Image of the Day: Whistling Caterpillar

Nessus sphinx hawkmoth larvae make alarm calls using mechanics similar to rocket engines. 

The Scientist Staff and The Scientist Staff
Mar 1, 2018

Nessus sphinx hawkmoth larvae make alarm calls using mechanics similar to rocket engines. JAYNE YACK

When they’re threatened by a predator, the larvae of Nessus sphinx hawkmoth caterpillars (Amphion floridensis) produce a high-pitched “whistle” by forcing air out of their mouths. Researchers reported the finding on Monday (February 26) in the Journal of Experimental Biology.

“This is really remarkable, considering that caterpillars are not considered to be ‘acoustic’ insects,” study coauthor Jayne Yack, a neuroethologist at Carleton University, says in a press release. “We have discovered four completely different ways that they make sounds.”

See “The Caterpillar that Cries Wolf

By analyzing sound waves, the researchers deduced that the caterpillar produced the vocalizations by forcing air through a tight space between its crop, a part of the throat where it packs food to eat later, and its esophagus, similar to blowing air across...

C.A. Rosi-Denadai et al., “Vocalization in caterpillars: a novel sound-producing mechanism for insects,” J Exp Biol, doi:10.1242/jeb.169466, 2018.