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Calvin News

Dig that Mastodon

Fri, Jun 18, 1999
Phil de Haan

A Calvin College professor of geology and a crew of his students are working on "a dream come true" this summer.

They are unearthing the skeleton of a mastodon - a now-extinct animal that once was prolific in North America, including Michigan.聽

The mastodon was uncovered by a local construction company, working on the site of a new church just east of Grand Rapids. When workers saw one of the mastodon's large molars shining in the dirt they knew they had uncovered something other than the skeleton of a dog or a deer. Church members called Calvin, knowing of the school's outstanding geology and archaeology departments.聽

Calvin professor Ralph Stearley was chosen to head up the tricky task of excavating the mastodon remains. Stearley has worked on such excavations in the past and has broad expertise in paleontology and paleoecology. Yet he never imagined such an opportunity might come his way so close to home.聽

"To be able to work on a dig such as this is an amazing opportunity for me and my students," said Stearley.聽
Stearley says there are over 200 mastodon sites in the state of Michigan, but at most of those sites only a bit of the animal was uncovered - perhaps a tooth or a bone. This most recent find is a big one - much of the mastodon is being excavated. Only three dozen or so such sites exist in the state with many of those located in southeast Michigan. Interestingly, Grand Valley State University had a mastodon site locally in the 1980s.聽

Mastodons, along with mammoths and modern elephants, are members of the order Proboscidea. As adults they stood between eight and 10 feet at the shoulder and weighed between four and six tons. Their teeth had blunt cones which scientists speculate were used to browse on herbs, shrubs and trees. Mastodons probably became extinct about 10,000 years ago. Today, paleontologists are trying to figure out why.聽

The Calvin crew includes Stearley, Calvin students Anne Albers (Holland/Holland Christian), Paul Petersen (Crawfordsville, IN/Southmont High), Beth Vanden Berg (Zeeland/Holland Christian) and Mike Vanden Berg (Grandville/Calvin Christian) and several community volunteers. Calvin geology and geography professor Jim Clark has been heading up the site survey.聽

Much of the summer will be spent digging out the remains. Attention then will be turned to reconstructing as much of the animal as is possible. The process is time consuming. The digging out is done by hand, with either the fingers or perhaps popsicle sticks, so as not to damage the bones, teeth, tusks and other materials. Often large chunks of soil are brought back to the labs at Calvin, with the remains intact, so that the items can be extricated in the lab. Once out the bones, teeth and tusks need to be cleaned and then they need to be strengthened - usually with a soaking in a solution made up of water and Elmer's glue. After drying the parts will be ready for reconstruction.聽

"It's an immense task," said Stearley. "There are so many components to a project of this magnitude. But this is what it's all about. This is what the students study in the semester. Now they'll have a chance for literal hands-on work. It's a terrific opportunity for them and for me."聽

Stearley has been involved in excavations such as this before. He received his B.A. in physical anthropology from the University of Missouri in 1975. He later switched tracks to geology -- studying paleontology and sedimentology at the University of Utah (master's) and the University of Michigan (Ph.D. in 1990). During 1991-1992 he was a research scientist at the Illinois State Museum which curates one of the largest collections of mastodon remains in the U.S. and did a mastodon mount for the Grand Rapids Public Museum.