Animals as stock are a reproducible, living resource. Herbivores can be kept in herds or flocks in considerable numbers, sometimes ranging over extensive pasture grounds, while omnivorous animals tend to be kept in smaller numbers, typically closer to the homestead. For millennia, people in different parts of the world have learned to work with or “manage,” their animals' particular characteristics. Herd animals supply raw materials, food, and labor service; people also value their companionship and sometimes regard them as intermediaries between mortal beings and divinities. In pastoralist and agricultural societies, livestock management is often accompanied by ritual practices intended to ensure the wellbeing of the animals. Everyday management of herds focuses on ensuring access to adequate pasture, often in marginal environments. Under ranching conditions, extremely large numbers of animals may be stocked and owners tend not to develop the systems of respect and close communication possible between herders and livestock in subsistence economies.