Why do modern human beings have very little body hair compared to their ancestors?

[No_Me_Ayudes_Compadre]

About half a year ago the NY Times had an item with another theory.

And here’s a link to the full text!

Dr. Alan R. Rogers, an evolutionary geneticist at the University of Utah, has figured out when humans lost their hair by an indirect method depending on the gene that determines skin color. Dr. Mark Stone- king of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, believes he has established when humans first wore clothes. His method too is indirect: it involves dating the evolution of the human body louse, which infests only clothes. Meanwhile a third group of researchers, resurrecting a suggestion of Darwin, has come up with a novel explanation of why humans lost their body hair in the first place.

dot dot dot dot

Humans lost their body hair, they say, to free themselves of external parasites that infest fur — blood-sucking lice, fleas and ticks and the diseases they spread. Once hairlessness had evolved through natural selection, Dr. Pagel and Dr. Bodmer suggest, it then became subject to sexual selection.

For what it’s worth.

[John_Mace]

@The Gaspode

I might not remember this correctly, but I read somewhere that humans and chimps have the same number of body hairs, it’s just that heirs is courser, thicker and longer.
If that’s the case, then we don’t have less hair, just finer.

Roughly true. Look at the back of your hand and imagine each of those hairs was 3 cm instead of < 1 cm.

plnnr: Sorry if I sounded snarky in my earlier post. I also confused your reply with the original post from flapcats. At any rate, you’ll find that Australian aboriginals and Ainu (in Japan) to be about as hairy as Europeans. I don’t think anyone has found a correlation between climate and hairiness.

[Milum]

I don’t know. But what I do know is that that the traits that are selected by evolution, are not designed to correspond with our neat semantical capsules of single function designations, but rather, they are evolutionary functions of cause and effect determinates of languageless factors that contribute greatly towards our survival as a kind. This is another way of saying that many, maybe most, of the ideas offered here so far in this thread could be simultaneously effective towards effecting the relative hairlessness of humankind.

But I don’t think so. I think that the squench who wrote the book claiming that our ancesters spent a few hundred thousand years wallowing around in ancient seas was probably right. For us to evolve from nice warm furry animals to naked folks as we are today, would seem to require a dramatic environmental change, far beyond the scope of dinky little ice ages, and then only then , after our adventuresome wading about and losing most of our precious body hair, could we muster a triumphant return to the terrestrial dry world that we live in and love in and rule in today.

What else could make us so wonderfully different?

[Kaotic_Newtral]

Stupid Theory Coming Up!
How about this? We don’t ‘need’ the hair. If I’m not mistaken, Eskimos don’t have particularly hairy bodies and they need all the insulation they can get. I’m guessing that it’s just a hereditary cling-on that has survived. It’s been nothing that has ‘had’ to disappear, and it hasn’t been detrimental to the survival of the species. Maybe, just maybe, it’s in the same class as brown hair, blonde hair, red hair and black hair color. It’s just one of those ‘things’ that isn’t something that hasn’t been particularly substantial in the selection of mates and continuation of the human race.

Certain things (to me) seem to be easily surmised. Folks from equatorial climates seem to have more melanin production that peoples that are otherwise inclined towards either the North or South. That, in itself actually seems to be a survival mechanism. The amount of body hair on the other hand, doesn’t. (IMHO)

To me, we’re all the same…except for extraneous features.

0.02
-K