The oldest fossils of a previously unknown ancient leopard species are shaking the pantherine evolutionary tree, suggesting that big cats arose in Asia, not Africa, according to a new study.
Paleontologists led by the Natural History Museum of Los Angeles and the University of Southern California discovered the previously undescribed sister species to the modern snow leopard while on a 2010 expedition to Tibet. Seven specimens from three individuals range in age from 4.1 million to 5.9 million years old dialing back the clock on big cat evolution by as much as 2 million years, according to the paper, published online in Proceedings of the Royal Society B.
Panthera blytheae, named for the daughter of longtime museum benefactors Paul and Heather Haaga, was slightly smaller than the snow leopard and probably roamed the Tibetan plateau for several million years, dining on an ample supply of antelope, pika and blue sheep, according to paleontologist Zhijie Jack Tseng, lead author of the paper.
We think that the snow leopard and this new cat probably represent a new lineage that was adapted to the high elevation environment of the Tibetan plateau, said Tseng, a postdoctoral fellow at New Yorks American Museum of Natural History who conducted the work while he was a doctoral student at USC.
Big cats have presented serious problems for paleontologists. The ancient ambush hunters preferred habitat proved unproductive for fossilization, leaving a poor record of a sojourn on Earth that exceeded that of modern man by millions of years.
Modern genetic sleuthing based on living species suggests that big cats diverged from other cats about 11 million years ago, then radiated into multiple species lion, tiger, jaguar, leopard about 6 million years ago.
And thats the story that the molecular biologists would tell, Tseng said. If you only looked at the fossil, it would suggest Africa. If you only looked at DNA, it would suggest Asia. So there was no new material to reconcile this difference until now.
The team used the new fossils and other specimens to recalibrate the evolutionary tree and reconcile it with a DNA-based timeline. Although enormous gaps remain in the fossil record, the newly reconstructed tree lends weight to the theory that the cats arose and flourished in Asia.
We have the oldest but not the most primitive (species), which is interesting because it means that there are more primitive cats to be found in the fossil record that would be older than the one we have now, but just havent been found, Tseng said.