New Dancer in the Hive; an Insect Imposter Helps Scientists Decipher Honeybee Lingo

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New Dancer in the Hive

A bee or not a bee? That is the question. The answer: It's not a bee at all. But members of the hive can hardly tell the difference. That's why entomologists express such excitement about recent experiments with a European robot honeybee.

Ever since German researcher Karl von Frisch first documented in 1921 that honeybees perform a "waggle dance" to communicate with one another, scientists have dreamed of creating a mechanical bee that could imitate the insects' carefully choreographed behavior. The naturalist J.B.S. Haldane, a contemporary of von Frisch, suggested fruit growers might someday use fleet-footed model bees to tell hivemates the location of trees in need of pollination. And entomologists have long sought a mechanical bug-that-can-boogie to help them decipher the bee's complex dance language, which biologists generally consider one of the more sophisticated systems of symbolic representation in the entire animal kingdom.

But the honeybee six-step is not easily imitated. Previous experiments using mechanical bees only angered hive residents; they would gang up on the intruding model and plaster it with stings.

Now, however, researchers have savored sweet success.

The accomplishment, described this past June in the German journal NATURWISSENSCHAFTEN, has entomologists abuzz. A team led by bioacoustics researcher Axel Michelsen of Denmark's Odense University and entomologist Martin Lindauer of West Germany's Wurzberg University has made a computerized bee that performs bee-dance steps properly enough to convince its live sisters it knows what it's talking about. When the researchers program the model to dance a message indicating it has found food 1,000 meters to the southwest, hivemates fly off to that exact location. When they reprogram it to signal a different direction and distance, new recruits go directly to the new destination.

The computer-manipulated brass pellet, coated in beeswax, is "a gold mine," says Gene E. Robinson, a bee specialist at the University of Illinois at Urbana-Champaign. "This is the kind of thing where a technical advance is going to open up a whole lot of biological avenues."

Honeybees use the waggle dance primarily to communicate the direction, distance and quality of food sources. With U.S. farmers paying beekeepers more than $30 million annually for use of their hives to pollinate crops valued at $9 billion, one might suppose the robot bee's developers have a strong interest in using their creation to direct hoards of honeybees to selected locales. Not so, says Michelsen. Robobee's real purpose is far more interesting--and considerably more esoteric--than that of high-tech honey gatherer. The device provides scientists their first opportunity to dissect the honeybee's complex language -- a language that researchers now understand just well enough to crudely mimic with their model, but which still holds many mysteries. By programming their model to perform different dances and observing the effects on surrounding bees, researchers hope the robot bee will serve as a sort of Rosetta stone for the honeybee tongue.

"The scientific purpose of all this is to find out what is the language--what's the code," Michelsen says. "There's a long list of possible signals within these dances, so we would like to know which ones are used by the bees."

Scientists have learned a lot by simply observing bees but have had difficulty discerning which aspects of the dance convey real information. The model bee should facilitate that investigation, Michelsen says, by allowing the researchers to mix and match elements of different bee dances. "We jsut change a few lines of the program and create dances that the bees would never do themselves. Then we see how they respond."

Donald R. Griffin, an entomologist at the Rockefeller University in New York City, puts it in terms almost reminiscent of the movie "Close Encounters of the Third Kind," in which humans use a simple musical progression in their attempt to commune with extraterrestrial beings. …