Seals are a widely distributed and diverse clade of carnivorous, fin-footed, semiaquatic marine mammals. They comprise the following extant families:
– the walrus
– the eared seals: sea lions and fur seals
– the earless seals or true seals
They spend most of their lives in the water, but come ashore to mate, give birth, molt or escape from predators, like sharks and killer whales. They feed largely on fish and marine invertebrates; but a few, like the leopard seal, feed on large vertebrates, such as penguins and other seals.
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