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自考英语笔译教材
About a quarter of a century ago Dr. Knipling startled his colleagues by proposing a unique method of insect control. ;If it were possible to sterilize and release large numbers of insects, he theorized, the sterilized males would, under certain conditions, compete with the normal wild males so successfully that, after repeated releases, only infertile eggs would be produced and the population would die out. ;The proposal was met with bureaucratic inertia and with skepticism from scientists, but the idea persisted in Dr. Knipling’s mind. One major problem remained to be solved before it could be put to the test --- a practical method of insect sterilization had to be found. ;Academically, the fact that insects could be sterilized by exposure to X-ray had been known since 1916, when an entomologist by the name of G. A. Runner reported such sterilization of cigarette beetles. ;Hermann Muller’s pioneering work on the production of mutations by X-ray opened up vast new areas of thought in the late 1920’s, and by the middle of the century various workers had reported the sterilization by X-rays or gamma rays of at least a dozen species of insects. ;But these were laboratory experiments, still a long way from practical application. About 1950, Dr. Knipling launched a serious effort to turn insect sterilization into a weapon that would wipe out a major insect enemy of livestock in the South, the screw-worm fly. ;The females of this species lay their eggs in any open wound of a warm-blooded animal. The hatching larvae are parasitic, feeding on the flesh of the host. ;原文: The hatching larvae are parasitic, feeding on the flesh of the host;A full-grown steer may succumb to a heavy infestation in 10 days, and livestock losses in the United States have been estimated at $40,000,000 a year. ;The toll of wildlife is harder to measure, but it must be great. Scarcity of deer in some areas of Texas is attributed to the screw-worm.;This is a tropical or subtropical insect, inhabiting
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