insects that yell

I'm pretty sure I've previously linked to the moths that scream at bats to make them go away, except of course they're not actually Doing A Screm: they're vibrating membranes on their abdomen.

I mentioned this to simont the other day, and he went "wait they scream?" and I was forced to add the disclaimer above... and then I poked the internet and found, uh, Vocalization in caterpillars: a novel-sound-producing mechanism for insects:

Insects have evolved a great diversity of sound-producing mechanisms largely attributable to their hardened exoskeleton, which can be rubbed, vibrated or tapped against different substrates to produce acoustic signals. However, sound production by forced air, while common in vertebrates, is poorly understood in insects. We report on a caterpillar that ‘vocalizes’ by forcing air into and out of its gut.