Historical contributions of research on birds to behavioral neuroendocrinology.

The contributions from bird research to behavioral neuroendocrinology are enormous and wide ranging. I have selected examples that illustrate how through the twentieth century to the present day, birds as experimental models continue to play a major role. Investigations on birds were pivotal in the beginnings of endocrinology, and have laid the foundations for present day developments in neurobiology, physiological ecology and evolutionary biology of neuroendocrine systems. The extensive literature on avian behavior also provides a unique and broad base for the field in general and future progress on a broad front can be expected. Molecular genetics in avian systems is advanced providing us with phylogenetic perspective allowing the comparisons of different avian populations that provide valuable models for integrative research.