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RE: Newfound Dinosaur a Transitional Creature
OOPS - Didn't mean to 'dis' Scott Sampson. Kudos to him too!
From: Allan Edels <email@example.com>
Subject: Newfound Dinosaur a Transitional Creature
Date: Wed, 04 May 2005 13:49:50 -0400
From the AP, via Yahoo:
Newfound Dinosaur a Transitional Creature
By MALCOLM RITTER, AP Science Writer
6 minutes ago
Scientists have caught a dinosaur in the act of evolving from meat-eater to
The two-legged, feathered creature ate plants, but its bones show that the
transition from its carnivorous ancestors was still in progress.
All plant-eating dinosaurs were ultimately descended from a meat-eater, and
switchovers to plant-eating occurred several times. The newly discovered
species, which lived 125 million years ago in what is now Utah, could help
scientists understand details of how the changeovers took place.
It's "our first really good case of a dinosaur in the midst of shifting
from the meat-eating body to a plant-eating one," said an expert not
involved in the discovery, Thomas R. Holtz Jr. of the University of
"It's definitely eating a substantial amount of plants, (but) we still see
the original imprint of meat-eating upon it."
The creature, with 5-inch claws on its outsized hands, measured some 12
feet from its snout to the tip of its long skinny tail. It stood just over
3 feet tall at the hip and could apparently reach about five feet off the
ground with its long neck to munch leaves or fruit, said Utah state
paleontologist James Kirkland.
He describes the creature in Thursday's issue of the British journal Nature
with Lindsay Zanno and Scott Sampson of the Utah Museum of Natural History
at the University of Utah, among others.
They dubbed it Falcarius utahensis. Bones from hundreds or maybe thousands
of these dinosaurs were discovered at a two-acre dig site in east-central
Utah, south of the town of Green River. Nobody knows why they gathered
there or what killed them, Kirkland said.
But analysis revealed that Falcarius was the earliest known member of a
bizarre-looking group of plant-eaters called therizinosaurs (pronounced
THAY-rih-ZY-no-sores.) Found mostly in Asia, the barrel-bodied creatures
waddled upright like Godzilla or "a pot-bellied bear," Kirkland said.
Falcarius, very early in its evolution into the therizinosaur body type,
retained the rather horizontal posture and built-for-speed legs of its
meat-eating ancestors. But it had already lost the flattened and serrated
teeth used to tear meat and acquired the smaller, more densely packed teeth
of a vegetarian, Zanno said.
It also showed some change toward the larger gut needed to digest plant
material rather than meat, as well as a lengthened neck and smaller head
associated with eating plants, she said.
Holtz said Falcarius still had fairly slender proportions overall rather
than the barrel body of later therizinosaurs. "This one could probably move
fairly quickly," he said, whereas its more evolved relatives "would have
had problems hunting things faster than a tree."
Kirkland and Zanno said they suspect Falcarius probably ate some meat in
addition to plants.
"I wouldn't doubt this thing would eat a lizard or two in a pinch,"
Congrats to Jim and Lindsay (and to Tom for being a prime source [as an
uninvolved scientist] for the article :-)