Bees physically transfer heat to stay cool

New York, July 26 (IANS) To protect their young ones from heat, honey bees can absorb heat from the brood walls just like a sponge and later transfer it to a cooler place to get rid of the heat from their bodies, says a study.

"Moving heat from hot to cool areas is reminiscent of the bio-heat transfer via the cardiovascular system of mammals," said Philip Starks, a biologist at Tufts University in the US.

This is the first study to show that worker bees dissipate excess heat within a hive in process similar to how humans and other mammals cool themselves through their blood vessels and skin.

"This study shows how workers effectively dissipate the heat absorbed via heat-shielding, a mechanism used to thwart localised heat stressors," Starks added.

Previous research has shown that workers bees, among other duties, control the thermostat essential to the hive's survival.

When temperatures dip, worker bees create heat by contracting their thoracic muscles, similar to shivering in mammals.

To protect the vulnerable brood when it is hot, workers fan the comb, spread fluid to induce evaporative cooling, or - when the heat stress is localised - absorb heat by pressing themselves against the brood nest wall (a behaviour known as heat-shielding).

But until this study, scientists did not know how the bees got rid of the heat after they had absorbed it.

For the study, researchers collected data on seven active honey bee hives that were framed by clear Plexiglas walls and using a theatre light, the researchers raised the internal temperature of the hives for 15 minutes.

Using thermal imaging, the scientists observed that bees had physically moved the absorbed heat in their bodies to previously cooler areas of the hive.

The study appeared in the journal Naturwissenschaften, The Science of Nature.