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The Fastest Animal On Earth Is Not A Cheetah

It might be a falcon, a shrimp, or even the humble jellyfish. We go deep on the surprisingly complicated question.

What is the fastest animal on Earth?

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Did you say a cheetah?

You’re wrong.

For some reason, the idea that the cheetah is the planet’s fastest creature has hardened into fact through years of childhood repetition. But not all superlatives in the animal kingdom are so easily settled as weight (the blue whale) and height (the giraffe).

In fact, determining the fastest creature on earth is much more complicated than we’ve all been led to believe.

“When we talk about something being fast, it’s really not clear if you’re talking about the total duration, the total time it takes to perform the movement, the speed at which its performed, and the acceleration at which its performed,” said Sheila Patek, biologist and founder of Duke University’s Patek Lab. “Each one of these things mean very different things.”


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For instance, cheetahs are only “the fastest animal” if you restrict your search to land animals running from Point A to Point B. In which case, sure, cheetahs can hit speeds up to 29 meters per second (or about 64 miles per hour).

But even that figure requires a little context. Cheetahs run for a reason—to catch dinner—and most prey are smart enough not to bet their life on a drag race. Instead, they zig. Some even zag. And that means that while cheetahs are capable of reaching 29 m/s under ideal test conditions, in the wild they average only 15 m/s (33 mph) and maintain that speed for just one to two seconds. Yawn.

“They have a relatively low acceleration and thus take a long duration to achieve their impressive speeds,” said Patek.

Another animal often included in the “fastest” conversation is the sailfish. These large billed fish, in the same family as marlins and swordfish, have been known to reach speeds of about 30 m/s (68 mph) when they breach the waves, though like the cheetah their normal cruising speed is closer to half that. Still, these big-billed-beasts move so fast on a normal basis, they’ve evolved special tissues that heat up their eyeball nerves so they can process images at “race-car speed and precision.”

But neither land nor sea creature can hold a candle to the falcon, lord of air. When hunting, falcons climb to extraordinary heights and then use the force of gravity to plummet down toward prey like a meteor with talons.

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In one study, a gyrfalcon named Kumpan was found to accelerate to speeds between 52 and 58 m/s (~116 and 129 mph) after free-falling from a height of 500 meters (~1640 feet). Another experiment by National Geographic clocked a peregrine falcon at nearly 82 m/s (183 mph), though this bird was taxied up to 4,572 meters (15,000 feet) in a plane before its record-breaking dive.

Photo: Flickr user Andrea Pokrzywinski

Okay, so if we’re done shaming the cheetah, can we just crown the falcon in its place? Well, that depends on how you think about speed.

For example, you can look at the falcon’s impressive dive speed and forget that it took many seconds of climbing (either by wing power or by riding thermals) for the animal to reach a necessary height. That means falcons are capable of high speeds but relatively lame acceleration.

And if it’s acceleration you want, Patek has some speedy candidates. The mantis shrimp, for instance, has a spring-loaded, hammer-like appendage that it can cock and release like a crossbow. Once fired, the mantis shrimp’s Mjölnir hits home in less than three milliseconds. Translation: You could fit 90 mantis shrimp strikes into the time it takes a human to blink.

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Jellyfish boast an even faster acceleration. When one of these slimy sacks stings you, it’s actually launching billions of microscopic venom harpoons into your skin at velocities comparable to a bullet fired out of a gun. According to a paper published in Current Biology in 2008, each of these explosive cells, called nematocysts, can discharge in 700 nanoseconds or less and create an acceleration of more than 5 million times the force of gravity, or 5,410,000 g.

Nematocysts “clearly rule” in terms of highest acceleration in the shortest amount of time, said Patek. “But, in terms of a high acceleration-driven speed, trap-jaw ants and termite jaws are the most impressive.”

Trap-jaw ants are basically walking bear traps. Their mandibles ratchet open 180 degrees and then lock, relying on tiny sensory hairs to act like trip wires and tell the ant when to fire. According to Patek’s research, these mandibles close at speeds that reach 64 m/s (~143 mph). Best of all? When the going gets tough, this ant simply directs its weapon at the ground and lets the force of the mandibles ricochet it away from danger. Blastoff!

But even the power of the trap-jaw ant comes in second place to the bite of its arthropod cousin, Termes panamaensis.


Termite soldiers don’t have the luxury of open spaces. When they defend the nest, its often one-on-one in the confines of a dark tunnel, which is why they’ve evolved a bite that’s both fast and small—ideal for close combat.

First the termite flips over onto its back like a ninja. This positions the business end of its bite just below the invader’s head. Then it presses its mandibles against each other really hard until one jaw slides over the other so blindingly fast that both the biter and the bitten are flung backwards in the tunnel. Most invaders die instantly from blunt force trauma, but some stumble around for a few steps before dropping dead, apparently succumbing to the bug equivalent of the Five Point Palm Exploding Heart Technique.

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Jeremy Niven, a research fellow at the University of Sussex, measured the speed of this terrible termite deathblow back in 2008. Individual strikesexceeded 67 m/s (nearly 150 mph). “Since we published, no other group has published anything faster,” Niven confirmed via email.

So no matter how you slice it—top speed, acceleration, duration—the cheetah lags behind the competition for fastest animal on earth. The fastest animal movement belongs to the lowly little termite, the fastest cells to a jellyfish, and the fastest full-body move to a free-falling falcon.

But Patek would caution against closing the case file here. After all, these are only the fastest animals that we’ve taken the time to measure. Next year could bring in a whole new raft of contenders.