Individual differences in behavior and mechanisms of ecological differentiation on the example of fish

Abstract

In this paper we present a review of the individual differences in animal behavior as exemplified by fish. A review of the basic ethological approach to their study is given. Terms such as “temperament” are shown to be applicable to the description of stable characteristics of individuality in animals. It should be emphasized that consistency over time and across situations is the main classification characteristic of the temperament trait. We also briefly review genetic and physiological mechanisms of individuality in fish, factors affecting their development in the ontogeny, and the effects of individual experience. Temperament is shown to have significant adaptive value: in many cases natural selection maintains alternative behavioral tactics. We also consider the main quantitative models that account for the coexistence of individuals with different behavioral patterns. Finally, it is demonstrated that patterns of behavioral individuality may significantly affect population dynamics.