or if the long term benefits outweigh both the disadvantages (there are a few) and our attributes not based in intelligence (response) vs/ instinct (reactions).

Like all here I revel in intelligence and am dismayed that underneath our tech achievements we are so few steps down from the trees and it seems less prominent in so much of our species (who are so resistant to change, so driven by ancient ways and instincts and therefore less adaptable) but to assume that our brand of intelligence is a key factor in what will carry us through, is not Science. Since we are so far apparently somewhat unique we have no frame of reference and are left with speculation.

That speculation is also a tangent to OP. That question is "Why?" not "whether or not". As has been noted a series of slow but powerful climatic events led to our evolving a combination of attributes, including intelligence, and such long term powerful events have not happened since. However we may be creating those conditions again, largely due to instincts that include competition over cooperation and insatiable greed, trumping brain power, but using it to further those urges. That said, even a dramatic climate change similar to the long term ones that fueled our progress along intelligence lines, is not guaranteed to repeat that performance, either in us, or in other species. Thus, it remains to be seen.

 

[Torbjorn_L]

the "Murderous Ape" concept

According to Pinker the violence has dropped historically. Today the murder rates, with a majority urbanized population where violence is perhaps twice the agrarian - is comparable to chimps. (There was a recent paper on that, so I compared the rates best I could.) Even bonobos can be comparably murderous, the statistics was both tentative and small, but the upper limit such as it was is about the same.

Chimps (and perhaps bonobos) may be the "Murderous Ape". I doubt humans, heavily self-socialized, is.

It is fairly common knowledge that Evolution is not goal driven and that what is an advantage under one set of conditions may actually be a disadvantage under others.

I didn't get that was your point in the previous comment. Still, we know that at least some of the tool set that we have evolved has lasted 2-3 million years (complex tool use).

I don't see this as confounding but rather the most fundamental measuring stick.

Then we have to agree to disagree. Intelligence is useful, but an evolution stopper it is not. If anything, the expanded population has made natural selection more effective (as measured in selective sweep rates) as it can pick up smaller fitness "signals" among random biological "noise".

just as we recognize a horseshoe crab from 200,000,000 years ago for what it was. or sponges or yeast, etc.

I was nitpicking on "species", and have to repeat: By a similarity or lineage description they would be horseshoe crabs, but our modern species they would not be.

That said, even a dramatic climate change similar to the long term ones that fueled our progress along intelligence lines, is not guaranteed to repeat that performance, either in us, or in other species. Thus, it remains to be seen.

My first comment on the thread went towards this. Rip out the bias of being first et cetera, and biologists would still say that it won't happen again, at least not in this biosphere. Meanwhile elsewhere, the astrobiologists have just seen (twice!) that planetary populations have a dual distribution, either 4-8 (which we belong to) or just 1 (or 0 for about half the stars). That implies an evolution from having an initial rich population to a last survivor.

In that sense our system is rare, it had a Jupiter/Saturn pair where Saturn was sufficiently massive to place Jupiter after the Jupiter-Saturn resonance of the Nice model. Add a rarity of complex life (took a while from oxygenation of the atmosphere until the mitochondrion event) and another rarity for language capable intelligence, and you will be pretty much alone in the galaxy at your specie's moment in time (~ 1 million years, presumably also in similar complex ecologies). I get ~ 10^3 concurrent civilizations, so ~ 3*10^-7/ly^3 (approximating the Milky Way as a (flat) cylinder) or ~ 100 ly to the next ETI at the optimistic end.

 

[David Carroll]

Because if there was an organism called Nikilapu, they would ask "Why haven't other organisms evolved Nikilapu-like intelligence?"

 

[enorbet]

According to Pinker the violence has dropped historically. Today the murder rates, with a majority urbanized population where violence is perhaps twice the agrarian - is comparable to chimps. (There was a recent paper on that, so I compared the rates best I could.) Even bonobos can be comparably murderous, the statistics was both tentative and small, but the upper limit such as it was is about the same.

Chimps (and perhaps bonobos) may be the "Murderous Ape". I doubt humans, heavily self-socialized, is.

I didn't get that was your point in the previous comment. Still, we know that at least some of the tool set that we have evolved has lasted 2-3 million years (complex tool use).

I'm not sure that you understand that I agree. I don't buy the "Murderous Ape" concept. AFAIK essentially all species are capable of murder, even bunnies and kitties and one-celled animals, certainly bacteria and virii :). I don't see that as a defining term, just a necessary attribute of survival for any lifeform

Then we have to agree to disagree. Intelligence is useful, but an evolution stopper it is not. If anything, the expanded population has made natural selection more effective (as measured in selective sweep rates) as it can pick up smaller fitness "signals" among random biological "noise".

I am utterly confused by this reply. I don't see any comment by anyone anywhere in this thread that contends that intelligence is an "evolution stopper". In my case, I stated exactly the opposite that "Evolution continues".

I was nitpicking on "species", and have to repeat: By a similarity or lineage description they would be horseshoe crabs, but our modern species they would not be.

Again I am somewhat confused. If I understand what you are saying as "horseshoe crabs won't become intelligent" I think that is exactly the point regarding the nature of evolutionary success and the assertion that intelligence is a major advantage across-the-board in evolutionary terms. Horseshoe crabs remain largely unchanged after at least 3 major mass extinction events. Are we able to trace what our ancestors were as of ~250 Ma?

My first comment on the thread went towards this. Rip out the bias of being first et cetera, and biologists would still say that it won't happen again, at least not in this biosphere. Meanwhile elsewhere, the astrobiologists have just seen (twice!) that planetary populations have a dual distribution, either 4-8 (which we belong to) or just 1 (or 0 for about half the stars). That implies an evolution from having an initial rich population to a last survivor.

In that sense our system is rare, it had a Jupiter/Saturn pair where Saturn was sufficiently massive to place Jupiter after the Jupiter-Saturn resonance of the Nice model. Add a rarity of complex life (took a while from oxygenation of the atmosphere until the mitochondrion event) and another rarity for language capable intelligence, and you will be pretty much alone in the galaxy at your specie's moment in time (~ 1 million years, presumably also in similar complex ecologies). I get ~ 10^3 concurrent civilizations, so ~ 3*10^-7/ly^3 (approximating the Milky Way as a (flat) cylinder) or ~ 100 ly to the next ETI at the optimistic end.

Agreed. I am aware that this is likely the best answer for the Fermi Paradox so far. I do however question the confidence that within a biosphere there will always be a "last survivor". Certainly more than a few times upwards of ~90% of all species have gone extinct, but much like the fact that humans have ~95% DNA in common with chimps confuses many people that don't understand how much room for variation is possible in that last 1-5% (not to mention the variation possible within the "similarity" of the other 95-99%) this rather ignores (or merely neglects to commonly state) the diversity of the survivors and the expansion obviously possible over eons. It may also ignore factors we have yet to comprehend. Again, it remains to be seen, and though it is illogical for me, who will be long dead, to care about the fate of Homo Sapiens, for some reason I do and I hope we beat the odds (as we now see them) and survive for ... oh... a billion years seems a nice round figure :)

 

[jim mcnamara]

Evolution has NO direction or intention nor does it have a pinnacle or a valley - it is simply an emergent process based on a simple set of "rules" imposed by physical laws. It is nothing more. Intelligence has evolved independently in Cephalopods, Cetaceans, Carnivora, and primates, for example. Ants of many species in some tropical environments constitute a majority of the biomass there. So using some of the ideas (not facts) tacitly expounded in this thread, they have "won". See: http://www.jstor.org/discover/10.2307/2989676?uid=3739816&uid=2&uid=4&uid=3739256&sid=21104928197017

There is no such thing as having "won" anything in evolution, just having survived to reproduce.

 

[Ryan_m_b]

The discussion seems to have naturally run its course and the OPs question addressed.