Life as an insect generally involves following military-style discipline and adhering to a strict hierarchy when it comes to the division of labour and reproduction duties.
However it appears that bumblebees are much more flexible than once thought. They are not only there to serve the dominant queen.
New research published in Proceedings B of the British Royal Society shows that fertile female workers can be flighty: they often move to neighbouring colonies and are even capable of producing eggs.
Pierre Blacher and his colleagues from Sorbonne Paris Cite and the Universidade de Sao Paulo studied the behaviour of 665 individually marked bumblebees ( Bombus terrestris ).
The insects were presented with the choice of several small, artificial nests located on the roof of a laboratory building.
The scientists observed how around a third of the female drones visited a foreign nest — many visited several nests — and were able to remain in these neighbouring colonies without being attacked by the native bees or prevented from entering.
This preliminary discovery and subsequent drifting of fertile female workers to other colonies is dependent on their fertility and happens near the end of a colony’s life.
Competition between those capable of reproducing can be fierce and while it was found that non-drifting workers had no egg development, ovary activation could follow either isolation from the colony or drifting to another colony.
The biologists discovered that if they isolated groups of up to three female workers with different levels of reproductive capability from the colony, the insects began to create their own hierarchy whereby the oldest bumblebee became more fertile than the other two.
They noted that the most fertile bee was up to 20 per cent more likely to drift to another colony and after observing 40 bees that did drift, that they were also more likely to produce eggs in their new environment.
The likely purpose of the behaviour is to perpetuate the gene pool of a dying colony.DPA