谁杀死了猛犸象

来源 :新概念·英文阅读 | 被引量 : 0次 | 上传用户:l7821744
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
  猛犸象,又名毛象,是一种适合在寒冷气候下生活的动物,在更新世,它广泛分布于包括我国东北部在内的北半球寒带地区。这种动物身躯高大,体披长毛,一对长而粗壮的象牙强烈向上向后弯曲。它的头骨短,顶脊非常高,上下额和齿槽深。
  
  Hungry prehistoric (史前的)hunters, not climate change, drove elephants and mammoths to extinction(消失)during the Pleistocene(更新世)era, new research suggests.
  在更新世时期,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(漫游)the African, Eurasian(欧亚的), and American continents. Today, only two species of elephants are left in South Asia and sub-Saharan Africa. One theory for this dramatic(戏剧性的) demise holds that rapid climate shifts at the end of the most recent major ice age, some 10,000 years ago, altered vegetation(植被) and broke up habitats, causing the death of those unable to adapt to the new conditions. Another hypothesis (假设)blames prehistoric humans, whose improved weapons and hunting techniques allowed them to wipe out whole herds of elephants and mammoths.
  历史上至少有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、破坏了它们生存的栖息地,大部分大象和猛犸象难以适应新的环境,以致灭绝。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 (考古学家)Todd Surovell of the University of Wyoming(怀俄明州), Laramie, and his colleagues tested two assumptions(假设). If humans caused the elephant and mammoth extinctions, Surovell reasoned, the timing 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 (殖民)by humans and would only begin to die off once climate change occurred.
  为了解决这场争议,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,那么特定地区的大象和猛犸象的灭绝情况应与人类在该地区的扩张相一致。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 where and when elephants and mammoths were killed. In all, the study included 41 archaeological(考古学的) sites on five continents. The researchers found that, as humans migrated (移动)out of Africa, they left a trail of dead elephants and mammoths on their way. The creatures disappear from the fossil (化石)record of a region once it became colonized by humans. Modern elephants survived in refuges uninviting to humans, such as tropical(热带的) forests, said Surovell.
  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。
  Biologist(生物学家) R. Dale Guthrie of the University of Alaska (阿拉斯加州)in Fairbanks largely agrees on the findings, but he says more work is needed to explain why some mammoths seem to have survived in regions colonized(拓殖) by humans and why many modern elephants live in areas easily accessible to humans, such as the African savannah(大草原).
  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。
   编辑:于赫
  
其他文献
请下载后查看,本文暂不支持在线获取查看简介。 Please download and view, this article does not support online access to view profile.
期刊
记得小时候,我最喜欢和母亲在一起。因为母亲就像是我的保护伞,我可以在她怀里撒娇或是任性地吵闹,尤其当她拉着我的小手对我微笑时,我觉得她就像天使一样美丽。母亲的爱给了我无限温暖。  然而,随着年龄的增长,再加上母亲调到外地就职,我们俩相处的时间越来越少了。就算偶尔有相处的时间,我也不太愿意和她交谈,因为我们的意见和看法总会有分歧。比如说到极限运动时,我觉得那些玩蹦极和攀岩的人很酷,而母亲总说这些人太
期刊
期刊
1rn浙江省金华市曹宅镇洪村王勇的父亲在给人家拆旧房时,被突然倒塌的砖墙砸死.痛失父爱和越来越困窘的家境,使王勇的性格越来越孤僻.不久,初中没念完,他便辍学了.
New Year’s celebrations around the world include foods that many people believe will bring good fortune in the year to come. These beliefs are a kind of folklore-ideas passed down from one generation
期刊
在日本,—位父亲带着6岁的儿子去郊游。父亲钓鱼,儿子在一边玩耍。在离湖边不远的地方,有一个很深的大坑。儿子好奇,自己偷偷下到坑里。玩了一阵子后,他发现大坑离地面很远,
期刊
用 32对引物组合对水稻 (OryzasativaL .)珍汕 97不育系与保持系的总DNA进行AFLP分析 ,显示出 88个差异带。其中 ,引物组合EcoRⅠ_AAC×MseⅠ_CTC产生的差异片段———珍汕 9
2005年1月14日,蒋光喜走进了回龙镇派出所报案:我家的房屋被烧毁了,你们一定要为我作主啊!派出所民警得知情况后立即向开江县公安消防大队报告,情况迅速引起了公安干警的高度
根据Ⅰ类和Ⅱ类SLG基因两端序列合成了特异引物 ,对西南农业大学和HRI (HorticultureResearchInterna tional,Wellesbourne)提供的不同亲和指数的甘蓝 (BrassicaoleraceaL .)