Ornithology, third edition
The leading textbook in its field, now in its third edition, Ornithology begins, appropriately, with a section on origins, discussing the diversity of birds, their evolutionary history, and their systematics. "The power of evolution by natural selection is the central theme of this book," Gill explains. "The adaptations of birds ranging from morphology and physiology to migration and mating systems are testimony to the pervasive role of Darwinian evolution in action through the millennia." The author is a former president of the American Ornithologists' Union and a former Senior Vice President and Director of Science for the National Audubon Society.