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Why haven't other organisms evolved humanlike intelligence?

  1. Jul 15, 2014 #1
    It seems like it would be a huge advantage to their survival, so why haven't other organisms evolved such? Why are humans the only organisms capable of doing things like creating complex technology and using complex language?
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  3. Jul 15, 2014 #2

    jim mcnamara

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    This is an anthropomorphic answer, based on a text on a similar subject, given the question seems to be one as well: How would most humans react to some fuzzy mammal that seemed to be intelligent, reacted defensively and became murderously aggressive in groups when it seemed it would be able to "win" a conflict due to superior numbers.

    (Hint: they would go out of their way kill one anytime they saw one. )

    Replace "fuzzy mammal" with human and you essentially are describing part of human tribal behavior. Humans have been in the situation of fighting for territory and resources for a very long time.

    Since we got tools and language first do you really think early men would have put up with competing species?

    Jared Diamond discusses this concept with good stories and provides detailed insight in 'The World Until Yesterday':


    Good book - worth a serious read.

    Short answer: Humans already occupy the niche for supreme predator, and dominant mammal on all inhabited continents. Any non-human species acting as contenders for the niche would lose. This is the same reason why there are not hundreds of different large carnivorous species all living in one biome. The few species that already have a foothold are really hard to out-compete, without a disastrous environmental change to level the playing field.
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  4. Jul 15, 2014 #3
    Intelligence seems to be of limited advantage in survival. True there are niche applications, but the vast majority of successful organisms have very limited intelligence.

    The fact that humans are the first species to evolve on this planet with such an "advanced" intelligence in three and a half billion years suggests that there are many more ways to become successful than be intelligent. The next century or so will show if intelligence is actually all that effective for long term survival.
  5. Jul 16, 2014 #4
    Humans not as "advanced" as chimps in short-term memory ...
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  6. Jul 16, 2014 #5
    Someone had to be first - and we may have killed off competitors.

    Intelligence isn't worth much unless it is shared. A whole bunch of genius alligators that never talk to one another wouldn't advance their species a whole lot in terms of survival.

    So the only animals that are candidates would be social ones.
  7. Jul 16, 2014 #6
    Are you serious?

    By "niche applications" do you mean the domination of the planet, the ability to control and domesticate virtually all of plant and animal life, the redirection of geological structures to create dams, etc., and the exploration of space... among many others?

    You are correct in saying that the vast majority of successful organisms have very limited intelligence, at least in relation to the type of intelligence humans have. However, their success does not rest on the fact that they are "stupid." The success of a given species can result from several different reasons unrelated to "intelligence" per se, 1) lack of natural predators in their particular niche, 2) lack of species competing for resources, 3) an excessively high reproduction rate, and many others. Most of the "dumb" species that have been around for many millions of years have more that anything "lucked out" to have settled into such niches, or have had the reproductive capacity to spread out fast enough to stay one step ahead of the grim reaper or just simply evolve into something else. Being dumb doesn't help you survive. I think you would be hard pressed to find many evolutionary biologists that would agree that stupidity is a trait that is survivally advantageous. It is the clever squirrel that survives and reproduces, not the stupid one, and it is the EARLY bird that actually does get the worm, not the one that sleeps in (like me:redface:)

    Well, that certainly is a true statement. If we do blow ourselves up or trash the environment so bad it leads to our demise as a species, which is certainly possible, you may just indeed have the last laugh.
  8. Jul 16, 2014 #7
    Yes. Give my cat a humanlike intelligence. What would she be able to do with it. She has no physical capabilities of building anyting complex or using any tools. Furthermore, such an intelligence takes up a lot of energy (our brain takes up over 20% of all our energy). So I wouldn't exactly call it very beneficial. It's only beneficial if certain other side conditions are satisfied.

    Whales are said to be quite intelligent. I don't think that really helps them. They have no capabilities to do much with said intelligence.
  9. Jul 16, 2014 #8
    What does building anything complex or using any tools have to do with anything? Your response of "yes" was to the quote of Ophiolite, "Intelligence seems to be of limited advantage in survival."

    So by that argument, Stephen Hawking's intellect is of limited advantage in survival. Stephen Hawking isn't building anything complex or using any tools, and I'm sure he has much less physical capacity than a cat. Even so, he's a celebrity, and has teams of doctors keeping him alive and teams of fans feeding him, wheeling him around to conferences, and putting his ideas up for him on the blackboard.. So I'd say his intelligence has a great advantage in his survival.

    Again, by that argument you're essentially saying that the strain on natural resources of a few extra plates of pasta a week wasn't worth powering Einsteins brain to come up with the General theory of relativity, or a few extra calories in Hawking's liquid diet wasn't worth the equation of black hole entropy.

    Side conditions like what?

    Chimpanzees are also said to be intelligent, as well as a host of other animals such dolphins, monkeys, elephants, even birds such as the African grey parrot and Magpie. It all depends on who you ask and what their criterion is for "intelligence." Human-like intelligence is very specific, it is the ability to hierarchically construct temporally extended symbol assemblies in an essentially unlimited fashion. Nonhuman animals simply do not have this capacity, which is why, as the OP queried, "humans the only organisms capable of doing things like creating complex technology and using complex language?"

    As far as the whales are concerned, they've done just fine with whatever intelligence they had, that is at least until the super-intelligent greedy humans came along.
  10. Jul 16, 2014 #9


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    If Hawking didn't have the physical devices built by other humans, he would have been dead long ago.

    intelligence on its own is fairly useless. But intelligence plus opposable thumbs is a different ballgame.
  11. Jul 16, 2014 #10
    Yes, it obviously is. If he were born 100 years ago, he would have died a long time ago, no matter what his intellect was. Furthermore, if somebody with Einstein's intellect was born right now in South-Sudan, then his intellect would also not mean very much to the person.

    It certainly is now, because we have created a society of intelligent beings. We are talking about evolving to humanlike intelligence. Which means that the species in question does not yet have humanlike intelligence.

    I'm sorry, but I fail to see the evolutionary benefit of coming up with GR.

    Opposable thumbs, walking on two legs, a changing environment which made evolution necessary to survive, having eyes so we can see, ...
  12. Jul 16, 2014 #11


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    One could say that human ancestors were in the right place, at the right time, had the right prerequisites, and went through the right circumstances to develop intelligence and use it to their benefit. Aren't we lucky!
  13. Jul 17, 2014 #12
    What does that have to do with intelligence being detrimental to the suvivability of a species? If anything, the fact that human intelligence is able to build devices to keep Stephan Hawking alive is evidence that intelligence confers a survival advantage. Plus, every individual and species relies on the cooperation of conspecifics in order to survive

    Who is talking about intelligence on its own? We're not talking about locked in syndrome here. The OP's question I believe relates to healthy individuals and populations of human and nonhuman species.

    "I just typed this entire sentence in quotes without using my thumbs, promise."

    Ok, this is better now. I am glad I have my thumbs, don't get me wrong. My point, though, is that if the entire human population lost all their thumbs today, or even other appendages, human society would not just stop and wither away. Intelligent creatures, whether human or nonhuman, find ways around physical challenges and limitations by using their intelligence, that's what intelligence means. This not only happens on communal scales but also individual scales. Galileo overcame the lack of a "zoom" feature on his eyesight by inventing the telescope with his intelligence. Benjamin Franklin cured his presbyopia by inventing bifocals, writing to his friend George Whatley in 1784 that he was "happy in the invention of double spectacles, which serving for distant objects as well as near ones, make my eyes as useful to me as ever they were."

    So, I guess I'm just not seeing what evidence there is that a lack of intelligence, whether it's an isolated "locked in" intelligence or a motorically expressible intelligence, confers a survival advantage in an individual or its species. If that's what the argument is here.
  14. Jul 17, 2014 #13
    This was response to my comment that intelligence was of limited advantage in survival. I am completely serious.

    Archaea are not intelligent.
    Bacteria are not intelligent.

    That's most of the organisms on the planet and they are surviving rather well.

    If you want to consider prokaryotes only, I don't see much intelligence in plants, or a large part of the animal kingdom.

    Of course intelligence is of value in human survival, but the vast array of organisms that survive perfectly well without it, suggests the advantages it confers are limited.
  15. Jul 17, 2014 #14


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    I don't think I agree with this. Most organisms, especially single cell organisms, are not complex enough to develop intelligence. Intelligence seems to require a certain amount of complexity. In general, the more intelligent an organism is, the more complex it is. Complex organisms occupy different niches than simpler ones and have different advantages and disadvantages, so I don't think it's fair to say that the benefits of intelligence are limited. I'd argue that the benefits of intelligence are many, but it requires more complexity than most organisms have and takes specific evolutionary steps to reach it.

    It seems to be more of a case that intelligence is extremely beneficial, as a great many organisms have varying levels of it, but high level intelligence is extremely difficult to reach.
  16. Jul 17, 2014 #15


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    There is little doubt intelligence has evolved and increased over geological time. The evolutionary pressure is fairly obvious; smarter prey encourages smarter predators and vice versa. Just about every organism is subject to evolutionary pressure. Intelligence is one adaptation that has utility for complex organisms. The interesting thing about human intelligence is it took a rather dramatic leap a couple million years ago. We went from simian to human levels of intelligence in a remarkably short period of time. Equally remarkable is that we have survived as long as we have. Mitochondrial DNA studies suggest humanity was nearly driven to extinction 150,000 years ago during a particularly severe ice age. We were again at the brink 70,000 years ago in the aftermath of the Toba supervolcano eruption. And these are just the events we know about. Without a fair bit of luck, intelligence is not overly impressive as an evolutionary advantage.
  17. Jul 17, 2014 #16
    What makes you think it's luck that got humans through the ice age and and the Toba eruption? Each of which from a survival challenge was signified by a dramatic cooling of the planet as well as an accompanying destruction of much of the natural vegetation and animal food sources. From: http://en.wikipedia.org/wiki/Toba_catastrophe_theory

    Where is the evidence that it was luck that got humans through these bottlenecks?

    Doesn't it make more sense that humans may have been able to survive these catastrophes because of their use of their intelligence to create and tame fire, build shelters, make clothing, preserve foods through salting them, drying them, and cooking them, and communicating through gestures and likely spoken language? My guess is that it was the humans that were able to leverage these intelligent traits that were the ones to survive the bottleneck, not the dumb ones that couldn't rub two sticks or stones together to create a spark for a campfire.
  18. Jul 17, 2014 #17


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  19. Jul 17, 2014 #18


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    More seriously though I think there's also an energy conservation issue. Maintaining a highly functioning, conscious brain requires a very stable metabolism that's constantly burning a lot of calories and you have to have some very specific conditions for such a system to evolve.
  20. Jul 18, 2014 #19


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    I think what you are referring to is the conscientious ability of humans to adapt to environmental conditions. In that regard, we would have to be one of the more successful species on this planet.
    Humans occupy all regions of land mass with its variable temperatures and other conditions, survive on water, below water and even is space, and if advanced intelligence allows us to use technology to do so, then the level of intelligence does matter.

    One could make an argument that the gut bacteria of humans are just as successful as humans, and will be no matter where humans go, either on land, sea, air, or space, but the condition here is that their niche environment does not change, but they will be just as evolutionary successful as humans in the short or long term.

    Question is, what is evolutionary success? amount of biomass, longevity, position on the food chain, use of tools, information gathering, member of an arbitrary biological classification ( done by humans ), sentience, ...?
  21. Jul 18, 2014 #20
    Wow, I'm (almost) speechless. What a marvelous eloquence in that post, 256. I'm grateful for an ally here.

    As such, I feel compelled to try to address your query, 'Question is, what is evolutionary success?'

    That is a good question. Sorry to not sound more sophisticated, But..

    It is obviously about staying alive and procreating (to the max ;) I can't think of anything else...

    If I think of anything, I'll post it.
  22. Jul 20, 2014 #21
    That depends on how you define [species-]like intelligence. By definition, you have intermediate stages so any one trait isn't defining a species as such. Relevant here, intelligence isn't part of what defines a human. Not even hominins, where suggestions rather would be akin to our small canines, a truly unique trait among hominids.

    So this part of the question is specie-centric.

    There is very little of intelligence that seems derived among hominins. So far I know of the ability to plan ahead (corvids have problems there), suggest behavior when mentoring (chimps show but do not suggest), and handle combinatorial languages. Technology (tool use) is known among mollusks and fishes, contextual languages among birds and apes. The "complex" part here is a matter of timing, we are the first to evolve such.

    So this part of the question is selection bias.

    A more compelling question, since the specie-centric part fails, may be to ask if we will be alone in evolving the biased part.

    Biologists commonly suggest so, specific traits are rare unless the environment promotes channeled evolution. (Such as when ocean living fishes, reptiles and mammals evolve similar body shapes.) The question why Homo evolved complex technology/language and if it suggests such a channeling is open.

    So have other animals, even hominids (chimps).

    No. Which is why you don't quote references no doubt.

    - The latest population models accounting for Neanderthal and Denisovan core genes show that Africa had a population that oscillated between 10-20 000 humans. No severe bottleneck seen. ["The complete genome sequence of a Neanderthal from the Altai Mountains", Pääbo et al, Nature 2013]

    - How much the Toba eruption affected the population, even close by, is entirely unconstrained. That people repopulated the area shortly after suggests that the effects were very local. [ http://en.wikipedia.org/wiki/Toba_catastrophe_theory ]

    To sum up the problems with these claims, they were based on mitochondrial evidence which is generally a poor informant and in this case have been efficiently refuted by whole genome sequencing.
  23. Jul 29, 2014 #22
    Intelligence certainly has an advantage to survival. I'm not saying that intelligence alone has an advantage to survival. I never said that. Blind humans have a higher survival rate than blind "animals". A blind animal will only survive if there is a human to take care of it.
  24. Jul 29, 2014 #23


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    I'm not sure I agree. A lot of animals depend on their other senses more than humans do and can adapt to blindness.
  25. Jul 29, 2014 #24
    And yet, I stepped on a cockroach this morning...

    Intelligence is certainly advantageous to humans. And, it seems that it is advantageous to other animals which find themselves in ecosystems with other intelligent predators. I don't think anyone is disputing that.

    Intelligence is one of the traits that helped us overtake similar species, evolutionarily. We are mostly hairless, relatively weak given our size, we can't see well at night, we have no natural defensive traits (like a thick hide or poisonous sweat glands) nor offensively advantageous traits (like claws or sharp teeth) besides our thumbs. We exist because we are intelligent, and it happened by luck that our species was able to develop that intelligence to what we have now. We are the dominant species of the planet and the unrivaled predator of all ecosystems (if we choose to be). Sure, a shark can get us in the ocean, or a tiger in the jungle, but give me a submarine and some torpedoes, or a tank and some shells and I'll have dinner ready by six. Yet we are, in most other respects, unimpressive as a predator.

    ...my original point being, although intelligence has undoubtedly helped us evolve and survive as a species, cockroaches have survived for millions of years and have not developed any "intelligence" because they get along perfectly well without it.
    Last edited: Jul 29, 2014
  26. Jul 29, 2014 #25


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    With 'considerable' effort, I rounded up a couple references.
    http://news.nationalgeographic.com/news/2008/04/080424-humans-extinct_2.html, After Near Extinction, Humans Split Into Isolated Bands

    A causal relationship between the population bottleneck and the Toba super-eruption is in dispute - e.g., http://ice2.uab.cat/argo/Argo_actualitzacio/argo_butlleti/ccee/geologia/arxius/4Gathorne-Hardy.pdf, The super-eruption of Toba, did it cause a human bottleneck?
    There is, however, little dispute a population bottleneck existed around that time.

    Reference requests are welcome. Dismissive remarks are not.
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