Archeologists estimate that, in ordinary circumstances, the activity of gathering in temperate and tropic areas provides 75 to 80% of the total calories consumed, with hunting providing the balance. In existing hunting and gathering cultures, women usually do most of the gathering, while the men specialize in hunting. Other than this kind of gender specialization--and it is by no means universal--there is little specialization of roles within the group. Hunter-gatherers tend to accumulate a large and intimate knowledge of their range and the food sources, dangers, and opportunities which exist within it. And this knowledge is largely communal; it is shared by the group.
Hunter gatherer societies typically enjoy a surprisingly diverse diet and abundant leisure. They live in a small, personal world defined by the band, which seldom consists of more than 250 people. Since young people usually marry outside of the band and hunter gatherers have no accumulated wealth to steal, their attitude toward outsiders tends to be cautiously friendly rather than hostile.