This was the midway period between the warmer Paleogene and cooler Neogene period. The initial fossil of the Seal has been found is Puijila darwini. This is about 23 million years ago. Pujilla had weighty limbs, analytic of upright movement on land. These types of animals had flattened phalanges, indicating that they were perhaps webbed, but not yet flippers. The discovery of Pujilla Seal in northern Canada strongly suggests that Seal originated in the Arctic.
The otter like mustelid Potamotherium may really represent an even earlier phase in the evolution of Seal. Another (more advanced) early Seal is Enaliarctos, which lived 24 to 22 million years ago. It is believed that these types of animals were good swimmer. They were able to move on land as well as in water. They were more like an otter than like modern Seal. There has been longstanding debate as to whether walruses diverged from an ordinary otariid phocid ancestor, or whether the phocids diverged before a common otariid odobenid ancestor. The most new evidence suggests that the latter hypothesis is more probable.
Seals are classically sleek bodied. They barrel shaped, and can be rather large. The bodies of the Seal are well modified to the aquatic habitat where they spend most of their lives. Their limbs have evolved into short, wide, flat flippers. The smallest of them, the Galapagos Fur Seal weighs about 30 kg.
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Seal also called fin footed mammals are a broadly distributed and diverse group of semi aquatic marine mammals. They belong to the families of Odobenidae (the walrus), Otariidae and Phocidae. Seal are formerly classified as a separate biological suborder. Seals are now occasionally considered a superfamily within Caniformia, a suborder in the Carnivora order. Recent molecular evidence suggests that seals evolved from a bear like ancestor about 23 million years ago during the late Oligocene period.
Seal also called fin footed mammals are a broadly distributed and diverse group of semi aquatic marine mammals. They belong to the families of Odobenidae (the walrus), Otariidae and Phocidae. Seal are formerly classified as a separate biological suborder. Seals are now occasionally considered a superfamily within Caniformia, a suborder in the Carnivora order. Recent molecular evidence suggests that seals evolved from a bear like ancestor about 23 million years ago during the late Oligocene period.
