Amadeus Schmidt wrote:

> I couldn't let stand that human brain developenent would be dependent on
> scavenging of zebra skulls.
>
> I'd appreciate further comments (on topic).


I tend to agree. Scavenging lions kills would be dangerous
business. Hyenas are well and long adapted to just this
niche, but lions kill them all the time, the way we squash
roaches. Humans are a lot
slower and weaker than hyenas. Plus we would have had to
drive the hyenas away too. And if we were dangerous enough
to actually drive lions off a kill (which a pack of hyenas
sometimes accomplishes with a lone lion) then we must have
been tough enough to do our own hunting.

I suspect the answer is simpler. We hunted smaller animals a
lot, and at them whole and raw, lots of bugs, slugs, fish,
turtles, eggs. Humans are a lot better at catching all these
things than most other predators. We have a far wider range
of possible prey, plus the advantage of being able to eat
lots of plant foods too, than any animal you can name.

Any hominid already smart enough to chip rocks reliably must
have had a pretty broad material culture. Digging sticks,
water bags, tote bags, all sorts of things that made getting
a reliable food intake easier, fueling big brains. Circular
logic? So what.