Thirty Japanese giant hornets take on an entire hive of European honey bees and slaughter 30,000 bees in three hours.
Not having evolved alongside the giant hornet, European honey bees don’t have a natural defense against them. But the Japanese honey bee does:
The Japanese honey bee, on the other hand, has a defense against attacks of this manner. When a hornet approaches the hive to release pheromones, the bee workers emerge from their hive in an angry cloud-formation with some 500 individuals. As they form a tight ball around the hornet, the ball increases in heat to 47 °C (117 °F) from their vibrating wings, forming a convection oven as the heat released by the bees’ bodies is spread over the hornets. Because bees can survive higher temperatures (48 to 50 °C (118 to 122 °F)) than the hornet (44 to 46 °C (111 to 115 °F)), the latter dies.