Wesleyan has a collection of vertebrate bones from the Lower Miocene Agate Springs locality (Nebraska); the fauna at the site has been reconstructed in a mural at the Smithsonian Institution in Washington (see below); a description of life 21 million years ago is also available at this website.

Wesleyan has a large display of bones, dominated by those of the pig-size rhinoceros Menoceras arikarense, which has been brought to life for us by artist Kelly Taylor.