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
Most people are right-handed and children usually have the same handedness as their parents. This suggests that genes are at wor
Most people are right-handed and children usually have the same handedness as their parents. This suggests that genes are at wor
admin
2013-01-20
37
问题
Most people are right-handed and children usually have the same handedness as their parents. This suggests that genes are at work. But identical twins have identical genes, so genes cannot be the whole story. Cultural attitudes seem to have played an important part in the development of hand preferences. In the past, left-handed have suffered anything from teasing to flogging. Even today in some countries en forced right-handedness, particularly for writing and eating, is still common.
To explain the observed patterns of handedness, researchers have devised what is known as a’ geneculture coevolution’ model. The initial assumption of the model-drawn from observation of non-human primates and other mammals such as mice-is that early on in human evolution, the genetic make-up of individuals inclined them to prefer one hand or the other, but that the population was equally divided between right and left-handed people. Over time, according to the model, the interaction of genes and culture has produced a state where everyone has identical genes for handedness. This would happen if, for whatever reason, right-handers were more likely to survive and reproduce. The idea may not be that far fetched. Many biologists believe that handedness is related to brain structure, say, for example, early right-handers may have been better at language.
The model predicts that today everyone has genes which confer a basic predisposition of 78% to be right-handed. How children actually turn out, however, can be influenced by whether their parents are dextral or sinistral. For example, children may mimic their parents. Or parents may influence the handedness of their children in the way that they hand them toys or food.
The researchers reckon that a child with two right-handed parents has a 91% probability of being right-handed; a child with two left-handed parents has a probability of only 63% of being right-handed. But parental influence does not account for everything. Random events during a child’s development can also have a small effect on handedness. Even if identical twins have parents who are both dextral, factors such as their position in the womb may result in the twins not preferring the same hands.
The model seems plausible. It accurately predicts the results of 13 studies of the handedness of twins as well as the proportion of left-handers found in the population at large (roughly 12%, a figure that seems to be quite stable). Asymmetries in early tools, and in the way in which prey were clubbed, suggest that hominids as early as the Australopithecines may have preferred their right hands. Whatever the origin of this dexterous preference, though, left-handers remain at large. Some people are just sinister.
It can be inferred that non-human primates ______.
选项
A、are mostly left-handed
B、are mostly right-handed
C、are equally divided between right-handers and left-handers
D、are good at using both hands
答案
C
解析
文章第二段提到了“model-drawn from observation of non-human primates…the genetic make-up of individuals inclined them to prefer one hand or the other, but that the population was equally divided between right and left-handed people”,因此答案是C。
转载请注明原文地址:https://kaotiyun.com/show/aS2O777K
0
考博英语
相关试题推荐
Thedifferencebetweenaliquidandagasisobvious【l】theconditionsoftemperatureandpressurecommonlyfoundatthesurface
(66)Astateuniversitypresidentwasarrestedtodayandchargedwithimpersonateapoliceofficerbecame,theauthoritiessay,
PeopleintheUnitedStatesinthenineteenthcenturywerehauntedbytheprospectthatunprecedent-edchangeinthenation’sec
Everyyearthousandsofpeoplearearrestedandtakentocourtforshop-lifting.InBritainalone,aboutHK$3,000,000’swortho
Forgatheringdataaboutindividualsorgroupsatdifferentdevelopmentallevels,researcherscanusetworelatedresearchdesig
Mostofthemhadvisitedtheinvalidoftenduringthepastfewmonths,marvelingathis______spiritandhisunfailinggoodtempe
Somecultureshavecustomsthat_____theclothingfashionsofpeopleincertainsocialclasses.
Neitheratthismeetingnoratthepreviousone________theproposal.
Theonlywayheescapedfromthebitterrealitywastolosehimselfinamovie,allowinghisimaginationto______,viewinghimse
Earlwasbalancinghimselfontopofthefencewhenhelosthis_____andfelloff.
随机试题
英国古典经济学家亚当.斯密以制针为例说明以下哪一点的好处( )
A/止血药B/抗凝血药C/抗贫血药D/抗血栓药E/酸碱平衡调节药肝素属于
未经批准擅自开办医疗机构或者非法行医构成犯罪的应承担的是
总承包单位在收到总监理工程师对分包的批准通知后,应尽快与分包单位签订分包协议,并将协议副本报送()备案。
YANGON--MyanmarhasofficiallyacceptedanofferoftheUnitedStatestosendhumanitarianaidtothecountry’scyclonevictims,
案例:某老师讲完溶液的均一性、稳定性后,有位学生提出了这样一个问题:“氯化钠溶于水形成氯离子和钠离子,并在不停地做无规则运动,我们喝了一口该盐水后,由于分子(或离子)运动的不规则性,会不会造成我们喝的那一口盐水中钠离子数量少于(或多于)氯离子数量
《图画展览会》的曲作者是()。
当要求被试在序列记忆任务中不断重复无关的发音时,即时系列回忆的数字广度就减少了,这种现象是
关于IP数据报报头的描述中,错误的是()。
YouwillhearareportpresentedbyajournalistfromTokyo.Foreachquestion(23-30),markoneletter(A,BorC)forthecorrect
最新回复
(
0
)