Francis Orlando wrote:
> - Humans do not seem to be efficient meat eaters without tools.
>   Is the thesis that tools make us omnivores and that this is an adaptive
and evolutionary-driven requirement now?
>

People seem to have been eating meat using tools for at least 2
million
years ( ie homo erectus or similar).  This from a site in
Europe,dating
a skull in an area with piles of mammal bones (rhino, hippo, ...).

My take is that prior to tools it would have been a tough ask to bring
down a rhino or hippo!!!  However, scavenging on dead or dying animals
would have been possible.

Lynton

PS - re blood type:
the oldest blood-type is O, D'Adamo suggests that A (I think 30,000
years) was followed by B (maybe 5000).  AB is when A's and B's got
together, and is the youngest.
The basic idea differentiating foods for the different groups is due
to
the lectins that interact with the immune system.