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
外语
Being a man has always been dangerous. There are about 105 males born for every 100 females, but this ratio drops to near balanc
Being a man has always been dangerous. There are about 105 males born for every 100 females, but this ratio drops to near balanc
admin
2017-08-15
22
问题
Being a man has always 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 among 70-year-olds there are twice as many women as men. But the great universal of male mortality is being changed now, by babies survive almost as well as girls do. This means that, for the first time, there will be an excess of boys in those crucial years when they are searching for a mate. More important, another chance for natural selection has been removed. Fifty years ago, the chance of a baby (particularly a boy baby) surviving depended on its weight. A kilogram too light or too heavy meant almost certain death. Today it makes almost no difference. Since much of the variation is due to genes one more agent of evolution 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 in some religious communities, very few women has 15 children. Nowadays, the number of births, like the age of death, has become average. Most of us have roughly the same number of offspring. Again, differences between people and the opportunity for natural selection to take advantage of it have diminished. India shows what is happening. The country offers wealth for a few in the great cities and poverty for the remaining tribal peoples. The grand mediocrity of today everyone being the same in survival and number of offspring means that natural selection has lost 80% of its power in upper-middle-class India compared to the tribes.
For us, this means that evolution is over; the biological Utopia has arrived. Strangely, it has involved little physical change. No other species fills so many places in nature. But in the past 100,000 years—even the past 100 years our lives have been transformed but our bodies have not. We did not evolve, because machines and society did it for us. Darwin had a phrase to describe those ignorant of evolution: they "look at an organic being as average looks at a ship, as at something wholly beyond his comprehension". No doubt we will remember a 20th century way of life beyond comprehension for its ugliness. But however amazed our descendants may be at how far from Utopia we were, they will look just like us.
What does the example of India illustrate?
选项
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 the tribes.
D、India is one of the countries with a very high birth rate.
答案
B
解析
本题可参照文章的第2段。从中可知,如今很少人像从前那样能生育了。除了在一些宗教群体,很少有妇女生15个孩子。今天所生孩子的数目就像死亡年龄一样,人人都差不多。我们大多数人家的子女数量几乎都一样多。人与人之间的差异和利用差异进行自然选择的机会再次减小。印度的情况就是这样。该国为大城市的一部分人提供财富,而其余那些仍保持群居的部落民族依然贫困。今天最大的相同点——每个人的生存机会和子女数量都一样——意味着,与部落比较,自然选择在印度中上阶层已失去80%的作用。据此可知,印度的例子说明——在印度,自然选择在穷人和富人之间所起的作用大大降低了。B项与文章的意思相符,因此B项为正确答案。
转载请注明原文地址:https://kaotiyun.com/show/MZFO777K
0
考博英语
相关试题推荐
For【C1】______thebloodshedandtragedyofD-Day,thebeachesofNormandywillalwaysevokeacertain【C2】______:ayearningfora
Doyouagreeordisagreewiththefollowingstatement?Peopleneversatisfiedwithwhattheyhave.Theyalwayswantsomethin
Evenbeforeheis80,theagingpersonmayundergoanotheridentitycrisislikethatofadolescence.Perhapstherehadalsobeen
Homeschoolingappearstobeagreatsuccessformiddle-classandwealthyfamilieswhenoneparentishomemostofthetime.How
ThecurrentemergencyinMexicoCitythathastakenoverourlivesisnothing.Icouldeverhaveimaginedformeormychildren.
Inrecentyears,manyAmericansofbothsexesandvariousageshavebecomeinterestedinimprovingtheirbodies.Theyhavebecom
Inrecentyears,manyAmericansofbothsexesandvariousageshavebecomeinterestedinimprovingtheirbodies.Theyhavebecom
Ihearmanyparentscomplainingthattheirteenagechildrenarerebelling.Iwishitwereso.Atyourageyououghttobegrowin
PassengerjetsofJapan’saircarrierAllNipponAirwaysareseenparkedonthetarmacatTokyoInternationalAirportin2008.T
Havinga(n)______attitudetowardspeoplewithdifferentideasisanindicationthatonehasbeenwelleducated.
随机试题
Q867气液联动球阀是通过执行机构的()带动球体转动,实现开关。
A、心电图B、动态心电图C、心电图运动负荷试验D、冠状动脉造影E、超声心动图明确和量化诊断二尖瓣狭窄最可靠的方法是
胎儿完成内旋转动作是指
患儿,5岁。舌苔花剥,经久不愈,状如“地图”。病机多为
材料预算价格是指材料由其交货地运到()后的价格。
根据《票据法》的规定,汇票出票人依法完成出票行为后即产生票据上的效力。下列表述中,正确的是()。
初二学生刘浩沉迷于网络游戏,上课不是迟到就是无精打采。班主任吴老师了解过情况后,并没有指责他的行为而是与他聊起了网络游戏,肯定他的兴趣和特长,指出沉迷网络游戏的危害,要求他不能因此而影响了学习。同时在班上成立了电子竞技小组,让他担任组长,除了开展电子竞技的
我国《刑法》规定的完全不负刑事责任的年龄为不满()。
宪法作为国家的根本法要求其必须具有更高的稳定性,因此宪法的修改程序相对于其他法律也是更为严格的。我国宪法的修改权由()行使。
以下关于存储管理单元(MMU)的说法中,错误的是_______。
最新回复
(
0
)