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
自考
A New Study on Elephants A recent study of ancient and modern elephants has come up with the unexpected conclusion that the A
A New Study on Elephants A recent study of ancient and modern elephants has come up with the unexpected conclusion that the A
admin
2019-08-15
20
问题
A New Study on Elephants
A recent study of ancient and modern elephants has come up with the unexpected conclusion that the African elephant is divided into two distinct (不同的) species.
The discovery was made by researchers at York and Harvard universities when they were examining the genetic (基因的) relationship between the ancient woolly mammoth and mastodon to modern elephants—the Asian elephant, African forest elephant and African savanna (热带草原) elephant.
Once they obtained DNA sequences from two fossils (化石) , mammoths and mastodons. The team compared them with DNA from modern elephants. They found to their amazement that modern forest and savanna elephants are as distinct from each other as Asian elephants and mammoths.
The scientists used detailed genetic analysis to prove that the African savanna elephants and the African forest elephants have been distinct species for several million years. The divergence (分离)of the two species took place around the time of the divergence of Asian elephants and woolly mammoths. This result amazed all the scientists.
There has long been debate in the scientific community that the two might be separate species but this is the most convincing scientific evidence so far that they are indeed different species.
Previously, many naturalists believed that African savanna elephants and African forest elephants were two populations of the same species despite the elephants’ significant size differences. The savanna elephant has an average shoulder height of 3. 5 metres while the forest elephant has an average shoulder height of 2. 5metres. The savanna elephant weighs between six and seven tons, roughly double the weight of the forest elephant. But the fact that they look so different does not necessarily mean they are different species. However, the proof lay in the analysis of the DNA.
Alfred Roca, assistant professor in the department of Animal Sciences at the University of Minois, said, " We now have to treat the forest and savanna elephants as two different units for conservation purpose. Since 1950 all African elephants have been conserved as one species. Now that we know the forest and savanna elephants are two very distinct animals, the forest elephant should become a bigger priority (优先)for conservation purpose. "
The modern elephants have three species, the Asian elephant, African forest elephant and African savanna elephant.
选项
A、TRUE
B、FALSE
C、Not Given
答案
A
解析
题干要求判断现代大象是否有三个分支,即亚洲大象、非洲森林大象和非洲热带草原大象。第二段最后一句话提到“the Asian elephant,African forest elephant and African savanna elephant”,这三类大象是“modern elephants”的三个分支,所以题干表述是正确的。
转载请注明原文地址:https://kaotiyun.com/show/wakR777K
本试题收录于:
英语(一)题库公共课分类
0
英语(一)
公共课
相关试题推荐
假设选A、B、C三种股票作为样本,当期价格分别为100、150、180,基期价格分别为15、17、18,上市量分别为3000股、5000股、2000股,假定基期指数为1000,则按上市量为权重的加权平均法编制当期股价指数为()
简述合理预期学派的两个基本假设和一个结论。
ManageYour"High-tech"Family①Modernfamilylifeisimprovedonmanylevelsbynumerousadvancesintechnology.However,s
ANewStudyonElephantsArecentstudyofancientandmodernelephantshascomeupwiththeunexpectedconclusionthattheA
"SubstanceAbuse"—SevereAnxietytoSocietyTechnically,anysubstanceotherthanfoodthataltersourbodilyor【W1】______fun
HeritageHomeSchoolChildrenareourfuture,andit’suptoustoarmthemwiththetoolstosucceed.Sadly,today’schild
NuclearPowerIsnuclearpowerreallyamonster?No,definitelynot.Firstofall,nuclearpowerismuchsaferthanothe
"SubstanceAbuse"—SevereAnxietytoSocietyTechnically,anysubstanceotherthanfoodthataltersourbodilyor【W1】________
HeritageHomeSchoolChildrenareourfuture,andit’suptoustoarmthemwiththetoolstosucceed.Sadly,today’schil
HeritageHomeSchoolChildrenareourfuture,andit’suptoustoarmthemwiththetoolstosucceed.Sadly,today’schil
随机试题
减轻辨认控制能力,是指行为人由于精神障碍而对犯罪行为的辨认控制能力明显减弱或者减低。【】
1927年7月中旬,中共中央临时政治局常委会决定了三件大事,其中不包括()
A、苯巴比妥B、司可巴比妥钠C、硫喷妥钠D、异戊巴比妥E、异戊巴比妥钠与甲醛-硫酸反应生成玫瑰红色环的是
冬季,6月龄幼犬突然发病,证见恶寒,耳鼻俱凉,鼻流清涕,湿咳声低,不喜饮水,舌苔薄白,脉象浮紧。针灸治疗可选用的穴位是()
关于股份有限公司的设立,下列哪些表述符合《公司法》规定?(卷三2010年真题试卷第73题)
第三方检测机构是指两个相互联系的主体之外的某个客体,与两个主体没有联系。()
案例:下面为一道物理习题和某同学的解答过程。,题目:如图9所示,铜棒质量m=0.1kg,静止放在相距L=8cm的水平导轨上,两者之间的动摩擦因数μ=0.5。现在铜棒中通以I=5A的电流,要使铜棒滑动,可在两导轨间加一垂直于铜棒的匀强磁场。求所加
下面是一组有关中国革命政权的材料:材料1中华苏维埃第一次全国代表大会谨向全世界与全中国的劳动群众宣布它要在全中国所实现的基本任务,即中华苏维埃共和国的宪法大纲。这些任务,在现在的苏维埃区域内,已经开始实现。但中华苏维埃第一次全国人民
RenewableEnergySourcesTodaypetroleumprovidesaround40%oftheworld’senergyneeds,mostlyfuellingautomobiles.Coal
LiLeiworksinafarmtoolfactory.Heandfiveofhisfriendsareveryinterestedinsinging.Sotheyhave(41)asingingg
最新回复
(
0
)