State whether you think this effect is positive, negative, or both positive and negative. Explain why you think so.

The draining of swampy areas and the use of insecticides have greatly reduced populations of disease-carrying mosquitoes in many areas. State whether you think this is a positive or negative effect of our species on the biosphere, and your reasons why. Name at least one example of an effect of humans on the biosphere. State whether you think this effect is positive, negative, or both positive and negative. Explain why you think so.