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
Spot the difference A Taxonomic history has been made this week, at least according to the World Wildlife Fund (WWF), a conserv
Spot the difference A Taxonomic history has been made this week, at least according to the World Wildlife Fund (WWF), a conserv
admin
2011-01-14
68
问题
Spot the difference
A Taxonomic history has been made this week, at least according to the World Wildlife Fund (WWF), a conservation group. Scientists have described a new species of clouded leopard from the tropical forests of Indonesia with spots (or "clouds", as they are poetically known) smaller than those of other clouded leopards, with fur a little darker and with a double, as opposed to a "partial double"—stripe down its back.
B However, no previously unknown beast has suddenly leapt out from the forest. Instead, some scientists have proposed a change In the official taxonomic accounting system of clouded leopards. Where there were four subspecies there will likely now be two species. A genetic analysis and a closer Inspection of museum specimens’ coats published in Current Biology has found no relevant difference between three subspecies described 50 years ago from continental Asia and from the Halnan and Taiwan islands. The 5000-11000 clouded leopards on Borneo, the 3000-7000 on Sumatra, and the remaining few on the nearby Batu Islands can now, the authors say, claim a more elevated distinction as a species.
C What this actually means is fuzzy and whether it is scientifically important is questionable. In any case, biologists do not agree what species and subspecies are. Creatures are given Latin first and second names (corresponding to a genus and species) according to the convention of Carl yon Llnné, who was born 300 years ago this May. But Linnaeus, as he Is more commonly known, thought of species as perfectly discrete units created by God. Darwinism has them as mutable things, generated gradually over time by natural selection. So delineating when enough variation has evolved to justify a new category is largely a matter of taste.
D Take ants and butterflies. Ant experts have recently been waging a war against all types of species subdivision. Lepidopterists, on the other hand, cling to the double barrel second names from their discipline’s 19th century tradition, and categorise many local subclasses within species found over wide areas. Thus it would be futile if one were so inclined—to attempt to compare the diversity of ant and butterfly populations.
E The traditional way around the problem is to call a species all members of a group that share the same gene pool. They can mate together and produce fertile offspring. Whether Indonesian clouded leopards can make cubs with continental ones remains unknown but seems probable. Instead, the claim this week is that genetics and slight differences In fur patterning are enough to justify re-branding the clouded leopard as two significant types. Genetically, that makes sense if many DNA variations correlate perfectly between members of the two groups. The authors did find some correlation, but they looked for it in only three Indonesian animals. A larger sample would have been more difficult.
F One thing Is abundantly clear: conservationists who are flying to stop the destruction of the leopards’ habitat in Borneo and Sumatra see the announcement of a new species of big cat as a means to gain publicity and political capital. Upgrading subspecies to species is a strategy which James Mallet, of University College London, likes to call species inflation. It is a common by-product of genetic analysis, which can reveal differences between populations that the eye cannot, Creating ever more detailed genetic categories means creating smaller and increasingly restricted populations of more species. The trouble is that risks devaluing the importance of the term species.
G The problem of redefining species by genetics is the creation of taxonomic confusion, a potentially serious difficulty for conservationists and others, Take for example the recent proposal to add the polar bear to the list of animals protected under America’s Endangered Species Act. That seems all well and good. However, study the genetics and it transpires that polar bears are closer to some brown bears, than some brown bears are to each other. Go by the genes and it seems that the polar bear would not count as a species in its own right (and thus might not enjoy the protection afforded to species) but should be labelled a sub-species of the brown bear.
*
选项
答案
Not Given
解析
转载请注明原文地址:https://kaotiyun.com/show/EaVO777K
本试题收录于:
雅思阅读题库雅思(IELTS)分类
0
雅思阅读
雅思(IELTS)
相关试题推荐
SurilandcannotbothexportwheatandkeepbreadplentifulandaffordableinSuriland.Accordingly,Suriland’swheatfarmersar
Advertisement:Today’scustomersexpecthighquality.Everyadvanceinthequalityofmanufacturedproductsraisescustomerexpe
Agroupcancharteraparticularaircraftatafixedtotalcost.If36peoplechartertheaircraftratherthan40people,thent
LICENSE:BUSINESS::
WhileexaminationofEisenstein’sworkhasyieldedbetterunderstandingsoffilmtheory,suchattentionisrarelygranted
Darwinproposedthetheoryofsexualselectiontoexplaintheoriginofostentatiousplumageincertainbirdspecies,maint
Manynutritionists,havingknownfordecadesthatsaturatedfat,foundinabundanceinredmeatanddairyproducts,raise
Manynutritionists,havingknownfordecadesthatsaturatedfat,foundinabundanceinredmeatanddairyproducts,raise
Thephysicsofelementaryparticlesisnotoriousforthefancifulnessofitsterminology,aboundingasitdoesinna
Mostpioneers(i)______thisvalleyontheirjourneytotheWestbecauseitsruggedterrainandfrequentlandslidesmadeita(ii
随机试题
最终贷款人
第一次明确提出“构建社会主义和谐社会”重要概念的党的会议是
肺脓肿的诊断依据是
A.髌上滑囊炎B.膝内外侧副韧带C.髌下脂肪垫肥厚D.髌下滑囊炎E.半月板前角损伤
对隐孢子虫病作病原学检查时检出率最高的方法是
发生以下记账错误时,应选择红字更正法的有()。
“卑鄙是卑鄙者的通行证,高尚是高尚者的墓志铭”,这句诗出自__________之手。
在当下社会,纸币已经出现电子形态,比如越来越多的人使用手机进行支付,整个支付过程完全见不到纸币的踪影。这说明手机支付可以代替货币的哪项职能?
下列影视剧情景设计符合历史常识的是:
美洲印第安文明为什么会被西方侵略者毁灭?
最新回复
(
0
)