This morning Brett, Max, and I visited the next museum on the "Mastodons of Unusual Size" tour, the Joseph Moore Museum at Earlham College in Richmond, Indiana.The Joseph Moore Museum has a small but significant collection of Pleistocene fossils, with a mounted mastodon composite skeleton (above) as one of the centerpiece exhibits. Unfortunately, the teeth on this specimen are damaged and couldn't be measured, but there were several other mastodon teeth in the collection.
The tooth shown above, from Indiana, is a fairly typical lower third molar, with four lophids (the transverse enamel ridges) and a large posterior cingulid (the bumpy ridge at the back of the tooth that looks like a small lophid on the right in the image). Compare this to from another one in the Joseph Moore Museum collection below, from Ohio:
This one is also a lower third molar, but this one has five lophids, and still has a posterior cingulid (posterior is on the left in this image). The five lophid morphology seems to show up in a small percentage of mastodons; we've seen it in only a few specimens so far on this trip, so it nice to find this one at Earlham.We were able to add five teeth to our dataset on this visit. Thanks to JMM Director Heather Lerner for providing access to Earlham's collection.