Experts cast doubt on dinosaur 'dance floor'

So maybe there was no dinosaur dancing after all.

A group of paleontologists says there are no signs of dinosaur tracks at a remote spot along the Utah-Arizona border that previously had been described by University of Utah geologists as a "dinosaur dance floor" for its density of tracks.

"We didn't observe a single footprint," said Andrew Milner, paleontologist at the St. George Dinosaur Discovery Site at Johnson Farm in southwestern Utah.

He was one of four paleontologists who hiked into the area last week following a heavily publicized study claiming there were more than 1,000 previously unknown dinosaur tracks crammed onto a 3/4 acre site on the Arizona portion of Vermillion Cliffs National Monument.

"We went up there optimistic, really hoping we were going to find footprints," Milner said Friday.

They quickly determined there were none. Instead, it was a dense collection of erosion-caused potholes in the sandstone, they said.

And the supposed tail-drag marks in the rock? Probably another result of erosion, the paleontologists said.

Marjorie Chan, the University of Utah researcher who co-authored the "dinosaur dance floor" study, said she's open to the paleontologists' views and says she'll team up with other researchers for another examination of the site.

"I'm interested in the truth no matter what the outcome is," Chan said.

The study authored by Chan and graduate student Winston Seiler sent a ripple of excitement among dinosaur enthusiasts: the prospect of scores of footprints providing valuable clues about dinosaurs 190 million years ago, when vast stretches of the West were a Sahara-like desert.

The study was published in the October issue of Palaios, a peer-reviewed international journal of paleontology.

Some who reviewed the study before it was published raised the possibility that the tracks were actually potholes, but Chan said she thought she and Seiler made compelling counter-arguments.

For the dinosaur-experts who investigated the site Oct. 30 — including two from the Bureau of Land Management — the results were clear and worthy of more analysis.