Man is, at his core, a social animal (okay, I'm using the masculine pronoun here... bear with me, okay?). Left alone he will soon die. Early man naturally banded together because it was part of his nature - like a herd animal. Another part of human nature is the urge to dominate. A band of people living in the wilderness would, again naturally, see a leader emerge. On this level it would be like an "alpha male" in a pack of wolves.
I'm thinking proto-humans were probably banding together in groups, packs, herds... call them what you will, before they were completely human. As they continued to evolve their behaviors grew more complex and likely led to village life, animal husbandry and farming quite naturally (there's that word again!).
Quite probably the emergent lifestyles influenced evolution as much as evolution influenced lifestyles.
