Fossil evidence of missing link in the origin of seals, sea lions, walruses found in Canad...(e in On the Origin of Species by the Mea...)

Date:4/22/2009

e in On the Origin of Species by the Means of Natural Selection, "A strictly terrestrial animal, by occasionally hunting for food in shallow water, then in streams or lakes, might at last be converted in an animal so thoroughly aquatic as to brace the open ocean."

"The find suggests that pinnipeds went through a freshwater phase in their evolution. It also provides us with a glimpse of what pinnipeds looked like before they had flippers," says Natalia Rybczynski, leader of the field expedition.

The animal is described as having a long tail, and fore-limbs comparatively proportionate to modern carnivorous land animals as opposed to pinnipeds. It is the first mammalian carnivore found at the site. Other fossils found include two taxa of freshwater fishes, one bird, and four mammalian taxa: shrew, rabbit, rhinoceros, and small artiodactyl (small short-legged herbivores, ancestors to modern giraffes and deer).

The earliest well-represented pinniped, Enaliarctosa marine form with flippershas been found on northern Pacific shores of North America. It had been theorized for some time that pinniped evolution had been centered around the Arctic; the discovery of Puijila adds credence to this theory.

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Contact: Laura Sutin lsutin@mus-nature.ca 613-566-7493 Carnegie Museum of Natural History Source:Eurekalert

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