The main objective of this project is to study the paleoecological response of leporids (rabbits and hares) from a classic Eocene-Oligocene Trasition (EOT) fossil sequence of northwestern Nebraska known as the White River Group. Over the past several decades, we have amassed a considerable collection from these deposits that are enhanced by high-resolution chronology and GPS location data. We will use a multiproxy approach to analyze changes in fossil leporid dental structure in evolutionary response to the EOT.