Proscalops Deep River Formation Philip R. Bjork Brule Formation List of the Cenozoic life of South Dakota List of the Cenozoic life of Nebraska List of the prehistoric life of South Dakota List of the prehistoric life of Nebraska List of the Cenozoic life of Montana List of the prehistoric life of Colorado List of the prehistoric life of Montana List of the Cenozoic life of Wyoming List of the prehistoric life of Wyoming List of the Cenozoic life of Colorado Monroe Creek Formation Sharps Formation 2020 in paleomammalogy