The southern elephant seal (Mirounga leonina) is one of the two species of elephant seals. It is the largest member of the clade Pinnipedia and the order Carnivora, as well as the largest extant marine mammal that is not a cetacean. It gets its name from its massive size and the large proboscis of the adult male, which is used to produce very loud roars, especially during the breeding season. A bull southern elephant seal is about 40% heavier than a male northern elephant seal (Mirounga angustirostris), more than twice as heavy as a male walrus (Odobenus rosmarus), and six to seven times heavier than the largest living terrestrial carnivorans, the polar bear (Ursus maritimus) and the Kodiak bear (Ursus arctos middendorffi).
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