Huge dinosaur pelvis discovered in Colorado.

Huge dinosaur pelvis found in Colorado

Dead for 140 million years, a specimen of the colossal dinosaur "Supersaurus" is slowly taking shape as researchers uncover more pieces of this giant--one of the longest dinosaurs ever found. Paleontologists last month descovered a pelvic section that stretches more than 6 feet in length and is believed to belong to Supersaurus. Scientists from Brigham Young University in Provo, Utah, unearthed the fossil at the Dry Mesa Quarry near Delta, Colo., the site that has yielded all other parts of this dinosaur.

Supersaurus is an unofficial name, describing a mixed bag of enormous skeletal parts all thought to be part of a single type of sauropod dinosaur from the Diplodocidae family. Scientists have estimated Supersaurus may have spanned 100 to 120 feet, says John S. McIntosh from Wesleyan University in Middletown, Conn., an authority on sauropods who visited the quarry to examine the newly found fossil. Among paleontologists, there is debate over whether Supersaurus represents an entirely new genus in the Diplodocidae family or a larger species of the genus Diplodocus. With its long, slender neck and even longer, whip-like tail, Diplodocus looked something like a plant-munching cantilever bridge.

The recent Dry Mesa find consists of a pelvic bone attached to the sacrum, which are several vertebrae fused together to withstand the tremendous forces borne by this part of the body. Other oversized parts discovered in the quarry are a shoulder blade, a neck vertebra, some tail vertebrae and another pelvic bone. While all have been lumped together under the name of Supersaurus, McIntosh says, "it is not definite that all of these bones are from the same animal or even the same kind of animal." He adds, though, that "there is a better than 50/50 chance Supersaurus is valid."