Final answer:
The concept of 'survival of the fittest' refers to traits that allow organisms to survive and pass on their genetics, leading to populations that can become resistant to insecticides over time. Insects with mutations for resistance will reproduce, eventually creating a majority of resistant insects.
Step-by-step explanation:
Survival of the Fittest and Insecticide Resistance
Charles Darwin's concept of natural selection, sometimes summarized as survival of the fittest, has significant implications for the relationship between insects and insecticides.
In an insect population, if some individuals happen to have a genetic mutation that confers resistance to a particular insecticide, these insects are more likely to survive and reproduce when that insecticide is used. Over time, these resistant genes become more common in the population, leading to pesticide resistance.
For example, if insects of the same species compete for a limited food source, and one group has a better sense of smell, those with the better sense of smell are more likely to find food and survive to reproduce. Their offspring will likely inherit this advantageous trait, leading to a population that overall has a better sense of smell.
Similarly, in the case of insects versus insecticides, those insects that have mutations allowing them to survive the insecticide will become the dominant strain over time, as those without such resistance die off.