Believe it or not, these mosquitoes are the good guys! Scientists in Florida hope they'll help reduce the population of disease carrying mosquitoes. The lab-bred sterile males have been infected with bacteria that, while not harmful to humans, will keep their baby mosquitoes from growing to maturity. "We're releasing many thousands of sterile males," William Petrie, Miami-Dade Mosquito Control Director, said. When those males mate with wild females, he said, "none of the progeny survive."