million years ago

Cretaceous period , 145 million years ago , was the age of the dinosaurs .

白垩纪期间，145百万年前，是恐的年。

Triceratops are classified under the Cretaceous period around 65 to 145 million years ago .

三角龙被归类在大约65到145百万年前的白垩纪。

South America and Africa separated 200 million years ago .

南美洲和非洲于2亿年前分离。

South America separated from Africa 200 million years ago .

2亿年前南美洲和非洲分离。

It has been suggested that mammals took over from dinosaurs 65 million years ago .

有人提出哺乳动物是在6500万年前取代恐龙的。

Scientists believe that man diverged from the apes between 5 and 7 million years ago

科学家们相信人类是在500至700万年前由类人猿分化而来。

Twenty million years ago , Idaho was populated by dense primordial forest .

2,000万年前，爱达荷州到处都是茂密的原始森林。

Twenty million years ago , Idaho was not the arid place it is now . Rather , it was warm and damp , populated by dense primordial forest

2,000万年前，爱达荷州并不像现在这样干旱。相反，那时的爱达荷州温暖潮湿，有大片的原始森林。

Eighty million years ago , dinosaurs ruled the earth .

八千万年前，地球是恐龙的天下。

Thus humans who lived a million years ago , despite their big brains and sharp stone tools , lived in constant fear of meat-eating animals ．

因此，生活在一百万年前的人类虽然有着巨大的大脑和锋利的石器，却一直生活在对肉食动物的恐惧之中。

Some scientists believe that the first plants to appear on Earth over 500 million years ago probably looked purple , not green .

一些科学家认为,5亿年前出现在地球上的第一批植物可能看起来是紫色的,而不是绿色的。

just having a great old time five million years ago .

仅仅拥有一个伟大的五百万年前的旧时光。

The human history starts about three million years ago .

人类历史开始于大约300万年以前。

I used to go there like a million years ago with my family .

我很久以前常跟家人去的

A million years ago , a million years ago .

很久以前的事了。

That was like a million years ago .

这事象已经过了一百万年了。

A million years ago , there were animals here before man came .

一百万年前，在还没有出现人类以前，这里就有动物。

They evolved over 4.4 million years ago among our first ancestors ,

这些大脑系统早在440万年前就从人类最早的祖先中演化而来，

Dinosaurs last lived on Earth about 65 million years ago .

最后一批恐龙生活在距今6500万年的地球上。

Several million years ago , our country was covered by thick forests .

几百万年前，我们的大地被茂密的森林覆盖着。

And you know , five hundred million years ago there would be no fish .

这样的话你就知道，5亿年前就不会有鱼。

This new photo reportedly shows galaxies from 13.2 million years ago .

据说这张新的照片显示132亿年前的星系。

lived 260 million years ago and looked almost nothing like a modern turtle ,

它生活在2.6亿年前，看上去几乎不像现代龟，

The divergence among those three species occurred about 2 ~ 6 million years ago .

金丝猴属的分化大约发生在2～6百万年以前。

They could be left over from a burst of star formation several million years ago .

它们有可能是数百万年前的恒星暴增所残存下来的。

A million years ago , the species began to overrun the earth .

100万年以前，该物种开始大批出现于地球各处。

Specifically : four , eight , and twelve million years ago , respectively .

具体产生分支的时间分别是：四百万、八百万和一千二百万年前。

Then from about 600 to 800 million years ago , multi-celled organisms appear .

然后6亿年到8亿年之前，多细胞生物出现。

To exist some sixty million years ago .

直到一百五十年以前科学家们才知道有恐龙存在。

Various australopithecines existed in South Africa from about three million years ago .

各种不同的南方古猿在三百万年以前就生活在南非。