Waggling HONEYBEES communicate. However, they will need dance lessons to do it properly.
In a castaway experiment, groups of young honeybees learning to forage on their own begin waggle dancing spontaneously — but badly.
Waggling is important. The rump-shimmy runs and turning loops of a honeybee encode clues that help her colony mates fly to food she has found, which can be kilometers away. However, in five of the new colonies, there were no older sisters or half-sisters to serve as role models for getting the dance moves right.
Nonetheless, as the children wiggled and looped day after day, the dances improved in some ways, according to behavioral ecologist James Nieh of the University of California, San Diego. However, when it came to waggling clues for distance information, Apis mellifera did not match the timing and coding in normal colonies where young bees practiced with older foragers before doing the main waggle themselves.
The youngsters-only colonies demonstrate that social learning, or the lack thereof, is important for communicating by dance among honeybees, according to James and an international team of colleagues in the March 10 issue of Science. Bee waggle dancing, like songbird or human communication, appears to be both innate and learned.
The dance may appear simple in a diagram, but performing it on vast expanses of honeycomb cells becomes difficult. Bees are “running forward at over one body length per second in the pitch black, trying to keep the correct angle, surrounded by hundreds of bees that are crowding them,” according to James.
Beekeepers and biologists are aware that some bees can learn from their peers — some bumblebees even tried soccer. However, “I think people have assumed it’s genetic,” James says of waggle dancing. That would make this fancy footwork more akin to the chatty but natural communication of cuttlefish color change, for example. The lab bee-castaway experiments, on the other hand, demonstrate a nonhuman example of “social learning for sophisticated communication,” according to James.
It took some intricate beekeeping to test for social learning. At an apiary research center in Kunming, China, researchers placed thousands of nearly mature honeybees (known as purple-eyed pupae) in incubators and then collected the newly emerged winged adults.
These kids were assigned to five oddly populated colonies of same-age worker newbies. Each colony was assigned a queen, who laid eggs but did not leave the colony to forage. Food had to come from the young team, with no older, more experienced foragers buzzing in and dancing around the flower locations.
Foraging bees must master not only the moves but also the obstacles of the honeycomb dance floor when waggle dancing. A cell could be empty. “It’s just the edges to cling to…. “It would be easy to make a mistake,” James says. Natural combs, in contrast to commercial hives with manufactured uniform honeycomb cells, “are very irregular,” he says. “They get a little crazy and rough around the edges.”
Dances on these perilous surfaces encode the direction of the food in the angle a dancer waggles across the comb (measured relative to gravity). The duration of the waggling bout indicates how far away the bonanza is.
In contrast to five other colonies in the apiary with a natural mix, the five castaway colonies were left to figure out dancing on their own. Researchers recorded and analyzed the first dances of five bees from each hive early in the experiments.
Even in the mixed-age hives, the dancers didn’t always get the perfect angle. A set of six waggle runs’ extremes may differ by more than 30 degrees. The castaway hives, on the other hand, had far more difficulty at first. In six repeats, two of the five castaway dancers’ angles were more than 50 degrees apart, and one poor bee strayed more than 60 degrees.
However, as the castaways gained experience, they improved. When the same marked bees were tested again a few weeks later, near the end of their lives, they angled around as well as dancers in a normal hive.
The castaways did not significantly alter dance features that encode distance to food. The hives had been set up so that all of the bees had the same experience of flying the distance to a feeder. Nonetheless, castaway bees continued to dance as if it were further away.
They gave more rump wags per waggle run (nearly five wags) than mixed-age hive bees (more like 3.5 wags). The kids also took their time on each run.
Evidence such as this foraging study is “in fact accumulating for the importance of learning (whether individual or social) in the complex behaviors of bees,” insect ecophysiologist Tamar Keasar of Israel’s University of Haifa writes in an email. She observes bees learning to extract food from complex flowers in her own work. After all, bees aren’t just little automatons with wings.
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