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 balance
Being a man has always been dangerous.There are about 105 males born for every 100 females, but this ratio drops to near balance
admin
2015-05-29
53
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 pass 100,000 years-even the pass 100 year 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 used to be the danger in being a man according to the first paragraph?
选项
A、A lack of mates.
B、A fierce competition.
C、A lower survival rate.
D、A defective gene.
答案
C
解析
本题可参照文章的第1段。身为男人,总是有危险。男女出生比率大约为105:100,但到成年时,这种比率下降,几乎达到平衡,在70岁的老年人中,女性比男性多一倍。可是男性死亡率普遍高的现象正在改变。如今的男婴同女婴和存活率一样。这意味着,男孩到了寻找伴侣的关键年龄,将第一时间出现男孩过剩现象。更重要的是,自然选择的另一个偶然性失去了作用。50年前,婴儿(尤其是男婴)存活下来的几率取决于其体重。轻一公斤或重一公斤都几乎代表着必死无疑。体重在今天几乎不起作用。由于很多差别是由基因引起的,因而又一个进化因素消失了。
转载请注明原文地址:https://kaotiyun.com/show/gvLO777K
0
考博英语
相关试题推荐
Everygeologistisfamiliarwiththeerosioncycle.Nosoonerhasanareaoflandbeenraisedalivesea-levelthanitbecomess
Everygeologistisfamiliarwiththeerosioncycle.Nosoonerhasanareaoflandbeenraisedalivesea-levelthanitbecomess
Everygeologistisfamiliarwiththeerosioncycle.Nosoonerhasanareaoflandbeenraisedalivesea-levelthanitbecomess
Anewbiotechnologyprocedurethatcouldbecomecommerciallyavailableinaslittleastwotofouryearsis"transgenosis",whic
Howawfulitwouldbetobeacelebrity,alwaysinthepubliceyes,Celebritiesleadvery.stressfullives,nomatter【51】glamoro
Howawfulitwouldbetobeacelebrity,alwaysinthepubliceyes,Celebritiesleadvery.stressfullives,nomatter【51】glamoro
Signsofdeafnesshadgivenhimgreatanxietyasearlyas1798.Foralongtimehesuccessfullyconcealeditfromallbuthismo
Signsofdeafnesshadgivenhimgreatanxietyasearlyas1798.Foralongtimehesuccessfullyconcealeditfromallbuthismo
Signsofdeafnesshadgivenhimgreatanxietyasearlyas1798.Foralongtimehesuccessfullyconcealeditfromallbuthismo
随机试题
有如下程序:#includeusingnamespacestd;classBase{public:Base(intx=0){cout
患者,男,29岁。发现血压升高2~3年,血压最高180/100mmHg,尿常规检查示尿蛋白(++),血生化检查示血肌酐642μmol/1,最可能的诊断是
一日,甲带邻家男孩乙到公园玩,甲想“吓唬”乙一下,就提着他的双脚将其倒悬于一座桥的栏杆外,乙边喊“饶命”边挣扎,甲手一滑,乙掉入河中,甲急忙去救,乙已溺水而亡,甲对乙的死亡结果在主观上所持的心理态度是:()
根据《期货公司管理业务试点办法》,下列人员可以作为期货公司资产管理业务客户的是()。
某企业月初结存材料的计划成本为250万元,材料成本差异为超支45万元;当月入库材料的计划成本为550万元,材料成本差异为节约85万元;当月生产车间领用材料的计划成本为600万元。当月生产车间领用材料的实际成本为()万元。
小亮3岁半,在幼儿园里,他很喜欢搭积木,每当有人问谁搭得漂亮时,他总是说自己搭得好,而事实并非如此。问题:请结合幼儿自我评价的有关原理加以分析。
根据《中华人民共和国宪法》的规定,处理全国人大常委会的重要日常工作的机关是()。
一古代算数例题:“今有大夫、不更、簪袅、上造、公士凡五人。共猎得五鹿,欲以爵次分之,问各得几何?”书中记载正确的答案是:他们依次分别得到5/3、4/3、1、2/3、1/3只鹿。请问,这道算数题反映了古代中国社会的哪项特色?
下列单位或个人可以成为纳税保证人的有()。
若f(x1,x2,x3)=2x12+x22+x32+2x1x2-tx2x3是正定二次型,则t的取值范围是________.
最新回复
(
0
)