2015年考研模拟试题及答案《通信工程》

　　Being a man hasalways been dangerous. There are about 105 males born for every 100 females,but this ratio drops to near balance at the age of maturity, and among70-year-olds there are twice as many women as men. But the great universal ofmale mortality is being changed. Now, boy babies survive almost as well as girlsdo. This means that, for the first time, there will be an excess of boys inthose crucial years when they are searching for a mate. More important, anotherchance for natural selection has been removed. Fifty years ago, the chance of ababy(particularly a boy baby) surviving depended on its weight. A kilogram toolight or too heavy meant almost certain death. Today it makes almost nodifference. Since much of the variation is due to genes, one more agent ofevolution has gone。

　　There is another way to commit evolutionary suicide: stay alive,but have fewer children. Few people are as fertile as in the past. Except insome religious communities, very few women have 15 children. Nowadays thenumber of births, like the age of death, has become average. Most of us haveroughly the same number of offspring. Again, differences between people and theopportunity for natural selection to take advantage of it have diminished.India shows what is happening. The country offers wealth for a few in the greatcities and poverty for the remaining tribal peoples. The grand mediocrity oftoday―everyone being the same in survival and number of offspring meansthat natural selection has lost 80% of its power in upper-middle-class Indiacompared to the tribes。

　　For us, this means that evolution is over; the biological Utopiahas arrived. Strangely, it has involved little physical change. No otherspecies fills so many places in nature. But in the past 100,000 years—even thepast 100 years—our lives have been transformed but our bodies have not. We did notevolve, because machines and society did it for us. Darwin had a phrase todescribe those ignorant of evolution: “they look at anorganic being as average looks at a ship, as at something wholly beyond hiscomprehension。” No doubt we will remember a 20th century way of life beyondcomprehension for its ugliness. But however amazed our descendants may be athow far from Utopia we were, they will look just like us。

　　1. What used to be the danger in being a man according to thefirst paragraph?

　　[A]A lack of mates。

　　[B]A fierce competition。

　　[C]A lower survival rate。

　　[D]A defective gene。

　　2. What does the example of India illustrate?

　　[A]Wealthy people tend to have fewer children than poor people。

　　[B]Natural selection hardly works among the rich and the poor。

　　[C]The middle class population is 80% smaller than that of thetribes。

　　[D]India is one of the countries with a very high birth rate。

　　3. The author argues that our bodies have stopped evolving because____。

　　[A]life has been improved by technological advance

　　[B]the number of female babies has been declining

　　[C]our species has reached the highest stage of evolution

　　[D]the difference between wealth and poverty is disappearing

　　4. Which of the following would be the best title for the passage?

　　[A]Sex Ration Changes in Human Evolution

　　[B]Ways of Continuing Man's Evolution

　　[C]The Evolutionary Future of Nature

　　[D]Human Evolution Going Nowhere

　　名师解析

　　1. What used to be the danger in being a man according to the firstparagraph?

　　根据第一段，做男人以前有什么危险?

　　[A]A lack of mates. 缺少配偶。

　　[B]A fierce competition. 激烈竞争。

　　[C]A lower survival rate. 低存活率。

　　[D]A defective gene. 有缺陷的基因。

　　【答案】 C

　　【考点】 事实细节题。

　　【分析】 文中第一段提到“做男人从来都充满危险，新生儿男女比例大约是105:100，但到了成年，这一比例基本持平，而在70岁的老人中女性是男性的两倍，但是男性死亡率高这种普遍情况正在改变，现在男婴存活率同女婴的基本一样高”这说明男人的存活率相对是比较低的。

　　2. What does the example of India illustrate?

　　印度的例子证明了什么?

　　[A] Wealthy people tend to have fewer children than poor people。

　　富人往往孩子比穷人少。

　　[B] Natural selection hardly works among the rich and the poor。

　　自然选择在穷人和富人之间几乎不起作用。

　　[C] The middle class population is 80% smaller than that of thetribes。

　　中产阶级的人口比部落人口少80%。

　　[D] India is one of the countries with a very high birth rate。

　　印度是出生率很高的国家之一。

　　【答案】 B

　　【考点】 推断题。

　　【分析】 使用事例来证明是常见的逻辑思维模式。既然有事例，我们就需要看到它的论点是什么。本文中提到，“进化意义上的自杀还有一种方法：存活，但少生孩子”。首先“现在几乎没有人像过去那样多育。除了在一些宗教社区，几乎没有几名妇女会生15个孩子”表明了“当今出生的数量同死亡年龄一样变得平均化，我们大多数人的子女数量大致相当”，再一次，人与人之间的差异和利用差异进行自然选择的机会降低了。其次，“印度证明了这种情况。这个国家给大城市里的少数人提供财富，而给其余的各部落居民造成了贫困。今天这种每个人的生存机会和子女数量都相同的极其显著的平均化意味着与部落相比，自然选择在印度社会中、上层人群中，已经失去了80%的效力”是为了证明“人与人之间的差异和利用差异进行自然选择的机会降低了”，换言之，“自然选择在穷人和富人之间几乎不起作用”。答案应该是[B]选项。

　　3. The author argues that our bodies have stopped evolvingbecause____。

　　作者认为我们的身体已经停止进化，因为____。

　　[A] life has been improved by technological advance

　　技术进步改善了人的生活

　　[B] the number of female babies has been declining

　　女婴的数量一直在减少

　　[C] our species has reached the highest stage of evolution

　　我们人种已经到达进化阶段

　　[D] the difference between wealth and poverty is disappearing

　　贫富差距间的区别正在消失

　　【答案】 A

　　【考点】 逻辑关系题。

　　【分析】 文中提到停止进化是在第三段第一句“对我们来说，这意味着进化已经结束”。第三段中指出，“在过去的10万年——甚至过去的100年中，我们的生活发生了变化，但我们的身体却没变。我们没有进化。因为机器和社会替我们办了这一切”，“机器”代表的就是“技术”，因此我们可以判定[A]是正确答案。

　　4. Which of the following would be the best title for the passage?

　　以下哪一个最合适做本文标题?

　　[A]Sex Ration Changes in Human Evolution 人类进化中的性别比例变化

　　[B]Ways of Continuing Man's Evolution 继续人类进化的方式

　　[C]The Evolutionary Future of Nature 自然进化的未来

　　[D]Human Evolution Going Nowhere 人类进化无路可走

　　【答案】 D

　　【考点】 文章主旨题。

　　【分析】 文章中在第一段结尾提到“由于大部分差异是由基因引起的，又一个进化的因素消失了。”第二段中说“再一次，人与人之间的差异和利用差异进行自然选择的机会降低了。”第三段提到“但我们的身体却没变。我们没有进化，因为机器和社会替我们办了这一切。”这些都表明作者认为进化机制已不再起作用，认为自然进化机制已不能再左右人口的出生率。在总结全文的第三段时，作者直截了当地指出，进化已经结束。因此可以认为人类的进化是无路可走的。另外三个选项都不全面或者不对题。

　　难句解析：

　　1. There are about 105 males born for every 100 females, but thisratio drops to near balance at the age of maturity, and among 70-year-oldsthere are twice as many women as men。

　　【结构分析】本句由三个分句构成。第一个分句是“There are about 105 males born for every 100 females”，一个“there be”句型;第二个分句“butthis ratio drops to near balance at the age of maturity”是一个简单句;第三个分句是一个“therebe”结构。

　　2. Again, differences between people and the opportunity for naturalselection to take advantage of it have diminished。

　　【结构分析】本句要注意的是有两个主语，分别是“differences between people”和“the opportunityfor natural selection to take advantage of it”。

　　3. The grand mediocrity of today—everyone being thesame in survival and number of offspring—means that naturalselection has lost 80% of its power in upper-middle-class India compared to thetribes。

　　【结构分析】本句的主干是“The grand mediocrity means that+宾语从句”。其中“compared tothe tribes”是分词结构作状语。破折号中间“everyone being the same in survival and number of offspring”是典型独立主格结构做插入语，其中“survival”和“number of offspring”都是介词“in”的宾语。

　　　全文翻译：

　　做男人从来都充满危险，新生儿男女比例大约是105:100，但到了成年，这一比例基本持平，而在70岁的老人中女性是男性的两倍，但是男性死亡率高这种普遍情况正在改变，现在男婴存活率同女婴的基本一样高。这就意味着男孩到了寻找伴侣的关键年龄将首次出现男孩过剩。更重要的是，又一次自然选择的机会消失了。50年前，婴儿，尤其是男婴，存活的机会取决于体重，过轻一公斤或过重一公斤几乎意味着必死无疑。今日体重几乎没有什么区别。由于大部分差异是由基因引起的，又一个进化的因素消失了。

　　进化意义上的自杀还有一种方法：存活，但少生孩子。现在几乎没有人像过去那样多育。除了在一些宗教社区，几乎没有几名妇女会生15个孩子。当今出生的数量同死亡年龄一样变得平均化，我们大多数人的子女数量大致相当。再一次，人与人之间的差异和利用差异进行自然选择的机会降低了。印度证明了这种情况。这个国家给大城市里的少数人提供财富，而给其余的各部落居民造成了贫困。今天这种每个人的生存机会和子女数量都相同的极其显著的平均化意味着与部落相比，自然选择在印度社会中、上层中已经失去了80%的效力。

　　对我们来说，这意味着进化已经结束;生物学上的乌托邦已经形成。奇怪的是，这一过程几乎丝毫没有造成身体上的改变，而且没有其他物种充斥着自然中如此多的空间。但在过去的10万年——甚至过去的100年中，我们的生活发生了变化，但我们的身体却没变。我们没有进化。因为机器和社会替我们办了这一切。达尔文有一句话描述那些对进化一无所知的人，他们“看有机的生命如同野人看船，好像看某种完全不能理解的东西”。毫无疑问，我们将记住20世纪的生活方式，尽管对其丑陋之处不得其解，但是，不管我们的子孙后代对我们离乌托邦的理想境界还差多远，感到有多么惊讶，他们的样子会同我们差不了多少。