Black wildebeest
The black wildebeest or white-tailed gnu ("Connochaetes gnou") is one of the two closely related wildebeest species. It is a member of the genus "Connochaetes" and family Bovidae. It was first described in 1780 by Eberhard August Wilhelm von Zimmermann. The black wildebeest is typically in head-and-body length, and the typical weight is . Males stand about at the shoulder, while the height of the females is . The black wildebeest is characterised by its white, long, horse-like tail. It also has a dark brown to black coat and long, dark-coloured hair between its forelegs and under its belly.
Elasmotherium
The white rhinoceros at an estimated weight of 2.3 tonnes has been photographed galloping at a speed of about . In a gallop, all feet are off the ground ("ballistic phase") twice a cycle, a feat that elephants, at 2.7–10 tonnes, cannot perform. They can walk up to ; however, their straight, relatively inflexible legs are those of striders, not the bent and spring-like legs of gallopers, which use haunches, ankle mobility and knee flexion to spring off the ground on alternative legs of a pair. "Elasmotherium" legs are sufficiently like those of the White Rhino to hypothesize a similar gait even though "Elasmotherium" weighed 4.5-5 ton.