White Sclera

Most mutations are benign and neutral to selection. In general, selective forces only act on a very small number of traits with a small amount of pressure over a long period of time, otherwise you'd just have tons of extinctions.

Why is it common in humans? Probably just genetic drift in our early ancestors.

>>8791554
communication

>>8791568
or this

no reason really you can't have humans with a black sclera survive just as well, given they are smart enough

>>8791554
Mutations occur all the time, I don't think it's exceedingly rare

>>8791573
Only seen about three cases of it occuring in chimps, and once in gorillas.

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>>8791572
It's important that people know what other people are looking at. Makes lying harder.

can't find a picture of a single human with a black sclera

guess it doesn't happen then

>>8791585
But being a more successful liar would be an advantage, I'd think.

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>>8791607
I honestly don't think so, unless you're a politician, when you get caught you usually have to fess up. Not being a liar is the best way to go about doing my personal business

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>>8791607
Nope, educate yourself.
https://en.m.wikipedia.org/wiki/Tit_for_tat

>>8791554
Random mutation, became highly 'successful' in humans because it makes communication without speaking easier, for war, hunting, etc.

Gorillas aren't known to hunt or commit wars, but occasionally communicate with eye gestures. Probably more common and may eventually become common place for chimps as they proceed to show further hunting and warlike behaviour (making the mutation more beneficial for communication).

Anything else?

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>>8792008
Any thoughts on when this mutation started spreading? The australopithecines, or just homo?

>>8792078
The mutation itself probably has been around for a very long time, possibly even before Hominidae.

Though, it didn't start to become a dominant trait until the correct behaviours for it to become beneficial arose.

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>>8792237
Considering cooperation would be a must in an open environment, seems like it may have begun to spread in the australopithecines and was carried to both homo and paranthropus.

anyone watched that new documentary "Rise of the Warrior Apes"?

https://www.youtube.com/watch?v=dQn1-mLkIHw

hasn't been released in my country unfortunately

>>8792256
Certainly as they became gradually more sociable evolutionary pressures involving communication, or the lack thereof would have made having this mutation more beneficial.

For instance, stalking dangerous pray or enemies without giving away position with audible communication.

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>>8792286
Seems more likely to be watching out for enemies and predators, considering they were most likely opportunistic as opposed to predatory.

>>8792368
Regardless, the beneficial nature boils down to adding another layer to the ability to communicate successfully, in this case, where situations demand silence.

>>8791554

Gorillas and chimps both regard eye contact as a form of aggression.

Having dark sclera is advantageous as it allows these animals to look at one another without it being obvious that they are doing so, and thus helps them avoid starting a fight.

Having white sclera would result in that individual being singled out more often and possibly ostracized, lowering the chances that they will mate successfully and thus applying a selective pressure against white sclera in the general population.

As the ancestors to humans became less aggressive towards one another and start to actively develop communication, not only did the selection pressure against white sclera go away, it may have actually reversed. Knowing that the person you're talking to is looking at you strengthens the communication link, making that person more sociable and more likely to mate successfully and pass on the white sclera mutation.

A similar process made us develop more expressive faces and got rid of the mental link between showing teeth and aggression. Smile at a human baby and they'll probably trust you; smile at a silverback gorilla and it will probably try to maul you, as it sees you as a very aggressive and disrespectful enemy.

>>8792399
Humans still bare their teeth as a sign of aggression though.

>>8792399
>evolutionary psychology
KYS my man.

>>8792409

We also smile.

No ape expressions that include the showing of teeth are associated with positive attitudes, except for in humans.

>>8792496

>psychology is determined by the brain
>the brain is subject to evolution
>therefore psychology is also subject to evolution

get out and take your tabla rosa shit with you, nigger

>>8792596
It does have a lot of problems, though.
http://www.evoanth.net/?s=Psychology

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>>8791581
check out this rare chimp
albino with white sclera and heterochromia

>>8792623
We'll be seeing him in the next X-Men movie.
>X-Men: Jungle Class

>>8792608
What are those clickbait titles?

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>>8791599

>>8793052
contact lens