Brontotheriidae, also called Titanotheriidae, is a family of extinct mammals belonging to the order Perissodactyla, the order that includes horses, rhinoceroses, and tapirs. Superficially they looked rather like rhinos, although they were not true rhinos and are probably most closely related to horses. They lived until the very close of the Eocene.
Dimensions of the fossil skull replica: 26" long x 13" wide x 24" tall.
The skull and lowers are from Custer County, SD. The skull (upper) was collected on a cattle ranch in 1992 and the lowers found in the same area but, later in 1999.
Brontops sp. (robustus?)
Crazy Johnson Member
Custer County, SD
$795 (plus shipping)
Titanothere skull replica – Brontotherium Brontops
Brontotheres have teeth adapted to shearing (cutting) relatively nonabrasive vegetation. Their molars have a characteristic W-shaped ectoloph (outer shearing blade).
The history of this group is well known, due to an excellent fossil record in North America. The earliest brontotheres, such as Eotitanops, were rather small, no more than a meter in height, and were hornless.
Brontotheres had massive body sizes, although some small species, such as Nanotitanops did persist through the Eocene. Some genera, such as Dolichorhinus, evolved highly elongated skulls. Later brontotheres were massive in size, up to 2.5 m (8.2 feet) in height with bizarre hornlike skull appendages. For instance the North American brontothere Megacerops had large sexually dimorphic paired horns above their noses. The sexually dimorphic horns suggest that brontotheres were highly gregarious (social) and males may have performed some sort of head clashing behavior in competition for mates. However, unlike rhinos, the horns of brontotheres are composed of bone, the frontal bone and nasal bone, and were placed side-to-side rather than front-to-back.
Brontotheres probably became extinct due to an inability to adapt to drier conditions and tougher vegetation (such as grasses) that spread during the Oligocene.