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Did Snakes Help Build the Primate Brain?

Posted by Unknown on from the snakes-on-a-brain dept.

sciencehabit writes "A new study of the monkey brain suggests that primates are uniquely adapted to recognize the features of snakes and react in a flash. What's more, by selecting for traits that helped animals avoid them, the reptiles ultimately endowed us with forward-facing eyes, for example, and enlarged visual centers deep in our brains that are specialized for picking out specific features in the world around us, such as the general shape of a snake's body camouflaged among leaves.The results lend support to a controversial hypothesis: that primates as we know them would never have evolved without snakes."

8 of 202 comments (clear)

  1. Not sure why this would be controversial. by Anonymous Coward · · Score: 4, Interesting

    Surely, a basic consequence of the mechanisms involved in evolution is that all long term changes in individual species are effectively driven by factors of the environment they live in, whether that's predators or other dangers, or the needs of being able to acquire food or raise offspring, etc. Snakes are, we know, dangerous. So surely it's obvious rather than controversial that they should have had some effect on our evolution?

    1. Re:Not sure why this would be controversial. by AC-x · · Score: 3, Interesting

      Given the myriad other hazards, and billions of other reasons that stereoscopic vision in hunter-animals evolved, the answer is pretty much No.

      Except the primates that humans evolved from weren't predators yet have binocular vision.

    2. Re:Not sure why this would be controversial. by m00sh · · Score: 5, Interesting

      The question is: Is it enough to be relevant?

      Given the myriad other hazards, and billions of other reasons that stereoscopic vision in hunter-animals evolved, the answer is pretty much No.

      This is why it's controversial. It's "true" while also being absolute bollocks. It's like saying that without lead-acid batteries, cars wouldn't have evolved as they have. Well, no. But it doesn't mean that without lead-acid batteries cars couldn't have existed or anything like that.

      P.S. The "wading in water made man stand upright" is just as controversial because, although it may be a FACTOR, the impact of that factor is the crucial question. It may well be zero. It may well be quite a lot. But chances are that it's such a minuscule factor that it's not worth spouting off about compared to thousands of other factors.

      Evolution is not a case of "jumping off this cliff made birds suddenly grow wings". There are billions of factors over millions of years and hundreds of thousands of generations that all nudge towards small changes which impact upon the previous and next changes.

      As such, this suggestion is almost complete bollocks, while being - on the surface - based on truthful data. But "snake-like predators might possibly have contributed a tiny bit to millions of years of our evolution along with million of other factors" isn't a headline that sells papers to journals.

      Have you heard of the pareto principle? Even if there are millions of factors, one factor will have a much higher influence than others.

      In the economy, 1% control 90% of the wealth. In the movie industry, the top 1% of the movies rake in 90% of the movie revenue. On earth, 1% of the species occupy 90% of the ecosystems. You get the idea.

      If there were a thousand reasons that influenced equally, it would be a rare natural system. Most often, natural systems are unstable dynamical systems and have positive feedback systems where one factor gets amplified much more than others that additionally feedbacks on itself where 90% of the influence is due to one factor.

      The initial reason why one factor is amplified over others could be down to just random fluctuations. A small random fluctuation could be amplified over and over again to create a dominating effect. So, there is no way someone can sit here and argue that this reason sounds better than that because the influencing factor can be random among the possible set of factors and only by doing field studies can the influencing factor be verified.

    3. Re:Not sure why this would be controversial. by TapeCutter · · Score: 4, Interesting

      I'm pretty sure humans ate snakes more often than the other way around, even here in Oz with 9 of the top 10 deadliest snakes, most species are harmless and quite tasty. As for humans being adapted to spot them, snakes are experts at hiding in plain view, even the aborigines who still hunt them will tell you it's very difficult to spot them until they move. The rattlesnakes of the US, the colourful sea snakes, and a few others species are unusually polite poisonous snakes since they clearly advertise their presence and lethality to anything that comes close. Most Aussie snakes will just sit there looking exactly like a stick until you're practically standing on them. I can't count the number of times I've had the shit scared out of me by a snake bolting for the undergrowth at the last minute, it's not much comfort knowing the snake shit itself more than I did.

      --
      And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
  2. Also bird brains by taleman · · Score: 4, Interesting

    Seems also birds are afraid of snakes. I place rubber snakes on places like boat decks and balconies, they are very effective and birds stay away.

  3. Feline brains too by Anonymous Coward · · Score: 2, Interesting

    Cats are not thrilled with things like vacuum cleaner hoses and air hissing sounds.

  4. If snakes didn't exist you'd have to invent them by PhilHibbs · · Score: 3, Interesting

    There is a niche for a small, fast, deadly predator. Snakes happen to have won the fight for that niche, and so it's them that we have evolved to spot. If it weren't for the snakes, we woud still exist because something else would exist that we had a need to spot and react really quickly to. Screw you, snakes, you're not all that.

  5. Total Bullshit by The+Cat · · Score: 3, Interesting

    This is the problem with modern "science." Any consistency and color of shit can be shoveled as long as someone pulls something vaguely rational-sounding out of their ass and calls it science.

    Forward-facing eyes evolved for predators, not prey. They allow for judging of distance and depth, something a predator needs in order to chase. See lions, raptors, wolves, bears, etc.

    Side-facing eyes evolved for prey, so they can perceive a wide viewing angle for movement and differences in texture/shade. See antelope, horses, deer, rabbits.

    Primates evolved to take advantage of their hands. Enlarged visual centers for climbing and enlarged heads for the brains required to start using tools.

    Fuck, and I'm not even a scientist. This "let's see how much utter horseshit we can label science" routine is getting really tired.