Rachel C. Benton is Park Paleontologist at Badlands National Park.

Dennis O. Terry Jr., is Associate Professor in the Department of Earth and Environmental Science at Temple University in Philadelphia.

Emmett Evanoff is Associate Professor in the Department of Earth and Atmospheric Sciences at the University of Northern Colorado in Greeley, Colorado.

H. Gregory McDonald¿is Senior Curator of Natural History in the National Park Service Museum Management Program.