Oldest Fossil of Placental Mammal Is Discovered

It was about six inches long from head to tail, a furry, shrew-like tree-climber that ate insects and maybe worms, and probably hid out during the day to stay away from marauding dinosaurs.

This small creature lived 125 million years ago in northeast China. It is the oldest fossil of a placental mammal yet discovered. Scientists from Pittsburgh’s Carnegie Museum of Natural History who made the find have dubbed the creature Eomaia scansoria, or “climbing dawn mother.”

“This is a time period where we had not found any mammals at all,” said paleontologist John R. Wible, who led the Chinese/American team. “Until now, the oldest we had lived 115 million years ago, and all there was were jaws or teeth. This is an almost intact skeleton in articulation.”