London, June 29 (ANI): Despite constant daylight of the Arctic summer, bumblebees stick to a working routine and return to their nests well before midnight - suggesting that they can tell the time in the absence of day/night cues, according to a new study.
Ralph Stelzer and Lars Chittka from Queen Mary University of London, UK, observed "Constant daylight would seem to provide a unique opportunity for bumblebee foragers to maximise intake, and therefore colony growth, by remaining active during the entire 24-hour period. We found that bees do not naturally take advantage of this opportunity, suggesting that there is some benefit to an 'overnight' break".
The researchers believe that that the insects may be sensitive to light intensity and quality or changes in temperature - allowing them to 'tell the time'.
"Despite the light, temperatures do fall during the Arctic 'night', so it may be that the bees need to return to their nests in order to warm their brood. Also, it has been suggested that a period of sleep helps bees to remember information gained during the day's foraging," said the researchers.
The study has been published in the open access journal BMC Biology. (ANI)