A tiny ancient primate the size of a mouse may shed new light on the origin of the species, BBC reported.
Scientists named the newly discovered fossil Archicebus, which means "ancient monkey." The fossil is 55 million years old and was found in China.
The creature's age puts it right at the bottom of the evolutionary chain of primates.
"We are all very curious about the ancestors of primates, including those of human beings," Dr. Xijun Ni from the Chinese Academy of Sciences, Beijing, China, said. "From this almost complete skeleton, we can conclude that our ancestors were a kind of very small animal. It was very active and agile; and it lived in the trees and fed on insects."
The fossil was sent to the European Synchrotron Radiation Facility (ESRF), in Grenoble, France. The specimen will be X-rayed to look for more of the skeletal structure within the rock that engulfs it.
"There's no way you can prepare the fossil any better to see its features because you would end up with a powder; it's extremely fragile," said the ESRF's Dr Paul Tafforeau. "But when you scan it with synchrotron light, you can virtually extract the bones without touching them. This gives you access to the general anatomy and we can achieve very high resolution."
The small primates walked the Earth shortly after the extinction of the dinosaurs. The imaging should give researchers a picture of what the first primates looked like.
"At this time, 55 million years ago, the Earth was a jungle planet," said Nature editor Dr. Henry Gee. "The whole Earth was covered with tropical jungle - full of trees for little scampery things to climb up and down on. It was an ideal time for primates to be evolving."
Researchers believe that the creatures ate insects, it had large eye sockets that gave it excellent daytime sight for hunting.
"The heel, and the foot in general, was one of the most shocking parts of the anatomy of this fossil when we first saw it; because, frankly, the foot of this fossil primate looks like a small monkey, specifically like a marmoset" said Dr. Chris Beard from the Carnegie Museum of Natural History, Pittsburgh.
