I know what you're thinking. The cheetah is the fastest animal in the world, right?

If you're talking about the fastest land animal, then yes, but there are many other animals that surpass the cheetah by wing and by fin, and even quite a few on land that come close.

So what could be faster than a cheetah? Let's talk about the fastest animals by air, by sea, and by land.



Fastest bird and fastest animal: Peregrine falcon

The fastest animal in the world is the peregrine falcon. When flying horizontally, like most birds do, these falcons are able to reach a mere 55 mph—which is still, by the way, faster than almost any other bird—but when they go into a dive, all bets are off.

The key to their speed is their deadly dive, in which they're able to exceed 200 mph by folding in their wings and plummeting at their prey with astonishing accuracy. To give you an idea of how fast 200 mph is, we can compare it to hurricane-level winds: in a category 5 hurricane (the deadliest kind), the strongest hurricane winds might reach around 200 mph (though most of them never reach those speeds). Now imagine going that fast while being able to aim, maneuver, and land on a target hurtling toward you from thousands of feet away.

Yeah.

Before diving, a peregrine falcon will fly to an altitude of over 3,500 feet and then bring its wings close to its body. During its descent, as its speed increases, one wing tends to be pushed forward, with its head tucked in to that side, while the other wing is pulled back. The tail and feet will be folded or tucked in, making the bird's body more aerodynamic and minimizing air resistance.

To manage these high speeds, peregrine falcons have special adaptations in their nostrils that allow them to breathe at such high speeds, and their eyes have special debris-resistant membranes, along with an extra gland to prevent their corneas from drying out.



Fastest fish: Black marlin

There's some controversy over whether the sailfish or the black marlin is the fastest fish in the ocean, but I'm going to put this debate to rest right now: at a top speed of nearly 80 mph, the black marlin actually beats the sailfish by nearly 15 mph. (Turns out there's a lot of misinformation out there.)

Okay, you may be wondering, but what makes black marlins faster than other marlins? For one thing, their bodies are deeper and have lower, more-rounded dorsal fins than blue marlins'. Their spears, which they use to slash prey, are also thicker and more robust than those of other marlins. Finally, their bodies are laterally compressed, rather than rounded, like in other marlins, making them more streamlined and helping them reach faster speeds.

Strangely enough, black marlins are the only marlin with rigid, non-retractable pectoral fins. Retractable fins reduce drag and save energy when a fish is trying to go fast, so the fact that black marlins are the fastest fish—yet don't retract their pectoral fins—has puzzled many fishermen over the years.



Fastest land animal: Cheetah

Cheetahs aren't the fastest animal in the world, but they are the fastest animal on land. They can accelerate from standing still to over 60 mph in just 3 seconds and can reach speeds of up to 75 mph.

Besides being extremely muscular, cheetahs have large nostrils that allow oxygen to be inhaled quickly, and their large heart and lungs work together to circulate oxygen more efficiently to aid in their speed. Cheetahs' long, flexible spines allow them to cover huge distances with each stride, and they vary their strides per second as they speed up, taking more strides per second as they run faster.

At top speed, cheetahs can go 23 feet in a single stride and can complete four strides per second. For comparison, the average human blinks once every four seconds—meaning that from one blink to the next, a cheetah could run 368 feet.

Cheetahs have small collarbones and vertical shoulder blades that are not attached to the collarbone, as well as hips that swivel on a flexible spine. These structural adaptations let them take longer strides, accelerate more quickly, and make sharper turns than other large cats. The tail acts as a rudder for quick turning, counteracting a cheetah's body weight, and the non-retractable claws add traction while they're running. The end result? Cheetahs are so fast, their feet actually spend more time in the air than on the ground.