A Creature to Make T. Rex Tremble
By MALCOLM W. BROWNE
Published: July 21, 1992
DESPITE the growing bitterness of clashes between rival paleontologists and the Federal Government over collecting rights, three important fossil discoveries were reported last week, including that of a dinosaur billed as the deadliest land creature the earth has seen.
Scientists have studied the bones of several specimens of the species, which they have named "utahraptor." The animal, nicknamed "su perslash er," weigh ed about one ton, reached a length of about 20 feet, was a swift runner and was armed with a 15-inch slashing claw that stood upright and apart from the other claws on each hind foot.
The animal's forelegs had large paws tipped with powerful claws suitable for grasping prey while the dinosaur kicked its victim with its sickle-clawed hind feet. The utahraptor was described by its finders as a "Ginsu-knife-pawed kick-boxer" that could disembowel a much larger dinosaur with a single kick. This killer probably hunted in packs, they say.
The fearsome tyrannosaur, which lived some 60 million years later than the newly discovered utahraptor, is traditionally considered the most terrible of all land predators. But the tyrannosaur was probably much slower and less nimble than the slasher, its discoverers say, and Tyrannosaurus rex lacked the upright slashing claw that must have made utahraptor the terror of the early Cretaceous period, about 125 million years ago.
The first claw bone of a utahraptor was unearthed last October in a quarry in eastern Utah by Carl Limoni, a laboratory staff member of the College of Eastern Utah. After the bones of several individuals were discovered, Dr. James I. Kirkland of the Dinamation International Society identified the dinosaur as belonging to the dromaeosaurid family of dinosaurs, which includes the much smaller deinonychus (a name meaning "terrible claw"), an agile, speedy creature about the size of a wolf.
The discovery of the deinonychus in 1964 by Dr. John H. Ostrom of Yale University helped change the traditional view of dinosaurs as sluggish, slow-moving beasts. Scientists found that deinonychus was capable of rapid movements and attacks coordinated by large brains, characteristics similar to those of birds. This supported a theory that modern birds are directly descended from dinosaurs, as well as a theory that many if not all dinosaurs were warm-blooded.
The Dinamation International Society, which identified the new species, is a nonprofit foundation established by the Dinamation International Corporation, which builds and displays anatomically accurate animated replicas of dinosaurs. The utahraptor bones are destined for display at the College of Eastern Utah Museum in Price. Mammal-Like Reptile
In another major find, reported last week in the British journal Nature, scientists announced the discovery of a mammal-like reptile of a kind that had been thought to have died out around 160 million years ago, but which apparently lived on to about 55 million years ago, long after the demise of the dinosaurs.
One of the scientists who identified the fossil, Dr. David W. Krause of the State University of New York at Stony Brook, said the discovery was nearly as surprising as that of the coelacanth, a primitive fish formerly believed to have become extinct during the age of dinosaurs. To the astonishment of paleontologists, a live coelacanth was discovered in 1938, and several score of these "living fossils" have been found since.
The newly discovered mammal-like reptile was found by Dr. Richard C. Fox of the University of Alberta in Edmonton while sifting through debris at an excavation near Cochrane, Alberta.
Because it seems to have lived at a time very distant from that of its previously known relatives, the animal was given the scientific name Chronoperates paradoxus, or "time wanderer contrary to expectations." From the animal's diminutive teeth and sections of jaw bones the scientists concluded that it was about the size of a modern shrew and was clearly related to much earlier mammal-like reptiles belonging to the group therapsids.
Therapsids, sometimes called protomammals, are believed to have been the ancestors of true mammals, and may, therefore, have been distant ancestors of human beings. Not So Formidable?
A third discovery reported last week was made by paleontologists headed by one of the scientists involved in the fossil-rights dispute, Dr. Kraig Derstler of the University of New Orleans.
Working at a site on private property near Lusk, Wyo., Dr. Derstler's team has uncovered part of the skeleton of a triceratops that exhibits evidence of having been attacked and perhaps killed and eaten by a tyrannosaur, a broken tooth of which was found among the bones. This is the first direct evidence that the formidable horned dinosaurs actually fell victim to tyrannosaurs, Dr. Derstler said.
In announcing the fossil discovery, Dr. Derstler, an opponent of what he regards as excessive government regulation of fossil collecting, took the opportunity to denounce the recent seizure of a tyrannosaur fossil by the Federal Bureau of Investigation from the Black Hills Institute of Geological Research, a commercial fossil dealer in Hill City, S.D. The seizure was ordered by Acting United States Attorney Kevin Schieffer, and Dr. Derstler poked fun at Mr. Schieffer by naming the tyrannosaur-gnawed fossil of the triceratops "Kevin."
Dr. Derstler remarked: "We've got a dinosaur that was trashed by Tyrannosaurus. We hope that Mr. Schieffer eventually meets a similar fate."
Drawings: Two utahraptors, or "superslashers," attacking a brachiosaurid. Superslashers weighed about a ton and could reach a length of about 20 feet. Each hind foot had a 15-inch upright slashing claw. (The New York Times; Illustration by Michael Rothman) (pg. C1); Scientists realized they had found a ferocious new type of dinosaur when they found this 9-inch bone, the core of a claw 15 inches long. The one-ton utahraptor used the claw to disembowel prey. (Dinamation International Society) (pg. C8)