Because of fatal infestations of two parasites, almost all honey bees in North America now are raised by beekeepers. Already many beekeepers in Mexico have stopped keeping bee hives because of the eager stingers, he noted. Africanized honey bees are a genetic variant of our own European-origin honey bees. The interlopers are considerably more aggressive. Research conducted in Venezuela found that Africanized honey bees will attack a visual stimulus 20 times faster than European honey bees and that when they attack they deposit about eight times as many stingers in the first 30 seconds.
Different insects use various methods to protect themselves from predators.
Davis and Ernesto Guzman-Novoa of Mexico's agricultural research service identified the mean gene by measuring the speed and intensity of stinging behavior in 162 colonies of hybrid bees. They then located gene markers on the chromosomes of the aggressive hybrid bees and compared the genes with those of non-aggressive hybrid bees. This process hasn't been used much in insects. But if you have markers for the genes, we can do what the crop geneticists are doing and selectively breed for gentle bees. The scientists identified five genes that appear to have some link to the aggressive behavior, and one of these genes was found to have a much greater effect on the tendency to sting.