Mammals started flying when birds did.The first gliding mammal winged through forests at least 70 million years earlier than scientists had previously presumed, a new fossil shows. The specimen dates from about 150 million years ago, during the time when birds were developing flight. "This changes our view about the early evolution of mammals __FORCETOC__ The evolution of mammals from synapsids (mammal-like reptiles) was a gradual process which took approximately 70 million years, from the mid-Permian to the mid-Jurassic, and by the mid-Triassic there were many species that looked like mammals. ," says Jin Meng of the American Museum of Natural History American Museum of Natural History, incorporated in New York City in 1869 to promote the study of natural science and related subjects. Buildings on its present site were opened in 1877. in New York City New York City: see New York, city. New York City City (pop., 2000: 8,008,278), southeastern New York, at the mouth of the Hudson River. The largest city in the U.S. . Scientists had proposed that mammals from that period "lived in the shadow of dinosaurs and were relatively primitive," Meng says. He and his colleagues report the finding in the Dec. 14 Nature. Farmers found the new fossil in Inner Mongolia Inner Mongolia Chinese Nei Mongol or Nei-meng-ku Autonomous region (pop., 2002 est.: 23,790,000), China. Stretching some 1,800 mi (2,900 km) across north-northeastern China, it has an area of 454,600 sq mi (1,177,500 sq km); its capital is Hohhot. last year. The creature weighed roughly a pound and was similar in shape to today's flying squirrel flying squirrel, name for certain nocturnal tree squirrels adapted for gliding; they do not actually fly. Most are found in Asia, but one species of the genus Pteromys extends into SE Europe and the two species of Glaucomys are found in North America. . It soared on skin flaps stretching from its extra long arms to its gangly gan·gly adj. gan·gli·er, gan·gli·est Gangling. [Alteration of gangling.] Adj. 1. legs, which were covered with dense hair. The animal is one of the oldest in the fossil record to show fur, and it's so different from any other known mammal that the researchers had to create a new genus, family, and order for it. The team named the creature Volaticotherium antiquus, or "ancient gliding beast." Since V. antiquus was so light and had large membranes for gliding, it must have swooped and turned nimbly. It steered with a long, stiff tail that acted as a rudder, say the researchers. The creature has no known descendants or ancestors. Meng speculates that now that researchers know what to look for, they may soon discover some V. antiquus relatives.--J.J.R. |
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