Acinonyx

Acinonyx is a genus that is within the Felidae family, also known as the cat family. The only living species of the genus and most commonly known, the cheetah (A. jubatus) inhabits the open grasslands of Africa and Asia along with parts of Iran. This genus represents a highly adapted lineage within the felids, which specialize in speed and open-terrain hunting. Evidence suggest the Acinonyx genus evolved from other feline ancestors early on, to become specialized in stealth and running.

The main reasons for all but one species going extinct revolve around climate changes, humans driving these species out of their habitats, and their prey populations shrinking. Climate drastically changed starting in the Pleistocene period, making it difficult to survive in open terrain and grasslands upon which these cats depend. Human civilization also began to change and expand resulting in lots of these species to lose their home or hunting grounds. This also forced some species to be isolated making reproducing more difficult. Another factor of humans expanding was the lack of prey for these cats; their prey were being hunted by humans or being forced from their habitats. These problems played a huge role in the extinction of the historic Acinonyx species.

Fossil remains related to cheetah-like cats were excavated that date back to the late Pliocene and Middle Pleistocene, indicating a wide time range. These cats occurred across much of the old world 10,000 years ago, some extinct species such as A. pardinensis and A. intermedius were found in parts of Europe and Asia. Several similar species classified in the genus Miracinonyx lived in North America at the same time; these may have been more closely related to the genus Puma.

A primary characteristic of this genus are bodies adapted for speed and swiftness; however the species at the time were much different in morphology. Species found 10,000 years ago show a large and vigorous build for these cats compared to the cheetah which has accommodated to fast prey, with a much slimmer build enabling a quick pursuit. Acinonyx species are also unable to retract their claws fully, this can be a disadvantage in some cases. However claws give extra traction while running.