Really big show
Mammoths and mastodons — another elephant-like prehistoric creature — once roamed North America before disappearing about 11,700 years ago. Over the years, the remains of about 300 mastodons and 30 mammoths have been recovered in Michigan. And as local farmer and property owner James Bristle recently discovered, the area near Chelsea once was home to at least one of the gigantic animals.
In early October, Bristle was installing drainage pipe at a low spot in a wheat field surrounded by soybeans. A backhoe operator digging a trench uncovered a roughly 3-foot-long bone that was later identified as part of a mammoth pelvis.
“We didn’t know what it was, but we knew it was certainly a lot bigger than a cow bone,” Bristle says.
The farmer contacted the U-M Museum of Paleontology and its director, Dan Fisher, professor in U-M’s Department of Earth and Environmental Sciences and in the Department of Ecology and Evolutionary Biology. Fisher has excavated roughly 30 mammoths and mastodons in North America over the past 36 years.
“When my 5-year-old grandson came over and saw the pelvis, he just stood there with his jaw wide open and stared. He was in awe,” Bristle says. “So I think this was the right thing to do.”
Ready, set, go
Bristle gave the Michigan team one day to recover the remains. The crew included University paleontologists and an excavator who donated his time and worked all day at the site in Lima Township, roughly 10 miles southwest of Ann Arbor. They were able to recover about 20 percent of the animal’s bones, including the skull and two tusks, numerous vertebrae and ribs, the pelvis, and both shoulder blades.They worked from early morning to nearly sunset. After the bones were recovered, the pit was refilled.
The bones are from an adult male mammoth that likely lived 11,700 to 15,000 years ago. The site holds “excellent evidence of human activity” associated with the mammoth remains, Fisher says.
“We think humans were here and may have butchered and stashed the meat so that they could come back later for it,” he says.
The team’s working hypothesis is that ancient humans placed the mammoth remains in a pond for storage. Evidence supporting that idea includes three basketball-sized boulders recovered next to the mammoth remains. The boulders may have been used to anchor the carcass in a pond. Caching mammoth meat in ponds for later use is a strategy Fisher says he has encountered at other sites in the region.
The researchers also recovered a small stone flake that may have been used as a cutting tool next to one of the tusks. And the neck vertebrae were not scattered randomly, as is normally the case following a natural death, but were arrayed in their correct anatomical sequence, as if someone had “chopped a big chunk out of the body and placed it in the pond for storage,” Fisher says.
The first step toward confirming this hypothesis will be to wash the bones and look for cut marks that indicate butchering.
The date that humans arrived in the Americas is unclear and is the topic of heated debate among archaeologists. Depending on the age of the Lima Township mammoth and confirmation of the suspected links to human hunters or scavengers, the recent find could help push back the date for human habitation in what is now Southeast Michigan.
Not woolly, “Bristle”
Most of the mammoth finds in Michigan are not as complete as the remains uncovered by the U-M team, Fisher says.
The newly named “Bristle Mammoth” (James Bristle’s last name is pronounced bris-lee, appropriately enough) appears to be a hybrid between a woolly mammoth and a Columbian mammoth, he says. The remains of more than 30 mammoths have been recovered in Michigan over the decades, and more than half of them are hybrids of this type.
Fisher is working on plans to display the bones at the U-M Museum of Natural History.
One possibility might be to combine the partial skeleton from the Bristle Mammoth with bones from other Michigan mammoths to form a complete mammoth skeleton for display at the museum. Fiberglas casts of the bones would likely be used in the mounted specimen, he says. The display would be a partnership between the U-M Museum of Paleontology and the U-M Museum of Natural History.
“We are enormously thankful to landowners like Jim Bristle who are willing to donate material like this,” Fisher says. “Our knowledge of the past depends entirely on the generosity of landowners who provide us with this type of material.”
“This isn’t just mine. It belongs to everybody,” Bristle says. “This is our way of giving back. A lot of people will benefit from being able to see this mammoth for many years to come. If I can make people happy by doing that, then I consider that a good day.”