Lasers Detect Insect Roar That Humans Couldn't Otherwise Hear — Listen

Lions roar. Gorillas roar. Insects roar.

One of the types of bugs that was found to exhibit roaring behavior. (Image source: Sanchez JA, Spina ML, Perera OP, Creative Commons License)

That last one might sound like an oxymoron, but scientists recently discovered that some insects do in fact roar even though humans can't hear it without assistance.

New Scientist reported that two species in the insect group of mirid bugs were found to exhibit this behavior by Valerio Mazzoni's team at the Edmund Mach Foundation in Italy. Here's how:

The team found that when two males were introduced on the same leaf, they seemed to compete in roaring duets. When one insect heard a roar, it always sounded its own, apparently in response. This suggests that, as in big cats, the roars might serve to establish dominance or attract females. Female mirids don’t seem to roar.

But unlike the roars of big cats, the sounds produced by bugs are transmitted through the solid material beneath their feet, usually a leaf, rather than by the vibration of air molecules.

Thousands of insect species communicate through such vibration, but these roars are unlike any other known insect noise.

"When you listen to these sounds through headphones you’d think you were next to a tiger or lion," Mazzoni told New Scientist.

Hear the roar detected with a laser vibrometer:

What's also special about the roar of the mirid bugs, New Scientist pointed out, is that there's no leg or wing rubbing to produce the noise.

"It must be a specific organ in the abdomen producing the roars," Mazzoni told the publication, noting that he hasn't found the source yet. 

The study about this discovery was published last month in the Journal of Insect Behavior. The study authors wrote that they believe the roar is part of the insect's mating behavior.