This acrobatic spider flips for its food — literally

A leap-and-lasso combo lets the Australian ant-slayer spider nab insects twice its size

A banded sugar ant caught by an Australian ant-slayer spider

This banded sugar ant didn’t stand a chance once it was lassoed by an Australian ant-slayer spider.

A. Aceves-Aparicio

Move over, Spider-Man. One tiny Australian spider has its own secret superpower: somersaults. And it uses that skill to take on ants twice its size.

Ants are dangerous prey. They’re armed with powerful jaws and sometimes chemical weapons. Fewer than one percent of spiders try to hunt this risky food. But high-speed footage now shows how the Australian ant-slayer spider (Euryopis umbilicata) does it. They leap over their victims, lassoing them with silk.

The hunting maneuver hasn’t been found in any other spider species. Researchers reported it September 19 in the Proceedings of the National Academy of Sciences.

“This acrobatic behavior is just fascinating. I’ve personally never seen this kind of hunting,” says Paula Cushing. She’s an evolutionary biologist and curator of invertebrate zoology at the Denver Museum of Nature & Science in Colorado. She wasn’t part of the new study.

Alfonso Aceves-Aparicio stumbled across the somersaulting spiders while walking home one night. He noticed dark dots darting across the pale bark of a eucalyptus tree. At the time, he was a graduate student at Macquarie University in Sydney, Australia. Now he’s a behavioral ecologist at the Max Plank Institute for Chemical Ecology in Jena, Germany.

Intrigued by the dots, Aceves-Aparicio looked closer. He saw they were tiny spiders moving among ants. Suddenly, one of the spiders jumped. “I thought it was trying to escape an ant,” he recalls. “But then I saw the ant floating and I thought — woah, there’s something going on here.”

Ant-slayer spiders capture ants by somersaulting over them and tagging them with a thread of silk (shown here in real time, then slow motion). The leap takes just a few milliseconds. The spiders then dart around their victims to trap them in more silk and sweep them off their feet.

To see what was happening in greater detail, Aceves-Aparicio borrowed a high-speed camera. He used it to slow the action down. His footage showed that the spiders were hunting the ants — in a completely unknown way.

Most ant-hunting spiders use webs or sneak up on their prey from behind to minimize risk. Not these spiders. Despite being smaller than their prey, they faced banded sugar ants (Camponotus consobrinus) head on. Each spider positioned itself so that it could watch ants as they moved up the tree. As one approached, the spider flipped above its prey. Once in the air, the spider latched a thread of silk onto the ant.

This tethering action took just milliseconds. And it alone determined whether the hunt would succeed. If the tether stuck, the spider then darted around the ant, deftly wrapping it in more silk. Then it yanked the ant off its feet and dragged it off to eat. 

What stands out to Aceves-Aparicio and his colleagues was how well the method worked. Predators like lions and wolves tend to miss around 50 percent of their intended targets. The researchers filmed 60 spider hunts. The arachnids’ success rate? A staggering 85 percent.

To Aceves-Aparicio, the discovery shows that extraordinary behaviors can hide in plain sight. “The message here is to have a little curiosity and to pay attention,” he says. “There are things going on everywhere. We just have to be there to find them.”  

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