The bottom of a small coulee in southwestern South Dakota is covered with thousands of Depressions from animals hooves. Several hundred of these depressions ( hoof prints) were filled with “cow pies” deposited by a herd of grazing titanotheres (rhinoceros – like mammals) which made the original depressions some 35 million years ago. Recently about 360 of these fossilized “titanothere pies” were removed from the depressions for study at the museum.

These stony “cow pies” contain many fossil plant remains as well as insect trails which speak to the diet of the titanotheres that left them and to the insects that visited them before they were fossilized.
– Bruce R. Erickson, Fitzpatrick Chair of Paleontology