Tuesday, 15 May 2012

Prehistoric "Panda" Found in Spain—Giant Panda Has European Roots?


Small tree-climber is oldest known panda relative.

An illustration of a newly discovered extinct species that was related to modern-day pandas.
With only teeth to go on, scientists have reportedly identified a giant panda ancestor: A. beatrix.
A prehistoric relative of the giant panda has been discovered in Spain, a new study says—which suggests that the charismatic Chinese bears might have originated in Europe.
The 11-million-year-old species, dubbed Agriarctos beatrix, lived in humid forests in what's now Spain, according to scientists who recently found the animal's fossil teeth near the city of Zaragoza (map).
The teeth give paleontologists a lot of information about a species, according to study leader Juan Abella, a paleobiologist at the Museo Nacional de Ciencias Naturales in Madrid, Spain.
"For example, all bear [teeth] have a series of characters that tell us that they are bears. And the same thing happens with dogs, cats, deer, or other vertebrate groups," Abella said via email.
After analyzing the fossil teeth, he added, the researchers "concluded that they belong to the bear family, and more precisely to the giant panda's subfamily."
And the subfamily resemblance may have been striking—Abella and colleagues speculate that the bear had panda-like patterns, because most existing species in the family also have the characteristic dark and white patches.
New Bear Points to European Panda Origins?
But A. beatrix was not your average bear.
For one thing, the 130-pound (60-kilogram) animal was even smaller the smallest modern-day bear species, the sun bear—so it probably wasn't exactly the top hunter of prehistoric Europe.
Like current pandas and small bears, the newfound species may have scrambled up trees to escape big predators of the day, such as bear dogs—extinct, doglike carnivores—and saber-toothed, feline-like creatures calledBarbourofelidae, the team speculated.
For another thing, A. beatrix is the oldest known species in the subfamily Ailuropodinae, which includes the giant panda.
"Therefore, the origin of this group is not located in China, where the [giant panda] species lives, but in the warm and humid regions of [southwestern] Europe," Abella said.
But Blaine Schubert, a paleontologist at East Tennessee State University who has studied prehistoric bears, said such a claim "seems fairly speculative."
The new study "doesn't say that this is evidence that panda bears may have originated in Europe," said Schubert, who was not involved in the study.
"Further, even if this new fossil is a relative of modern pandas, it doesn't mean that pandas originated there. I would not suggest this based on the evidence and I wouldn't want to make a claim like that without a lot more evidence."
Giant Panda Ancestors Trekked to China?
If giant panda ancestors did come from Spain, how did they get to China?
Previous research suggests bears generally are "able to disperse quite easily if the environmental conditions were favorable for them," Abella said. At the time, southwestern Europe was warm and humid—good conditions for starting out, he said.
The bears also likely migrated mostly on land—one potential barrier, an ancient European sea called Parathetys, was already shrinking by A. beatrix's time, he said.
As for whether A. beatrix itself made it to China, "we don't really know. But no fossil remains of this species have been found outside Spain."
Abella next hopes to unearth an A. beatrix skeleton, which would reveal more about the how the bear lived and moved. 
It's unknown whether such a skeleton exists, but the team working with theInstitut CatalĂ  de Paleontologia in Barcelona to excavate "very rich and interesting" fossil beds, Abella said. These fossil beds could conceivably contain A. beatrix remains, since the beds are about as old as those A. beatrixteeth.

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