Enaliarctos
Group Placental mammals
Date Early Miocene
Size 1.5 m. long
Location USA
Enaliarctos is the earliest-known relative of the pinnipeds (seals, sea lion, and walruses). Its fossils have been found in Early Miocene rock in California and Oregon, USA. Like later seals and sea lions, Enaliarctors’s limbs were modified into crude flippers, although they were not as highly specialized as those of modern pinnipeds. Enaliarctor used both front and hind limbs for swimming; modern sea lions use just their forelimbs for swimming, and all four flippers to move on land, while modern seals use their hind flippers for swimming and are less mobile on land. Although it had large eyes, sensitive whiskers, and good underwater hearing, like its living descendants, Enaliarctos’s teeth were more primitive and resembled those of its bear-like ancestors. It ate fish but, unlike seals, could not eat its catch while swimming-instead it had to drag its prey to the shore to tear it apart.