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先上文： Researchers studying how genes control animal behavior have had to deal with many uncertainties. In the first place, most behaviors are governed by more than one gene, and until recently geneticists had no method for identifying the multiple genes involved. In addition, even when a single gene is found to control a behavior, researchers in different fields do not necessarily agree that it is a “behavioral gene.” Neuroscientists, whose interest in genetic research is to understand the nervous system (which generates behavior), define the term broadly. But ethologists ― specialists in animal behavior― are interested in evolution, so they define the term narrowly. They insist that mutations in a behavioral gene must alter a specific normal behavior and not merely make the organism ill, so that the genetically induced behavioral change will provide variation that natural selection can act upon, possibly leading to the evolution of a new species. For example, in the fruit fly, researchers have identified the gene Shaker, mutations in which cause flies to shake violently under anesthesia. Since shaking is not healthy, ethologists do not consider Shaker a behavioral gene. In contrast, ethologists do consider the gene period (per), which controls the fruit fly’s circadian (24 hour) rhythm, a behavioral gene because files with mutated per genes are healthy, they simply have different rhythms. 1.The passage suggests that neuroscientists would most likely consider Shaker to be which of the following? A. An example of a behavioral gene B. One of multiple genes that control a single behavior C. A gene that, when mutated, causes an alteration in a specific normal behavior without making the organism ill D. A gene of interest to ethologists but of no interest to neuroscientists E. A poor source of information about the nervous system OA: A 2.It can be inferred from the passage that which of the following, if true, would be most likely to influence ethologists' opinions about whether a particular gene in a species is a behavioral gene? A. The gene is found only in that species. B. The gene is extremely difficult to identify. C. The only effect of mutations in the gene is to make the organism ill. D. Neuroscientists consider the gene to be a behavioral gene. E. Geneticists consider the gene to be a behavioral gene. OA: C 3.The primary purpose of the passage is to A. summarize findings in an area of research B. discuss different perspectives on a scientific question C. outline the major questions in a scientific discipline D. illustrate the usefulness of investigating a research topic E. reconcile differences between two definitions of a term OA: B
私以为这篇文章非常的不条理，而且存在前后矛盾的嫌疑（欢迎拍砖）。 1.They insist that mutations in a behavioral gene must alter a specific normal behavior and not merely make the organism ill, so that the genetically induced behavioral change will provide variation that natural selection can act upon, possibly leading to the evolution of a new species. 这里的they 很明显指的是前文的ethologists，说了ethologists认为行为基因的变异必须满足两个条件：1.改变特定行为。2.不仅仅是引起生物生病（也就是引起生病以外其他的症状）。 后文的例子中又说researchers have identified the gene Shaker, mutations in which cause flies to shake violently under anesthesia. Since shaking is not healthy, ethologists do not consider Shaker a behavioral gene. 这里难道不应该是“shaking是不健康的”满足了behavioral gene的条件2吗？怎么就直接得出结论Shaker不是行为基因？后面的gene period，因为它是健康的，就被ethologists认为是a behavioral gene了。 想问问大神们是我个人理解错误吗？ Thanks in advance.
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发表于 2019-1-27 19:10:23
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