首页
登录
职称英语
When less was known of animals and plants, the discovery of a new species wa
When less was known of animals and plants, the discovery of a new species wa
游客
2025-01-30
18
管理
问题
When less was known of animals and plants, the discovery of a new species was the great object. This is now almost the lowest kind of scientific work. The discovery of a new species as such does not change a feature in the science of natural history. It is merely adding to the enumeration of objects.
We should look rather for the fundamental relations among animals; the number of species we may find is of importance only if they explain the distribution and limitation of different
genera
and families, their relations to each other and to the physical conditions under which they live. The origin of life is the great question of the day. How did the organic world come to be as it is? How did Brazil come to be inhabited by the animals and plants now living there? Who were its inhabitants in past times? What reason is there to believe that the present condition of things in this country is in any sense derived from the past?
The first step in this investigation must be to ascertain the geographical
distribution
of the present animals and plants. Suppose we first examine the Rio San Francisco. The basin of this river is entirely isolated.
Are its inhabitants, like its waters, completely distinct from those of other basins
? Are its species peculiar to itself, and not repeated in any other river of the continent? Extraordinary as this result would seem, I nevertheless expect to find it so. The next water-basin we shall have to examine will be that of the Amazons, which connects through the Rio Negro with the Orinoco. It has been frequently repeated
that
the same species of fish exist in the waters of the San Francisco and in those of Guiana and of the Amazons. At all events, our works on fish constantly indicate Brazil and Guiana as the common home of many species; but this observation has never been made with sufficient accuracy.
Fifty years ago the exact locality from which any animal came seemed an unimportant fact in its scientific history, for the bearing of this question on that of origin was not then perceived. To say that any specimen came from South America was quite enough; to specify that it came from Brazil, from the Amazons, the San Francisco, or the La Plata, seemed a marvelous accuracy in the observers. In the museum at Paris, for example, there are many specimens entered as coming from New York or from Para; but all that is absolutely known about them is that they were shipped from those seaports. Nobody knows exactly where they were collected. All this kind of investigation is far too loose for our present object. Our work must be done with much more precision.
Therefore, my young friends who come with me on this expedition, let us be careful that every specimen has a label, recording locality and date. We must try not to mix the fish of different rivers, even though they flow into each other, but to keep our collections
perfectly
distinct. You will easily see the vast importance of thus ascertaining the limitation of species, and the bearing of the result on the great question of origin. [br] The pronoun "that" in Paragraph 4 refers to________.
选项
A、a locality
B、the fact
C、a bearing
D、the question
答案
D
解析
语篇衔接。that指代上文提到的单数名词(复数形式为those),需要回溯前文方可确定。原句为“…for the bearing of this question on that of origin was not then perceived”,that指the question最符合语义逻辑。
转载请注明原文地址:http://tihaiku.com/zcyy/3934954.html
相关试题推荐
SOCIALITYINANIMALS(1)Social
SOCIALITYINANIMALS(1)Social
SOCIALITYINANIMALS(1)Social
SOCIALITYINANIMALS(1)Social
SOCIALITYINANIMALS(1)Social
SOCIALITYINANIMALS(1)Social
SOCIALITYINANIMALS(1)Social
COGNITIVEMAPSINANIMALS(1)A
COGNITIVEMAPSINANIMALS(1)A
COGNITIVEMAPSINANIMALS(1)A
随机试题
Noiseconstitutesarealandpresentdangertopeople’shealth.Dayandnigh
[originaltext]M:ManystudentsarecomplainingaboutProf.Gilmore’slectures.
DoCleanSmellEncourageCleanBehaviorYearsago,socials
辨别蛇头疔成脓与否的简便方法是()A.痛剧而呈搏动性者 B.应指验脓法
我国在世界各地开办孔子学院,向各国人民介绍中国文化。这说明教育文化具有( )。
根据《民法通则》的规定,下列可以从事个人理财业务的主体是()。A.十周岁以上的未
中线的概念是A.平分颅面部为两等分的一条假想线 B.穿过两眼中间的一条假想线
下列关于率的标准误的叙述,错误的是A.样本率的标准差称率的标准误 B.率的标准
银行承兑汇票的承兑银行,应当按照票面金额向出票人收取()的手续费。A:千分之一
治疗感染性休克时,糖皮质激素不能A.阻断α受体的兴奋作用 B.兴奋β受体的血管
最新回复
(
0
)