Despite the basic biological, chemical,

书海库2020-05-20  21

问题 Despite the basic biological, chemical, and physical similarities found in all living things, a diversity of life exists not only among and between species but also within every natural population. The phenomenon of diversity has had a long history of study because so many of the variations that exist in nature are visible to the eye.  1) It has been suggested that sexual reproduction became the dominant type of reproduction among organisms because of its inherent advantage of variability, which is the mechanism that enables a species to adjust to changing conditions.New variations are potentially present in genetic differences, but how preponderant a variation becomes in a gene pool depends upon the number of offspring the mutants or variants produce (differential reproduction). 2)It is possible for a genetic novelty (new variation) to spread in time to all members of a population, especially if the novelty enhances the population’s chances for survival in the environment in which it exists.Thus, when a species is introduced into a new habitat, it either adapts to the change by natural selection or by some other evolutionary mechanism or else it eventually dies off. Because each new habitat means new adaptations, habitat changes have been responsible for the millions of different kinds of species and for the heterogeneity within each species.  The total number of animal and plant species is estimated at between 2,000,000 and 4,500,000; authoritative estimates of the number of extinct species range from 15,000,000 up to 16,000,000,000. 3)Although the use of classification as a means of producing some kind of order out of this staggering number of different types of organisms appears as early as the book of Genesis—with references to cattle, beasts, fowl, creeping things, trees, etc.—the first scientific attempt at classification is attributed to the Greek philosopher Aristotle, who tried to establish a system that would indicate the relationship of all things to each other.He arranged everything along a scale, or “ladder of nature”, with nonliving things at the bottom; plants were placed below animals, and man was at the top. 4)Other schemes that have been used for grouping species include large anatomical similarities, such as wings or fins, which indicate a natural relationship, and also similarities in reproductive structures.  5)At the present time taxonomy is based on two major assumptions: one is that similar body construction can be used as a criterion for a classification grouping; the other is that, in addition to structural similarities, evolutionary and molecular relationships between organisms can be used as a means for determining classification.

选项

答案

解析(1)有人曾经提出:有性繁殖在有机生命体的繁殖方式中占支配地位,其原因在于有性繁殖所固有的变异性方面的优势。变异性是一种机制,能使物种自我调节以适应条件的变化。  【解析】该句需要注意的是It has been suggested...不能直接翻译成“它被建议…”,it指代的该句中that之后的内容,此处it只是起到形式主语的作用,因此应根据汉语多主动句的特点将其译为:有人曾经提出…。(2)某种遗传变异(新变异)及时扩散到一个生物群体的所有成员,这是可能的。尤其当这种变异能提高该群体在其生存环境中的存活机会时,可能性更大。  【解析】本句需要注意的是对It is possible...的翻译,由于真正的主语是possible之后的内容,因此翻译时应译为:…是由可能的。此外,enhance的宾语为chances(机会),因此应取其“提高”的意思。(3)虽然早在《物种起源》那本书中就使用分类方法把为数众多的不同种类的生物排列出了一个次序,书中提到的生物包括:家养牲畜、野兽、禽类、爬行动物、树木等。不过,真正从科学上首次尝试对物种分类还应归于希腊哲学家亚里士多德。他曾试图建立一个体系,来表明世界万物彼此之间的关系。  【解析】本句中破折号之间的内容为解释说明,翻译时可将其独立成句,并添加主语,即:书中提到的生物包括:家养牲畜、野兽、禽类、爬行动物、树木等。(4)曾经用来进行物种分类的其他方法还有:根据解剖结构上存在的重大相似性分类,比如翅膀或鳍,这种相似性显示的是自然属性的关系;还可以根据繁殖系统结构的相似性分类。  【解析】anatomical意为“结构上的,解剖的”,fin指“鱼鳍,鳍状物”,该句中which引导的定语从句是对anatomical similarities的修饰。(5)目前,生物分类学基于两大思路:一个是可以用生物体结构的相似性作为物种分类的依据;另一个是,除了结构的相似性以外,还可以把生物在进化以及分子方面的关联作为决定分类的依据。  【解析】taxonomy意为“(生物)分类学”,注意该句中被动形式“taxonomy is based on”与汉语主动形式“生物分类学基于…”之间的转换。
转载请注明原文地址:https://ti.zuoweng.com/ti/yQVpKKKQ