"They eat lots of tubers because they are widely available and they eat less meat and honey because they aren’t always available (even though they prefer the latter two). Before agriculture and the rise of the state, land was sparsely populated by humans and rich in game. Animals were simply more numerous and thus easier to come by. I’m not saying that our ancestors were carnivores – quite the contrary, in fact – but all else being equal hunter-gatherers on game-rich lands will have more opportunities to consume (the preferred) animals and less cause to fallback on fibrous tubers than hunter-gatherers on marginalized lands."
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