Jawaban:

Cheetahs belong to Acinonyx, which means "unmovable nail" in Greek (although all cats have retractable claws, a cheetah's claws don't entirely retract) — according to Marker, they are the only surviving member of this genus, which has been around for perhaps 5 million years.

The feature that distinguishes the Big Cats from the rest of the Felidae family is their ability to roar because they have a floating hyoid bone and a specially adapted larynx. Cheetahs don't have this adaptation and, as a matter of fact, make more of a chirping sound and are also known to purr.