An insect pest known as the medfly significantly reduced the orange crop on California. Pesticides were used to control the medfly. Using the concept of natural selection, explain how the continued use of a certain pesticide may become ineffective in controlling this fly. Your answer must include the concepts of
•Variation
•Adaptation
•Survival
•Reproduction

The overuse of any pesticide will make the pest develop immunity to it, by adapting to it.

Explanation:

Any insect pest that infects a cop is controlled by pesticides. These insect species show variation in the DNA of different forms that attack different crops but in general one crop has the same pest and is affected on by the pesticide much the same.

The overuse of the same pesticide however is detrimental for the humans. The pests eventually are able to adapt to the pesticide and develop an immunity against it for the survival of their species.

Then during reproduction they pass on this immunity to the offspring, making that particular pesticide useless.

increase soil erosion                                             reduce soil erosion

cattle grazing                                                         hydroseeding

deforestation                                                         contour plowing

                                                                                planting vegetation

plant roots basically hold the top soil

together and stop soil erosion because

in such situation top soil is not removed

during flood but cattle grazing causes

soil erosion because cattle consume the

grasses and herbs and top soil is exposed.

same situation occurs because of

deforestation, the trees and plants are cut

down to expose top soil which causes soil

erosion