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
Single mums are better at raising their kids than two parents—at least in the bird world. Mother zebra finches have to work hard
Single mums are better at raising their kids than two parents—at least in the bird world. Mother zebra finches have to work hard
admin
2011-01-10
65
问题
Single mums are better at raising their kids than two parents—at least in the bird world. Mother zebra finches have to work harder and raise fewer chicks on their own, but they also produce more attractive sons who are more likely to get a mate.
The finding shows that family conflict is as important an evolutionary driving force as ecological factors such as hunting and food supply. With two parents around, there’s always a conflict of interests, which can have a detrimental effect on the quality of the offspring.
In evolutionary terms, the best strategy for any parent in the animal world is to find someone else to care for their offspring, so they can concentrate on breeding again. So it’s normal for parents to try to pass the buck to each other. But Ian Hartley from the University of Lancaster and his team wondered how families solve this conflict, and how the conflict itself affects the offspring.
To find out, they measured how much effort zebra finch parents put into raising their babies. They compared single females with pairs, by monitoring the amount of food each parent collected, and removing or adding chicks so that each pair of birds was raising four chicks, and each single mum had two--supposedly the same amount of work.
But single mums, they found, put in about 25 percent more effort than females rearing with their mate. To avoid being exploited, mothers with a partner hold back from working too hard if the father is being lazy, and it’s the chicks that pay the price. "The offspring suffer some of the cost of this conflict," says Hartley.
The cost does not show in any obvious decrease in size or weight, but in how attractive they are to the opposite sex. When the chicks were mature, the researchers tested the "fitness" of the male offspring by offering females their choice of partner. Those males reared by single mums were chosen more often than those from two-parent families.
Sexual conflict has long been thought to affect the quality of care given to offspring, says zoologist Rebecca Kilner at Cambridge University, who works on conflict of parents in birds. "But the experimental evidence is not great. The breakthrough here is showing it empirically."
More surprising, says Kilner, is Hartley’s statement that conflict may be a strong influence on the evolution of behaviour, clutch size and even appearance. "People have not really made that link," says Hartley. A female’s reproductive strategy is usually thought to be affected by hunting and food supply. Kilner says conflict of parents should now be taken into account as well.
According to Hartley, which of the following is NOT influenced by sexual conflict?
选项
A、The evolution of the offspring’s behaviour.
B、The look of the offspring’s faces.
C、The number of eggs produced by one offspring at a time.
D、The offspring’s body size.
答案
D
解析
转载请注明原文地址:https://kaotiyun.com/show/89cO777K
本试题收录于:
NAETI中级口译笔试题库外语翻译证书(NAETI)分类
0
NAETI中级口译笔试
外语翻译证书(NAETI)
相关试题推荐
TheancientJewishpeopleregardedthemselvesasthesaltoftheearth,thechosenfewbyGodtoruletheworld.
BritainoccupiedJavaduringtheNapoleonicWars.BoththeBritishandlatertheDutchtriedtocentralizeandreformJava’sadm
Inonesense,wecantracealltheproblemsoftheAmericancityback【C1】______asinglestartingpoint;weAmericansdon’tlike
Machinesthatusehydraulicpressureincludingelevators,dentistchairs,andautomobilebrakes.
Thetrafficpolicestoppedthreetrucksheavilyloadingwithmerchandisethatlookedasgrainbags.
Theprisoner______thathehadassaultedapoliceman.
Adozenyearsago,JamesGrant—oneofthewisestcommentatorsonWallStreet—wroteabookcalledTheTroublewithProsperity
Theirbeliefinredistributionandcentralplanningrevealsastrongurgetostifleopportunitiesandamistrustofindividuale
InDecember,WaymoLLC,theleadingdriverlesscarcompany,broughtouttheworld’sfirstcommercialrobo-taxiservice.Butfor
1986年全国人大常委会副委员长班禅喇嘛在西康地区大法会上教诲信徒们,要爱惜民族团结,维护祖国统一。在中国,公民的信仰自由受到法律保护。目前全西藏在寺僧尼约有14,000多人,另有800位宗教界人士在各级人大、政协、佛教协会和政府部门中工作。
随机试题
患者,男性,21岁,近半年来反复心悸、胸痛、劳力性呼吸困难,时有头晕或短暂神志丧失。体检发现:心脏轻度增大,心尖部有2级收缩期杂音和第4心音,胸骨左缘第3~4肋间闻及较粗糙的喷射性收缩期杂音。应选用的药物是()
消火栓沿道路设置时,消火栓距路缘不大于2m,距建(构)筑物外墙不小于()m。
回购协议实质上是资金余缺双方的一种()证券的借贷交易。
当执行一项集中化战略时,企业并不能达到()的目的。
某企业与小叶订立了一份期限为三年的劳动合同。根据《劳动合同法》的规定,双方可以约定的试用期限最长为()。
读下面两幅“等高线地形图”,回答问题。下列叙述正确的是()。①M点在N点的东北方;②M点在N点的西北方;③M点的海拔可能是58米;④N点的海拔可能是58米
1903年,美国心理学家()出版了《教育心理学》,这是西方第一本以教育心理学命名的著作。
新的国家安全观包括
下面程序的输出结果为:Base::fun,请将程序补充完整。#include<iostream.h>classBase{public:【】fun(){cout<<"Base::fun"<<end1:}classDeri
ThecountryinwhichIlivehaslawsforbiddingdiscriminationonthegroundsofethnicity,religion,sexualityorsex.We’veco
最新回复
(
0
)