
Why Humans and Their Fur Parted Ways - mgcreed
http://www.nytimes.com/2003/08/19/science/why-humans-and-their-fur-parted-ways.html
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arketyp
The hypothesis fails to explain why this adaption is unique to humans. Lice
probably was just as big of a problem for other animals in similar habitats as
it was for humans. The question is what element in human evolution made the
benefit of not having fur greater than the benefit of having it. Sexual
selection seems far-fetched.

I like the idea of the discovery and invention of maintaining fire as being
that element. It is known that modern hunter-gatherers hunt and catch their
pray in long distances by exhausting them, and our ancestors probably did the
same. Not having fur is of great advantage in this scenario as it allows for
effective cooling when sweating, while the obvious down-side is freezing at
night. With the taming of fire, freezing could be avoided by staying close to
the hearth, and so fur was no longer needed and we lost it.

I recommend "Catching fire" by Richard Wrangham for further investigations on
how fire shaped our evolution. It's quite a good read, and a very interesting
hypothesis.

[Edit: Gave the book's subtitle instead of the real title.]

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asdlfj2sd33
I could have sworn the parasite theory is very old. I even recall genetic
studies of human head and pubic lice vs. ape and gorilla lice. The genetic
history of the lice matched nicely with our hair loss genes.

And I have no trouble believing this, as well as hunting by running down, and
sexual selection and fire all contributed to our hairlessnes.

Sexual selection in particular is very powerful. It routinely spawns new
species. Just one female that prefers something different in males, can
quickly lead to a reproductively isolated population.

Just about the only thing that I don't think is a factor is an aquatic ape
phase.

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jacobolus
Yes, it’s quite interesting, it turns out that human pubic lice share closer
ancestors with gorilla lice than either chimpanzee or human head lice do,
while those species are quite close to each-other. Which means that when
humans became hairless, their lice adapted to living on their heads and
stopped living all over the rest of their bodies, leaving a perfect ecological
niche (pubic hair) for gorilla lice to jump into. The evolution of "body lice"
likewise corresponds with the earliest uses of clothing.

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russell
I have long felt that sexual selection dominates random mutations for external
features. My guess is that darker skin enabled sexual selection for
hairlessness. I can see where smooth healthy skin would be more attractive
than monkey hair. If these characteristics appeared in a relatively isolated
population, the evolution to nakedness by sexual selection could be quite
rapid.

I give little credence to just-so stories like nakedness evolved to free us of
parasites. Viewing human evolution as dominated by sexual evolution with a few
tweaks from mutations, like darker skin, makes more sense to me. Head hair and
pubic hair are purely sexual.

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jawngee
I prefer the aquatic monkey theory.

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mapleoin
I prefer the creationist belief.

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mapleoin
did you upvote me because you thought I was being ironic?

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mapleoin
hahahahaha. I thought so

