It's a hot mess.
feasting on honeybee larvae has nothing to fear from a honeybee's stinger. That puny thing? Ain't gonna pierce this rigid exoskeleton. But 500 angry bees---now that's a problem. When Japanese honeybees detect a hornet in their hive, they swarm around it by the hundreds. The collective vibration of their flight muscles makes it just hot enough (about 116 F) to be lethal for the hornet. Give it 30 to 6o minutes, and the hornet has been cooked to death. Japanese scientists were curious about the brain activity that coordinated this complex honeybee behavior. After baiting the honeybees with a doomed hornet (see video below), they plucked several bees from the ball and identified brain areas active during the hot defensive bee ball
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Image via Ugajin et al, PLoS ONE; video via PopSci