Cheetah

The cheetah (Acinonyx jubatus) is a large feline (family Felidae, subfamily Felinae) inhabiting most of Africa and parts of Iran. It is the only extant member of the genus Acinonyx. The cheetah can run faster than any other land animal— as fast as 112 to 120 km/h (70 to 75 mph)undefined in short bursts covering distances up to 500 m (1,600 ft), and has the ability to accelerate from 0 to 100 km/h (62 mph) in three seconds. This cat is also notable for modifications in the species' paws. It is one of the few felids with semi-retractable claws.undefined

Etymology
The word "cheetah" is derived from the Sanskrit word citrakāyaḥ, meaning "variegated", from the Hindi 'चीता' (cītā).

Genetics, evolution, and classification
The genus name, Acinonyx, means "no-move-claw" in Greek, while the species name, jubatus, means "maned" or "crested" in Latin, a reference to the dorsal crest found in cheetah cubs.

The cheetah has unusually low genetic variability. This is accompanied by a very low sperm count,motility, and deformed flagella. Skin grafts between unrelated cheetahs illustrate the former point, in that there is no rejection of the donor skin. It is thought that the species went through a prolonged period of inbreeding following a genetic bottleneck during the last ice age. This suggests that genetic monomorphism did not prevent the cheetah from flourishing across two continents for thousands of years.undefined

The cheetah likely evolved in Africa during the Miocene epoch (26 million to 7.5 million years ago), before migrating to Asia. Recent research has placed the last common ancestor of all existing populations as living in Asia 11 million years ago, which may lead to revision and refinement of existing ideas about cheetah evolution.

The now-extinct species include: Acinonyx pardinensis (Pliocene epoch), much larger than the modern cheetah and found in Europe, India, and China; Acinonyx intermedius (mid-Pleistocene period), found over the same range. The extinct genus Miracinonyx was extremely cheetah-like, but recent DNA analysis has shown that Miracinonyx inexpectatus, Miracinonyx studeri, and Miracinonyx trumani (early to late Pleistocene epoch), found in North America and called the "North American cheetah" are not true cheetahs, instead being close relatives to the cougar.