A Corvette Twin Turbo accelerates at about 7.2 meters per second. A Ferrari Enzo boasts about 8.1 meters per second, which takes it from zero to 60 mph in about 3.3 seconds [source: AskMen]. A cheetah picks up speed faster than both of those cars. Its specialized body accelerates at 10 meters per second and gets up to 40 mph (64 kph) in three strides [source: Cheetah Conservation].
The cheetah is the fastest land animal, achieving a top speed of about 70 mph (113 kph) [sources: Blue Lion, Defenders of Wildlife]. This incredible speed comes with a price, though -- a cheetah is a rather puny large cat. (It looks a lot like a leopard, but you can tell a cheetah by the bilateral, teardrop-shaped stripes running from either side of its nose to its eyes.) It's small and lightweight, usually less than 3 feet (1 meter) tall and about 4 feet (1.2 meters) long [source: Defenders of Wildlife]. More than half of that length is the tail, which is crucial to maintaining control during a 70 mph chase. The very adaptations that make it the fastest cat alive also make it highly susceptible to extinction, as we'll see on the next page.
On the open savannas of Iran and parts of Africa, cheetahs are amazing examples of specialization -- the evolutionary adaptation to very specific environmental conditions. In this case, the specialization is for speed. Going after impalas, gazelles and small wildebeests, the cheetah is a blur, and the chase is short-lived, typically lasting about 30 seconds. Cheetah moms spend a lot of time teaching their cubs to chase, sometimes dragging live animals back to the den so the cubs can practice the chase-and-catch process.
When a cheetah overtakes its prey, it knocks it down and takes it out with a bite to the neck. It then eats as quickly as possible. If a lion comes along, the cheetah will abandon its catch -- it can't fight off a lion, and chances are, the cheetah will lose its life along with its prey if it doesn't get out of there fast enough.
Speed is never an issue, of course. Speed is how the cheetah survives as a predator that can't defend itself in a fight. And that speed is the result of some very special physical attributes. On the next page, we'll see how a cheetah manages its unmatched speed.
Cheetahs: Born to Run
Any animal that can go from zero to 40 mph in three strides must have a very specialized body. The cheetah is so built for speed, it really can't do much else.
A cheetah's speed starts with aerodynamics. Its slender body, small head, flattened rib cage and long, thin legs minimize air resistance. It typically only weighs about 125 pounds (57 kg), so its muscles don't have that much weight to carry.
Everything about a cheetah contributes to its superlative running skills. An oversized, powerful heart pumps huge amounts of blood; large lungs and nostrils allow for fast and deep air intake. A cheetah's eyes are extra long so they can get a fast, wide-angle view of their surroundings even at top speed. It has an extra flexible spine that curves with each stride, acting something like a spring for the back legs. The large tail is both a rudder and counterweight to a cheetah's body so it doesn't spin out during fast turns.
It's the stride, though, that makes most people gasp. The flexible spine, combined with unique leg muscles that give a cheetah's legs incredibly broad swing range, allow the animal to achieve a stride of 25 feet (7.6 meters) [source: Cheetah Conservation]. It's more like a bound at that speed, completing up to three strides per second, with only one foot on the ground at any time and several stages when feet don't touch the ground at all. Hard, ridged foot pads and blunt, nonretractable claws maximize traction with the ground.
Because a cheetah's heart rate accelerates so quickly to achieve that speed, the cat can only maintain the chase for about 600 yards (550 meters) [source: Cheetah Conservation]. Then, it's too hot and too tired to run anymore -- at which point it becomes easy prey for a larger, more aggressive animal. A cheetah is so hot and winded at the end of a chase, it nears the point at which brain damage could occur [source: Blue Lion]. Cheetahs often lose their kill to a larger animal because they need to rest before eating.
That need to rest is one of the drawbacks of speed. Being the fastest animal on land can be a curse. Accelerating to 70 mph in several seconds puts serious strain on the heart, but there's more to it. The small, slender head and short muzzle that increase aerodynamics also means a cheetah has weaker jaws and smaller teeth than other predators. Cheetahs can't fight back if a larger animal attacks them or their young. If confronted, a roughly 125-pound cheetah will always run rather than fight -- it's too weak, light and thin to have any chance against something like a lion, which can be twice as long as a cheetah and weigh more than 400 pounds (181.4 kg) [source: Wild Habitat].
A cheetah's intense specialization for speed has taken its toll. Cheetahs' inability to defend themselves, along with habitat loss to humans, has shrunk the population so much that inbreeding has become a survival problem, too.
Once all over Africa, Asia and India, cheetahs now are limited to only small parts of Africa and Iran. The wild population has shrunk from 100,000 in 1990 to about 10,000 today [source: Defenders of Wildlife]. It's possible that cheetahs are an example of over-specialization -- such extreme adaptation for a single skill that a species no longer has the other skills it needs to survive. Overspecialization can result in extinction, and experts don't rule that out for cheetahs. The hope is that if cheetahs go extinct in the wild, conservation efforts will at least ensure their survival in captivity.
For more information on cheetahs and related topics, race through the links on the next page.
Both are spotted and swifty, but leopards and cheetahs have some major differences. Let us know if you can tell them apart at HowStuffWorks.
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More Great Links
- Cheetah. African Wildlife Foundation. http://www.awf.org/content/wildlife/detail/cheetah
- Cheetah. BlueLion.org. http://www.bluelion.org/cheetah.htm
- Cheetah. Defenders of Wildlife. http://www.defenders.org/wildlife_and_habitat/wildlife/cheetah.php
- Cheetah Adaptations: Running Speed. CheetahSpot. http://www.cheetahspot.com/speed.php
- Cheetah Conservation Fund http://www.cheetah.org/?nd=35