Notes

It can reach a speed of up to 75 miles per hour and can go from 0 to 68 miles per hour in under three seconds.
Which sports car am I talking about?
None. I am talking about the cheetah, which is the fastest land animal in the world.
The cheetah has many special adaptations that help it to run fast. An adaptation is something that helps an animal to live in the wild. Adaptations might help animals find food, get away from danger, or find mates. In the case of the cheetah, its body has adaptations that make it very fast. Cheetahs use this super speed to hunt and catch their prey.
One of the cheetah's special adaptations is its claws. If you have ever looked at a cat's paw closely, you might have noticed that the cat can retract* its claws. A cat puts its claws out when it wants to use them for scratching or climbing. When the cat is done using its claws, it can retract them back into its paws. A cheetah cannot fully retract its claws. This means that a cheetah's claws are always out. This adaptation gives the cheetah a better grip when it is running. The un-retracted claws act just like the treads on a car's tires or cleats on a track shoe. This extra grip helps the cheetah to run faster.
Another important adaptation for the cheetah is its long tail. A cheetah's tail acts like the rudder on a boat. In other words, the tail helps the cheetah to steer as it runs. Even when a cheetah is running at top speed, its tail helps it to change direction in an instant. The tail allows the cheetah to take sharp turns without slowing down or losing its balance.
Cheetahs weigh much less than other big cats. They have small heads, thin legs, and short muzzles (noses and mouths). These smaller features help the cheetah to be more aerodynamic. Something that is aerodynamic has a shape that allows air to pass over it easily. The more easily air can pass over something, the faster it will go. A cheetah's small head and flat face are very aerodynamic. This means that air passes over them effortlessly, allowing the cheetah to reach top speeds with ease.
Cheetahs' bodies also have a few adaptations that help it to breathe in and use more oxygen. The large nostrils on a cheetah's nose help it to take in more oxygen as it runs. Cheetahs also have very big lungs that allow it to breathe very deeply, bringing a large amount of oxygen into its body. A cheetahs' large heart can then pump the oxygen-filled blood throughout its body very quickly as the animal runs.
These adaptations help the cheetah reach speeds of over 70 miles per hour in only a few seconds. However, they also can cause some problems. A cheetah cannot keep its top speed up for very long—it can sprint, but it is no good at distance running. After a one to two minutes of running at maximum speed, the cheetah must slow down and rest, often for up to 30 minutes. This means that if the cheetah did not catch its prey, it must wait before it can try again. By the time the cheetah is ready to run again, the animals it was hunting might be very far away.
Similarly, the cheetah's aerodynamic body allows it to run fast, but it also makes the cheetah less able to defend itself in a fight. The cheetah is much smaller than other predators. Lions, for example, can weigh over 400 pounds—about 275 pounds more than a cheetah. Cheetahs also have smaller teeth and a weaker jaw. If a larger animal threatens a cheetah or tries to take its food, the cheetah has no choice but to run away.
Even though the cheetah is the fastest animal on land, it is still in danger. In 1900, there were 100,000 cheetahs in the wild. Today, there are only about 10,000. The fact that they cannot fight off larger animals is only a small part of the problem. Cheetahs face much larger problems because of human beings. Much of the cheetah's land is being turned into farmland or housing for growing cities. Cheetahs are also being hunted for their fur or trapped and sold as pets for the very rich. We may not be able to help cheetahs by making them stronger or giving them bigger teeth, but we can help them by protecting the animals and their land.

*retract (verb): to draw back or in.