Pinnipeds , (from
Latin pinna "fin" and
pes, pedis "foot")
commonly known as
seals, are a widely
distributed and diverse
clade of
carnivorous, 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 seals, or true seals). There are 33 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 evidence supports them as a
monophyletic lineage (descended from one ancestral line). Pinnipeds belong to the order
Carnivora and their closest living relatives are
bears and
musteloids (
weasels,
raccoons,
skunks and
red pandas), having diverged about 50 million years ago.
