How does decision theory explain an animal’s choice between different actions?

Decision theory provides a framework for understanding how animals select among alternative courses of action by assessing the costs and benefits associated with each choice in a given situation. Rather than implying that animals perform conscious, rational calculations, this approach assumes that natural selection has favored individuals capable of adjusting their behavior to maximize their net fitness—their genetic contribution to future generations.12

In this context, an animal’s choice is viewed as the result of competition between various potential activities. The resolution of this competition depends on weighing the positive consequences of an action, such as gaining access to food, shelter, or mates, against the negative consequences, such as the expenditure of energy, loss of time, or the risk of injury.32

For example, in aggressive behavior, an animal may choose to submit to a dominant rival rather than fight if the potential costs of injury or energy depletion outweigh the benefits of winning the encounter. Similarly, in optimal foraging theory, an animal’s decision to search for a specific type of food is influenced by the probability of finding that food, its nutritional value, and the availability of alternative resources.23