时间:2019-02-02 作者:英语课 分类:阅读空间


英语课

    Hungry prehistoric 1 hunters, not climate change, drove elephants and wooly 2 mammoths to extinction 4 during the Pleistocene era, new research suggests.


    在约一万年前的更新世,大象和猛犸象从地球上许多地区大量消失。一项新研究表明,导致这场灭绝的并不是气候剧变,而是饥饿的史前猎人。


    At least 12 kinds of elephants and mammoths used to roam the African, Eurasian, and American continents. Today, only two species of elephants are left in South Asia and sub-Saharan Africa. One theory for this dramatic demise 5 holds that rapid climate shifts at the end of the most recent major ice age, some 10,000 years ago, altered vegetation and broke up habitats, causing the death of those unable to adapt to the new conditions. Another hypothesis blames prehistoric humans, whose improved weapons and hunting techniques allowed them to wipe out whole herds 6 of elephants and mammoths (Science, 8 June 2001, p. 1888).


  历史上曾经至少有12种大象和猛犸象漫游在非洲、美洲和欧亚大陆,但现在只剩下亚洲象和非洲象两种。有的科学家认为,在约一万年前的最近一次冰期,地球气候急剧变化,影响植被、破坏栖息地,大部分大象和猛犸象难以适应新的环境,以至灭绝。另一种假设则提出,当时的史前人类掌握了更精良的武器和更娴熟的捕猎技巧,可以猎杀整群的大象和猛犸象,致使其灭绝。


    To help resolve the debate, archaeologist Todd Surovell of the University of Wyoming, Laramie, and colleagues tested two assumptions. If humans caused the elephant and mammoth 3 extinctions, Surovell reasoned, the timing 7 of the die-offs in specific regions should match human expansion into those regions. On the contrary, if the extinction of these mammals were due to climate change, elephants and mammoths should remain in regions already colonized 8 by humans and would only begin to die off once climate change occurred.


  为了解决这个争议,美国怀俄明大学的考古学家Todd Surovell及其同事对以上两种假说进行了检验。Surovell提出,如果主要原因在于人类,那么特定地区大象和猛犸象的灭绝情况应与人类在该地区的扩张一致。相反,如果是气候导致了灭绝,那么在已经有人居住的地区,大象和猛犸象也仍然存在,直到气候变化来临。


    The team tested both theories by analyzing 9 where and when elephants and mammoths were killed. In all, the study included 41 archaeological sites on five continents. The researchers found that, as humans migrated out of Africa, they left a trail of dead elephants and mammoths in their wake. The creatures disappear from the fossil record of a region once it became colonized by humans. Modern elephants survived in refuges uninviting to humans, such as tropical forests, says Surovell, whose team reports its findings online this week in the Proceedings 10 of the National Academy of Sciences.


  为此,研究小组分析了大象和猛犸象被人类捕杀的时间和地点等情况。他们对5大洲41处考古地点进行研究,结果发现,人类走出非洲的途中,身后一路留下大象和猛犸象的遗骸。某一地区一旦有人类居住,这里的大象和猛犸象就开始从化石记录里消失。Surovell提出,现代大象的祖先是因为居住在热带雨林等人类难以到达的地方,才得以存留。有关论文发表在本周的美国《国家科学院学报》(PNAS)上。


    Biologist R. Dale Guthrie of the University of Alaska in Fairbanks largely agrees with the findings, but he says more work is needed to explain why some mammoths seem to have survived in regions colonized by humans and why many modern elephants live in areas easily accessible to humans, such as the African savannah.


  阿拉斯加大学的生物学家R. Dale Guthrie大体上同意这种看法,但认为还需要更多研究来解释一些现象,如猛犸象为何能在有人居住的地方生存,现代大象为何能生活在人类容易到达的非洲大草原等地区。



adj.(有记载的)历史以前的,史前的,古老的
  • They have found prehistoric remains.他们发现了史前遗迹。
  • It was rather like an exhibition of prehistoric electronic equipment.这儿倒像是在展览古老的电子设备。
adj.毛茸茸的;糊涂的
  • I like the feel of this cloth and it has a warm wooly feel.我喜欢这块布的手感,它摸上去毛茸茸的很暖和。
  • He wore a brown t-shirt with jeans and a pair of shoes,with a wooly hat covering his hair.小贝身穿一件棕色t恤,搭配牛仔裤和皮鞋,头戴一顶盖住头发的羊毛帽子。
n.长毛象;adj.长毛象似的,巨大的
  • You can only undertake mammoth changes if the finances are there.资金到位的情况下方可进行重大变革。
  • Building the new railroad will be a mammoth job.修建那条新铁路将是一项巨大工程。
n.熄灭,消亡,消灭,灭绝,绝种
  • The plant is now in danger of extinction.这种植物现在有绝种的危险。
  • The island's way of life is doomed to extinction.这个岛上的生活方式注定要消失。
n.死亡;v.让渡,遗赠,转让
  • He praised the union's aims but predicted its early demise.他赞扬协会的目标,但预期这一协会很快会消亡。
  • The war brought about the industry's sudden demise.战争道致这个行业就这么突然垮了。
兽群( herd的名词复数 ); 牧群; 人群; 群众
  • Regularly at daybreak they drive their herds to the pasture. 每天天一亮他们就把牲畜赶到草场上去。
  • There we saw herds of cows grazing on the pasture. 我们在那里看到一群群的牛在草地上吃草。
n.时间安排,时间选择
  • The timing of the meeting is not convenient.会议的时间安排不合适。
  • The timing of our statement is very opportune.我们发表声明选择的时机很恰当。
开拓殖民地,移民于殖民地( colonize的过去式和过去分词 )
  • The area was colonized by the Vikings. 这一地区曾沦为维京人的殖民地。
  • The British and French colonized the Americas. 英国人和法国人共同在美洲建立殖民地。
v.分析;分析( analyze的现在分词 );分解;解释;对…进行心理分析n.分析
  • Analyzing the date of some socialist countries presents even greater problem s. 分析某些社会主义国家的统计数据,暴露出的问题甚至更大。 来自辞典例句
  • He undoubtedly was not far off the mark in analyzing its predictions. 当然,他对其预测所作的分析倒也八九不离十。 来自辞典例句
n.进程,过程,议程;诉讼(程序);公报
  • He was released on bail pending committal proceedings. 他交保获释正在候审。
  • to initiate legal proceedings against sb 对某人提起诉讼
学英语单词
Achorion lebertii
alkaline reserve
allosyndisis
already-listed
angle of shear resistance
antenna inaequalis
Arbatax
atomic physicss
bar cutting machine
be one for the books
Bellegem
Bhagwan
biis
bilateral bearing
black mould of rice
Blyth Ra.
Bykovka
can feeder
chequer-work
clicketting
compound dl
configuration insteraction
consumer action group
COP (coefficient of performance)
crest-fall
Cross-measurement
cucumbertrees
cufflinks
dado capping
deaf-points
deferred check point restart
deglucohellebrin
dimanches
efficiency rotation
engarrisons
environmental cracking
exempt employee
froken
gas gauging
general once-over tillage
get away speed
get mine
guaranteed efficiency
guyette
ibm tivoli storage resource manager agent
iron stone
Kaura
krypton-85 source
large scale air separation plant
lead autunite
lexicalises
liquid bath furnace
lucernas
luteal regression stage
marginal net revenue curve
melasyenogabbro
mesnyi
mixus
Murzūq
musculus arrector ventr.
newly-appointeds
nonzero algebra
normalism
normative reference group
oil gage
oriental medicine
paint the town red
paraolfactory
parting shears
phosphoranyls
playgirl
plectranthias yamakawai
preheating evaporator
procedure execution stack
processor consistency model
professional workstation
prohibitory injunction
pseudocysticercosis
ran ragged
see something of the world
seepage deformation
separated-gang cultivator
settlement slope
sight deposit
silky pig iron
skreak
small-plate
Sooretama
soyt
standard preparation hours
stone net
tazmania
The ass waggeth his ears
tourist board
truxillic acid
unacknowledged connectionless-mode transmission
Vacutainer
ventricular escape
voluntary contribution
water extract
welding blower
woodsia alpina gray