Paleontology experts are investigating the discovery of prehistoric mastodon bones at a Michigan construction site.
Workers found the bones Aug. 31 while excavating a road at a housing development in Byron Center, which is about 13 miles (20.92 kilometers) south of Grand Rapids, the Grand Rapids Press reported.
A University of Michigan researcher said Tuesday that the bones were the remains of a mastodon skeleton estimated to be around 10,000 years old.
"We ended up finding what the University of Michigan has told us were mastodon bones," said Joe Siereveld, an owner of Eagle Creek Homes, the developer in charge of the housing project. "They were deep; really, really deep."
Siereveld said the company currently possesses five large pieces of bone and some smaller pieces. At least two of the pieces are believed to have come from the animal's head. Researchers said they believe the pieces belonged to a male American mastodon that lived for two or three decades.
In cases where a discovery is confirmed as legitimate, the property owners have the option to donate a specimen to the university, said Dan Fisher, director of the University of Michigan Museum of Paleontology. Fisher said the museum may have to become involved in an excavation at the site if the owners decide to donate the item.
"It's their call whether they're going to donate it or not," Fisher said. "The usual pattern is I ask them to think about it, and they let us know when they've decided what they want to do with the material."
Siereveld said the company is considering donating the bones and working with the university at the site.
Fisher said legitimate discoveries of prehistoric animals aren't necessarily uncommon in the area because surrounding lakes that resulted from glaciers made vegetation attractive to mastodons and mammoths.
He estimated two or three such discoveries are made in Michigan a year, with most of the remains estimated to be between 11,000 to 15,000 years old.
"There is very interesting scientific work to be done on them," Fisher said.