The Paper's reporter Lu Xinwen
Male patchpods with "super" claws – tiny shrimp-like crustaceans – arguably one of the fastest and most dynamic life forms on Earth. The researchers found that the crustacean could repeatedly close its paws in less than a millionth of a second, producing high-energy water flows and thumping sounds. The speed of their claws is so fast that it almost violates the laws of physics. On February 9, the paper was published in Current Biology, a journal owned by Cell Press Cell Press.
Senior author Sheila Patek, a professor of biology at Duke University in the United States, said: "What is really surprising about these footed animals is that they 'wander' on the boundaries of our cognition, that is, these little things can move so fast without self-destructing. If they go a little faster, their bodies will fall apart. ”
Although footed animals are athletes, they are inconspicuously long-lived. They are small— only a few millimeters long — and they thrive in icy water and feed on dead algae and other flora and fauna.
"They're hard to see with the naked eye, but when you put them under a microscope, you see movie scenes like 'New York City of Seaweed,' where these little creatures interact and move in a variety of ways." Patek said, "It's like something that jumps out of the world of movies. ”
Measuring the acceleration of such a small, fast object is not an easy task. The researchers used a highly specialized hyper-speed camera and hung a human hair in front of them to lure the aggressive crustacean to scratch.
"We put a lot of effort into capturing this movement. We couldn't do it in the field because the equipment was too expensive and too professional – basically the 'Maserati' of the camera world. Once we can capture the picture, we can see that when they shoot hard, a jet of water is created. ”
These water jets often lead to cavitation phenomena, where bubbles form due to rapid changes in water pressure. When these bubbles burst, they release a lot of energy, large enough to degrade the steel used in the ship's propellers. Don't underestimate these small bubbles, they can not only reduce the efficiency of the machine, produce shock waves, and the force generated when they rupture can even "explode" small holes in the surface of the metal in contact with them.
"Cavitation is a very powerful effect. This is one of the most active events on Earth. Patek said. It's remarkable that these tiny creatures can cause this phenomenon. ”
Although researchers were able to quantify the mechanism of bites in foot-footed animals, why they did it remains a mystery.
"Their claws make up 1/3 of the male's body weight." Patek said, "We want to know why they are investing so much in this kind of behavior, is it because of male-female interaction or territorial disputes?" That's what we want to figure out. ”
The researchers also hope to explore how creatures such as footpods push physics to the limits, which could provide inspiration for engineers and designers.
"There is a two-way street between engineering and biology. Sometimes we find things in nature that engineering can't do, and sometimes engineers help us figure out how something works in nature. "It's important to think about design from an evolutionary perspective, and life has millions of years to adapt." ”
Editor-in-Charge: Cui Xuan