Seals enter the water
A bear-like carnivore on the north Pacific coast becomes the ancestor of every seal, sea lion and walrus.
- When
- —
- Duration
- 1 million years
- Known to
- ± 1 million years
- Era
- Oligocene, Cenozoic
Enaliarctos, from the latest Oligocene of the North Pacific, is the earliest well-known pinniped: a metre-and-a-half carnivoran with flippers on all four limbs, still able to move on land, and with teeth suited to catching and cutting fish rather than swallowing them whole. Pinnipeds are the fourth major mammal lineage to return to the sea after whales, sirenians and desmostylians, and unlike whales they never fully leave land, because they still give birth there.