How can pests develop resistance to pesticides?

Pests can develop resistance to pesticides primarily through repeated exposure to the same pesticide over time. When these organisms are continuously exposed to a pesticide, some individuals may possess genetic traits that make them less susceptible or even immune to the chemical's effects. These resistant pests survive and reproduce, leading to a population that has a higher proportion of individuals with resistance traits.

Over time, as the pesticide is used repeatedly, the less resistant individuals are eliminated, and the resistant ones thrive, causing a noticeable decline in the pesticide's effectiveness. This phenomenon is often referred to as "selection pressure," where the use of a pesticide effectively selects for individuals that can survive despite its application.

This process illustrates the importance of employing integrated pest management strategies, which may include rotating different types of pesticides or using alternative control methods to prevent the buildup of resistance in pest populations.