Cheetah's you probably already know they're the world's fastest land animal they can go from zero to 60 in three seconds covering the length of an asian elephant with each stride but here are five things you probably didn't know about cheetahs cheetahs are one of the few big cats that can't roar instead these carnivores purr much like a house cat also they chirp loudly enough to be heard a mile away these chirps Gary from cheetah to cheetah one theory is that this may allow them to identify each other cheetahs are the only big cat that can't fully retract their claws Aysen onyx jubatus is a cheetah scientific name Aysen onyx means no move claw in greek their claws are actually more similar to a dogs than to those of other cats helping cheetahs maintain traction and gain speed while running their muscular tail which can be over two and a half feet long helps cheetahs whether hunting prey the tail acts like a rudder allowing cheetahs to quickly change direction while running it provides counterbalance as they zigzag across grasslands during a chase unlike other big cats cheetahs hunt primarily by day relying on their exceptionally keen eyesight dark tear marks below cheetahs eyes may help reduce glare from the Sun much like the eye black that some professional athletes wear without the cover of darkness cheetahs camouflage themselves in the tall grass of the savanna typically getting as close as a football fields width away from their prey before making the chase while most cheetahs live in Africa a subspecies of the big cat lives in central Iran these Asiatic cheetahs are genetically distinct from their African counterparts unfortunately they're critically endangered with only an estimated 50 individuals remaining the cheetah population has declined from an estimated 100,000 in the early 1900's to around 7,000 today according to recent estimates cheetahs are under threat from humans poaching habitat loss and vehicle collisions have contributed to their decline plus humans hunt antelopes warthogs and other prey species that cheetahs rely on in Namibia farmers sometimes shoot cheetahs in retaliation for livestock killings one successful conservation program involves placing livestock guarding dogs with farmers the dogs scare away these big cats which are built more for speed than fighting.