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
Twins to Impaired Fertility of Women A woman with a twin brother has fewer children. Twin brothers can leave quite an impres
Twins to Impaired Fertility of Women A woman with a twin brother has fewer children. Twin brothers can leave quite an impres
admin
2013-01-10
46
问题
Twins to Impaired Fertility of Women
A woman with a twin brother has fewer children. Twin brothers can leave quite an impression. The mere presence of a boy in the same womb as his sister causes her to develop bigger teeth than she otherwise would. Girls with twin brothers perform better on spatial-ability tests. They have better ball skills than most females and are more likely to be short-sighted. Now it seems that sharing the womb also has a harmful effect on the sexual reproduction of women with a twin brother.
Virpi Lummaa of the University of Sheffield, in Britain, and her colleagues made the claim after studying detailed data from several generations of church records from many parishes in Finland. They report that women with a twin brother were 15% less likely to get married than were women with a twin sister. Those with a male twin also had a 25% lower chance of giving birth even though they lived just as long as those with a female twin. When the researchers considered only married women, those with a twin brother on average had two fewer children during their lifetimes than did women with a twin sister.
And finally—to rule out any influence of sharing a house as well as a womb—Dr. Lu-mmaa checked the results were the same for women whose twin brothers died before they were three months old. The researchers reported their findings in this week’s Proceedings of the National Academy of Sciences.
As with the teeth, the supposed cause of untypical female biology is early exposure to testosterone. This hormone is made by a male fetus’s developing testes from about seven weeks after conception and is thought to diffuse, thus influencing his sister’s growth. But the exact mechanism by which a twin brother lowers his sister’s chances of reproductive success is unclear.
Dr. Lummaa’s results also suggest that, if a woman wishes to maximize the chances of passing on her genes, she would do better to avoid producing pairs of twins consisting of one boy and one girl and go for a single-sex combination instead. Mothers included in the study who produced opposite-sex twins had 19% fewer grandchildren than did mothers who gave birth to same-sex twins.
Evolutionary theory thus predicts that there should be fewer pairs of girl-and-boy non-identical twins than single-sex pairs of non-identical twins. Whether that is so requires another set of figures. Finnish church records, helpful as they are, do not distinguish non-identical same-sex twins from identical ones. In the eyes of God, unlike those of natural selection, twin girls are created equal.
According to Virpi Lummaa and her colleagues, women with twin brothers______.
选项
A、encounter more difficulties in getting married than only-child women
B、raise two more children during their lifetime than women with a twin sister
C、enjoy a much shorter longevity than women whose female twins died early
D、present a reproduction rate a quarter less than those with a female twin
答案
D
解析
推理判断题。根据Virpi Lummaa和her colleagues定位到第二段。题干考查的是龙凤胎中女性的情况。文中提到相较双风胎中的女性,龙凤胎中的女性生育几率少了25%,即四分之一,此外原文中的giving birth与reproduction为同义表达,故[D]项正确。该段虽提到结婚几率问题,但比较的是龙风胎中的女性和双凤胎中的女性,而非和独生女作比较,[A]项张冠李戴;此外文中提到,相较双凤胎中的女性,龙凤胎中的女性一生中平均少生育两个小孩,[B]项所述与此相反;该段仅提到即使龙风胎中的男性在出生三个月内夭折,龙凤胎中的女性的生育情况仍旧不变,而并未对女性的寿命作讨论,故[C]项错误。
转载请注明原文地址:https://kaotiyun.com/show/hDhK777K
0
专业英语四级
相关试题推荐
ItisobviouslynecessarythatboththePresidentandhisadvisers______downtoearth.
SomecallittheSmartShooter,anewrifleforAmericaninfantrytroopsthatistwoweaponsinone,isaccurateupto1,000yar
Hippiesweremembersofayouthmovementofthe1960’sand1970’sthatstartedintheUnitedStatesandspreadtoCanada,Great
Hippiesweremembersofayouthmovementofthe1960’sand1970’sthatstartedintheUnitedStatesandspreadtoCanada,Great
Waterisanessentialglobalresourceanditisuptoeachofusto______it.
LGCForensics,onaformerRAFbaseindeepestOxfordshire.(Thislabdealsmainlyinchemicalandbiologicaltraces,andDNA.H
LGCForensics,onaformerRAFbaseindeepestOxfordshire.(Thislabdealsmainlyinchemicalandbiologicaltraces,andDNA.H
BlackBerrymakerResearchinMotion(RIM)hascomebottomofalistoftheworld’sgreenestelectronicsfirms.TheCanadian-base
______energyundertheearthmustbereleasedinoneformoranother,forexample,anearthquake.
随机试题
在Word2010中,进行各种文本、图形、公式、批注等搜索可以通过______来实现。
9岁女孩,寒战,高热,咳脓痰2天。查体:体温39.2℃,左肺闻及湿性啰音,X线胸片显示:左肺下叶大片致密阴影,给予抗生素治疗。2天后症状加重,胸痛并呼吸困难,左胸呼吸音降低,胸片示左胸大量胸腔积液。进一步诊断最有价值的方法是:(
针对李甲的起诉,人民法院应如何?人民法院受理案件后,决定采用简易程序审理本案,则下列说法正确的是:
贷款总结评价的内容不包括()。
某企业计划2010年进行某项投资活动,有甲、乙两个备选的互斥投资方案资料如下:(1)甲方案需要一台进口设备,该设备离岸价为10万美元(1美元=7.43元人民币),国际运输费率为7%,国际运输保险费率为3%,关税税率为10%,国内运杂费为5.56万元,预备
假定A公司正在对一个项目进行评价,在估计项目风险时找到一个类似公司B,B公司为一家上市公司,其股票的6值为2,资产负债率为50%,所得税率为33%。A公司的资产负债率为60%,所得税率为30%,则A公司该项目的股东权益β值为1.7521。(
下列情形中,即使以低于成本的价格销售商品,也不属于不正当竞争行为的有()。
1966年,联合国教科文组织在《关于教师地位的建议》中提出,应该把教师工作视为()。
TheAustraliannationaldayissetonJanuary2.6tocommemorate______.
Wecanmakeupourmindsaboutsomepeoplewithinonlysevensecondsofmeetingthem.Publicspeakersoftenconfusetheiraudie
最新回复
(
0
)