Discoveries made in Canada’s Artic explain just how seals went from land-based to marine-based animals. The fossil of an unknown web-footed carnivore was recently uncovered by Natalia Rybczynski. The animal has been found to be very similar to an otter, however it has a skull that more closely resembles a seal’s. The animal has been dubbed Puijila Darwin. The word Puijila refers to a young seal. The animal also bears Darwin’s name because it exemplifies what he wrote about in the Origin of Species. “A strictly terrestrial animal, by occasionally hunting for food in shallow water, then in streams or lakes, might at last be converted into an animal so thoroughly aquatic as to brave the open ocean.” Puijila is a part of the pinniped group which also includes seals, sea lions, and walruses. It was found to be living near fresh water lakes over 20 million years ago. It is an example of a transitional animal since it did not have flippers like modern pinnipeds, but had webbed feet. It was not well designed for living in water, the fossil suggests that Puijila swam using its four legs unlike modern seals and otters. Both animals depend on only their hind legs to swim. There is evidence that Puijila Darwin lived at the same time as the Enaliarctos, which was the earliest pinniped known prior to the discovery of Puijila. This means that though a new body plan “refined for superior swimming” had emerged, Puijila Darwin had not yet died out. The discovery has been extremely important to understanding how pinnipeds evolved into what they are today.
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