Not rejecting that theory out of hand Walter, but has that happened with any other species? Becoming naked I mean. It seems a real disadvantage. We see that today that humans are great runners, and can run down game over many kilometers of chase. Which prey? I am willing to be corrected, but I thought human hunting was a matter of stalking prey rather than outrunning it. Could you provide a few examples to support your hypothesis?
Gazelle - they run fast at first, but tire and overheat. Once they overheat, you can walk right up to them and they can't move. I've seen videos of this, but it's been awhile. I'll have to look up the old references. Now that people have weapons, yes, we've switched to stalking. But in the old days, all we had were sticks and stones, and you gotta get close with those.
Here are some more: http://www.livescience.com/2747-caveman-modern-human-win-olympic-gold.html http://www.bing.com/videos/search?q...vt=human hunter running prey down overheating
Still more: http://www.youtube.com/watch?v=826HMLoiE_o http://sports.espn.go.com/espn/news/story?id=6110087 http://alistairpott.com/2009/04/15/persistence-hunting-humans-running-antelope-to-death/
Re The nakedness of humans is an evolutionary adaptation so that human predators become less overheated in strong sunlight, and can exhaust their prey by tracking them for hours. Is no-one interested in putting up any opposition to this idea? It sounds at first like nonsense, but there is good reasoning behind it. Are you accepting it?
I think it would be quite interesting to find some sort of confirmation in some other species/type of species that also used sweat as thermoregulation. If in some of those few species, there were "wandering in hot climate" variants that were less hairy, differently from closely related species that live in a different climate or under a different "strategy". There's apparently correlated variation within humans themselves, which is even somewhat weird, as the additional body hair that Europeans or even Ainus have don't seem to be enough to make the body any warmer. Intuition is often wrong, though. I could shave my chest to test the idea, but I'm not really that interested. Having just the "shadow" of a beard seems to be enough to make the face uncomfortably warmer in hot days though, but I think it may be more psychological than something really physical. I recall reading, I think it was on Morris' "the naked ape", that humans actually don't have less body hair than chimps do, it's only shorter and thinner body hair, or at least something like follicles that don't ever "sprout", I guess. And in the same book or somewhere else our hairlessness was postulated as being some side effect of paedomorphosis, as the apes' newborns (and infants?) are less hairy. Oddly enough sometimes newborn humans have lots of body hair (lanugo), but this body hair falls off almost readily.
I don't really know anything about it, just thought it may be interesting to add here. My guess is that as we're more social/have larger groups than other primates (I guess, at least generalizing from the "Dumbar number" theory), perhaps we'd be an easier target for ectoparasites. Just occurred to me that perhaps by a similar logic, the reduction of our intestines could have been partly a strategy to scape/minimize the harm from endoparasites. But I don't know if it really makes any sense, possibly not.
It makes more sense then anything else, considering the world record holder has run more then 300 miles in a single stretch. We can run farther then any other animal including horses and dogs. There must be a reason for such an adaptation and this generally thought to be it.
Captain Kremmen didn't mention anything related to running long distances non-stop, but rather about exhausting animals while just walking and running/jogging only strategically. I'd also guess that even humans living as hunter-gatherers are not on average able to outcompete dogs and horses. This probably comes with specific conditioning for a certain hunting strategy rather than a general adaptation.
