Insect Vibrations Tell of Good Times and Bad

Grab a branch of a young acacia tree crawling with appropriately named thornbugs and you just might utter an “ouch” at the sharp prick. The tiny horned insects will not hear your vocalization with ears, but rather as vibrations in the stem.

The thornbug (Umbonia crassicornis) is one of about 3,200 species in the treehopper family that, along with at least 200,000 other insect species, communicate by making the surface they live on vibrate, a method scientifically called substrate vibration.