Honeybees waggle to communicate. But to do it well, they need dance lessons

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Honeybees waggle to communicate. But to do it well, they need dance lessons



In a castaway test setup, groups of young honey bees figuring out how to find their own food begin to spontaneously dance — but badly.

Waggling thing. The honeybee’s rump-shimmy runs and turning loops encode cues that help her colony mates fly to the food she finds, sometimes kilometers away. However, five colonies in the new test did not have older sisters or sisters around as models for getting the dance moves right.

However, the dances improved in some ways as the young flashed and twirled each day, reports behavioral ecologist James Nieh of the University of California, San Diego. But when waving the cues for distance information, Apis mellifera no patterns have ever matched the timing and coding in normal colonies where young bees train with older foragers before making the primary waggle themselves.

Only young colonies are showing social learning, or the lack thereof, is essential for communicating through dance in honey bees, Nieh and an international team of colleagues said March 10 Science. Bee waggle dancing, a type of language, appears to be both innate and learned, like songbird or human communication.

The dance may look simple in a diagram, but performing it in the vastness of honeycomb cells becomes difficult. The bees “run forward at more than a body length per second in pitch black trying to keep the right angle, surrounded by hundreds of bees crowding around them,” Nieh said.

Beekeepers and biologists know that certain types of bees can learn from others of their kind – some the bumblebees even tried soccer (SN: 2/23/17). But when it comes to waggle dancing, “I think people assume it’s genetic,” Nieh says. That would make the chatty but natural communication of the cuttlefish’s color change more like this fancy footwork, for example. Lab bee-castaway experiments instead present a nonhuman example of “social learning for sophisticated communication,” Nieh said.

The test for social learning took some elaborate beekeeping. At an apiary research center in Kunming, China, researchers placed thousands of nearly adult honeybees (at the so-called purple-eyed pupae stage) in incubators and then collected the newly winged pupae. adults when they appear.

These youngsters entered five oddly populated colonies of same-age novice workers. Each colony gets a queen, who will lay eggs but will not leave the colony to find food. Food needs to come from young workers, without older, experienced foragers whistling and dancing at flower locations.

In waggle dancing, foraging bees have to master not only the moves but the obstacles of the honeycomb dance floor. A cell can be empty. “It’s just the edges to stay on … It’s easy to trip over,” Nieh said. Unlike commercial hives that have uniform honeycomb cells, natural combs are “very regular,” he said. “On the edges, they get a little crazy and rough.”

A honey bee bringing food home to its colony does a spinning and waving dance that tells its colony mates how to find the source. In the center, a bee with a green dot on its back does its first waggle dance as other bees crowd around. He had followed the dances of other experienced foragers, so he was doing figure eights quite regularly. Bees without such mentors also don’t understand dance moves, a new study shows.

Dances on these deceptive surfaces encode the direction of food at the angle a dancer swings the comb (measured relative to gravity). The duration of the waggling bout gives a clue as to how far the bonanza is.

The five colonies of castaways were left to figure out the dance on their own, in contrast to the five other colonies in the apiary with a natural mix. In the first part of the experiments, the researchers recorded and analyzed the first dances of five bees from each hive.

Even with mixed-age hives, the dancers didn’t get the perfect angle every time. The extremes in a set of six waggle runs can vary by slightly more than 30 degrees. However, the castaway rash had more problems at first. Two of the five castaway dancers’ angles deviated by more than 50 degrees, and one poor bee strayed by more than 60 degrees in six repetitions.

Waggle dancing allows honeybees to share news about where to find food. The honey bee marked with a purple dot that makes an irregular figure of eight loops in the center has no older, experienced foragers around to lead her in the training dance. Because of this, his first dance is rough and the other bees seem to bump into him as much as follow him. A study comparing bees with and without a dance mentor suggests that this sophisticated communication is a mix of innate and learned behavior.

As the castaways gained more experience, they became better. Repeating the test on the same marked bees a few weeks later near the end of their lives found them angling as well as dancers in a normal hive.

What the castaways didn’t change much were the dances that encoded distance to food. The researchers set up the hives so that everyone had the same experience of flying the distance to a feeder. However, the castaway bees continued to dance as if it were farther away.

They produced more rump wags per waggle run (closer to five wags) than bees from mixed-age hives (more like 3.5 wags). The youngsters also took longer with each run.

Evidence like this finding “really stacks up for the importance of studying (whether individual or social) the complex behaviors of bees,” said insect ecophysiologist Tamar Keasar of the University of Haifa in Israel in an email. In his own work, he saw bees learning to forage from complex flowers. Bees, after all, aren’t just little automatons with wings.