From Science News:
Fossils push back origins of modern mammals
Common ancestor evolved over 200 million years ago
by Meghan Rosen
2:39pm, September 10, 2014
Modern mammals’ ancestors may have emerged millions of years earlier than scientists suspected — around the time the first dinosaurs roamed the Earth.
“That’s really, really old,” says paleontologist Robert Asher of the University of Cambridge, who was not involved with the work. Scientists had thought that the common ancestor of those animals originated sometime in the Jurassic, he says. “This is very exciting stuff.”
Xianshou songae is the name of the newly discovered dinosaur age mammal.