The cheetah (Acinonyx jubatus) is well known as the fastest land animal on earth; the cheetah is capable of speeds of up to 75mph for short distances and can go from 0 to 60 in three seconds. The cheetah is also one of the only felines that can not retract its claws.
Unfortunately, the cheetah is a vulnerable species and has unusually low genetic variability. 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.