Rare polar bear fossil discovered in Norway in 2004 has become a treasure of information about age and the evolutionary origins of the species, now highly threatened by global warming.
A study by researchers at Pennsylvania State University, the University of Buffalo, of Oslo, and other institutions, is putting in place the key pieces of the puzzle of the evolutionary history of polar bears and grizzly bears, including response to past climate changes.
The results of this study confirm that the polar bear is a species evolutionarily young man who was separated from brown bears about 150,000 years ago and evolved very rapidly during the late Pleistocene, probably adapted to the opening of new habitats and food sources in response to climate change just before the last interglacial period.
Very few fossils have been found polar bears, which has led to a wide range of estimates of when and how exactly evolved. The fact that these bears live in ice, which often makes their bodies fall to the bottom of the ocean.
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