Researchers Discover Why Humans Began Walking Upright Most of us walk and carry items in our hands every day. These are seem

admin2016-08-16  47

问题             Researchers Discover Why Humans Began Walking Upright
    Most of us walk and carry items in our hands every day. These are seemingly simple activities that the majority of us don’t question.【B1】______The team of researchers from the U. S. , England, Japan and Portugal investigated the behavior of modern-day chimpanzees as they competed for food resources, in an effort to understand what ecological settings would lead a large ape—one that resembles the 6 million-year old ancestor we shared in common with living chimpanzees—to walk on two legs.
    The research findings suggest that chimpanzees switch to moving on two limbs instead of four in situations where they need to monopolize a resource.【B2】______Over time, intense bursts of bipedal(二足的)activity may have led to anatomical(解剖的)changes that in turn became the subject of natural selection where competition for food or other resources was strong.
    Two studies were conducted by the team in Guinea. The first study was conducted by the team in Kyoto University’s "outdoor laboratory" in a natural clearing in Bossou Forest.【B3】______ The chimpanzees’ behavior was monitored in three situations:(a)when only oil palm nuts were available,(b)when a small number of coula nuts were available,(c)and when coula nuts were the majority available resource.
    When the rare coula nuts were available only in small numbers, the chimpanzees transported more at one time. Similarly, when coula nuts were the majority resource, the chimpanzees ignored the oil palm nuts altogether.【B4】______
    In such high-competition settings, the frequency of cases in which the chimpanzees started moving on two legs increased by a factor of four. Not only was it obvious that bipedal movement allowed them to carry more’ of this precious resource, but also that they were actively trying to move as much as they could in one go by using everything available—even their mouths.
    The second study, by Kimberley Hockings of Oxford Brookes University, was a 14-month study of Bossou chimpanzees crop-raiding, a situation in which they have to compete for rare and unpredictable Resources.【B5】______
A Standing on two legs allows them to carry much more at one time because it frees up their hands.
B But an international team of researchers, including Dr. Richmond from GW’ s Columbian College of Arts and Sciences, have discovered that human walking upright, may have originated millions of years ago as an adaptation to carrying scarce, high- quality resources.
C Here, 35 percent of the chimpanzees’ activity involved some sort of bipedal movement, and once again, this behavior appeared to be linked to a clear attempt to carry as much as possible at one time.
D Human walking on two legs developed as a means of survival.
E Researchers allowed the wild chimpanzees access to different combinations of two different types of nut—the oil palm nut,which is naturally widely available, and the coula nut, which is not. F The chimpanzees regarded the coula nuts as a more highly-prized resource and competed for them more intensely.
【B1】

选项

答案B

解析 文章开篇讲到大多数人对人类直立行走习以为常,并不质疑这种习惯。空格后讲到这组研究者来自美、英、日等国,所以空格处应该提及研究组,故B项“但是一个国际研究者(包括乔治·华盛顿大学哥伦比亚艺术与科学学院的Richmond博士)团队已经发现了人类直立行走可能源于数百万年以前适应搬运稀有的、高质量的资源”在语意和语气上皆适合,当选。
转载请注明原文地址:https://jikaoti.com/ti/YgysFFFM
0

最新回复(0)