REPRODUCED WITH PERMISSION, JAYNE YACK, JOURNAL OF EXPERIMENTAL BIOLOGY, DOI:10.1242/jeb.046805, 2011North American walnut sphinx moth caterpillars (Amorpha juglandis) look like easy meals for birds, but they have a trick up their sleeves—they produce whistles that sound like bird alarm calls, scaring potential predators away.
At first, scientists suspected birds were simply startled by the loud noise. But a new study presented at the International Symposium on Acoustic Communication by Animals in Omaha in July suggests a more sophisticated mechanism: the caterpillar’s whistle appears to mimic a bird alarm call, sending avian predators scrambling for cover.
“This is the first instance of deceptive alarm calling between an insect and a bird, and it’s a novel defense form for an insect,” says Jessica Lindsay, the study’s first author and a graduate student in the lab of Kristin Laidre at the University of Washington. “I think that’s pretty wild.”
When pecked by a bird, the caterpillars whistle by compressing their bodies like an accordion and forcing air out through specialized holes in ...