Waggle Dance Of Honeybees Is No Longer Useful In Some Cultivated Landscapes

For bees and many other social insects, it is vital to be able to exchange information for the success of their colony. There is one way by using which honeybees do this. This is a unique pattern of behavior, which probably evolved more than 20 million years ago. The waggle dance of a bee informs its sisters in the colony where to find a high-quality source of food. However, in current years people have begun to examine the actual advantages of this dance language. The biologists of the University of Lausanne in Switzerland and of Johannes Gutenberg University Mainz (JGU) in Germany have now shed some limelight on the advantages and disadvantages of the bee dance. A behavioral ecologist at Mainz University, Dr. Christoph Gruter said that to their surprise, they found that bee colonies are more successful in collecting food if they are deprived of their dance language. One possible cause may be human-induced habitat change. Together with his colleagues in Lausanne, Grüter examined experiments over many years to study what effect the dance language has on the success of the colony.

There are about ten different species of honeybees which are communicating through waggle dancing. However, the vast majority of bees which is more than 500 species of highly social stingless insects, have no dance language. Therefore, Grüter was interested in the advantages the waggle dance brings to colonies, not least because, as a communication strategy, it is relatively time-consuming. Some waggle dances may last only a few seconds, while others may take up to five minutes.

In the examinations, the scientists modified the conditions influencing many of the bee colonies to confuse and, as a result, disorientate the dancing bees. Performed under such conditions, the waggle dance no longer made any sense to its bee audience. To make these conditions, the light was prevented from falling on the honeycombs. Also, they were turned into a horizontal position, avoiding the bees from using gravity to orientate themselves. Another particularly significant aspect was to take into account their capacity to memorize the location of food. Gruter said that bees foraging for food have an excellent memory and can recall a rich feeding spot for several days. Therefore, the research team had to avoid foragers which are performing the waggle dance for 18 days to make sure that they could not use their memory to tell other bees where to fly to find the excellent sources of food. Foraging bees are older than other colony members. In their final stage of life, they no longer work in the hive. Instead, they go out for collecting nectar and pollen. Typically, they are in the last 18 days of their lifetime.

The biologist's team was astonished by their result which shows that beehives without the dance information were more active and produced more honey than beehives which used dance language.

By: Preeti Narula

Content: https://www.sciencedaily.com/releases/2019/02/190222101225.htm