Scientists Identify Strange Fossils of Ferocious 'Beardogs' in Texas
A group of researchers have identified the remains of a strange animal that once roamed North America about 40 millions years ago. Neither a dog nor a bear, "beardogs" belong to a strange extinct species that were considered as ferocious predators in their ecosystem.
According to the study published in the journal Royal Society Open Science, the fossils unearthed by Chicago's Field Museum were first thought to be generic carnivorans. The two fossilized jawbones, named Gustafsonia and Angelarctocyon, reveal that they belong to a creature the size of a Chihuahua.
However, despite its Chihuahua size when it first appeared, Science Magazine points out that bear dogs evolved over time, becoming a top predator millions of years ago. The first species of bear dogs were relatively light and small in size, but as evolution plays out, the bear dogs grew to the size of foxes, coyotes and even bears.
Amphicyonids or bear dogs got its name from its physical appearance, which resembles that of a dog and a bear. These meat-eaters thrived in North America, Asia and Europe 40 millions years ago and could be distant relatives of bears and dogs, says vertebrate paleontologist Susumu Tomiya from The Field Museum of National History.
"Our research pinpoints the southwestern US as a key region in understanding the diversification and proliferation of this once successful group of predators prior to their extinction millions of years ago," said co-author Jack Tseng, PhD.
Back in 1986 when the fossils were discovered in Texas, scientists classified them under the genus Miacis, a "miscellaneous" category for ancient carnivores. However, Tseng and his team have moved this strange creature into a new genus.
"It's a kind of 'trashbin' genus, when the question is, well, what else could it be? Now we've taken these fossils out of the trashbin and put them at the base of the beardog tree," Tseng explained in a press release. "We're not saying we've solved where they fit on the tree of life, but it's the most progress that's been made in quite awhile. Our work provides a clearer connection between the rest of the beardog family and their evolutionary roots."