THURSDAY, 10 AUGUST 2006
Dr Adrian Dyer and colleagues from Cambridge University, working with Professor Lars Chittka of Queen Mary College at the University of London, argue that the plants try to produce 'warmer' flowers to encourage bees to visit. Their paper was published in last week's Nature.
In the team's key experiment two sets of flowers, of different colours, were kept at two different temperatures. Bees were allowed to sit on the flowers of their choice. The bees have a preference for warm nectar and infallibly identified the warmer set of flowers.
However, the preference disappeared if both the sets of flowers were the same colour or if the two sets were kept at the same temperature. This suggests both that the bees have a preference for warmer flowers, and that they associate this with colour.
Bees are already known to associate the colour of the flower with the nutritional reward of the nectar. However, the new work suggests that using colour as a predictor of temperature can help the bees keep warm.
The study may also have implications for the evolution of specific floral structures and for the connection between floral sensory cues, floral temperature and pollinator behavior.
The original article in Nature
Written by Subhajyoti De