A Sino-American team of palaeontologists has unearthed the fossilized remains of an ancient flying mammal. The specimen was found in Ningcheng County, Inner Mongolia, China. The animal, which lived during the late Jurassic or early Cretaceous (125 million years ago), has been named Volaticotherium antiquus (meaning ‘ancient flying beast’).
This squirrel-like animal was between 12-14 cm long and weighed approximately 70 grams. It had sharp, pointed teeth which were probably used for eating insects. The large brown oval-shaped structure in the image below is an impression of a patagium, or flying membrane, left in the rock in which the fossil was found. It was covered in dense hair and supported by an elongated tail and limb bones.
In extant animals such as the flying squirrel, the patagium is an adaptation to gliding flight; it extends from the wrist to the ankle, and acts as an airfoil, supporting the weight of the animal as it jumps from trees and extends its limbs. The small body mass and large patagium of V. antiquus suggests that it was a very agile glider; it is likely to have led a nocturnal, tree-dwelling existence, and used its aerial skills to move from tree to tree but not to capture prey.
Phylogenetic analysis has led to the conclusion that V. antiquus represents an entirely new order of mammals. It predates other known gliding mammals by at least 70 million years; previously, there had been no evidence of flying mammals before 51 million years ago. This shows that V. antiquus took to the skies at around the same time, or perhaps before, birds did.