World's fastest land animal is NOT the cheetah
A mite no bigger than a sesame seed leaves the cheetah in its dust — if you're measuring speed by body lengths per second.
Tue, May 06, 2014 at 04:41 PM
The cheetah is most often referred to as the world's fastest land animal — and that's the truth if you're measuring by miles per hour. But that's not really a fair measurement when you take the size of an animal into consideration.
For a more accurate measurement relative to body size, researchers also consider body lengths per second. And by this metric, the competition isn't even close. The cheetah gets left in the dust, by a landslide.
That's right, the rightful title holder for the world's fastest land animal is not the cheetah, reports Wildlife Extra. Rather, the title belongs to an animal no bigger than a sesame seed: Paratarsotomus macropalpisis, a tiny mite found in Southern California.
The mites were clocked by California undergraduate college student Samuel Rubin, who spent last summer setting stop watches on these remarkable bugs. He found that the mites could traverse up to 322 body lengths per second, which is the equivalent of a person running at roughly 1,300 miles per hour! By comparison, a cheetah running at 60 miles per hour only reaches 16 body lengths per second.
In fact, the cheetah isn't even in the conversation when considering speed by body lengths per second. Second place belongs to a beetle, which runs at 171 body lengths.
"It’s so cool to discover something that's faster than anything else. Just to imagine, as a human, going that fast compared to your body length is really amazing," said Rubin. "But beyond that, looking deeper into the physics of how they accomplish these speeds could help inspire revolutionary new designs for things like robots or biomimetic devices [using an imitation of elements of nature to solve complex human problems]."
Rubin’s advisor, Jonathan Wright, professor of biology at Pomona College in Claremont, California, first suggested measuring the mites' speed after studying the effect of muscle biochemistry on how quickly animals can move their legs.
"We were looking at the overarching question of whether there is an upper limit to the relative speed or stride frequency that can be achieved," said Wright. "When the values for mites are compared with data from other animals they indicate that, if there is an upper limit, we haven't found it yet."
In other words, the true Flash of the animal kingdom may still be out there. For now, though, Paratarsotomus macropalpisis is the lone title holder. The team had to make use of high-speed cameras to observe the lightning-quick mites in action.
"It was actually quite difficult to catch them, and when we were filming outside you had to follow them incredibly quickly as the camera’s field of view is only about 10 cm across," explained Rubin.
Speed isn't the only superpower that these mites possess. They have also been found running on concrete that reaches temperatures as high as 140 degrees Fahrenheit, which is significantly higher than the upper lethal limit of most animals. They can also stop and change direction extremely quickly. Researchers hope that studying how the bugs accomplish these incredible feats will lead to new insights into potential bioengineering applications.
Related on MNN: