阅读理解 Ask why most people are right-handed, and the answer might fall along the same lines as why fish school(鱼成群地游). Two neuroscientists suggest that social pressures drive individuals to coordinate their behaviors so that everyone in the group gets an evolutionary edge.
Approximately 85 percent of people prefer their right hand, which is controlled by the left hemisphere of the brain. One theorized benefit of locating a particular function in one hemisphere is that it frees the other to deal with different tasks. But that idea does not explain why population-wide trends for handedness exist in the first place.
Moreover, evidence gleaned in recent years has overturned the long-held belief that human handedness is a unique by-product of brain specialization attributable to language. A suite of studies has revealed brain lateralization in species from fish to primates(灵长类). Last August, for instance, scientists discovered that in the wild, chimpanzees show hand preferences.
The presence of lateralization throughout the animal kingdom suggests some benefit from it, contend neuroscientists Giorgio Vallortigara and Lesley Rogers. Also, last August, in the journal Behavioral and Brain Sciences, the two presented evidence to support their idea that social constraints force individuals toward asymmetry in the same direction. They noted, for example, that baby chickens attack more readily when a threat appears on their left.
单选题 1.Fish school suggests that______.
【正确答案】 B
【答案解析】细节题。文章第一段介绍左右手习惯并非人类所独有,动物也呈现类似的特点,如鱼成群的游动。这是因为社会压力迫使个体调整自己的行为,这也形成了它们的进化优势。鱼成群的游动并非必要的进化过程,而是形成了进化优势,所以不能选择A。选项C和D在原文中没有提到。B项has/have something to do with意为“和…有关”。故选B。
单选题 2.Locating a particular function in one hemisphere______.
【正确答案】 A
【答案解析】推理判断题。根据第二段第三句话“But that idea does not explain why population—widetrends for handedness exist in the first place.”可知,大脑两半球功能分配的理论并不能解释为什么大多数人有左右手习惯。前面提到85%的人习惯使用右手,它由人的大脑左半球控制,这样做是为了让另一个半球来处理不同的任务。所以B和D选项错。故选A。
单选题 3.Due to______, human handedness is not an exclusive phenomenon in animal world.
【正确答案】 A
【答案解析】推理判断题。第三段说人们一直认为左右手习惯是人的特有特征,是人大脑中语言功能区进化的附属品,现在这个论断被推翻了。因为从鱼到灵长类动物(黑猩猩)的脑部都具有侧向性的发育特点。这与A项相符合,故选A。
单选题 4.Why are baby chickens so prepared in fighting against enemies from left?
【正确答案】 B
【答案解析】细节题。第四段说神经学家乔治·维罗提格拉和莱斯利·罗杰斯在科学期刊上发表的论文提到,环境约束使动物个体的行为呈现“侧向性”,而其中一个例子就是小鸡习惯某一侧攻击入侵的敌人。故选B。
单选题 5.Which of the following is the best title for this passage?
【正确答案】 B
【答案解析】主旨判断题。本文探讨的是人类左右手习惯与动物行为侧向性之间的联系。选项A、C、D只是短文某一方面内容,太片面。故选B。