Answer: Heat

Japanese honey bees, a subspecies of the eastern honey bee found on mainland Asia, is the primary honey bee species in Japan for one reason. Despite the efforts of Japanese farmers to introduce European honey bees for the sake of their high productivity, the European bees couldn’t defend their colonies against aggressive Japanese giant hornets. The hornets are such fearsome predators to the bees that even a few hornets can completely wipe out an entire colony.

The Japanese honey bees, however, have an excellent and coordinated defense plan that succeeds where the stinging assault of the European honey bees fails. Rather than attempt to take down the hornets with their stingers (an ineffective technique that does little to faze the hornet), the Japanese bees instead mob the hornet, creating a large ball around it.

Once balled around the hornet, they begin to vibrate their bodies in exactly the same way they would to raise the temperature of their hive, but are instead transferring their heat to the hornet’s body and raising the level of carbon dioxide in the ball. The higher level of carbon dioxide combined with the bees ability to withstand temperatures approximately 7 degrees Fahrenheit (4 degrees Celsius) hotter than the hornet can kills the hornet before it can cause irreparable damage to the colony.