video transcript

The Japanese honeybee looks much like any other species, but when it comes to dealing with invaders like the giant Asian hornet, it is fundamentally different. Even when not held by a wire, the hornet rarely comes out alive. Up to 500 bees swarm around it in what scientists call a 'hot defensive bee ball'. By vibrating their flight muscles the bees raise the temperature inside the ball to a point where the hornet is essentially, cooked to death. University of Tokyo graduate student Atsushi Ugajin says the bees' stingers aren't strong enough to penetrate the tough exo-skeleton of the hornet, so the ball does the job for them. SOUNDBITE) (Japanese) TOKYO UNIVERSITY GRADUATE STUDENT, ATSUSHI UGAJIN SAYING: "The high temperature phase of 46 degrees celcius lasts about 20 minutes during which time the hornet is killed." For Professor, Takeo Kubo, the most remarkable aspect of the bees' behaviour is in the teamwork. (SOUNDBITE) (Japanese) UNIVERSITY OF TOKYO PROFESSOR, TAKEO KUBO SAYING: "When an outsider enters, the honeybees are immediately on their guard, then, all at once they gather to attack. So, it isn't one commanding the rest, we believe in this moment of emergency that they're acting collectively to create the 'defensive bee ball'." When they examined the brains of the bee, the scientists found that neural activity was trigged during the formation of the bee ball, indicating a direct response to temperature change. The scientists believe that thermal stimulation might allow the bees to protect themselves while they're killing their enemy. SOUNDBITE)(Japanese) UNIVERSITY OF TOKYO PROFESSOR, TAKEO KUBO SAYING: "One of the great mysteries for us is how animals' brain have evolved and how they operate. This will be for us the next great puzzle to examine." Honeybee expert Masato Ono agrees. Evolution he says has created some extraordinary examples of animal behaviour. The Japanese honeybee he says, has merely adapted to a natural threat. The hornet may have to adapt accordingty to survive. Rob Muir, Reuters.