The dugong is a marine mammal. It is one of four living species of the order Sirenia, which also includes three species of manatees. It is the only living representative of the once-diverse family Dugongidae; its closest modern relative, Steller's sea cow, was hunted to extinction in the 18th century.
Dugong
Dugong skeleton displayed at Philippine National Museum
Bones in the forelimb can fuse variously with age.
Dugong tail fluke
Marine mammals are mammals that rely on marine (saltwater) ecosystems for their existence. They include animals such as cetaceans, pinnipeds, sirenians, sea otters and polar bears. They are an informal group, unified only by their reliance on marine environments for feeding and survival.
A humpback whale (Megaptera novaeangliae)
A leopard seal (Hydrurga leptonyx)
A polar bear (Ursus maritimus), a member of family Ursidae
A sea otter (Enhydra lutris), a member of family Mustelidae