I have wondered the same thing. It also seems (from my anecdotal experience) that some people are more predisposed to high-carb diets, and others to low-carb. G

I have wondered the same thing. It also seems (from my anecdotal experience) that some people are more predisposed to high-carb diets, and others to low-carb. Genetic diversity as an adaptation to different climates would be consistent with seasonal diets.