Nature Video

This is the moment a group of social sawflies banded together in a strange but effective defense method.

By interlocking, the tens of sawfly larvae appeared much larger than they would be alone; they then wiggled in unison as to appear as one organism.

Pic by Aaron Pomerantz / Caters –

This behaviour was witnessed by integrative biologist Aaron Pomerantz, who spotted the group of sawflies in Tabopata, Peru, last month.

In his video, Aaron, 27, who is a PhD student at UC Berkeley, California, USA, first shows the sawflies while they are static.

He then moves his camera, though, causing the sawflies to wriggle frantically – something that would be enough to make a person or creature jump

Aaron said: “It certainly caught me by surprise!”

“From what I can tell, collective behavior likely evolved in order to incur a survival advantage.

“One lone sawfly might be quickly picked off by a hungry bird or spider, so being in a large tight-knit group could help them survive attacks.

“By moving in unison like this, perhaps they appear to be a larger animal, which could scare off a would-be predator.”

Pic by Aaron Pomerantz / Caters

Aaron said his video has received two main responses: intrigue and disgust.

Most people, he said, are fascinated, as they have never seen this kind of behaviour before.

Aaron, who filmed the insects on August 26, said: “I had never seen anything like this, and was totally shocked.

“I tapped on the tree and was blown away by their collective defensive behavior.

“I also made some noises at the group, but they seemed to respond more dramatically to me breathing on them and vibrations from my hand.

“I’ve been making field expeditions to the Amazon rainforest for over two years now, and every time I go I still see something new and interesting, like these sawflies.

“You never know what you’ll find in the most biodiverse region on the planet.”