 An artist's rendering of the first
flying mammal. [Xinhua]
 |
BEIJING -- 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.