单选题 It's obvious that humans are fundamentally different from other animal species. It's not so easy, though, to identify the traits that make human beings so special. Scientists realized long ago that other animals make tools, play jokes and even have a sense of justice and altruism—all things we once thought were unique to our species.
Now a paper in the journal Current Biology has added another behavior to the list of what other animals share with us—and this one isn't quite so charming. After years of field observations in Uganda's Kibale National Park, John Mitani of the University of Michigan and several colleagues have concluded that chimps wage war to conquer new territory.
"We already knew that chimps kill each other," says Mitani. "We've known this for a long time." What scientists didn't know for certain, at least in cases in which groups of chimps banded together to kill others, was why. One hypothesis, advanced more than a decade ago by anthropologist Richard Wrangham, was the idea of territorial conquest; circumstantial evidence from both Gombe and Mahale national parks in Tanzania bolstered the theory.
In Mahale, for example, male members of one group mysteriously vanished, and another group then expanded into what had been their land. In Gombe, an existing group dissolved into civil war, resulting in killings and land takeovers.
What's especially chilling about the observation is that the murder rate appears to be so high. The anthropologists couldn't be certain of how big a band the victims belonged to because they weren't used to a human presence and thus couldn't be accurately counted. But even a conservative estimate suggests that the death rate is significantly higher than you would see in war between human hunter-gatherer groups.
Mitani isn't oblivious to the lesson some people might draw from the study. "Invariably, some will take this as evidence that the roots of aggression run very deep," he says, and therefore conclude that war is our evolutionary destiny. "Even if that were true," says Mitani, "we operate by a moral code that chimps don't have."
Apart from that, he points out, the Pan troglodytes chimps he studies are one of two subspecies. The other is called Pan paniscus, also known as bonobos, and, says Mitani, "the latter, as far as we know, aren't nearly as aggressive with respect to intergroup relations. Yet they're equally close to us." That means that if we're wired for warfare, we're wired for peace too. Ultimately, the route we choose is still up to us.

单选题 John Mitani concludes that chimps______.

【正确答案】 B

【答案解析】[试题类型] 具体信息题。
[解题思路] 根据题干关键词John Mitani concludes定位到文章第二段未句。该句指出，三谷(Mitani)和他的几位同事得出结论：为了占领新领地，黑猩猩也会开战(chimps wage war to conquer new territory)，由此可见，选项[B]“黑猩猩在某些时候会对其他成员具有攻击性”与原文意思相符，故为答案。
[干扰排除] 原文中三谷得出的结论是黑猩猩在某些情况下会开战，而不是在某些情况下难以接近(hard to approach)，故排除选项[A]。由文中第二段可知，三谷及其同事经过若干年野外观察，发现了黑猩猩与人类近似的一种行为，即会为了占领新领地而发动战争，这只是三谷发现的黑猩猩同人类共有的一个习性，至于黑猩猩与人类是否有很多相似的特性(many similar traits)，从三谷的研究中无法推知，故排除选项[C]。文章第二段未句提到，三谷提出结论：黑猩猩开战的原因是为了占领新领地，故选项[D]“黑猩猩杀害彼此的原因不详”不符合题干。

单选题 The word "bolstered" (Line 5, Paragraph 3) has the closest meaning to______.

【正确答案】 D

【答案解析】[试题类型] 语义理解题。
[解题思路] bolster一词出现在第三段最后一句。该句指出，人类学家理查德·厄姆提出了一种假设：黑猩猩开战是为了占领领地(the idea of territorial conquest)。紧接着分号后指出，在冈贝国家公园和马哈尔国家公园发现了能够bolster这一理论的间接证据(circumstantial evidence)。“发现提供的证据”对理论要么是“支持；论证”，要么是“推翻；驳倒”，而第四段具体说明了这种观察发现：黑猩猩确实为了夺领地而战斗，故bolstered应表达“支持；证明”的意义，四个选项中，只有选项[D]confirmed(证明；证实)意思与此最接近，故选项[D]正确。
[干扰排除] 由以上分析可知，[A]“持有”，选项[B]“质疑”，[C]“创立；提出”皆不符合文意。

单选题 What problem did the anthropologists meet in studying the chimps?

【正确答案】 C

【答案解析】[试题类型] 推理引申题。
[解题思路] 题干对人类学家(anthropologists)在研究黑猩猩时所遇到的问题提问，由此定位到文章第五段。该段第二句指出，人类学家不能确定遇难的黑猩猩所属的群体有多大(the anthropologists couldn't be certain of how big a band the victims belonged to)，即人类学家不能确定有多少黑猩猩参与战争，故选项[C]“他们不能确定参战的黑猩猩的数目”最符合文意。
[干扰排除] 文章第三段提到“科学家不能确定为什么黑猩猩会互相残杀”，但后文接着指出，人类学家理查德·兰厄姆为其原因提出了一种假设，并且该假设被大量证据间接地证实了，故不能说科学家对黑猩猩互相残杀的原因一无所知，排除选项[A]。第三段未句指出，在坦桑尼亚冈贝国家公园和马哈尔尔国家公园发现大量的证据间接地证实了这一假说(circumstantial evidence...bolstered the theory)，此处的theory即兰厄姆的假设(Wrangham's hypothesis)，故选项[B]错误。原文并没有提到没有足够的人手参与到野外观察中，排除选项[D]。

单选题 Which of the following statements is true according to the passage?

【正确答案】 A

【答案解析】[试题类型] 推理引申题。
[解题思路] 第六段中Mitani指出，有些人会从对黑猩猩的研究中得出结论：侵略的本性根深蒂固(the roots of aggression run very deep)，战争是进化的必然结果(war is our evolutionary destiny)，但他接着指出，人类依照道德行为准则行事，而黑猩猩没有这种准则(we operate by a moral code that chimps don't have)，故选项[A]“在战争问题上，人类受到道德标准的约束”正确。
[干扰排除] 对于黑猩猩互相残杀的原因，文中仅提及了一种假设，即为了占领领地，并朱提及基因因素(genetic factors)，故排除选项[B]。选项[C]是对文章末段最后两句的曲解，此处提到，我们与战争及和平都是紧密相连的，而我们选择何种路线仍由我们自己决定(the route we choose is still up to us)，但并不能过度推出人类对选择和平还是战争感到忧虑，故排除选项[C]。文章最后一段仅比较了两种黑猩猩的好战程度，并指出，倭黑猩猩在处理群间关系时远没有普通黑猩猩那样具有攻击性(the latter...aren't nearly as aggressive...)，由此可见，文中作者将两种黑猩猩的脾气进行了比较，并没有将人类与某些黑猩猩进行比较，选项[D]“有些黑猩猩在性情上比人类要温和得多”未提及，故排除。

单选题 Which of the following would be the best title for the text?

【正确答案】 A

【答案解析】[试题类型] 主旨要义题。
[解题思路] 纵观全文，文章第一段首先指出人类与其他动物物种有着根本的不同，接着笔锋一转，第二段就提出了人类与黑猩猩共有的一种行为：为了争夺领地而战。第三段到第七段说明了科学家们得出这一结论的过程：首先提出假设，然后用实例证明假设，最后得出结论。由此可见，整篇文章都是围绕黑猩猩开战展开的，这也是文章的主题，选项[A]的含义与此相符。
[干扰排除] 文章第五段提到了黑猩猩互相残杀时的高谋杀率(murder rate appears to be so high)，但这只是科学家在研究黑猩猩之间战争时的发现之一，不足以概括文章大意，故排除选项[B]。文章在最后一段提到了黑猩猩的两个亚种(two subspecies)，普通黑猩猩和倭黑猩猩，并对其好战性进行了比较，但这属于文章细节，不是主要讨论的内容，故排除选项[C]。选项[D]的含义为“人类特有的特征”，全文论述的中心为黑猩猩，而非人类，故排除该选项。