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 70 to 75 mph in short bursts covering distances up to 1,600 ft, and has the ability to accelerate from 0 to 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.
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's chest is deep and its waist is narrow. The coarse, short fur of the cheetah is tan with round black spots measuring from 0.79 to 1.18 in across, affording it some camouflage while hunting. There are no spots on its white underside, but the tail has spots, which merge to form four to six dark rings at the end. The tail usually ends in a bushy white tuft. The cheetah has a small head with high-set eyes. Black "tear marks" running from the corner of its eyes down the sides of the nose to its mouth keep sunlight out of its eyes and aid in hunting and seeing long distances. Its thin and fragile body make it well-suited to short bursts of high speed, but not to long-distance running.
Agility, rather than raw speed, accounts for much of the cheetah's ability to catch prey. Cheetahs can accelerate four times as fast as a human (thanks to greater muscle power) and can slow down by 14 kilometers per hour in one stride. They can hunt successfully in dense forests.
Some cheetahs have a rare fur pattern mutation of larger, blotchy, merged spots. Known as "king cheetahs," they were once thought to constitute a separate subspecies but are in fact African cheetahs; their unusual fur pattern is the result of a single recessive gene. The "king cheetah" has only been seen in the wild a handful of times, but it has been bred in captivity.
The cheetah's paws have semi-retractable claws (known only in three other cat species: the fishing cat, the flat-headed cat and the Iriomote cat), offering extra grip in its high-speed pursuits. The ligament structure of the cheetah's claws is the same as those of other cats; it simply lacks the sheath of skin and fur present in other varieties, and therefore, with the exception of the dewclaw, the claws are always visible.
Adaptations that enable the cheetah to run as fast as it does include large nostrils that allow for increased oxygen intake, and an enlarged heart and lungs that work together to circulate oxygen efficiently. During a typical chase, its respiratory rate increases from 60 to 150 breaths per minute. While running, in addition to having good traction due to its semi-retractable claws, the cheetah uses its tail as a rudder-like means of steering to allow it to make sharp turns, necessary to outflank prey animals that often make such turns to escape.
The cheetah is a vulnerable species. Of all the big cats, it is the least able to adapt to new environments. It has always proved difficult to breed in captivity, although recently a few zoos have managed to succeed at this. One technique has been to introduce a dog as a playmate and guard dog to enable a captive cheetah to feel less threatened.
See VIDEOS MAMMALS for several Cheetah video. Most of these photos were taken in the Masai Mara and Serengiti.