首页
登录
职称英语
[originaltext] When I tell people what my particular branch of science is, I
[originaltext] When I tell people what my particular branch of science is, I
游客
2023-12-22
33
管理
问题
When I tell people what my particular branch of science is, I often get funny looks. In a way, I understand because astrobiology is the study of life on other planets. Well, obviously, life has not been discovered on other planets, which would appear to make astrobiology a science without a subject! However, everything we know about life on our own planet suggests we have to try to understand if there are any universal requirements for life to evolve, as well as the processes involved in evolution. Consequently, scientists are deeply interested in the beginnings of life on Earth. Once we know more about what happened on home ground, as it were, we will be in a better position to understand any life forms we may one day find on other planets.
When most people think of extra-terrestrial life, they conjure up images of so-called "higher" life forms: they imagine humanoid creatures or bizarre and probably dangerous animals of some kind. But if we consider the whole history of life on Earth, a very different picture emerges. For billions of years the only forms of life on the planet were organisms consisting of single cells. It was only about 550 million years ago that the seas suddenly became filled with a whole array of multicellular life.
So how do humans fit into this time frame? Well, human-like creatures first appear in the fossil record about five or so million years ago: in geological terms, this is just a blink of an eye compared to the long history of life on Earth. And Homo sapiens, our own species, has only been around for about 130,000 years. The point is if we do find life on other planets, it will almost certainly be relatively simple, of the sort that populated the Earth for most of its existence so far.
And of course, we must be prepared for these life forms to look very different from life on Earth. We must not forget that many modern life forms came about as a result of chance, their fate shaped by floods, continental drift and comet or meteor strikes. It is interesting to reflect that if a giant asteroid had not hit the Earth and wiped out the dinosaurs, they might still be ruling the planet and we might never have evolved.
Question No. 16 Which of the following does astrobiology study?
Question No. 17 When telling people what branch of science he studies, why does the speaker often get funny looks?
Question No. 18 With what life forms did the seas suddenly become filled some 550 million years ago?
Question No. 19 For how long has Homo sapiens, our own species, has been existing on Earth?
Question No. 20 Many modern life forms came about as a result of a series of chance factors. Which of the following is NOT one of these factors mentioned in the talk?
选项
A、Organisms of single cells.
B、Humanoid creatures.
C、Multi-cellular organisms.
D、Bizarre or perhaps dangerous animals.
答案
C
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3295119.html
相关试题推荐
Ifpeoplecannotaffordtobuytheirownhouse,theycanrentpropertyfromapr
Thepresentsituationofpeople’sabnormalbehaviorsspeaksvolumesforthefact
Whereanypeoplehavemadeatemporaryapproachtosuchacharacter,ithasbeen
Thereportercomparesahusbandtoaparticularlytrickymusicalinstrument,one
Modernindustrialsocietygrantslittlestatustooldpeople.Infact,such
Modernindustrialsocietygrantslittlestatustooldpeople.Infact,such
Modernindustrialsocietygrantslittlestatustooldpeople.Infact,such
Wheneverwehearofanaturaldisaster,wefeelsympathetictothepeopletobe
ThehappiestpeopleintheworldmayliveinScandinavia,anewstudysugges
ThehappiestpeopleintheworldmayliveinScandinavia,anewstudysugges
随机试题
Makesuretheironisn’ttoohot______you’llburnthecloth.A、andB、orC、yetD、s
UNICEFisjoiningwitha【T1】________grouptobringAIDS-preventionprograms
[originaltext]Historically,thecorrelationbetweeneducationandincomeha
Man-madeclimatechangeis"unequivocal(毋庸置疑的)"anddemandsurgentaction.Y
甲乙合伙经营一家服装店,根据合伙协议,甲可代理乙与第三人签订合同,这种代理属于(
住宅地下室车库车道和车位净高分别不小于( )。A.2.20m;2.20m B
()依法对电信和互联网等信息通信服务实行监管,承担互联网行业管理责任;督促电信
计算机测控装置屏蔽控制电缆,采用的屏蔽材料有()。A、对绞铝塑复合膜 B、玻璃
阴阳的本性和维持事物或现象协调发展的内在机制是A.阴阳交感 B.阴阳自和 C
下列工程中,属于概算指标编制对象的是()。A.分项工程 B.单位工程
最新回复
(
0
)