Refocus this paragraph assignment
1) Reorganize the 9 sentences below into a coherent paragraph. Hint: Find the main idea, then each successive sentence should add more details to the sentence before it.
2) Explain the organizing patterns, both overall and from one sentence to the next sentence. The key to successfully solve this puzzle is to look for the clues within each sentence that will tell you which sentence comes next. Post your solution in this assignment box. And please do not cheat by looking the paragraph up online—you might find the paragraph but you will not find the answers to #2 online! 🙂
Cotton became the principal crop in the Cafiete Valley of Peru (south of Lima), replacing sugarcane and other crops, when irrigation was expanded in the 1930s and 1940s. After World War II entomologists advised growers to use cultural control measures to protect the cotton by, for example, destroying weeds that harbored the insect pests that attacked cotton plants. One of the least appreciated ecosystem services that biodiversity supplies to us is the control of agricultural pests by natural enemies. But the lure of new synthetic pesticides was too much for the growers. DDT and several of its “chlorinated hydrocarbon” chemical relatives were widely used in the valley starting in 1949. The Cafiete Valley was blanketed with them, and many trees were chopped down to make it safer for crop-dusting aircraft to spray the fields. At first it seemed the growers had chosen wisely: cotton yields that had been at 495 kilograms per hectare in 1950 rose to 729 kilograms per hectare in 1954. As yields climbed, growers concluded that the more pesticides they used, the better off they would be. This was brought home to biologists some time ago by what is known as the Cafiete Valley cotton disaster.
