Cheetah

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) 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.

The cheetah is a unique felid, with its closest living relatives being the puma and jaguarundi of the Americas. This cat is notable for modifications in the species’ paws, being one of the few felids with only semi-retractable claws.

Its main hunting strategy is to run down swift prey such as various antelope species and hares. Almost every facet of the cheetah’s anatomy has evolved to maximise its success in the chase, the result of an evolutionary arms race with its prey. Due to this specialisation, however, the cheetah is poorly equipped to defend itself against other large predators, with speed being its main means of defence.

In the wild, the cheetah is a prolific breeder, with up to nine cubs in a litter. The majority of cubs do not survive to adulthood, mainly as a result of depredation from other predators. The rate of cub mortality varies from area to area, from 50% to 75%,[11] and in extreme cases such as the Serengeti ecosystem, up to 90%. Cheetahs are notoriously poor breeders in captivity, though several organisations, such as the De Wildt Cheetah and Wildlife Centre, have succeeded in breeding high numbers of cubs.

The cheetah is listed as vulnerable, facing various threats including competition with and predation by other carnivores, a gene pool with very low variability, and persecution by mankind. It is a charismatic species and many captive cats are “ambassadors” for their species and wildlife conservation in general.

Etymology
The word “cheetah” is derived from Hindi ‘चीता’ (cītā), in turn from Sanskrit citrakāyaḥ, meaning “variegated”.

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.

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; and 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.[17]

Subspecies
Although many sources list six or more subspecies of cheetah, the taxonomic status of most of these subspecies is unresolved. Acinonyx rex—the king cheetah—was abandoned as a species after it was discovered that the variation was caused by a single recessive gene. The subspecies Acinonyx jubatus guttatus, the woolly cheetah, may also have been a variation due to a recessive gene.