Local News

New Clues at the Heart of First-Ever Dinosaur Find

Posted April 19, 2000 7:00 a.m. EDT

— The world's first dinosaur with a fossilized heart is now on display at the North Carolina Museum of Natural Sciences. The 66-million-year-old fossil could change what we know about dinosaurs.

NicknamedWillo,North Carolina scientists uncovered the 600-pound, 13-foot-long Thescelosaurus in South Dakota in 1993. Willo was named for the wife of a rancher on whose property the remains were found.

What made the find so special was a grapefruit-sized object found in the dinosaur's chest cavity. It turned out to be a heart, complete with ventricles and aorta.

"What we really have is almost kind of a cast. It preserves perfectly the structure of the heart, but it's a replacement," says Dr. Dale Russell, an N.C. State University paleontologist.

Even after thorough examinations, the find was hard for scientists to believe.

"All of us knew, especially me, that you can't preserve a dinosaur heart. That's absolutely impossible. It isn't done. It's never been recorded," says Russell. "Well OK, I had to adjust my horizons on that on. It was a heart."

Scientists atN.C. State's College of Veterinary Medicinebuilt3-D imagesof the heart using CT scans.

Tests found Willo had a strong heart that was more like that of a mammal than a bird or reptile.

"At least the end of the Cretaceous -- probably all dinosaurs had very similar hearts and therefore the whole dinosaur world could have been a very warm-blooded, endothermic -- skip those terms, high-metabolic rate world," says Reese Barrick, an N.C. State University geologist.

That possibility challenges fundamental theories about how and when dinosaurs evolved and how they lived and ate.

Now that they know what to look for, paleontologists will search for more dinosaur hearts and perhaps change perceptions of these fascinating creatures.

More work will be done on dinosaurs at the newly-created Center for the Exploration of theDinosaurian World, a joint project between the Museum of Natural Sciences and N.C State.

The announcement of the finding will be published Friday in the journal"Science."