Chapter 16, Problem 1TC

Summary Introduction

To determine:

The observations on the field on the basis of natural selection. Also, to determine whether government should regulate pesticide application to prevent insects from evolving resistance or not.

Introduction:

A farmer applies a new pesticide to his field. He applied the pesticide as it was directed by the manufacturer, but the farmer lost 15% of his crops to insects. A second farmer applied three times pesticide by learning the results of the former. He lost only 3% of his crops. Both these farmers continued to apply the pesticide the same way for the next 5 years. At the end, the first farmer was still losing 15% of his crops, but the second farmer lost 40% of his crops.

Explanation of Solution

The term “natural selection” was given and popularized by Charles Darwin. Simply, it is defined as “survival of the fittest”. It is the differential survival of organisms on the basis of their phenotype and genotype. Natural selection is the key to evolution.

The second farmer was applying three times more pesticide as directed by the manufacturer. This caused the insects to become resistant to it. When he applied the pesticide for the first time, many of the insects died because these were not resistant to it. As time passed, some insects developed mutation and became resistant. Natural selection allowed their growth and reproduction. At the end, all the insects became resistant to that particular pesticide and damaged 40% of the farmer’s crop.

Government should regulate the application of pesticides in order to prevent insects from evolving resistance as it would lead to the development of superpests that cannot be controlled with any pesticide or insecticide. Government should put certain restrictions on the usage of pesticides. There should be a limit for this. Otherwise, strict actions should be taken against the farmer or some penalty should be fixed for this purposes.

Conclusion

Too much use of pesticide or any other chemical can induce mutation and natural selection will make a whole new population of insects that are resistant and can also lead to the creation of superpests.