Infrared video shows bees "cooking" wasp invader

 It's an unlikely way to deal with an intruder but some honeybees cook wasps that invade their colony. The tactic is usually invisible to the naked eye but now a new infrared video captured by Barrett Klein and colleagues from the University of Wuerzburg in Germany exposes the thermal assault involved.

The video, filmed through an observation window let into the wall of a hive, follows the bees as they mob the wasp. Then a close-up shows them generating heat by contracting their wing muscles to suffocate the intruder.