In 1957 , a beekeeper in Brazil was trying to breed stronger bees. He wanted bees that would produce more honey. He mated two species of bees. One of the bee types was the Tanzanian African bee. This was a mistake. When the two bee species mated, they created a third very aggressive bee species. Regrettably, 26 of these new aggressive African queen bees escaped from their bee hives. They have since interbred with more common and non-aggressive European bees all around the world