Avian Biology, Volume VI is a compendium of papers that deals with selected aspects of avian biology. One paper discusses the avian mating behavior and covers topics such as monogamy, polygyny, male incubation, and female emancipation; these papers also list a table of the species of birds in which polyandry has been observed. Another paper examines bird migration in relation to the mechanism and development of migration with emphasis on the evolution and function (ultimate causation) of migration. Another paper discusses the advantages of one form of social organization of birds during the non-reproductive season over another form. This paper reasons the possibility of the existence of a cost-benefit social behavior. Other papers discuss some physical features found in birds such as stomach oils and glycogen-filled cells. Another paper deals with the respiratory physiology of birds as new research data have been made available in this area. This book can prove useful for investigators in avian biology, zoologists, and readers who have a general interest in birds.