A mysterious piece of bone presented to Iowa State University anthropologist Matthew Hill sent him on a scientific journey that resulted in the discovery of the oldest stag-moose specimen ever recorded in North America.
The stag-moose, an ancestor or the common moose, roamed the North American plains during the Ice Age. By today's standards, it was an unusual creature.
"It had the body of a moose, a face like an elk and the males had an antler rack that's like neither," Hill said. "The antlers are goofy, the shaft goes straight out from the side of the head for a ways, and then develops into two or three palms that sprout multiple tines. No two are alike."
When Hill first came across the stag-moose antler he was puzzled as to what it could be.
"I knew it did not belong to a white-tailed deer, elk or caribou. It looked sort of like a moose antler, but not quite -- it was different," Hill said. "I suspected it might be stag-moose, so I sent a picture to a colleague at the Illinois State Museum to compare it with specimens in their collections. He confirmed my suspicion."
That confirmation was all it took to send Hill on a mission to learn more about the stag-moose and when the animal was in Iowa. Specifically, he wanted to determine the age of the antler and and that of two other specimens he located.
After sending them to a lab for radiocarbon dating, the results were even greater than he anticipated. One of the samples was more than 30,000 years old, which made it the oldest stag-moose specimen discovered in North America, according to Hill.
"It means that these animals were here before the glaciers covered central Iowa, and that they returned for a short time after the glaciers retreated as well," he said. "Still, we don't know a whole lot about the ecology of these animals. When they appeared, their numbers on the landscape, the cause of their demise, and what other animals they were living with side-by-side? There are just a whole lot of questions and this will be a great opportunity to learn more."
Dry weather conditions in Iowa this summer and last year have increased the chances of people stumbling across specimens that have become dislodged.
"Recent weather patterns have been very conducive to finding specimens. Flooding removed vegetation from cut banks and sand bars, and drought has lowered water levels significantly," Hill said
"Animals die on the landscape, they get buried, and rivers meander around and erode and rebury remains. It's the formation of the fossil record, and that's what we're interested in."