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
考研
Mammals vary enormously in size, from weighing less than a penny to measuring more than three school buses in length. Some group
Mammals vary enormously in size, from weighing less than a penny to measuring more than three school buses in length. Some group
admin
2017-02-17
37
问题
Mammals vary enormously in size, from weighing less than a penny to measuring more than three school buses in length. Some groups of mammals have become very large, such as elephants and whales,【C1】______others have always been small, like primates. A new theory developed by an international team, led by Jordan Okie,【C2】______an explanation for why and how【C3】______groups of organisms are able to evolve【C4】______sizes, whereas others are not.
The research team【C5】______information on how quickly an individual animal grows and used it to【C6】______how large it may get【C7】______evolutionary time. Their research was published recently.
The new theory developed from the observation that some animals【C8】______fast and die young, while others take their time and mature much later. "Fast" animals-such as mice—breed very quickly, while humans mature slowly and are relatively older when they first have children. The theory【C9】______that those species that are relatively faster are more likely to evolve a large size quicker than slow species, and that their maximum size will be greater.
The research team tested their theory using the【C10】______records of mammals over the last 70 million years, examining the maximum size of each mammal group【C11】______that time, including whales, elephants, seals and primates. They found that their theory was very well【C12】______.
"Primates have evolved very slowly, and never got bigger than 1,000 pounds," said Okie, "The【C13】______was true of whales, which evolved their large size at the fastest【C14】______recorded."
The theory also makes predictions about the relative risks of extinction for large animals【C15】______small. The maximum size of an animal is limited by the rate of mortality in the【C16】______. Because larger animals【C17】______breed less frequently than smaller animals,【C18】______the mortality rate doubles, the maximum size is predicted to be 16 times smaller.
"This is a really surprising【C19】______," said Okie. "It points to another reason why many of the large animals went【C20】______after the last Ice Age, and their high risk of extinction in modern environments."
【C10】
选项
A、specimen
B、fossil
C、disease
D、birth
答案
B
解析
在七千万年以来(over the last 70 million years)的进化过程中,有些哺乳动物已经绝种或者进化成了新物种。所以只能研究他们的“化石”。选B项fossil。
转载请注明原文地址:https://kaotiyun.com/show/skEZ777K
0
考研英语一
相关试题推荐
WhatdoRussia’sBelgorodprovinceandsomeschoolsinFloridaandConnecticuthaveincommon?Theyareunlikelyrecruitstothe
WhatdoRussia’sBelgorodprovinceandsomeschoolsinFloridaandConnecticuthaveincommon?Theyareunlikelyrecruitstothe
WhatdoRussia’sBelgorodprovinceandsomeschoolsinFloridaandConnecticuthaveincommon?Theyareunlikelyrecruitstothe
WhatdoRussia’sBelgorodprovinceandsomeschoolsinFloridaandConnecticuthaveincommon?Theyareunlikelyrecruitstothe
WhatdoRussia’sBelgorodprovinceandsomeschoolsinFloridaandConnecticuthaveincommon?Theyareunlikelyrecruitstothe
WhatdoRussia’sBelgorodprovinceandsomeschoolsinFloridaandConnecticuthaveincommon?Theyareunlikelyrecruitstothe
ForyearsAmericanconversationaboutIraqhasincludedarefrainabouthowwecannotexpecttocreateaJeffersoniandemocracy
IfAmericanmedicinewereapatient,hewouldweigh350poundsandbegainingfast.Despitebeingrepeatedlycounseledaboutthe
Nearlythree-quarteroftheEarthiscoveredwithwater.The【B1】______ofthecontinents,especiallyinthetemperatezones,isv
Nearlythree-quarteroftheEarthiscoveredwithwater.The【B1】______ofthecontinents,especiallyinthetemperatezones,isv
随机试题
在四种典型塔板中,操作弹性最大的是()型。
孕期用药是否导致胎儿畸形的影响因素主要为
根据《建筑工程施工许可管理办法》,下列关于领取施工许可证应当具备的条件表述不准确的是()。
原始凭证不得涂改、刮擦、挖补。原始凭证有错误的,应该由出具单位重开或更正,更正处应当加盖出具单位印章。原始凭证金额有错误的,应当由出具单位重开,不得在原始凭证上更正。()
下列各项中,应确认为资产的是()。
根据《中华人民共和国海关法》的规定,中华人民共和国海关是属于()。
根据我国《中外合资经营企业法》及其实施条例的规定,下列关于合营企业董事长产生方式的表述中,不正确的有()。
如何理解司法独立原则?
BeautyisbigbusinessinChina.Thecountry’scosmeticsmarketisworth$26billionayear,makingitthethird-biggestinthe
SQL中,下列操作不正确的是______。
最新回复
(
0
)