时差N小时 寻找古老的生命

They know by studying the remains¹ of past lifepreserved in rocks, particularly sedimentary rocks.

研究人员在研究岩石特别是沉积岩中保存着的生物遗骸时找到了证据。

These rocks are formed from particles of mudand sand, typically when they settle to the bottom of a body of water.

这些岩石是由泥土和沙砾沉积在水底形成的。

Fossils of organisms withhard body parts don't appear in sedimentary rock older than about 600 million years,

生物体中较硬的身体部分所形成的化石不会出现在6亿年以上的沉积岩中，

but theEarth is estimated to be 4.6 billion years old.

但是地球预计已经有46亿年之久了。

To find the oldest life, paleontologists looked for it in the oldest sedimentary rock they could find.

为了寻找最古老的生命，古生物学者找到了他们可以找到的最古老的沉积岩。

Sedimentary rocks dating back to Earth's earliest days are rare.

这些可以追溯到形成于地球初期的沉积岩是十分罕见的。

Some of the oldest known areabout three and a half billion years old.

目前所知的一些最古老的沉积岩大约有35亿年的历史。

In these very old rocks, paleontologists have found something that looked familiar.

在这些古老的岩石中，古生物学者发现了一些熟悉的东西。

Certaincommunities of microbes can form layered, rock-like mounds² called stromatolites.

某些菌落可以形成一层一层，岩石状的土丘，被叫做叠层石。

Stromatolitesgrow in shallow bodies of water in many places around the world.

世界上有很多地方的浅水区都存在着叠层石。

In the 1980′s paleontologistsfound the remains of ancient stromatolites in 3.5 billion year old sedimentary rocks.

在20世纪80年代的时候，古生物学家在35亿年的沉积岩里发现了古叠层石的遗骸。

Besides stromatolites, possible microscopic³ fossils have been found in rocks up to 3.5 billion yearsold.

除了叠层石外，其他目前在岩石中已经找到的可能的微观化石已经有长达35亿年的历史了。

While the origin of these tiny structures is still intensely debated, many scientists areconvinced that they are the remains of microorganisms.

虽然关于这些微小结构的起源还存在着严重的分歧，但很多科学家已经确认，他们是微生物的残骸。

It appears that by at least 3.5 billion yearsago, the oceans were teeming⁴ with life, and that the land was also colonized⁵ by microbes veryearly in Earth's history.

似乎在地球演变的早期过程中，至少在35亿年以前，海洋里存在着大量生体命，而陆地是微生物的主要栖息地。

1 remains   

n.剩余物，残留物；遗体，遗迹

参考例句：

• He ate the remains of food hungrily.他狼吞虎咽地吃剩余的食物。
• The remains of the meal were fed to the dog.残羹剩饭喂狗了。

2 mounds   

土堆，土丘( mound的名词复数 )； 一大堆

参考例句：

• We had mounds of tasteless rice. 我们有成堆成堆的淡而无味的米饭。
• Ah! and there's the cemetery' - cemetery, he must have meant. 'You see the mounds? 啊，这就是同墓，”——我想他要说的一定是公墓，“看到那些土墩了吗？

3 microscopic   

adj.微小的，细微的，极小的，显微的

参考例句：

• It's impossible to read his microscopic handwriting.不可能看清他那极小的书写字迹。
• A plant's lungs are the microscopic pores in its leaves.植物的肺就是其叶片上微细的气孔。

4 teeming   

adj.丰富的v.充满( teem的现在分词 )；到处都是；（指水、雨等）暴降；倾注

参考例句：

• The rain was teeming down. 大雨倾盆而下。
• the teeming streets of the city 熙熙攘攘的城市街道

5 colonized   

开拓殖民地，移民于殖民地( colonize的过去式和过去分词 )

参考例句：

• The area was colonized by the Vikings. 这一地区曾沦为维京人的殖民地。
• The British and French colonized the Americas. 英国人和法国人共同在美洲建立殖民地。