the topics in which studies on birds have figured prominently include the mechanisms of species formation , the regulation of the distribution and abundance of animals , the effects of the environment on behavior and physiology , the biological and evolutionary significance of variations in social organizations , the encoding of information in animal communication , the sensory basis for migration and navigation , the effects of hormones on nerve cells and behavior , the ontogeny of brain and behavior , and the structure and function of the vertebrate brain .
C0006104
brain
C0004927
behavior