Black wildebeest
Features necessary for defending a territory, such as the horns and broad-based skull of the modern black wildebeest, have been found in their fossil ancestors. The earliest known fossil remains are in sedimentary rock in Cornelia in the Orange Free State and date back about 800,000 years. Fossils have also been reported from the Vaal River deposits, though whether or not they are as ancient as those found in Cornelia is unclear. Horns of the black wildebeest have been found in sand dunes near Hermanus in South Africa. This is far beyond the recorded range of the species and it has been suggested that these animals may have migrated to that region from the Karoo.
Popo Agie Wilderness
Over 300 lakes and several tributaries of the Wind River are located in the wilderness. Rare reports of wolves have been documented and are considered to be from the wolf recovery efforts commenced in the late 20th century in Yellowstone National Park to the north. Additionally, reports of grizzly bears have been documented but they too are rare. Black bears, moose, elk, and pronghorn are the more commonly sighted megafauna. Trumpeter swans, bald eagles, hawks, and falcons inhabit the wilderness, especially near lakes and streams. Eight species and subspecies of trout, including a few found only in the Yellowstone region exist as well. The forest is dominated by lodgepole pine and Douglas fir, Engelmann Spruce, and subalpine fir at higher elevations up to the tree line.