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Acinonyx jubatus
ADAPTED FOR SPEED
The cheetah holds the distinction of being the fastest land animal, with top speeds of 65 to 70 mph. Cheetahs can only maintain this high speed for a short period of time, so their hunting strategy is adapted to it. Cheetahs will stalk prey until they are close enough to put on a burst of speed and catch up with the prey. They then attempt to trip it by swiping the hind legs, before catching the stunned animal by the face to kill it by suffocation.
Cheetah anatomy reflects a strong specialization in adaptation for speed. The spine of a cheetah is built somewhat like a spring. This gives longer strides due to a more free running motion as the spend bends. This makes the strides almost like bounds, giving greater distance to each.
In addition, cheetahs have large nasal passages that allow for easier breathing while running. The rib cage is smaller and more flat to also aid in breathing and allow more free movement of the legs. A cheetah's body is thin and lanky to make it lighter, and the tail is flattened and the end to act like a rudder when changing directions at top speed. Cheetahs are also the only cats without fully retractable claws. This makes for better traction in running.
CURSE OF SPECIALIZATION
As I have heard it said in many of my classes on evolution and biology, "There are no free lunches in evolution." Every advantage always seems to carry with it some disadvantage, and the cheetah has exemplified this. It seems through such extreme specialization, the cheetah may be causing it's own demise. Many problems come along with this wonderful adaptation for speed.
For one, a cheetah often finds it difficult to keep it's prey. After such exertion to reach the average 60mph speed, a cheetah must rest for a while before eating. Running at such speed increases the cheetah's body temperature greatly, almost to a point where it might cause brain damage. In addition, the cheetah must rest to replenish oxygen to the brain. Anyone who has run to the point of becoming winded knows how much oxygen is expended in such an activity. Therefore, without a rest period the cheetah could cause itself brain damage or death due to temperature or lack of oxygen.
It is during this rest period that the cheetah is apt to lose it's hard won prize. Hyenas, lions, or other large predators can simply walk up to the cheetah and take it's prey. As I have seen in documentaries, the cheetah rarely puts up any resistance at all. Not only is it too tired to resist, but it's lanky build makes for a poor defense against a bulky lion or hyena.
THE ULTIMATE 'WORKING MOTHER'
The disadvantages of adaptation make life especially difficult for cheetah mothers. They are poorly equipped to defend their cubs against other predators, and being solitary animals lack the protection of numbers. A cheetah cubs best defense is to hide until danger passes. (I have seen an even like this in a documentary, but unfortunately cannot remember the name. I will describe it here, apologizing for not being able at the moment to give proper resource reference. I will try to find the information for reference somewhere to give proper credit to the source.) In this incident, a cheetah mother with cube was approached by a group of lions. She was unable to move the cubs in time, so they went with their best defense and remained motionless in the grass. Lions will often kill cheetah cubs, almost as if they realize that cheetahs are competing for the same resources.
The mother tried to diver the lions attention with threats, attempting to move them away from the hiding cubs. Unfortunately, the lions found some of the cubs and killed them. Their mother was helpless to defend them. Sadly, the following morning the cheetah mother called for her cubs in the typical chirping like cheetah 'bark'. The surviving cub responded to it's mothers call and came out of hiding. She continued to call for the dead cubs for a while before giving up and moving on.
Incidents like this are no uncommon. Cheetah mothers often lose cubs as well as the prey intended for them to other predators. It is no wonder such small numbers survive. It is also these small numbers that may cause yet another problem. Limited populations eventually leads to inbreeding, causing greater chances of genetic defects and limiting chances of survival.
KING CHEETAHS
One final note worth mentioning is the 'king' cheetah. It was once thought that this type was a separate species of cheetah. Few believed it existed until one was caught on film. Biologists later found this was not a new species, but merely a very rare mutation in which the spots of the coat appear more like stripes. There is no such mutation in other spotted cats. These rare mutants have been bred in captivity, but with great difficulty.
Sources: "Big Cats : Kingdom of Might" Tom Brakefield. Voyaguer Press, Stillwater MN. 1993
THE FUTURE
It would seem that a pretty grim future is portrayed for the cheetah. Some opinions are that the cheetah is on the road to extinction due to it's own extreme specialization. It does seem odd that evolution would allow a species to get to a point where it causes it's own extinction, however. It may simply be that cheetahs are in a period of extreme selective pressure. Even if this is not the case, there have been successful breeding in zoos and conservation efforts. If conservation only serves to prolong the existence of cheetahs and they are destined to go extinct in the wild, the species may survive in captivity.