Did Snakes Help Build the Primate Brain? 202
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from the snakes-on-a-brain dept.
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."
what about badgers and mushrooms? (Score:5, Funny)
They are at least as important as snaaaaakes.
Re:Picking up shape from randomized patterns (Score:4, Funny)
Re:Picking up shape from randomized patterns (Score:5, Insightful)
The random-face-generator in the brain is uncanny in its ability to amuse simple folk like myself. Also pretty tough on youngsters afraid of the dark.
SNAKE! (Score:2)
Apple. Garden.
'Nuff Said.
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As a heterosexual male who doesn't like the outdoors, my brain would treat them the same.
Re:Picking up shape from randomized patterns (Score:4, Insightful)
Perhaps a more important differentiation to an arboreal animal would be snakes and branches. One represents safety, the other danger (and possibly lunch).
Re:Picking up shape from randomized patterns (Score:4, Informative)
AC is so right - I was in a church the other day and looked up at a glass window panel and I was like "OMG it's full of angels and faces of Jesus!"
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I brought the link. [youtube.com]
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Me: immunity to venom, like the mongoose?
Nature: nah, here take forward-facing eyes, and just be careful. NEXT!
Bullshit, this is stupid. It's a mockery of Nature.
Nature doesn't "pick"" mutations based on a cost benefit analysis. They just happen by chance. If they work and allow the species to last longer, then it gets passed on. It doesn't matter if it's the best answer. It's not like sickle cell anemia is the ideal way to prevent malaria...
Not sure why this would be controversial. (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?
Re:Not sure why this would be controversial. (Score:5, Informative)
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.
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...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.
Shouldn't the factor with the least influence be the multiplicative identity, 1, not 0?
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Re:Not sure why this would be controversial. (Score:4, 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.
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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.
But they were tree swinging and jumping, and gauging distances is certainly helped by stereoscopic vision. Being able to discern a branch (or fruit) from a bunch of leaves (pattern) would also be highly useful, and both probably had more to do with our brain development than being able to recognize snakes. It may even have been merely a serendipitous development.
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I'm unconvinced as to the wading in water bit. It might explain somewhat better breath control than other apes (but so can benefits of refined communication), or perhaps heads full of oily hair. It's true aquatic species lose body hair when they or their ancestors were exposed to direct contact with water (hippos, whales, elephants, manatee, rhinos) or in dirt (naked mole rats) for majorities of their lives (at least to breeding age), but losing hair could also be a sexual selection increased neoteny [wikipedia.org] in ma
Re:Not sure why this would be controversial. (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.
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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.
While that may be true for the specific trait of upright walking, there is ample evidence that living on the beach or very close to salt or brackish water had a large impact on human evolution. Unique things like the lack of fur, a layer of subcutaneous fat, salty tears, etc., all point to evolutionary pressures associated with a familiarity with aquatic territories.
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And thus you get chicken-and-egg situations:
Did we wade because we lived near water, or did we live near water because we could wade?
And the answer is, of course: Yes. To both. Probably. At the same time. And neither one really coming "first".
And we KNOW that we came from the water originally. Everything did, if you go back far enough. So was it a hangover from our aquatic genes, or was it us re-developing the same things later on? And again, the answer is "Yes. Probably."
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I'd like to see the methodology behind this study and the alternate hypotheses
Re:Not sure why this would be controversial. (Score:5, Funny)
I'd like to see the methodology behind this study
There's only one way to do it right, so they must have done it like this:
1. Take one set of universes, call it A, all with snakes.
2. Duplicate those universes into B.
3. Now, remove snakes from the universes in A.
4. Apply small irrelevant distortions to the universes in A and B.
5. Wait a gazillion years.
6. See if humans developed similarly in A and B.
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Obligatory Futurama:
Leela A: This is getting confusing. Why don't we call our universe "Universe A" and this universe "Universe B"?
Bender 1: Hey! Why can't we be Universe A?
Fry 1: Yeah!
Amy 1: Yeah!
Farnsworth 1: We want A!
Zoidberg 1: It's the best letter!
Fry A: We called it first. Besides, this place kinda feels like a "B", y'know?
Leela 1: Alright, you can be crummy Universe A and we'll be Universe 1.
Fry 1: Or "The Mongooses". That's a cool team name. The Fighting Mongooses!
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Then who brought the snakes back in? I'm tired of these mother f'in snakes in my mother f'in universe!
Re: Not sure why this would be controversial. (Score:4, Funny)
It's controversial, because the evidence is extremely questionable. If primates evolved to recognize snakes, then how do you explain the entire politics esction of slashdot???
You darwinists are just nuts. Eve couldn't recognize a snake before, and she has enough trouble recognizing one now. Oh, and Adam still tags along for the ride.
Re:Not sure why this would be controversial. (Score:5, Interesting)
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it's not much comfort knowing the snake shit itself more than I did
Animals that are afraid of me scare me, they're more likely to attack me when I pose no real threat. Except large animals, like bears. Those can be scared of me.
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Bears are scared of you, at least sort of. If you see one in the forest, conventional wisdom is to shout at it so it knows you're there, because it will usually avoid you. And yes, I have done this. (Well, I sang loudly at it, but same difference.)
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I'm pretty sure humans ate snakes more often than the other way around...
I'm pretty sure the evolutionary time period in question was far before apes, much less hominids, came into the picture. We carry around a lot of baggage that isn't relevant to modern humans because they were relevant to our ancestors, and there hasn't been enough evolutionary advantage in losing them. Goose bumps, for example, have a role in helping furred animals stay warm, but they do nothing for us, despite them triggering when we're cold.
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Whaddya know (Score:4, Funny)
(Yes, I was aiming for '+5 funny'... how did you know?)
Re:Whaddya know (Score:5, Funny)
The bible was right after all... it was the snakes fault after all
Actually the bible was only partially right. According to the bible, it was the snake's fault, while according to this research it was the snakes' fault.
and lemme guess.. (Score:3)
That much is plane. (Score:2)
Supporting evidence is that early primates rarely if ever flew.
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Bakunin was right after all...
"The Bible, which is a very interesting and here and there very profound book when considered as one of the oldest surviving manifestations of human wisdom and fancy, expresses this truth very naively in its myth of original sin. Jehovah, who of all the good gods adored by men was certainly the most jealous, the most vain, the most ferocious, the most unjust, the most bloodthirsty, the most despotic, and the most hostile to human dignity and liberty - Jehovah had just created A
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In other words, Ignorance is Bliss and nosy in-laws are always trying to stir shit up.
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Bakunin was right after all...
No, Bakunin was either ill-informed, or deliberately misguiding. It was the tree of knowledge of good and evil that was forbidden, not knowledge in general (oh, and touching it wasn't forbidden, just eating the fruit. [Genesis 2:16-17 [biblegateway.com]). Why was it forbidden? Perhaps because without that knowledge we wouldn't experience guilt, or shame, or fear. Without that knowledge we wouldn't be held accountable for our sins.
Re: Good, evil, perception, judgement. (Score:2)
"Three Apples for the Elven-kings under the sky,
Seven for the dwarf-lords in their halls of stone,
Nine for Mortal Men doomed to die,
One for the Dark Lord on his dark throne,
In the Land of Jesus where the Clergy lie.
One Apple to rule them all, One Apple to find them,
One Apple to bring them all and in the darkness bind them
In the Land of Jesus where the Clergy lie".
Mysteries 20:13-14
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So why were they (and in fact all life on the planet if not the universe) held accountable for the action of eating that fruit, since that was done without that knowledge?
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(oh, and touching it wasn't forbidden, just eating the fruit. [Genesis 2:16-17 [biblegateway.com]).
In a way, it depends on which verse you look at. In 3:3, Eve tells the serpent that even touching the fruit was forbidden. Naturally, that raises the question of why Eve would change what they were told.
There's a lot more subtle detail to this stuff than most people realize.
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Actually it was the woman that was ultimately at fault... read your bible.
Also bird brains (Score:5, 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.
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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.
Not all of them. I once looked out across a pond to see a heron whacking the bejeezus out of a snake. 3-foot long snake and the bird had it in its bill and was flailing it around like a whip!
Re:Also bird brains (Score:4, Informative)
Horses are no fun to be on while around snakes either. You don't have to train them to avoid snakes. So horses would not have evolved to eat grass and have eyes on the side of their head without snakes?
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It might work with small paserine birds such as house sparrows, but there are a bunch of birds that consider snakes a healthy snack. :P
Maybe the birds stay away because it's tacky and a terrible fashion choice.
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According to the logic presented in TFA, birds as we know them would not have evolved without snakes.
I have a cat who is terrified of rubber snakes. Not kidding, we had to hide my kids toys when he was young (both him and the cat). The cat appeared to be very traumatized by simply seeing a rubber snake. Felines therefor would not have evolved without snakes.
The garbage that gets posted as "science" is at times astounding.
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The forward facing eyes and huge visual cortex couldn't be because flying through trees and landing on branches requires accurate depth perception and finding food by mainly sight requires acute vision. /sarcasm
Re:Also bird brains (Score:5, Insightful)
The forward facing eyes and huge visual cortex couldn't be because flying through trees and landing on branches requires accurate depth perception and finding food by mainly sight requires acute vision. /sarcasm
Or that prey animals are prone to have side-facing eyes to see possible threats all around, but predators have front-facing eyes because they're more concerned with attacking than in being attacked.
Africa is full of felines who love to snack on monkey-like creatures, but we don't have that instinctive revulsion for cats that we do for snakes.
Just give them YouTube (Score:2)
Soon they will be programmed to love kittys!
Re:Also bird brains (Score:5, Informative)
Some do, like owls. Some don't, like pigeons.
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Some do, like owls. Some don't, like pigeons.
Some do, like owls. Some don't, like practically every other bird on the planet. Yet for some reason, they are used as examples of animals with forward-facing eyes. Sure, they can SEE in front of them, but not as well as they can see to the sides. They can perceive a moving object there, or an oncoming object, which is enough to know to turn your head to get a better view of what you're about to crash into. If birds actually had forward-facing eyes, they would look at you with both of them instead of with j
Re:Also bird brains (Score:5, Informative)
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According to this [wikipedia.org] even pigeons have a small area of binocular vision. Notice the difference between the owl and pigeon. The owl is biased toward the attack while the pigeon is biased toward the defense but they both have binocular vision in at least a small part. Look at these illustrations showing hawks [eku.edu] and crows [nature.com]. Notice the relatively large area of binocular vision. Not as big as owls but bigger than pigeons.
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Feline brains too (Score:2, Interesting)
Re:Feline brains too (Score:4, Funny)
Giant noisy sucking arms spewing out nearly a hundred decibels of unnatural noise, including in the frequencies that we can't hear but cats are very sensitive to, which starts up suddenly, chases them around the house when they hide, which their "alpha" owner tries to wrest control over but which ends up tugging them around the house chasing after the cat, and which if they get too near tries to swallow their tail.
Yeah. Must be evolution about a snake-fear... And they're scared of your car starting up while they're inside the engine because cats evolved from animals that got swallowed by bellowing mammoths with whirling stomach parts...
Idiot.
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never owned a cat I see. cats' are just as afraid of uprights with no hose. I think you have a large-penis fetish
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Coming this fall, on FOX.
Forward facing eyes (Score:5, Insightful)
I thought they were prevalent on hunting animals because stereoscopic vision was important to depth perception which is critical when attacking another animal. Are snakes the reason for raptors having forward facing eyes too?
Something else that looks like a snake? Vines used by primates to move through jungles.
Re:Forward facing eyes (Score:4, Informative)
I thought they were prevalent on hunting animals because stereoscopic vision was important to depth perception which is critical when attacking another animal
The primates that humans evolved from where primarily frugivores, however they also had binocular vision.
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They also used to move through the trees. It is very important to know just how far away that branch or vine is if you want to jump to it.
Well duh. (Score:2)
Oh course they did.
The one that told Adam to eat the apple.
Restricted Study (Score:5, Insightful)
Compared with three other categories of stimuli (monkey faces, monkey hands, and geometrical shapes), snakes elicited the strongest, fastest responses,
They compared one high value stimulus with a number of low value stimuli. How about adding a few other possibilities to the mix; predators like lions or wolves, prey animals, spiders, birds, etc. We have no idea if these other stimuli would get a greater response and, by their theory, influence primate evolution more. The study is obviously flawed.
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"Flawed" barely scratches the surface.
forward facing eyes? (Score:3)
No, forward facing eyes are not to recognise snakes. Prey species, especially the ones that are "snake bite size" tend to have eyes on the sides of their heads, so they have a bigger peripheral to detect predators. Forward facing eyes are only seen in predators and omnivores that rely on eyesight to capture their prey.
Snakes are just one form of predator or danger to humans or mammals in general. Humans, as most mammals, are very inaccurate at detecting snakes, unless they move. They are not more accurate at detecting snakes than they are at detecting any other animal, providing the level of camouflage of that animal is similar to that of the snakes. Singling out snakes to come up with a bunch of generic treats that we and other mammals have as the cause of these is bullcrap and there is no way to prove any of it. Maybe this is the sort of research a recently converted creationist or someone with a snake phobia would come up with. Snakes are nothing more than lizards that evolved to have no legs and the development of mammals saw many more forms and shapes of predators and dangers throughout their evolution that required exactly the same sort of adaptation. I challenge the writers of this paper to do a double blind test and evolve mammals again, both with and without snakes in their world and see what differences occur. Only then I will accept their proof, until then, go back to school and read up before you publish.
If snakes didn't exist you'd have to invent them (Score:4, 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.
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There is a niche for a small, fast, deadly predator. Snakes happen to have won the fight for that niche
Honey Badger don't care: http://www.youtube.com/watch?v=4r7wHMg5Yjg [youtube.com]
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. 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.
Assuming that's so...
That niche might have been taken by some sort large trapdoor spider like predator, that would erupt from hiding behind us.
So instead of evolving better binocular vision to spot them, we'd have super acute hearing to catch the rustle that gave us an extra split second warning.
we would still exist
But we wouldn't be able to drive or shoot worth shit.
evolution does not occur in a vacuum (Score:3)
What about Lawyers? (Score:5, Funny)
Why did it have to be snakes? (Score:3)
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From the lowest point of view (Score:3)
But did snakes specifically evolve to lie in wait for primates and their delicious x-factor blood? Snakes as we know them would not have evolved without delicious primate blood. Which also explains vampires.
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But did snakes specifically evolve to lie in wait for primates and their delicious x-factor blood? Snakes as we know them would not have evolved without delicious primate blood. Which also explains vampires.
Yes, and that vestigial webbing we have between our fingers is some sort of genetic holdover from a batlike ancestor.
Total Bullshit (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.
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Good and evil (Score:3)
chicken/egg (Score:2)
The theory seems tautologous?
If she's arguing that of early mammals, for the non-burrowing ones snakes were the worst predator - we aren't their only descenants.
By that logic, then ALL descendants of non-burrowing mammals should have binocular vision and forward-facing eyes which is patently not true.
If she's saying that PRIMATES specifically developed forward-facing eyes to deal with snakes, that seems less supportable when forward-facing vision is more generally found across nature in predators of all sor
I don't understand (Score:2)
How could snakes help build a brain when they have no hands?
I know this from personal experience. (Score:2)
An old, familiar feeling (Score:2)
Does anyone else remember being a child and playing "snakes in the grass"? That game always dug up what I would describe as a very primal fear that lives deep down in all of us.
Of course we couldn't have evolved without snakes! (Score:2)
We couldn't have evolved without snakes and billions of other details of our history being exactly what it was. It's exactly like the arguments that creationists use when they say that so many specific things had to be just so therefore it cannot be chance. Except... it fails to recognize that if something specific didn't happen in the past then something else would have been happening instead. Without snakes or with any other significant changes to our past some other species would have evolved. Perhap
Birds too (Score:2)
A while back I lived at a place with A/C units installed through the walls. It was nice except birds used to like to try and nest on the tops of the units, which made a terrible mess. I was going to get those spikes that are used to deter them when someone advised me different: Get some rubber snakes from the toy store and put those on top of the A/C units.
Worked like a charm. Lived there another couple of years, didn't have trouble with birds on those A/Cs anymore.
"snakes have long shaped our primate lineage" (Score:2)
And to which I say, big deal. Jaguars, spiders, raptors, poisonous mushrooms, etc, etc, etc. All of the above have. It's called their environment and snakes are no more important to a squirrel monkey than a Harpie eagle.
I've got a primate-brain-building snake right here (Score:2)
Seriously? Nobody is playing the trouser snake card?
The Truth is Painfully Simple (Score:2)
Sesame Street Song (Score:2)
From Big Bird: "One of these things is not like the others, One of these things just doesn't belong, Can you tell which thing is not like the others, By the time I finish my song?"
From the Abstract: "Pulvinar neurons responded faster and stronger to snake stimuli than to monkey faces, monkey hands, and geometric shapes, and were sensitive to unmodified and low-pass filtered images but not to high-pass filtered images."
They just choose one unfamiliar species, and based on reaction, attribute evolution to
Another article (Score:2)
Not just snakes ... (Score:2)
It's not just snakes, I think the human brain is pretty hard-wired for most forms of predator.
I was at an outdoor/fishing show once, and as I came around a corner and looked up, about 50 feet in front of me was a tiger which had been stuffed and mounted. Not having seen many tigers before, I wasn't prepared for the sheer size of the damned thing.
My brain registered an immediate "holy shit, run" -- because I suspect some primitive part of our brain is wired to say to us "you do not want to mess with that".
T
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It's not just snakes, I think the human brain is pretty hard-wired for most forms of predator.
...
Agree. Snakes weren't the only bad thing out there. Scorpions, spiders, some lizards, and various insects weren't exactly ignored either, I would imagine.
As for our forward facing eyes, Ancient Alien Theorist say... lol, sorry, can't keep a straight face when I say that. =)
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Doubtful...I for one felt dumber after seeing that film.
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Talking about "just false",
ALL land predators have binocular vision - we have binocular vision, thus derived from a predator.
The primates that humans evolved from where primarily frugivore yet had binocular vision, thus our binocular vision did not come from preying on other animals.
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Primarily frugivore. Which means secondary was?
Also, what did the progenitor of that primate eat? The fruit eater might have been decended from a preditor that saw it's preferred prey animal die off and compensated by incorporating more fruit into its diet.
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Primarily arboreal animals tend to have binocular vision, for rather obvious reasons. I've never heard of squirrels being called predators (although red squirrels will occasionally eat eggs). They need stereoscopic vision to navigate through their environment.
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Talking about "just false",
ALL land predators have binocular vision - we have binocular vision, thus derived from a predator.
The primates that humans evolved from where primarily frugivore yet had binocular vision, thus our binocular vision did not come from preying on other animals.
The primates that we evolved from may have themselves evolved from predators, possibly mouse-sized insectivores.