For students of animal behavior, dominance refers to the phenomenon by which individuals of a social species organize themselves with regard to access to resources. Although some social species appear to be egalitarian in many respects, close observations reveal differential access among individuals in nearly all cases, especially when resources are in short supply. These resources may include food, nest sites, mates, or any other considerations that have consequences for evolutionary success, or fitness; a dominance hierarchy is one of the most common patterns whereby access to these resources is established.

Dominance Hierarchies and Relationships

Although dominance relationships have in the past been seen as a species characteristic in themselves, they most importantly reflect differences in size, aggressiveness, and/or motivation among individuals, with these differences generating, in turn, a hierarchy of access to fitness-enhancing opportunities. It also appears to be beneficial to individuals to recognize their competitive...