The application of economic principles to animal behaviour. The animal is treated as a consumer, as in human microeconomics. It is assumed that the animal is a rational decision-maker, maximizing utility (or an equivalent) and spending time and energy in a way that parallels the expenditure of time and money by humans. The animal's budget, or limit to expenditure, of energy or time, constrains its behaviour. Thus an animal cannot devote more energy to an activity than it has available at the time. Nor can it devote more time than is available (per day).
Experiments with animals show that they exhibit characteristic demand functions, a concept borrowed from economics to express the relationship between the price and the consumption of a commodity. For example, if an animal expends a certain amount of energy on a particular activity, then it usually does less of that activity if the energy requirement is increased. The elasticity of demand functions in animals gives an indication of the relative importance of the various activities in the animal's repertoire, and demand functions are closely related to behavioural resilience.
Subjects: Zoology and Animal Sciences.