Pinnipeds, colloquially known as seals, are a widely distributed and diverse clade of fin-footed, semiaquatic marine mammals. They comprise the extant families Odobenidae (whose only living member is the walrus), Otariidae (the eared seals: sea lions and fur seals), and Phocidae (the earless, or true seals). Seals range in size from the 1 m (3 ft 3 in) and 45 kg (99 lb) Baikal seal to the 5 m (16 ft) and 3,200 kg (7,100 lb) southern elephant seal, which is also the largest carnivoran.[b] Several species exhibit sexual dimorphism. They have streamlined bodies and four limbs that are modified into flippers.