光合作用

For all their importance,

最重要的是

they're actually the simplest of life forms,

他们实际上是最简单的生命种类

nothing more than bacteria.

不比细菌的细胞多

When you get up close you can see

当你靠近观察

that it's only the outer part that's alive.

就只有外面这一部分是活着的

It's a layer of bacteria that secretes a thin film of slime

这一层细菌分泌一层薄薄的粘液

which builds up layer upon layer.

一层接一层粘合起来

It might not look like it,

它虽然看起来不怎样

but these are the most successful Life forms on the planet.

不过这些是地球上最成功的生命种类

These stromatolites have been around

叠层石诞生至今

for 3,500 million years.

已经三十五亿年了

That's three-quarters of the age of the planet.

相当于地球四分之三的年纪

And yet when they first evolved almost three billion years ago,

同时它们第一次进化是在超过三十亿年前

these simple life forms began one of the most important transformations

这些简单生命类型开始最重要的变形

the planet has ever seen.

地球目睹了这一切

These stromatolites are special

这些叠层石是特别的

because they did something that was quite extraordinary.

因为它们做了非常特别的事情

As they took in the sunlight and photosynthesised,

它们吸收阳光和进行光合作用

they broke down the chemical bonds in water

分解水的化学键

releasing something that would completely change the planet.

生成一些能彻底改变地球的东西

They released oxygen.

它们生成氧气

重点讲解

1、get up

起立；站起来

I got up and walked over to where he was.

我起身走到他那边。

起床

They have to get up early in the morning.

他们大清早就得起床。

穿…服装；打扮；装扮

They knew how to get themselves up in those days.

那时候，他们懂得打扮。

an old tramp got up in a velvet smoking-jacket.

身穿一件天鹅绒吸烟服的老流浪汉

2、build up

（使）积聚；（使）逐渐增加

The regime built up the largest army in Africa.

该政权逐渐建立起一支非洲规模最大的军队。

The collection has been built up over the last seventeen years.

在过去的17年中，收藏的规模不断扩大。

增强…的体质；建立…的信心

Build her up with kindness and a sympathetic ear.

用友善和富有同情心的倾听来重拾她的信心。

Dr. Johnson and I have been trying to build him up physically.

约翰逊医生和我一直试图增强他的体质。

吹捧；抬举

The media will report on it and the tabloids will build it up.

媒体会报道此事，小报则会大肆吹捧。

Historians built him up as the champion of parliament.

历史学家把他誉为议会的捍卫者。

3、evolve

进化；演变

The bright plumage of many male birds has evolved to attract females.

很多雄鸟进化出鲜艳的羽毛是为了吸引雌鸟。

Maize evolved from a wild grass in Mexico.

玉米是从墨西哥的一种野生禾本植物进化而来的。

（使）逐步发展;（使）演化

a tiny airline which eventually evolved into Pakistan International Airlines.

最终发展成巴基斯坦国际航空公司的一家小型航空公司

Popular music evolved from folk songs.

流行音乐从民歌演变而来。