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
34
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
Thereisnoquestionthattheoldstyleofairpollutioncouldkillpeople.Inoneweekfollowingtheinfamous"peasouper"fogi
"Doesmoneybuyhappiness?It’ssometimessaidthatscientistshavefoundnorelationshipbetweenmoneyandhappiness,butthat’
Therationaleforthegovernment’sinvolvementineachmodeoftransportationisthatastrongtransportationsystemisnecessar
"Governmentsthatwanttheirpeopletoprosperintheburgeoningworldeconomyshouldguaranteetwobasicrights:therighttopr
Inthe_____chapters,theprofessorhastracedtheredefinitionofBritain’sglobalpositioninrecentdecades.
FoodanddrinkplayamajorroleinChristmascelebrationsinmostcountries,butinfewmoresothaninMexico.Manyfamiliesov
Mrs.Thompsongaveusa_____accountofwhathadhappened,that’swhywenolongerbelieveinthesincerityofherutterance.
Everyoneexperiencesfearduringmajorcrisis—suchasfires,automobileaccidents,etc.Somepeopleevenfeelverynervouswhe
Forthispart,youareallowed50minutestowriteacompositionofnolessthan300wordsunderthetitleof"HowtoReducing
Amanescapedfromtheprisonlastnight.Itwasalongtime______theguardsdiscoveredwhathadhappened.
随机试题
大黄具有的功效有
“五脏六腑皆令人咳,非独肺也”出自
A3.89~6.11mmol/LB8.90~10.00mmol/LC≥7.0mmol/LD6.1~7.0mmol/LE≥11.1mmol/L糖尿病患者的随机血糖浓度值是
所有权随()的存在而存续,不得预定所有权的存续期间。
采用爆破排淤填石法改良地基时,爆破排淤设计一定要根据堤身设计断面要求设计合理的爆破参数,如包括线药量、单孔药量、()、布药孔数、药包间距、布药位置、药包在泥面下埋设深度、爆破施工水位等。
背景材料:为规范公路工程施工招标投标活动,保证公路工程施工质量,维护招标投标活动各方当事人合法权益,《公路工程施工招标投标管理办法》中明确指出:公路工程施工招标分为公开招标和邀请招标。采用公开招标的,招标人应当通过国家指定的报刊、信息网
C国旅是C航空的母公司,成立于1981年,业务涉及旅游、航空、酒店预订、机票、会议、展览、商务、因私出入境、体育赛事等行业,是目前国内最具规模的旅游批发商和包机批发商。2005年,主打廉价机票的C航空成立了,C国旅开始逐步推出含有自营航班的远途旅行。C航
2015年全年规模以上港口完成货物吞吐量114.3亿吨,比上年增长1.6%,其中外贸货物吞吐量35.9亿吨,增长1.1%。规模以上港口集装箱吞吐量20959万标准箱,增长4.1%。年末全国民用汽车保有量达到17228万辆(包括三轮汽车和低速货车955万辆)
学习一系列单字后,把学过的与未学过的单字随机混在一起,并呈现给被试,要求被试辨认出学过的单字。这种检查记忆效果的方法是()。(2010年)
下列IPv6地址表示中,错误的是()。
最新回复
(
0
)