Cheetahs

Acinonyx is a genus of feline, the only living species of which is the cheetah (A. jubatus) that inhabits the open grasslands of Africa and Asia in parts of Iran. This genus represents a highly adapted lineage within the felids, which specialize in speed and open-terrain hunting. Evidence suggest that 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 changed dramatically, 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 losing their homes or hunting grounds. This also forced some species to be isolated, making reproducing more difficult. Food scarcity became another consequence of human expansion as their prey were being forced from their habitats or hunted by humans. 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 from 10,000 years ago show that these cats had a larger and more vigorous build than the cheetah, which has specialized in hunting fast prey, with a much slimmer build, enabling a quick pursuit. Acinonyx species are also unable to retract their claws fully, which can be a disadvantage in some cases. However, claws also give extra traction while running.