AUGUST
1989

 

 

 

By
Tom Turpin
 
Professor of
Entomology
Purdue University

 

 

 

 

 

8-11-89

Deceitful Buzzers

Buzzing is universally regarded as a warning sound. For example, buzzers remind us to fasten our seat belts. Buzzers in smoke detectors alert us that our houses are on fire or that the roast in the oven is slightly overdone. Elevators, airplane guidance systems and even computers buzz when things are amiss.

Buzzing as a warning signal was perfected by insects, especially the bees. The sound is produced by wing vibration as the insect flies. Most animals respond negatively to the buzzing of bees, and for good reason. Bees are equipped with a stinger they can use for defensive purposes. However, in most encounters with other animals, bees do not need to unsheath their stinger. Their buzz alone wards off most sources of potential danger.

So effective is the buzz of bees as a protective device that other insects have adopted it for their own use. Many flies, because their wingbeat frequencies are similar to that of the bees, sound like bees. The sound alone usually provides some protection for these imitators. However, when their color pattern matches that of bees, only an entomologist can tell the difference at first glance.

Some flies even mimic the aggressive behavior of disturbed bees. One group of flies that sounds looks and acts like bees even claim their mentor's name -- bee flies.

Not only flies have benefited from sounding like buzzing bees. One beetle, the green June beetle, is especially adept at convincing folks it is a dangerous insect. This is a large, somewhat flattened, green beetle with yellow body margins. As an adult, the green June beetle feeds on the foliage of fruit trees and on the ripening fruit. When these beetles appear in large numbers and swarm around during their feeding activities, many people have been convinced that they have encountered a swarm of killer bees. The beetle is perfectly harmless, but most folk, and other animals don't stay around long enough to find out.

Some might suggest insects that mimic the sound of bees are guilty of fraud or false advertising. But think of it this way, a little benevolent deceit can go a long way toward preventing encounters of the worst kind. At least from the insect's point of view!

 

Writer: Tom Turpin
Editor: Carol McGrew