OSKALOOSA, Iowa (AP) — Researchers recently found the remains of another mammoth at an Oskaloosa farm where scientists unearthed a nearly complete mammoth skeleton earlier this year.

Jim North, a professor at William Penn University, told the Oskaloosa Herald (http://bit.ly/NYi3Sv ) the discovery of shoulder bones of two distinct mammoths and fragments of a tusk is rare in the Midwest.

The remains appear to date back about 12,000 years.

Dave Brenzel, a program naturalist at the Indian Creek Nature Center, said the fossils were found with remains of trees, offering clues about the environment when the animals lived.

"The rarity is that we found them where they lived," Brenzel said. "Two were entombed in their environment."

The farm's owner, who has asked not to be identified, discovered the bones about two years ago when he and his sons noticed a 4-foot-long leg bone protruding from a creek bed.

Researchers have been studying the southern Iowa site since this spring. About 25 people excavated at the site Sunday, including scientists from the University of Iowa, Iowa State and local volunteers.

Mike Goudy, a science teacher at Oskaloosa High School, and six of his students were among those digging out the site.

"We're putting them to work as soon as we can," he said.

Researchers and volunteers have excavated 10 to 12 feet to uncover the remains of the mammoths and their environment.

___

Information from: The Oskaloosa Herald, http://www.oskaloosaherald.com