Insects are known for their ability to develop resistance to insecticides. Currently there are insects resistant to every synthetic chemical insecticide used. There are many factors to developing resistance. In a population of insects there may be a few individuals that carry the genes for resistance. These genes arise from mutations and are rare. In the natural environment the mutant insect is typically compromised, weaker and produces less progenies. Upon exposure to insecticides, insects that do not carry the resistance genes die, thus allowing the individuals with the resistance genes to survive and reproduce, creating more resistant insects. With every generation the number of resistant insects increase.