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Pinniped
Pinnipeds (pronounced ), commonly known as seals, are a widely range (biology), distributed and diverse clade of carnivorous, fin-footed, semiaquatic, mostly marine mammal, marine mammals. They comprise the extant taxon, extant family (biology), families Odobenidae (whose only living member is the walrus), Otariidae (the eared seals: sea lions and fur seals), and Phocidae (the earless seals, or true seals). There are 34 extant species of pinnipeds, and more than 50 extinct species have been described from fossils. While seals were historically thought to have descended from two ancestral lines, molecular phylogenetics, molecular evidence supports them as a monophyletic lineage (descended from one ancestral line). Pinnipeds belong to the order Carnivora; their closest living relatives are Musteloidea, musteloids (Mustelidae, weasels, Procyonidae, raccoons, skunks, and red pandas), having diverged about 50 million years ago. Seals range in size from the and Baikal sea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine Mammal
Marine mammals are aquatic mammals that rely on the ocean and other marine ecosystems for their existence. They include animals such as Pinniped, seals, Cetacea, whales, Sirenia, manatees, sea otters and polar bears. They are an informal group, unified only by their reliance on marine environments for feeding and survival. Marine mammal adaptation to an aquatic lifestyle varies considerably between species. Both Cetacea, cetaceans and Sirenia, sirenians are fully aquatic and therefore are obligate water dwellers. Seals and sea-lions are semiaquatic; they spend the majority of their time in the water but need to return to land for important activities such as mating, breeding in the wild, breeding and molting. In contrast, both otters and the polar bear are much less adapted to aquatic living. The diets of marine mammals vary considerably as well; some eat zooplankton, others eat fish, squid, shellfish, or sea-grass, and a few eat other mammals. While the number of marine mammals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
