snip]
> I certainly see a use for bipedalism on the savannah, just look at
> meerkats. On flat plains with high grass, the higher you can stand, the
> earlier you get a warning of predators. Additionally, the ability to
> throw rocks and spears with decent power over decent distance also
> mandates an upright, high stance with a hip structure that also is
> conducive to bipedalism over quadupedalism. Those who could throw the
> spear the hardest and furthest got the best meat, and therefore were the
> alpha males that got to reproduce.
>
> This is a fine example of technology effecting evolution. Due to the
> computational demands of intuitive trajectory calculation, and the
> communication demands of hunting in teams or packs, lager brain cases
> were seen as an evolutionary advantage. WHile the analytical abilities
> of hunting were amplified in males, the females who had to look after
> offspring had to coordinate defenses against predators whil the males
> were hunting, so they developed better communication skills.
>
> Want to prove this is so? Try to teach a chimp to throw a 90 mph
> fastball on a major league field in the strikezone. It'll never happen.
> He doesn't have the hips for the job.
The best exploration of the evolutionary trajectory from something chimp-like
to something human-like has been done by William Calvin. (Try that name and
Ascent of Mind in any search engine to get to his web site.) Chimps lack the
release timing accuracy to throw rocks and hit small targets, they simply
don't have the number of neurons in parallel to reduce the scatter. But
brains large enough to hit small targets are much more recent than proto
humans hunting. How did they do it? Perhaps the most common tool in the
old stone age took kit was a thing called a hand ax. How these things were
used was the subject for a lot of unsatisfactory discussion until Calvin
suggested they were thrown like a discus into groups of animals at a
water holes.
Of course, proto humans hunted with hand axes for millions of years
before the big brain expansion during the ice ages. Calvin connects how
ice ages and brain expansion may be causally related.
Calvin may not have the last word on this subject, but I would strongly
suggest that anyone who wants to speculate on the origins of human
hunting skills and larger brains absorb Calvin's thoughts on the subject.
Keith Henson