dancing bees

Honeybees can communicate with others from far-off continents by learning to interpret their moves.

Bees translate dances of foreign species

· Mixed hives learn to interpret signals
· Movements point out distance of food source


Honeybees can communicate with others from far-off continents by learning to interpret their dance moves, scientists have found.

The world's nine species of honeybee separated about 30m years ago and have since developed their own diverse dances, which are used like languages.

One of the most important moves is the waggle dance, which foraging honeybees use to tell workers back at the nest how far away and in which direction they will find a new source of nectar. In the dance, bees shake rapidly from side to side as they move forward, before looping around and starting again.

As the bees perform, they warm up and release chemicals that are thought to cause nearby worker bees to pay attention and then follow the directions encoded in the moves.

A team of researchers from Australia, Germany and China decided to investigate whether bees from different continents could understand one another. To do so, they established a hive of the two most geographically distant honeybee species, the European and Asian honeybee.

Using high-speed video footage of the bees in their natural environment, the scientists were able to spot how the dances differed. Both used the same tactic to indicate direction. If bees of either species danced while pointing their head upwards, it meant fly towards the sun. Pointing downwards meant fly away from the sun. By changing their position relative to gravity, they could direct worker bees to fly in any direction necessary.

But the honeybees differed in how they danced out distance. In both species, longer dances indicated that food was further away, but Asian bees danced much longer to indicate the same distance. To European honeybees, a 1.5 second dance meant the food was 600 metres away, while Asian bees understood this to mean 400 metres.

In an experiment set up along the banks of the Da-Mei canal in Fujian province, China, the scientists trained European honeybees from the hive to visit one of six feeding stations, which contained dishes of sugary liquid. The stations were set at 400, 500 and 600 metres in front of and behind the hive. The bees then returned to the hive and danced out directions so worker bees could find where to feed.

Video footage showed that when the foragers returned and began dancing, other bees watched and later left the hive in search of the food. "At first, the Asian bees did not turn up, but later they found the right feeder," said Jürgen Tautz, a co-worker on the study and head of the bee group at the University of Würzburg in Germany. The research is published in the journal PLoS One.

The team then trained the European bees to visit a different feeding station and again let them return to the hive to dance out its location. "The second time around, the Asian bees turned up immediately. They had learned that the distance was different in these dances and recalibrated how far they had to fly."

The finding is the first to suggest that honeybees can learn to understand the dialects of other bee species.

"We believe that this is an important breakthrough in the study of honeybees, and that such mixed-species hives will open exciting new avenues of research into various aspects of this social insect's biology," the team wrote.

The scientists are conducting experiments to see if European honeybees are just as able to learn the dances of Asian honeybees. The importance of bee dances was first noted by the Austrian zoologist Karl von Frisch, who was awarded the Nobel prize for medicine in 1973.

* Ian Sample, science correspondent
The Guardian-Wednesday June 4 2008

HERE