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			Prisoners of take-over treat Cape bees like royalty. Carrie Straight 05.25.01 In the world of honeybees, there is a caste system made up of queens and workers. In a colony, the queen is usually the only female that lays eggs. She lays one egg in each cell, which the workers add food to and close up. The workers feed more food to the larvae that will be queens. They also feed them a substance called “royal jelly”. Royal jelly is a highly nutritious secretion from the workers' glands. The workers feed less food and no royal jelly to larvae that will become workers. Because of the honey trade, Cape honeybees (Apis mellifera capensis) are now all over the world. Researchers thought that the African honeybee (A. m. scutellata) might be aggressive and take over nests of the Cape honeybees. They found the exact opposite. The Cape honeybees take over African honeybee hives, kicking out the queen. The Cape worker bees then start laying eggs and the normal caste system breaks down. But what is the benefit for Cape workers to take over another bee species's hive? Researchers wanted to answer this question. They placed Cape eggs in a European beehive (hybrid A. m. carnica and A. m. mellifera) and placed European eggs in a Cape hive. They let the bees take care of the eggs until they capped the cells. Then they placed the comb (with the larvae and food enclosed in their cells) in an incubator. They measured each bee when it emerged from its cell and compared the native bees and the foreign bees. From this study, the researchers found out that European workers fed the Cape larvae more than their own larvae and more than the Cape larvae would normally get when fed by Cape workers. This created Cape adults that were more like queens than normal. By taking over another species's hive, Cape workers might be able to rise above their ranks in bee society and produce “pseudo-queens”.


			Beekman, Madeleine, Johan N. M. Calis, and Willem Jan Boot. 2000. Parasitic honeybees get royal treatment. Nature 404: 723.