Few subjects more predictably animate furious disagreement and cross-purposes discussion than the origins of human warfare. Are people "naturally" belligerent? And what does that even mean? The question taps a deep old well of ideological intuition.
I believe that morality evolved in response to the problem of naturally competitive individuals living in social groups. Since social groups appeared relatively early in the evolutionary story, so would the behavioral systems that make groups coherent.
Not a day goes by when I don't eat cooked food or animal products. And not a day goes by when I don't practice yoga. Both feel better with company.