Mineral Evolution托福听力原文翻译及问题答案

Mineral Evolution托福听力原文翻译及问题答案

一、Mineral Evolution托福听力原文：

NARRATOR:Listen to part of a lecture in a geology class.

MALE PROFESSOR:Since Earth formed,some four and a half billion years ago,the number of minerals here has increased dramatically,from a few dozen relatively simple minerals early on…to over 4,300 kinds of minerals we can identify today—many of them wonderfully complex.A basic question of geology is how all these new minerals came into being.Well,recent studies have turned to biology to try to explain how this happens.

Now,much of biology is studied through the lens of evolution.And the theory of evolution suggests that,as environments change—and inevitably they do—some organisms will have characteristics that allow them to adapt to those changes successfully…characteristics that help these organisms develop and survive and reproduce.And when environments become more complex—as tends to happen over time—those earlier adaptations,those variations…become the basis of yet other combinations and variations…and lead to ever more diverse and complex forms of life.So from fewer,simpler,and relatively similar forms of life billions of years ago,life on Earth has now become a dazzling array of diversity and complexity.

Well,some geologists now want to apply this concept to explain mineral diversity too.The conditions that minerals are under are not constant.Conditions like temperature or pressure or chemical surroundings—these change—often in cycles,increasing and decreasing slowly over time.And as conditions change,minerals sometimes break down and their atoms recombine into totally new compounds,as part of a process some call mineral evolution.

Now,minerals are not alive,of course,so this is not evolution in quite the same sense you'd have in living organisms.But there do appear to be some parallels.Living organisms not only adapt to their environment but also affect it—change the environment within which other organisms may then develop.Likewise,each new mineral also enriches the chemical environment from which lots of other,even more complex new minerals may be formed in the future.

Beyond these similarities,though,what's really fascinating about mineral evolution is the way minerals apparently coevolve with living organisms.Uh,what do I mean by that?

Well,it's maybe a billion years after Earth’s formation that we first see evidence of life.Of course,early life-forms were primitive—just tiny,single-celled microbes—but over time,they had a profound effect.Huge numbers of these microbes began producing food by photosynthesis,which,of course,also freed up enormous amounts of oxygen.And lots of that oxygen interacted with the atoms of existing minerals,creating rust out of iron,for instance,…reacting with a whole range of different metals to create lots of new minerals.

Now,living organisms rely on minerals.But they not only take in some minerals as nutrients,they also excrete others as waste products...including what we call biominerals—minerals that form with the help of biological life.We can see geologic evidence of biomineral production in what are called stromatolites.

Stromatolites look like wavy layers of sedimentary rock.But they're really fossils—fossils of the waste from microbial mats.Microbial mats are vast colonies of one-celled organisms…that were once the most prevalent form of life on Earth.And the study of stromatolites indicates that these ancient microbial mats interacted with minerals in the environment and left behind new compounds as waste products—biominerals like carbonates,phosphates,and silica.In fact,we’ve grown microbial mats in the laboratory,and,over time,they too have produced some of the same sorts of minerals found in stromatolites.Uh,you don't need to know the details of the process right now—we’re still figuring out just how it works,ourselves.

But you might be interested to know that this concept of mineral evolution is being used in the search for evidence of life on other planets.The thinking is that if certain minerals occur here on Earth as a result of a biological process,and if we also find those same minerals on another planet,…this would suggest that life may have once existed there.

But—just because a particular mineral is found on say,Mars or Venus—uh,we really shouldn't assume that whatever caused it to turn up there…must be the same process that formed that mineral here on Earth.

二、Mineral Evolution托福听力中文翻译：

旁白：听地质学课上的一节课。

男教授：自从地球形成以来，大约在45亿年前，这里的矿物数量急剧增加，从早期的几十种相对简单的矿物…到今天我们可以识别的4300多种矿物，其中许多非常复杂。地质学的一个基本问题是这些新矿物是如何形成的。最近的研究转向生物学试图解释这是如何发生的。

现在，很多生物学都是从进化的角度来研究的。进化论表明，随着环境的变化，不可避免地，一些生物体会具有一些特征，使它们能够成功地适应这些变化……这些特征有助于这些生物体的发展、生存和繁殖。随着时间的推移，当环境变得越来越复杂时，这些早期的适应，这些变化…成为其他组合和变化的基础…并导致更加多样和复杂的生命形式。因此，数十亿年前，地球上的生命从更少、更简单和相对相似的生命形式，现在变成了一系列令人眼花缭乱的多样性和复杂性。

现在，一些地质学家也想用这个概念来解释矿物多样性。矿物所处的条件不是恒定的。温度、压力或化学环境等条件通常会发生周期性变化，随时间缓慢增减。随着条件的变化，矿物有时会分解，它们的原子会重新组合成全新的化合物，这是一些人称之为矿物演化过程的一部分。

当然，矿物是没有生命的，所以这并不是进化，也不是生物体的进化。但似乎有一些相似之处。生物不仅适应环境，而且影响环境-改变其他生物可能在其中发展的环境。同样，每一种新矿物也丰富了化学环境，未来可能会形成许多其他甚至更复杂的新矿物。

尽管如此，除了这些相似之处之外，矿物进化的真正吸引人之处在于矿物显然与生物共同进化的方式。我这是什么意思？

也许是在地球形成10亿年后，我们才第一次看到生命的迹象。当然，早期的生命形式很原始，只是微小的单细胞微生物，但随着时间的推移，它们产生了深远的影响。大量这些微生物开始通过光合作用生产食物，当然，这也释放了大量的氧气。大量的氧与现有矿物的原子相互作用，例如，使铁生锈……与一系列不同的金属反应，产生大量新的矿物。

现在，生物依靠矿物质。但它们不仅吸收一些矿物质作为营养物质，还将其他矿物质作为废物排出……包括我们称之为生物矿物质的矿物质，这些矿物质是在生物生命的帮助下形成的。我们可以在所谓的叠层石中看到生物矿物产生的地质证据。

叠层石看起来像沉积岩的波浪层。但它们实际上是化石，是微生物垫产生的废物化石。微生物席是单细胞有机体的巨大聚落…曾经是地球上最普遍的生命形式。对叠层石的研究表明，这些古老的微生物席与环境中的矿物相互作用，留下了新的化合物，如碳酸盐、磷酸盐和二氧化硅等生物矿物废物。事实上，我们已经在实验室里种植了微生物垫，随着时间的推移，它们也产生了一些在叠层石中发现的相同种类的矿物质。呃，你现在不需要知道这个过程的细节，我们自己还在弄清楚它是如何工作的。

但你可能有兴趣知道，矿物演化的概念正被用于寻找其他行星上生命的证据。我们的想法是，如果地球上的某些矿物是生物过程的结果，如果我们在另一个星球上也发现了这些矿物，这将表明那里可能曾经存在过生命。

但是，仅仅因为在火星或金星上发现了一种特殊的矿物，我们真的不应该假设，无论是什么原因导致它出现在那里……一定是地球上形成这种矿物的同一过程。

三、Mineral Evolution托福听力问题：

Q1:1.What is the main purpose of the lecture?

A.To explain how geologists identified the minerals present during Earth's formation.

B.To explain why living organisms require certain minerals to survive.

C.To explain the differences between simple and compound minerals.

D.To explain a recent theory about mineral formation.

Q2:2.What point does the professor make about the minerals present during Earth's formation?

A.They were comparatively few of them.

B.They were more complex than minerals formed on other planets.

C.Most were not affected by temperature and pressure changes on early Earth.

D.Some of them are no longer being formed naturally on Earth.

Q3:3.What similarities does the professor point out between minerals and living organisms?[Click on 2 answers.]

A.Both first appeared on Earth at approximately the same time.

B.They both can be formed only in the presence of oxygen.

C.They both have become more diverse and complex over time.

D.Not only are they both shaped by their environment,but both also affect it.

Q4:4.What are stromatolites?

A.Fossils remains of microbial mats.

B.Layered deposits of iron-based minerals.

C.Layers of rock that indicate changes in Earth's pressure and temperature.

D.Rock formations created when oxygen interacts with certain metals.

Q5:5.Why does the professor talk about microbial mats?

A.To explain why organisms tend to colonize near certain minerals.

B.To describe how minerals can be created by living organisms.

C.To illustrate the effects of geological processes on living organisms.

D.To emphasize that evolving life depended on the presence of oxygen.

Q6:6.What does the professor think about using evidence of minerals on another planet to determine whether life has existed there?

A.He believes it is the most promising way to search for life on another planet.

B.He doubts that complex minerals will ever be found on another planet.

C.He is cautious about assuming that certain minerals indicate the presence of life.

D.He is surprised that the technique was not suggested until recently.

四、Mineral Evolution托福听力答案：

A1:正确答案：D

A2:正确答案：A

A3:正确答案：CD

A4:正确答案：A

A5:正确答案：B

A6:正确答案：C