首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
考研
[A]The role of natural selection in this colorful world [B]The delicate hierarchy of the natural system [C]The agency of
[A]The role of natural selection in this colorful world [B]The delicate hierarchy of the natural system [C]The agency of
admin
2016-11-11
48
问题
[A]The role of natural selection in this colorful world
[B]The delicate hierarchy of the natural system
[C]The agency of selection can account for more cases
[D]The impotence of creationism
[E]Natural selection acts by competition
[F]No leaps in natural evolution
As each species tends by its geometrical rate of reproduction to increase excessively in number: and as the modified descendants of each species will be enabled to increase by as much as they become more diversified in habits and structure, so as to be able to seize on many and widely different places in natural selection to preserve the most divergent offspring of any one species. Hence, during a long-continued course of modification, the slight differences characteristic of varieties of the same species, tend to be augmented into the greater differences characteristic of the species of the same genus.
【C1】______
New and improved varieties will inevitably displace and destroy the older, less improved, and intermediate varieties: and thus species are rendered to a large extent defined and distinct objects. Dominant species belonging to the larger groups within each class tend to give birth to new and dominant forms: so that each large group tends to become still larger, and at the same time more divergent in character. But as all groups cannot thus go on increasing in size, for the world would not hold them, the more dominant groups beat the less dominant.
【C2】______
This tendency in the large groups to go on increasing in size and diverging in character, together with the inevitability of much extinction, explains the arrangement of all the forms of life in groups subordinate to groups, all within a few great classes, which has prevailed throughout all time. This grand fact of the grouping of all organic beings under what is called the Natural System, is utterly unexplainable on the theory of creation.
【C3】______
As natural selection acts solely by accumulating slight, successive, favorable variations, it can produce no great or sudden modifications: it can act only by short and slow steps. We can see why throughout nature the same general end is gained by an almost infinite diversity of means, for every peculiarity when once acquired in long inherited, and structures already modified in many different ways have to be adapted for the same general purpose. We can, in short, see why nature is extravagant in variety, though not generous in innovation. But why this should be a law of nature if each species has been independently created no man can explain.
【C4】______
Many other facts are, as it seems to me, explicable on this theory. How strange it is that a bird, under the form of a woodpecker, should prey on insects on the ground and that upland geese which rarely or never swim, should possess webbed feet, and so in endless other cases. But on the view of each species constantly trying to increase in number, with natural selection always ready to adapt the slowly varying descendants of each to any unoccupied or ill-occupied place in nature, these facts cease to be strange, or might even have been anticipated.
【C5】______
We can to a certain extent understand how it is that there is so much beauty throughout nature: for this may be largely attributed to the agency of selection. That beauty, according to our sense of it, is not universal, must be admitted by every one who will look at some hideous bats with a distorted resemblance to the human face. Sexual selection has given the most brilliant colors, elegant patterns, and other ornaments to the males. With birds it has often rendered the voice of the male musical to the female, as well as to our ears. Flowers and fruit have been rendered conspicuous by brilliant colors in contrast with the green foliage, in order that the flowers may be readily seen, visited and fertilized by insects.
As natural selection acts by competition, it adapts and improves the inhabitants of each country only in relation to their co-inhabitants: so that we need feel no surprise at the species of any one country being beaten and supplanted by the naturalized productions from another land. The wonder indeed is, on the theory of natural selection, that more cases of the want of absolute perfection have not been detected.
【C4】
选项
答案
C
解析
第五段指出:有些物种都在尝试增加数目,作者举了类似啄木鸟形态的鸟、高地的鹅等例子来说明白然选择是在使每一物种的缓慢变异着的后代适应于自然界中未被占据或占据不好的地方,C项“选择的力量可以解释许多个例”更好地总结了这一段。
转载请注明原文地址:https://kaotiyun.com/show/iWoZ777K
0
考研英语一
相关试题推荐
Prewritingreferstostrategiesyoucanusetogenerateideasbeforestartingthefirstdraftofapaper.Prewritingtechniques
WhathappenedattheUnitedNations?Howdidthecriticslikethenewplay?Soonafteranevent【C1】______,newspapersar
Researchhasshownthat—inbothsexesandacrossnumerouscultures—attractivepeoplearejudgedtobesmarter,kinder,morehone
Marriageis,formanypeople,theirmostimportantrelationship,thesourceofmuchhappiness,and,forsome,evenaddsextraye
Marriageis,formanypeople,theirmostimportantrelationship,thesourceofmuchhappiness,and,forsome,evenaddsextraye
Marriageis,formanypeople,theirmostimportantrelationship,thesourceofmuchhappiness,and,forsome,evenaddsextraye
Comparisonsweredrawnbetweenthedevelopmentoftelevisioninthe20thcenturyandthediffusionofprintinginthe15thand1
TheFederalTradeCommissionhadsomesharpwordsforInternetcompaniesThursday,sayingthattheyarenotexplainingtotheir
TheFederalTradeCommissionhadsomesharpwordsforInternetcompaniesThursday,sayingthattheyarenotexplainingtotheir
Birth,growth,decline,death:itistheusualcycleforpeople,companiesandindustries.Butthestoryofviolin-makinginCre
随机试题
分析图3—4所示逻辑电路的逻辑功能。
寻找准顾客的行为也称为()
患者女性,31岁,孕26周,阴道流血3天,色暗红,伴轻微腹痛。超声检查显示:胎盘位于后壁,胎盘下缘处胎盘与宫壁间可见37mm×21mm高低回声不均匀区,其内未见明显血流信号超声诊断的胎盘早剥多为胎盘的哪一部位出血
患者,35岁,下腹部肿物3年,逐渐增大,自右下腹部开始如拳头大小,现已如妊娠足月大小,但仍能做轻微的家务劳动。最可能的肿瘤为
下列可引起特异性感染的致病菌是
下列人群中,哪类不适宜进行生命质量评价
商业银行公司治理应遵循各治理主体独立运作、有效制衡、相互合作、协调运转的原则。()
皮肤破损出血、颈髓损伤、锐器插人体内、严重挤压伤等是灾害发生时的常见损伤类型,掌握科学的自救方法对于延续生命、等待救援很重要。下列自救措施中,不恰当的是()。
personalindependencetheprocesstheparents’cultureprevailingvaluesA.these【T13】______intheirchildrenB.thecustomsan
A、 B、 C、 D、 C
最新回复
(
0
)