The hills are alive with the sound of – thornbugs. I’m Jim Metzner, and this is the Pulse of the Planet. A number of species of insects communicate with each other using vibrations transmitted through the plants that they live on.
ambience: male thornbug mating signals, individual young thornbug – or nymph- and group of young thornbug signals
Right now weâ€™re listening to the sounds that young thornbugs use to communicate with each other and their mother. Rex Cocroft is an assistant professor of biology at the University of Missouri. With the help of sensitive microphones, heâ€™s spent the last eight years eavesdropping on vibrating insects trying to unravel some of the mysteries of their communication.
“Thornbugs use sounds to communicate between the mother and her offspring. For example, the offspring communicate in the presence of a predator and the mother responds to that.”
If a mother thornbug is alerted that a predator wasp is in the vicinity, sheâ€™ll defend her young with her hind legs, hovering over the wasp until it backs off.
“Then after the predator has left, she communicates with the offspring.”
Once the thornbugs get a little older, theyâ€™ll produce different sounds, and use them for a very different purpose.
ambience: male thornbug
“And then when they become mature, they use a completely different set of signals. So, the way they locate mates is by using these signals. So males will produce often a very complex stereotype signal. And, in most of the mating systems of these insects, mating takes place by females on the plant, and there may be some kind of chemical signals, but the main way the male knows the female is on the plant if she answers his call with a very particular call of her own. Then heâ€™ll call again, and sheâ€™ll call again and theyâ€™ll duet back and forth until the male is able to locate the female.”
Weâ€™ll hear more on thornbugs in future programs. Pulse of the Planet is presented by the National Science Foundation. I’m Jim Metzner.