Lecture, three hours; discussion, one hour. Requisite: Life Sciences 1 or 7B. Examination of evolution, systematics, natural history, anatomy, physiology, and conservation of mammals secondarily adapted to life in oceans: cetaceans, pinnipeds, sirenians, marine otters, and polar bear. Through lectures and readings from recent primary literature, students gain understanding of special adaptations to mammalian life in aquatic environment, roles of marine mammals in oceanic ecosystems, and general principles of marine mammal population biology. Study of historical and contemporary exploitation, conservation, and management of marine mammal stocks. Letter grading.