Question

A farmer observes that increasingly higher concentrations of a particular pesticide have been required each year over the past ten years to achieve the same level of effectiveness on a specific insect pest. Which of the following best helps explain the observation?
A) Some individual insects live longer that others and pass on traits acquired during their lives.B) Only the most aggressive and territorial insects survive and reproduce.C) Some individual insects are more likely than others to survive and reproduce due to their inherited traits.D) Some individual insects reproduce before the pesticide is applied, thereby avoiding its harmful effects.

Answer 1

Answer:

C) Some individual insects are more likely than others to survive and reproduce due to their inherited traits.

Explanation:

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, for example:

• many insects species produce large broods. This increases the probability of mutations and ensures the rapid expansion of resistant populations.
• Insects with shorter life times develop resistance more quickly than others because its genetics make them reproduce much faster.
• insects with limited diets are more likely to evolve resistance, because they are exposed to higher pesticide concentrations and has less opportunity to breed with unexposed populations.

But this kind of phenomenon has not only observed in insects in England, rats in certain areas have evolved resistance that allows them to consume up to five times as much rat poison as normal rats without dying.