Recently discovered fossils in Tibet show that big cats may have originally evolved in Asia. Previously, all of the fossil evidence suggested beginnings in Africa. This announcement comes from lead author Z. Jack Tseng from the American Museum of Natural History and was published today in Proceedings of the Royal Society B.
Before this discovery, the oldest fossils of cats from the Panthera genus were around 3.8 millions of years old and located in Africa. Molecular analysis however, determined that the big cats came from Asia nearly 11 million years ago. Scientists were at a loss, as there was no way to reconcile those two facts. Older fossils of large cats are quite rare, meaning the early parts of their phylogenetic tree are largely incomplete.
Recently, a few teeth, a portion of a jawbone, and part of a skull were discovered in Tibet. They have been dated as 4.1-5.95 million years old, which supports the molecular data and reconciles the fossils found in Africa. The newly discovered cat has been named Panthera blytheae, and is believed to be a relative of the modern day snow leopard which lives in the same location. At the time P. blytheae lived, it probably hunted along the rocky cliffs in the Himalayas, just as snow leopards do today.
These fossils have helped clarify some parts of the early phylogenetic tree and have even given new insight as to when the Panthera genus (lions, tigers, panthers) first diverged from Neofelis (clouded leopards). The new evidence suggests the split occurred in the early Miocene 16.5 million years ago, which is 7 million years earlier than previously believed.
The newly discovered P. blytheae fossils may be the oldest that have been found so far, but there are still many more questions about what cats came before it. The Felidae family is estimated to be 25 million years old and there are still many more gaps waiting to be filled in.
