July 31 , 2016

by DENISE M. BARAN–UNLAND

A historic dinosaur site is getting a second look – and possibly a second hypothesis of how the bones got there.

In June, Joseph Peterson, assistant professor of geology at the University of Wisconsin-Oshkosh; and Jonathan P. Warnock, an assistant professor from the Indiana University of Pennsylvania led a team of researchers at Cleveland-Lloyd Dinosaur Quarry in Utah.

And a New Lenox resident and paleontologist was part of that team.

Steve Clawson, a preparator of fossil vertebrates, is using three-dimensional photography to map the site. He became involved in the project four years ago while writing an undergraduate thesis and anticipates the work at the quarry will continue for another five to seven years.

Clawson, who said he’s worked in the paleontology community about nine years, messaged his contacts letting them know he was seeking interesting projects. Warnock invited him out to the quarry, the largest depository of fossils on Earth, Clawson said.

“It’s every paleontologist’s dream to work on this site, so I jumped on board,” Clawson said.

Clawson is mapping the site of every bone the team finds – how far below the surface it is and its plunge direction both horizontally and vertically, he said. By taking 500 to 1,000 digital photographs at precise angles and scanning them, Clawson can create a 3-D map and video of the site.

Why are such maps important? Because it appears the previous theory of how the bones wound up in the quarry might be incorrect, Clawson said.

The original theory is that the quarry was once a muddy pit. After one dinosaur became stuck, others came to feed on it, got stuck and so on, Clawson said.

“When we compare it to known predator sites – like La Brea Tar Pits in California – nothing makes sense in those terms,” Clawson said. “We don’t see bite marks on the bones. No evidence on the bones that they were trampled. No evidence that anything was struggling in this mud.”

The new theory proposes the bones drifted there, perhaps by way of a flood, Clawson said.

A major problem at the quarry, he said, is that no one ever mapped it accurately, despite records dating back to the 1920s. But then, careful mapping of the site was not a priority at the time, given the existing predator theory and the reason for the interest in the bones.

“Up through the ’80s, people were just going to the quarry to put big impressive dinosaurs in their museum to mount and show people,” Clawson said. “This was an easy place to find them, but they weren’t accurate where they found them.”

While working on the site, Clawson is serving as Warnock’s teaching assistant by training students how to find and excavate bones and then carefully treat the bones with certain chemicals to stabilize them. The bones are extremely fragile, Clawson said, since they have not touched oxygen for 148 million years.

“It’s scary for the students who haven’t done it before, so I ease them through the process,” Clawson said.

Clawson said he grew up collecting rocks. During family outings to Michigan, he shunned the dunes in favor of searching for rocks on the beach. When Clawson was 14, he was accepted into a paleontology program through the University of Chicago, where he met people from the Field Museum of Natural History.

“Soon I was hanging out in the lab every single weekend – every single day in the summer – learning how to become a fossil preparator,” Clawson said.

By age 19, Clawson said he was hired as the staff fossil preparator at the Burpee Museum of Natural History in Rockford.

He bemoans that many paleontologists today specialize in biology rather than geology. The latter perspective is necessary, Clawson feels, in order to accurately interpret an assemblage of bones in terms of time period and evolution.

“We need to know what happened to the animals before we think biology, before we do chemical analyses or extract of soft tissues,” Clawson said.

The researchers’ work at Cleveland-Lloyd Dinosaur Quarry did attract curious visitors and Clawson is glad of that, especially when children become interested. It’s a great way to watch the scientific method unfold, he said.

The team is collecting data and then forming a hypothesis about this “Jurassic crime scene.”

“If we can get kids interested in research at the right time,” Clawson said, “we might be able to make scientists out of them.”

Clawson also hopes the general public is interested in any findings.

Despite discoveries, much of the past is unknown. By studying the past, one can learn more about climate changes throughout history, which helps in understanding climate and its changes today, he said. People can gain better understanding of birds by studying their ancestors, he added.

“There’s a lot that happened before dinosaurs,” Clawson said. “The quarry is 148 million years old, straight out of the Jurassic period. But there were hundreds of millions, if not billions, of years that occurred before this assemblage.”

http://www.theherald-news.com/2016/07/26/new-lenox-paleontologist-creating-3-d-maps-of-historic-jurassic-site/ax6svfi/?page=2