Dubbed Kretzoiarctos beatrix, the 11-million-year-old species was previously named Agriarctos beatrix based on a few fossil teeth found at a paleontological site near Zaragoza, Spain (map). Agriarctos is an extinct genus of European bear and a possible panda ancestor that lived eight to nine million years ago. (Read about the previous research.)
Earlier this year, scientists found a piece of A. beatrix's jaw, allowing them to compare it with that of another ancient Agriarctos bear from Hungary. In doing so, the team determined that A. beatrix is actually its own genus, which they called Kretzoiarctos.
The newly named K. beatrix pushes back the origin of giant pandas by a few million years, making it the oldest recorded giant panda relative, said study leader Juan Abella, a paleobiologist at the Museo Nacional de Ciencias Naturales in Madrid, Spain.
"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 in May.
New Bear Was Panda-Like?
K. beatrix likely shared some similarities with today's giant panda.
For one, says Abella, the newfound jaw fragment shows the animal was likely an omnivore that fed on tough plants, like modern-day pandas. Also like them, and like most existing species of small bears, K. beatrix was probably a great climber. According to Abella, it would have had to scramble up trees to escape big predators of the day—such as extinct, doglike carnivores called bear-dogs—in the forests of what's now Spain.
An Epic Trek?
It's still unclear how panda ancestors made the epic trek from Europe to China.
Previous research suggests bears generally can migrate easily if the climate is mild enough, Abella said. Eleven million years ago, southwestern Europe was warm and humid-good conditions for starting out, he said.
The bears likely migrated mostly on land. One potential barrier—an ancient European sea called Parathetys—was already shrinking during the Middle Miocene, when K. beatrix lived, said Abella.
As for whether K. beatrix made it to China, "We don't really know, but no fossil remains of this species have been found outside Spain."
Whatever its history, the new research shows that K. beatrix was not your average bear.
The oldest panda relative study was published November 14 in the journal PLoS ONE.