The glassy-winged sniper is such an impressive insect when it urinates that it could inspire more efficient designs for waterproof devices.
Saad Bhamla was in his orchard in Atlanta, Georgia, when he first noticed the feat. The sniper forms clean, round pee drops that he spews out at lightning speeds. Bhamla, a Georgia Tech assistant professor of biomolecular engineering, pulled the iPhone out of him to take some slow-motion videos.
“The closer I got, the more I realized that I was doing something interesting,” says Bhamla. the edge.
“The closer I got, the more I realized that I was doing something interesting”
It turns out that the sniper achieves something with his urine that hasn’t been documented in a biological system before: a phenomenon called superdrive. How the sniper does this is detailed in a research work Bhamla and his colleagues published this week in the journal nature communications. And it could also help humans figure out how to superdrive, not with urine but with smartwatches and other devices that dry themselves.
Simply put, superdrive allows a stretchy object to fly at speeds faster than the thing throwing it. Precise timing between the soft object and its catapult gives the object a boost of energy. To understand this phenomenon, think of an Olympic diver, Bhamla explains. A skilled diver could time a jump to get the maximum resonant energy from the springboard.
After taking the videos with his iPhone, Bhamla and his colleagues turned to high-speed cameras and microscopes to get a closer look at the sniper. What they found was an anal stylus, also known as a rear flicker, which is key to the unique way the insect goes about business. The rear flicker is moved back to make room for the incoming urine, allowing it to form a droplet at the end of the insect’s tail. At the same time, the blinking compresses the droplet, allowing energy to build up through surface tension.
Once the drop is the right size and shape, the blink rotates back another 15 degrees. So that shake the drop like a pinball. The rear flash is incredibly fast, accelerating over 40G, which is 40 times faster than the acceleration of a running cheetah. What’s more surprising is that urine flies at an even greater speed than butt flicker, the telltale indicator of superdrive.
As an added bonus, the tactic is also energy efficient. After all, the blob is moving faster than the catapult that launches it. Snipers actually pee this way to save energy because they pee a lot. Snipers will drink and urinate volumes of up to 300 times their body weight a day because they are on a super low calorie, nutrient deficient diet of plant sap. And she has to squirt her urine to keep the drop from sticking to her like a drop of maple syrup.
What does this have to do with a smart watch? The Apple Watch’s Water Lock feature, for example, can now expel water from the device after swimming. But as far as Bhamla knows, devices like this don’t use superdrive yet. If engineers can learn from the sniper, they could design more efficient water ejection systems for the devices. That way, you can also keep your watch dry and charged for longer. The same kind of technology could be used in hearing aids or anything else you want to make waterproof.
Bhamla and his team tested sniper tactics by bouncing water off speakers on kitchen tables. They used the vibration of the speakers to compress small droplets, creating surface tension. With precise timing, they could launch the blobs at high speeds.
While it sounds fitting, this useful trick isn’t what earned the insect the nickname “sharpshooter.” It is mostly known in the US as a parasite to farmers. Their bite marks may appear like little bullet holes on the leaves and can transmit diseases from one plant to another. Their copious urine can also bleach fruits.
Bhamla hopes that his research can inspire more people to look at insects in new ways. “I think it will get kids young at heart and old to go out to their backyards and watch and enjoy,” she says. the edge. “It’s a lot of fun. That’s good enough for me.”