for National Geographic News
An extraordinarily bizarre-looking species of dinosaur has been discovered in China's Gobi desert that could unlock clues as to how an unusual family of vegetarian dinos evolved, scientists say.
The newfound species belonged to a group of large dinosaurs called therizinosaurs, relatives of meat-eating theropods like Tyrannosaurus rex.
"These are without doubt some of the strangest dinosaurs ever found," said Matt Lamanna, a paleontologist at the Carnegie Museum of Natural History in Pittsburgh, Pennsylvania.
"They looked kind of like a gigantic plucked turkey."
The earliest known therizinosaurs date to 125 million years ago and have been found in eastern China and western North America.
Scientists are unsure where these dinosaurs evolved first, but they likely migrated between the continents on land bridges that periodically appeared millions of years ago.
The new specimen dates to about 115 million years ago and is the oldest large therizinosaur known.
The earliest large therizinosaur known from North America is Nothronychus, which dates to about 90 million years ago.
Named Suzhousaurus megatherioides, the new Gobi dino was about 22 feet (6.7 meters) long, 7 feet (2.1 meters) tall at the hips, and weighed between 1 and 2 tons.
The new fossil, discovered in 2002 but named only now, indicates that Asian therizinosaurs reached their large size before their North American counterparts did.
"It suggests that regardless of which continent they originated in, [therizinosaurs] got big in Asia before they got big in North America," Lamanna said.
(Read related story: "'Missing Link' Dinosaur Discovered in Montana" [October 2, 2007].)
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