Social influences on foraging in vertebrates: causal mechanisms and adaptive functions

We summarize 20 years of empirical and theoretical research on causes and f unctions of social influences on foraging by animals. We consider separatel y studies of social influence on when, where, what and how to eat. Implicit in discussion of the majority of studies is our assumption that social inf luences on foraging reflect a biasing of individual learning processes by s ocial stimuli rather than action of independent social-learning mechanisms. Our review of theoretical approaches suggests that the majority of formall y derived hypotheses concerning functions of social influence on foraging h ave not yet been tested adequately and many models are in need of further r efinement. We also consider the importance to the future of the field of in tegrating 'top-down' and 'bottom-up' approaches to the study of social lear ning. (C) 2001 The Association for the Study of Animal Behaviour.