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
More boys than girls are born all over the world, but a new study has found that the closer people live to the equator(赤道), the
More boys than girls are born all over the world, but a new study has found that the closer people live to the equator(赤道), the
admin
2017-06-11
41
问题
More boys than girls are born all over the world, but a new study has found that the closer people live to the equator(赤道), the smaller the difference becomes. No one knows why.
The imbalanced sex ratio at birth has been known for more than a hundred years, and researchers have found a large variety of social, economic and biological factors that relate to the sex ratio at birth-war, economic stress, age, diet, selective abortion and more. But latitude(纬度)is a natural phenomenon, unaffected by cultural or economic factors.
To look at the effect of latitude, Kristen J. Navara of the University of Georgia used the latitude of the capital city in 202 countries, as well as 10 years of data on sex ratio at birth and annual variations in day length and temperature. Dr. Navara performed a statistical analysis which showed that there was a significant relation between sex ratios in favor of boys and latitude. African countries produced the lowest sex ratios—50. 7 percent boys—and European and Asian countries had the highest with 51. 4 percent.
There are some possible explanations, but none entirely satisfactory. It could be that there is some survival value in producing more girls in warmer regions, but it is unclear what this might be. There may be genetic or racial differences that could explain it, but the connection persists over so many varied populations that this seems unlikely. Mice also produce more male offspring during shorter days or colder weather, but the reasons in these animals are just as mysterious as they are in humans.
" There’s a possibility that humans might be responding to factors they were programmed to respond to a long time ago-not cultural or socioeconomic, but climate and things like latitude," Dr. Navara said. " What’s interesting is that we may be seeing something that connects us with our animal ancestry. "
What is the purpose of the passage?
选项
A、To tell a mysterious story.
B、To report a scientific experiment.
C、To explain an interesting phenomenon.
D、To argue for a viewpoint.
答案
C
解析
主旨大意题。从整个行文来看,全文在讨论性别比例不均衡的现象,所以答案为C。全文没有任何story,因此选项A不对。文章也没有提到experiment,可排除B。如果文章讨论某一观点,应该有支持和反对的对照,故D也不正确。
转载请注明原文地址:https://kaotiyun.com/show/iNFO777K
0
考博英语
相关试题推荐
Theattemptandoffertocarryoutcloningexperimentonhumanbeingisblameworthyandcanhardlyfindany____amongthepublic
Onanaverageofsixtimesaday,adoctorinHollandpractices"active"euthanasiaintentionallyadministeringalethaldrugto
Watchababybetweensixandninemonthsold,andyouwillobservethebasicconceptsofgeometrybeinglearned.Oncethebabyh
_____somequestionsaboutthebookkeeper’shonesty,thecompanyaskedhimtoleave.
TheParthenonTheParthenon,abuildinginAthens,Greece,isperhapsoneofthemostmemorablestructuresonEarth.Built25c
"Governmentsthatwanttheirpeopletoprosperintheburgeoningworldeconomyshouldguaranteetwobasicrights:therighttopr
Petroleumproducts,suchasgasoline,kerosine,homeheatingoil,residualfueloil,andlubricatingoils,comefromonesource-crude
Becausethechildrenkeepinterruptingherwhenevershereadsabook,sheisalways_____herplace.
Althoughtheprojecthasbeenapproved,manycompaniesfindthecostofimplementationisprohibitivelyexpensive.
【T1】Determinedtomakeitonhisown,Bushdidnottellhisfatherthathewas’applyingtoHarvardBusinessSchool.【T2】The"Wes
随机试题
Usinganon-finiteverbform:Iamsureit’lldoyougoodifyouadmitthatyoumadethemistake.
下列何者不属于内分泌腺:
女,46岁。因外伤导致张力性气胸,留置胸腔闭式引流。引流期间要搬运此病人,正确的做法是
下列乳牙的解剖特点不包括
关于盐酸利多卡因的含量测定方法,下列叙述正确的是( )。
夹套管道系统的夹套管外管介质为( )等。
采用缩短折旧年限的方法,有利于加速成本回收,可使后期成本费用前移,从而使前期会计利润发生后移,在税率不变的情况下可以使企业所得税递延缴纳。以下情况应缩短折旧年限的是()。
下列表述错误的是()。
甲是一名美容专家,医院未经甲同意,将其作为医院美容专家在医院的网站上是有甲的照片和简历,并将甲的名字和简历错误的安放在别的专家的照片旁。则下列说法正确的是()
恩格斯在批评费尔巴哈的形而上学时比喻说,给孩子洗澡,把孩子和脏浴水一块泼掉。恩格斯这一论述()。
最新回复
(
0
)