Sea lion Temporal range: Late Oligocene-Holocene |
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California sea lion (Zalophus californianus) | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Carnivora |
Suborder: | Caniformia |
Clade: | Pinnipedia |
Family: | Otariidae |
Subfamily: | Otariinae |
Genera | |
Eumetopias
Neophoca
Otaria
Phocarctos
Zalophus
Sea lions are sea mammals characterized by external ear flaps, long foreflippers, the ability to walk on all fours, and short, thick hair, big chest and belly. Together with the fur seals, they comprise the family Otariidae, eared seals, which contains six extant and one extinct species (the Japanese sea lion) in five genera. Their range extends from the subarctic to tropical waters of the global ocean in both the Northern and Southern Hemispheres, with the notable exception of the northern Atlantic Ocean. They have an average lifespan of 20–30 years. A male California sea lion weighs on average about 300 kg (660 lb) and is about 8 ft (2.4 m) long, while the female sea lion weighs 100 kg (220 lb) and is 6 ft (1.8 m) long. The largest sea lion is Steller's sea lion, which can weigh 1,000 kg (2,200 lb) and grow to a length of 10 ft (3.0 m). Sea lions consume large quantities of food at a time and are known to eat about 5–8% of their body weight (about 15–35 lb (6.8–15.9 kg)) at a single feeding.
Together with the fur seals, they constitute the family Otariidae, collectively known as eared seals. Until recently, sea lions were grouped under a single subfamily called Otariinae, whereas fur seals were grouped in the subfamily Arcocephalinae. This division was based on the most prominent common feature shared by the fur seals and absent in the sea lions, namely the dense underfur characteristic of the former. Recent genetic evidence, however, strongly suggests Callorhinus, the genus of the northern fur seal, is more closely related to some sea lion species than to the other fur seal genus, Arctocephalus. Therefore, the fur seal/sea lion subfamily distinction has been eliminated from many taxonomies.