Mosquitoes can carry and transmit many diseases to humans. In the past, the insecticide DDT was heavily used to reduce mosquito populations in order to reduce instances of disease transmission. However, after some time, mosquito populations developed a resistance to DDT, which made the DDT less effective in reducing mosquito populations.

Question

Based on what you’ve learned about natural selection, in 3–5 sentences, describe how mosquitoes may have come to develop this resistance.

Answer 1

Mosquitoes may have come to develop resistance to DDT through natural selection. Individuals with genetic variations that made them less susceptible to the insecticide were more likely to survive and reproduce, passing on those advantageous traits to their offspring. Over time, this led to an increase in the frequency of the resistant alleles in the mosquito population, making it more difficult to control their populations with DDT. Other factors, such as overuse and misuse of the insecticide, may have also played a role in the evolution of DDT resistance.