Honeybees can precisely regulate the temperature of their nest – and they do it thanks to genetically determined variations in their individual thermostats. The new research has revealed one of the few known benefits of the high genetic diversity found in honeybee colonies.Maintaining a nest temperature of between about 32°C and 36°C is vital during spring and summer, when eggs are developing and hatching. “If they don’t keep the nest at this temperature, the brood won’t develop properly,” says Julia Jones of the University of Sydney, Australia, who led the work.If the temperature drops too low, the worker bees huddle together around the brood to keep it warm. If it gets too high, they stand at the nest entrance and use their wings to fan out hot air. The new work shows that bees with different fathers start fanning at slightly different temperatures. This stops sudden colony-wide shifts between warming and cooling behaviours, and keeps the temperature in the nest more constant.“It’s been shown before that honeybees with different genotypes have different thresholds for certain things – for instance, they’re attracted to different concentrations of nectar,” says Jones. “But this is the first time any benefit has been shown from different behaviour thresholds based on genotype in the bees.”