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
80
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. "
Dr. Navara reached her conclusion through______.
选项
A、comparing data
B、field study
C、conducting a survey
D、map reading
答案
A
解析
细节理解题。从第三段的“Kristen J.Navara of the University of Georgia used thelatitude of the capital city in 202 countries,as well as 10 years of data on sex ratio at birth andannual variations in day length and temperature”可知,Navara在研究中引用了data,由此可判断A正确。本段的最后一句:African countries produced the lowest sex ratios一50.7 percentboys—and European and Asian countries had the highest with 51.4 percent就是最佳的证明。而其他三项文章均未提及。
转载请注明原文地址:https://kaotiyun.com/show/4NFO777K
0
考博英语
相关试题推荐
St.Paulhastransformedsoaringenergycostsintoagoldenopportunityforeconomicdevelopmentbyputtingthefinaltoucheson
Theriverisalready_____itsbanksbecauseofexcessiverainfallandthecityisthreatenedwithalikelyflood.
AWorldWithoutBooksOrMusicIfbookshadneverbeendiscovered,manwouldhavefoundsomeotherwayofrecordinghiscomm
Watchababybetweensixandninemonthsold,andyouwillobservethebasicconceptsofgeometrybeinglearned.Oncethebabyh
Atallageandatallstagesoflife,fearpresentsaproblemtoalmosteveryone."Wearelargelytheplaythingsofourfears,"
SharepricesontheStockExchangeplungedsharplyinthemprningbut____slightlyintheafternoon.
Forgatheringdataaboutindividualsorgroupsatdifferentdevelopmentallevels,researcherscanusetworelatedresearchdesig
Tenminuteslater,thepolicecameand______thecrowd.
Thesoldierswere______fromleavingthecampafterdark.
随机试题
两组数据作均数差别的t检验,要求数据分布近似正态,并要求
施工单位拟向某租赁公司承租一台设备,设备价格为120万元,租期与设备寿命期均为6年,每年年末支付租金,折现率为10%,附加率为4%,按照附加率法计算,每年应缴纳租金为()万元。
“利润分配”账户属于所有者权益类账户,用以核算企业当期实现的净利润(或发生的净亏损)。()
外贸经营和收用货单位办理《实施安全质量许可制度的进口商品目》内商品进口手续前,应同时向国外厂商或者代理人申请办理并获得进口安全质量许可后,才能签定进口贸易合同。( )
下列指标中,用于反映客户在一定时期财务状况良好程度的是( )。
下列各项因素中,能够影响无风险报酬率的有()。
如果董事会和监事会不仅抵制注册会计师的沟通,而且在出现意见分歧时以解聘注册会计师相威胁,在这种情况下,注册会计师可能需要与()进行沟通。
导游服务分为全程陪同服务和地方游览讲解服务始于第二次世界大战以后。()
以下对依法治校的认识错误的是()。
ItisthefirstofseveralagreementstheUnitedStateshopestoreachasitattemptstoreducelaborcostsby$5.8billionand_
最新回复
(
0
)