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Blobrana


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Polar bear evolution
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Polar bear evolution tracked climate change, new DNA study suggests

An analysis of newly sequenced polar bear genomes is providing important clues about the species' evolution, suggesting that climate change and genetic exchange with brown bears helped create the polar bear as we know it today. The international study, led by researchers at Penn State and the University at Buffalo, found evidence that the size of the polar bear population fluctuated with key climatic events over the past 1 million years, growing during periods of cooling and shrinking in warmer times.
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Blobrana


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Polar bear
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  DNA reveals polar bear's ancient origins

The polar bear is much older than previously thought, according to new genetic evidence.
DNA studies suggest the Arctic predator split from its ancestor, the brown bear, about 600,000 years ago.
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Blobrana


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Polar bears have maternal Irish brown bear ancestors

The maternal ancestors of modern polar bears were from Ireland, according to a DNA study of ancient brown bear bones.
Scientists in the UK, Ireland and the US analysed the teeth and skeletons of 17 brown bears that were found at eight cave sites across Ireland.
The new research has been reported in the latest edition of Current Biology.
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Blobrana


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Nowadays they spend most of their time on Arctic ice floes but 18,000 years ago polar bears may have lived in the Scottish Highlands.
Why the world's largest carnivore was there, what it fed on and how different it was from its modern descendants are questions a study is intended to answer.
Scientists hope to unlock secrets in the DNA of what are believed to be the only polar bear remains found in Britain.
The skull, of which only half survives, was found at Inchnadamph in Sutherland in 1927 by archaeologists looking for evidence of Stone Age human habitation. It was first thought to be that of a cave bear and then a brown bear.
It has been in the National Museum of Scotland in Edinburgh since the 1950s.

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Blobrana


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What may be the oldest known remains of a polar bear have been uncovered on the Svalbard archipelago in the Arctic.
The jawbone was pulled from sediments that suggest the specimen is perhaps 110,000 or 130,000 years old.
Professor Olafur Ingolfsson from the University of Iceland says tests show it was an adult, possibly a female.
The find is a surprise because polar bears are a relatively new species, with one study claiming they evolved less than 100,000 years ago.

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