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Chinese scientists have claimed that a squirrel-like mammal that lived 125 million years ago appears to have discovered gliding flight at about the same time, or even earlier, than the first birds.

Researchers said the extinct mammal, called Volaticotherium antiquus, which means "ancient flying beast", had features adapted for life in trees. No other mammals from the Mesozoic period -- the period in which flying reptiles, birds, and flowering plants developed and dinosaurs bestrode the earth -- had such characteristics.

The fossil, found in Daohugou, Ningcheng county in north China's Inner Mongolia Autonomous Region, pushes back the first record of gliding flight for mammals by 70 million years, according to the findings of a group of Chinese researchers from the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences.

"This discovery rolls back the earliest record of gliding flight for mammals by at least 70 million years and demonstrates that mammals were diverse in their locomotor strategies and life styles," writes the research group in the study report.

"Mammals experimented with aerial habits at about the same time as, if not earlier than, birds," said leading author Jin Meng and co-authors Yaoming Hu, Yuanqing Wang, Xiaolin Wang and Chuankui Li.

Their study is published in Thursday's issue of the prestigious British journal Nature. The mammal was about 12 to 14 centimeters long and weighed 70 grams.

Its teeth were made for eating insects and it had a big furry patagium -- a flying membrane -- for gliding flight. The patagium was joined to a long tail and limbs, according to the scientists.

The animal lived on a diet of small insects which it probably caught while clambering through the tree tops. Its agility in the air was probably not good enough to be able to catch its prey in flight, as most insectivorous bats do, according to the scientists.

It was most probably nocturnal, not only because small Mesozoic mammals are generally thought to be nocturnal, but also because gliding mammals are predominantly arboreal and nocturnal, the study says.

The earliest identified gliding mammal was a 30-million-year-old extinct rodent. The first known modern bat, which is capable of powered flight, dates to 51 million years ago. It is assumed that proto-bats were probably gliding much earlier but no fossil records of them have been found.

(Xinhua News Agency December 16, 2006)