It all depends on heredity and local food sources, Grz. Do get "Nutrition and Physical Degeneration". The Masai thrive on meat, blood & milk. Eskimos thrive on blubber, seal & reindeer liver(or something like that. Polynesians live on seafood & fruit...etc...
We are all different!
and NO culture has evolved vegetarian...vegetarianism is historically practiced for religious and spiritual reasons.