A farmer uses DDT to kill insects in his field. The first year nearly all of the insects were killed. By the fourth year, however, nearly all of the insects survived the DDT treatment. Explain the process of natural selection in this population of insects. Include these words - mutation, phenotype, variation, resistance, adaptation, and differential survival.

Explanation:

Selection is the greatest force that alters gene frequency and brings about variation that is evidence in a population. There are both natural and artificial selection.

Mutation is one of the force that alters population frequency it is an heritable change that is sudden and occur in the gene, it can be induced or caused naturally.

The insect survived the DDT used because over the years they have build immunity and resistance against the chemical, they now mutate and produce gene that becomes resistance to the chemical and now adapted or adaptable to the environment. Natural selection helps in the continuous perpetuation of the new phenotype and a new differential survival rate.