Oskaloosa.com

August 20, 2012

Second mammoth discovered

By DUANE NOLLEN
The Oskaloosa Herald

OSKALOOSA — Scientists have found more mammoth remains at a dig site in eastern Mahaska County that are creating a stir.

Researchers recently uncovered the glenoid cavities — shoulder bones — of two distinct mammoths and fragments of a tusk at the dig site.

Scientists from the University of Iowa, Iowa State University, the Indian Creek Nature Center, William Penn University, Indian Hills Community College and Oskaloosa High School science faculty and students were digging at the site Sunday morning. In all, about 25 people were excavating at the site.

Dr. Jim North of William Penn University said the find is significant.

“There are few sites in the Midwest that have more than two mammoths,” he said. “We’re thinking that there are two separate organisms that died here.”

What really makes the find significant is that the remains of the animals' environment also were found with the fossilized bones.

“The rarity is that we found them where they lived,” said Dave Brenzel of the Indian Creek Nature Center. “Two were entombed in their environment.”

The fossils were found with remains of trees, such as spruce and fur, that existed when the mammoths lived and the species continue to grow today.

“It’s a cool Ice Age site,” Brenzel said.

Oskaloosa High School science teacher Mike Goudy brought six of his students to the site Sunday to help.

“We’re putting them to work as soon as we can,” he said. “The boys are leaning on the shovels right now.”

Goudy said this is the first time high school students have worked at the site.

“They’re interested in science and really good students,” Goudy said.

Goudy plans to integrate the work at the dig site with his curriculum this fall.

Goudy said he also found a mammoth rib bone when excavation began at the site. Goudy said that he and Pete Eyheralde, of Iowa State University, were digging a drainage trench when he found a mammoth rib bone.

“It was the first day and I found a bone,” he said.

William Penn professor Dr. Janet Ewart also was at the site Sunday for the first time.

“It’s fascinating,” she said. It’s fun to be around fellow scientists who have made such a discovery. “It’s not a lot of dirt and bones — it means something,” she added.

University of Iowa professor emeritus of geoscience Holmes Semken also discussed some fragments of mammoth tusks found at the site.

“The tusk is an ever-growing tooth,” he said.

Semken said the tusk fragments are abnormal because they indicate that the tusk at some points stopped growing.

“The tusk seems to be segmented — growth was arrested from time to time,” he said.

He said that could be caused by either a genetic abnormality or environmental factors.

“I don’t know what caused it,” he said.

Geologists have said the dig site tells an “interesting story,” North said.

Researchers have dug about 10 to 12 feet down and uncovered the fossils and remains of the mammoths’ environment.

Brenzel said what remains a mystery is why the mammoths died out.

There have been seven major extinction events in the Earth’s history, North added.

Herald Editor Duane Nollen can be reached by email at oskynews@oskyherald.com