Cows, Pigs, Wars, and Witches: The Riddles of Culture

by Marvin Harris

The basic reason for this is that the world zones of pastoral nomadism correspond to unforested plains and hills that are too arid for rainfall agriculture and that cannot easily be irrigated. The domestic animals best adapted to these zones are the ruminants—cattle, sheep, and goats. Ruminants have sacks anterior to their stomachs which enable them to digest grass, leaves, and other foods consisting mainly of cellulose more efficiently than any other mammals. The pig, however, is primarily a creature of forests and shaded riverbanks. Although it is omnivorous, its best weight gain is from food low in cellulose—nuts, fruits, tubers, and especially grains, making it a direct competitor of man. It cannot subsist on grass alone, and nowhere in the world do fully nomadic pastoralists raise significant numbers of pigs. The pig has the further disadvantage of not being a practical source of milk and of being notoriously difficult to herd over long distances.