There has been a lot of talk recently about Asian giant hornets (Vespa mandarinia), the size of your thumb, flying through China, destroying colonies of European honey bees (Apis mellifera) and stinging humans to death. The European honey bees, incidentally, have been introduced to Japan for their higher productivity.

Native Japanese honey bees (Apis cerana japonica), have evolved a defense mechanism against Asian giant hornet attacks. How? Hundreds of Japanese honey bees will immediately surround a hornet which enters the bee colony. The Japanese honey bees vibrate their flight muscles, raising the temperature of the hornet to a lethal 46 °C. These honey bees can tolerate up to 50 °C. All the while, the exertions of the honey bees raise the level of carbon dioxide level around the hornet, suffocating it. A video from National Geographic shows how the Japanese honey bees swarm a hornet. 

The European honey bee, also introduced into Saskatchewan, has not evolved any defense against the Asian giant hornet, even though they are a close relative of the Japanese honey bee. In its native range, the European honey bee does not encounter the Asian giant hornet, and they have not evolved together, so the bee has no defense. Strangely, the European honey bees are preyed upon by the European hornet (Vespa Crabro), also introduced into North America. Despite this, European honey bees have not evolved the “hornet cooking technique”. Regardless, hornets are formidable predators of European honey bees.