Reproductive Behavior

Reproductive behavior refers to the orderly sequence of behavioral events that are associated with reproduction, and it includes courtship, copulation, nest building, oviposition, incubation, and parental behavior. Reproductive behavior in vertebrates is thought to have evolved long before the ascent of birds. Presumably as a result of this ancient origin and the adaptation of birds to living in most terrestrial ecosystems, avian reproductive behavior as a whole and its individual components are extremely diverse with regard to complexity, duration, seasonality, and control mechanisms. Despite this diversity, avian reproductive behavior is proximately regulated by a large, but in many instances rather conserved, set of (neuro)hormones. This chapter draws from a variety of avian models to address aspects of this regulation. It emphasizes the fact that in addition to being controlled by (neuro)hormones, reproductive behavior is influenced by an array of environmental factors and social interactions. A major impetus of research on avian reproductive behavior is to identify the mechanisms by which internal and external factors govern the expression of this behavior, and to determine how organisms integrate the influence of these factors and transduce this integrated information into time- and context-appropriate behavioral responses.