Humans may have taken over the Earth, but frankly we’ve nothing on the abilities of others kinds of life on the planet.
Take the mantis shrimp, which lives in the warm waters of the Indian and Pacific oceans: these colorful crustaceans (which are actually cousins of lobsters, not shrimp), have the ability to see underwater colors beyond anything we can imagine. They also have the animal equivalent of tiny boxing gloves, called dactyl clubs, that are capable of punching through the shells of crabs or snails. Their clubs reach speeds up to 50 miles per hour (80 km per hour), so fast they create shockwaves through the water.
It’s a feat of force we humans can barely comprehend. It’d be like a 150 lb (70 kg) person generating 375,000 lbs of force in just a fraction of a second. The acceleration of the mantis shrimp’s clubs is often compared to that of a bullet fired out of some rifles, but bullets can only be fired once; mantis shrimp use their clubs around 50,000 times per molt, when they get new ones.
For years, scientists assumed these creatures must have had some unbelievably strong muscle to make the clubs work. But Sheila Patek, a biologist at Duke University, suspected there was something else at play. Back in the early 2000s, she and her team (then at University of California-Berkeley) took high speed-footage of mantis shrimp punches. Patek realized that the mantis shrimp doesn’t have meaty muscles at all. Instead, they use part of their exoskeletons as a spring that they can load up and release.
Since that work was published in 2004, the team noticed loads of other animals capable of generating similarly fantastic feats of acceleration. There’s the South American trap jaw ant, which can snap its mouthparts together at speeds reaching 140 mph in the blink of an eye. There are frogs and locusts that go from sitting to moving 10 mph in hundredths of a second. Chameleons that can shoot out their tongues at about 11 mph in a tenth of a second. Even plants like the Venus flytrap and the aquatic bladderwort, microbes like hydra, and certain fungi are capable of incredible accelerations as they snap and suck prey, or shoot out spores.
Patek and colleagues from a number of institutions started wondering: what if there was a trait shared by all of these creatures? In a study published today (April 26) in the journal Science, they propose that springs similar to those that propel mantis shrimp clubs are found all over nature, and explain how life all over the planet is capable of accelerations that shouldn’t be possible.
They looked at examples of over 100 different species to see if this theory held up. They found that many animals, plants, and fungi have adapted springs, rather than muscles, to generate repeatable acceleration power. Muscles generate force by contracting, but can only do so up to a certain speed. They also take up space and energy smaller creatures don’t have (spring-powered creatures are all small—frogs are about as big as they get). Springs, on the other hand, are capable of compactly storing energy and releasing it swiftly.
Beyond providing an explanation for all kinds of biology, this study could improve future robotic capabilities. At the moment, though robotics has taken several leaves out of nature’s book, nothing we’ve ever built is capable of anything like a mantis-shrimp punch. “Biology continues to outperform engineering at these calculations,” says Patek. This work could help bridge that gap, and hopefully engineers will use it for good.