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
2013-03-22
53
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-handers have suffered anything from teasing to flogging. Even today in some countries enforced 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 ’gene-culture 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 farfetched. 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 par-ents. 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 Australo-pithecines may have preferred their right hands. Whatever the origin of this dextrous preference, though, left-handers remain at large. Some people are just sinister.
According to the "gene-culture coevolution" model, which of the following would be true at the end of the day?
选项
A、A11 people will be right-handed.
B、A11 people will be left-handed.
C、There are as many right-handers as left-handers.
D、People will use both hands equally well.
答案
A
解析
转载请注明原文地址:https://kaotiyun.com/show/8TXd777K
本试题收录于:
公共英语五级笔试题库公共英语(PETS)分类
0
公共英语五级笔试
公共英语(PETS)
相关试题推荐
TheOldGateIntheMiddleAgesthevastmajorityofEuropeancitieshadwallsaroundthem.Thiswaspartlyfordefensive【C1
TheOldGateIntheMiddleAgesthevastmajorityofEuropeancitieshadwallsaroundthem.Thiswaspartlyfordefensive【C1
Peopledon’trealizehowseriousthisrecessionhasactuallybeen.
Obesity(肥胖)CausesGlobalWarmingThelistofillsattributabletoobesitykeepsgrowing:Lastweek,obesepeoplewereaccuse
TheStoryteller1StevenSpielberghasalwayshadonegoal:totellasmanyinterestingstoriestoasmanypeopleaspossibl
TheStoryteller1StevenSpielberghasalwayshadonegoal:totellasmanyinterestingstoriestoasmanypeopleaspossibl
Lastweek,Icalledonmyteacher.
Howdidthestudyevaluateeveryparticipant’ssenseofresponsibility?Accordingtothestudy,whichoneofthepersonalities
Nopeopledoubtthefundamentalimportanceofmothersinchildrearing,butwhatdofathersdo?Muchofwhattheycontributeis
Oursocialdevelopmentwasencouragedthroughteamwork.Weworkedingroupswithpeoplewe’dnevermet【1】.Welearnttolistent
随机试题
“上联:八百里洞庭凭岳阳壮阔;下联:两千年赤壁览黄鹤风流。”这一对联表示的省区分别是:
设p(x)=a0xn+a1xn-1+…+an-1x+an.其中ai(i=0,1,…,n)为实数,a0≠0,n≥1.证明:|p(x)|=+∞.
下面哪些药物不适用于头颈部鳞癌的治疗
与鼻咽癌发生相关的病毒是
下列疾病过程中,红、肿、热、痛、功能障碍表现比较明显的是
PACO2>45mmHg可见于中枢性或外周性呼吸抑制导致肺泡通气不足。()
企业购入资产超过正常信用条件延期付款实质上具有融资性质时,应按购买价款的现值,借记“固定资产”、“在建工程”等科目,按应支付的价款总额,贷记()科目,按其差额,借记“未确认融资费用”科目。
“众里寻他千百度,蓦然回首,那人却在灯火阑珊处。”这是辛弃疾《青玉案.元夕》里的名句,“元夕”指的是()。
根据《中华人民共和国未成年人保护法》的规定,学校、幼儿园的教职员应当尊重未成年人的(),不得对未成年人和儿童实施体罚、变相体罚。
一项任务必须由你和同事共同完成。但是期间你同事接到一个电话说有紧急情况,要请假。你怎么办?
最新回复
(
0
)