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
The human species came into being at the time of the greatest biological diversity in the history of the Earth. Today, as human
The human species came into being at the time of the greatest biological diversity in the history of the Earth. Today, as human
admin
2014-01-17
47
问题
The human species came into being at the time of the greatest biological diversity in the history of the Earth. Today, as human populations expand and alter the natural environment, they are reducing biological diversity to its lowest level. The ultimate consequences of this biological reduction are beyond calculation, but they are certain to be harmful. That, in essence, is the biodiversity crisis.
The history of global diversity can be summarized as follows: after the initial flowering of multi-cellular animals, there was a swift rise in the number of species in early Paleozoic times (between 600 and 430 million years ago), then plate-alike stagnation for the remaining 200 million years of the Paleozoic era, and finally a slow but steady climb through the Mesozoic and Cenozoic eras to diversity’s all-time high. This history suggests that biological diversity was hard won and a long time in coming. Furthermore, this pattern of increase was set back by five massive extinction episodes. The most recent of these, during the Cretaceous period, is by far the most famous, because it ended the age of the dinosaurs, giving hegemony to the mammals, thus ultimately making possible the dominance of the human species over the Earth. But the Cretaceous crisis was minor compared with the Permian extinctions 240 million years ago, during which between 77 and 96 percent of marine animal species perished. It took five million years, well into Mesozoic times, for species diversity to begin a significant recovery.
Within the past 10,000 years biological diversity has entered a wholly new era. Human activity has had a devastating effect on species diversity, and the rate of human-induced extinctions is accelerating. Half of the bird species of Polynesia have been eliminated through hunting and the destruction of native forests. The list of such biogeographic disasters is extensive.
Because every species is unique and irreplaceable, the loss of biodiversity is the most profound process of environmental change. Its consequences are also the least predictable because the value of the Earth’s species remains largely unstudied and unappreciated; unlike material and cultural wealth, which we understand because they are the substance of our everyday lives, biological wealth is usually taken for granted. This is a serious strategic error, one that will be increasingly regretted as time passes.
What is said about material and cultural wealth in the passage?
选项
A、Because we can readily assess their value, we tend to take them for granted.
B、Some of them may have to be sacrificed if we are to protect our biological heritage.
C、They are of less value than biological wealth because they have evolved over a shorter period of time.
D、Their value is more visible and easier to access and appreciate than biological wealth.
答案
D
解析
最后一段第二句的后半部分提到,不像我们理解的物质财富和文化财富,是因为它们是我们日常生活中的必需品,而我们想当然的认为生物物种的财富也是这样。这句话的隐含义是讲,生物物种的财富不像物质财富和文化财富那样容易接触到,再根据第84题的题解可知答案为D 。
转载请注明原文地址:https://kaotiyun.com/show/ccFK777K
0
专业英语四级
相关试题推荐
Norrishasdecidedto_________forsomeeveningclassesnexttermnowthathehassettleddowninNewYork.
Weatherpermitting,we’llhaveapicnicthisweekend.Theitalicizedphrasesindicates______.
Asitwas,theDemocratswouldcontrolthefederalgovernment______becauseofthedivisionamongtheiropponents.
Whatcomestomindwhenyouheartheword—diversity?Issuesofraceorgendermayspringtomind.Equalrights?Orminorityissu
Whatcomestomindwhenyouheartheword—diversity?Issuesofraceorgendermayspringtomind.Equalrights?Orminorityissu
Atthelastcommitteemeeting,themotionthatthesaleofthealcohol______unlawfulwasdefeated.
Hespokeso______thatevenhisopponentswerewonoverbyhisarguments.
Formanyyears,wehavebeenledtobelievethataperson’sintellectualintelligenceisthegreatestpredictorofsuccess.Soci
随机试题
A.肾阳虚衰B.湿邪困脾C.脾肾阳虚D.外邪侵袭E.脾胃湿热头面先肿,继而波及全身,小便短少,发热恶风者,多因
下列关于票据权利的取得说法正确的有:()
设计如题图所示的二柱矩形联合基础。基础材料是:混凝土C20,HRB335钢筋。已知柱1、柱2截面均为bc×hc=300mm×300mm。要求基础左端与柱1外侧面对齐,已确定基础埋深为1.20m。基础宽b=1000mm,高h=500m,柱上作用有竖向力F1、
背景材料: 为加强对公路工程设计变更的管理,《公路工程设计变更管理办法》规定: 重大设计变更由交通部负责审批。较大设计变更由省级交通主管部门负责审批。 项目法人负责对一般设计变更进行审查,并应当加强对公路工程设计变更实施的管理。 对一
某公司发行期限为5年的债券,票面利率为6%,每年付息一次,面额为100元,市场同类债券的利率为5%,此债券的价格应为()元。
形成性评价
大量研究表明,几乎所有的合成色素都不能向人体提供营养物质,某些合成色素甚至会危害人体健康,导致生育力下降、畸胎等,有些甚至在人体内可能转换成致癌物质。因此,应该使用天然色素代替合成色素。如下如果为真,最能削弱上述结论的是:
非理性:指在人的认识过程中,不以理性思维为基础的精神要素以及不能被逻辑思维的概念所包含的主体心理形式。以下认识过程属于非理性因素的是()。
设f(x,y)为连续函数,改变为极坐标的累次积分为
WhatdoyouknowaboutMike?
最新回复
(
0
)