related tags: 615F5E 615F5F ACA9A4 B0ABA0 C7C2B6 D0C5AE D2D1CF D4D2CD ancestral ash ashfall beds camel camels cap formation fossil fossils grandis group hollow jawbone jawbones mandible mandibles member miocene nebraska ogallala procamelus rock skeleton skeletons tuff volcanic 888379 908671