Social Structure. Almost all species of domesticated large mammals prove to be ones whose wild ancestors share three social characteristics: they live in herds; they maintain a well-developed dominance hierarchy among herd members; and the herds occupy overlapping home ranges rather than mutually exclusive territories. ... In that way, many adults can coexist in the herd without constant fighting and with each knowing its rank. That social structure is ideal for domestication, because humans in effect take over the dominance hierarchy.