Evolutionary ecologists study the selective forces that shape morphological, physiofogical, behavioral and life-history traits. Parasites are among the strongest selective agents to influence all traits related to survival and reprodüction of their hosts, and are at the origin of the large diversity of animals and plants on earth. The book-length exploration of behavioral mechanisms in evolutionary ecology, this ambitious book illuminates long-standing questions about cause- and-effect relations between an animal's behaviour and its environment. By focusing on biological mechanisms-the sum of an animal's cognitive, neural, developmental, and hormonal processes-leading researchers demonstrate how the integrated study of animal physiology, cognitive processes, and social interaction canield an enriched understanding of behavior.