National Geographic News
From a series of fossil discoveries in recent years, scientists have been expanding the picture of dinosaurs to include creatures that apparently sported tufts of primitive feathers. On Wednesday, the American Museum of Natural History in New York City unveiled what observers say is a "remarkable" specimen showing a small dinosaur that had a feathered covering from head to foot.
The fossilized skeleton, which is on loan from the National Geological Museum of China, is embedded in two mirror slabs of rocks estimated to be 130 million years old. It was unearthed last spring by farmers digging in Liaoning Province in northeastern China.
Covered by lakes and active volcanoes millions of years ago, the region has yielded a treasure trove of fossils over the past decade that are unusually well preserved because the animal remains were buried in the lake bottom's fine sediment of volanic ash and muck. The anatomical details in the new specimen are so well etched that the scientists who analyzed it could discern a herringbone pattern in some of the creature's primitive feathers and even observe how they were attached.
"I've seen the specimen and other feathered dinosaur fossils, and this one is a visually spectacular specimen with a halo of feathers," said James Clark, an associate professor of biology at George Washington University. "It's well preserved and amazinga small dinosaur surrounded by fur."
Clark said the new fossil is important because it offers far more complete and compelling evidence of "feathered dinosaurs" than most of the other similar specimens that have turned up in recent years, which have shown only patches of feathery fibers.
The team of U.S. and Chinese scientists who describe the find in this week's issue of the journal Nature say the fossilized creature belonged to a group of small, fleet-footed dinosaurs known as dromaeosaurs, which are the most closely related dinosaurs to modern-day birds.
"We're pretty confident it's a dromaeosaurus," said Mark Norell, chairman of the division of paleontology at the American Museum of Natural History. The discovery is part of a long-time research collaboration by Norell and Ji Qiang of the Chinese Academy of Geological Sciences.
Norell said the scientists based their conclusion on the presence of several anatomical features that are unique to dromaeosaurs, including a hyper-extendable curved claw on the middle toe and stiffening rods in the tail.
Dromaeosaurs are a subgroup of a dinosaur class known as advanced theropods, whose members included the well-known predator Tyrannosaurus rex.
Norell said the new fossil and similar evidence of feathered dinosaurs acquired in the past decade is "radically" altering common ideas about the nature of dinosaurs such as theropods. "We've experienced dramatic changes in the way we view dinosaurs, going from scaly Godzilla lizards to weird birds," he said.
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