The term "Killer Bee" refers to the Africanized honey bee, a hybrid of the African honey bee and European honey bee. These bees are known for their aggressive behavior and tendency to swarm, which can pose a danger to humans and animals. They were first introduced to the Americas in the 1950s and have since spread throughout parts of the United States and South America. Killer Bees are smaller than their European counterparts but are more defensive of their hives. They can chase perceived threats for long distances, making them particularly dangerous. Despite their aggressive nature, they still play a crucial role in pollination and maintaining ecosystems.