1.地球的诞生（45亿年前）

2.最初的生物体（35亿年至40亿年前）

3.光合作用（34亿年前）

4.大陆形成（30亿年前）

5.可以呼吸的空气（24亿年前）

6.复杂的细胞（10亿年到20亿年前）

7.交配的起源（12亿年前）

8.大型生物体（10亿年前）

9.冰冻的世界（6.35亿年至8.5亿年前）

10.进化过程中的飞跃（5.35亿年前）

11.离开大海（4.65亿年前）

12.奥陶纪的考验（4.3亿年至4.6亿年前）

13.从鳍到腿（3.75亿年前）

14.蜥蜴（3.2亿年前）

15.超级大陆（3亿年前）

16.二叠纪灭绝（2.52亿年前）

17.有毛的野兽（2.2亿年前）

18.恐龙大发展（2.01亿年前）

19.鸟类的飞行（1.6亿年前）

20.植物的革命（1.3亿年前）

21.第五次大灭绝（6500万年前）

22.住在树上（5500万年至6000万年前）

23.C4光合作用（2500万年至3200万年前）

24.通向人类的道路（700万至1300万年前）

25.会思考的猿（20万年）

4.5b years ago

Earth is born

Birth of a planet

Earth grew from a cloud of dust and rocks surrounding the young Sun. Earth formed when some of these rocks collided. Eventually they were massive enough to attract other rocks with the force of gravity, and vacuumed up all the nearby junk, becoming the Earth. The Moon probably formed soon after, when a planet-sized chunk of rock smashed into the Earth and threw up a huge cloud of debris. This condensed into the Moon.

45亿年前

地球起源

星球的诞生

地球是从围绕年幼的太阳旋转的尘埃和岩石云成长而来的。一些岩石碰撞便形成了地球。最终这些岩石庞大到足以靠引力吸引其他岩石，吸附了附近所有的“垃圾”，从而形成了地球。月球可能是在不久之后形成的。当时一颗行星大小的石块砸到地球，抛起巨大的尘埃云，随后便凝结成月球。

4-3.5b years ago

The origin of life

First organisms

Nobody knows exactly when life began. The oldest confirmed fossils, of single-celled microorganisms, are 3.5 billion years old. Life may have begun a bit earlier than that, but probably not while huge rocks were still raining down on Earth. Life may have begun in warm alkaline vents on the seabed, or in open water, or on land. We don't know, and we don't know what the first organisms were like.

35亿年至40亿年前

生命的起源

最初的生物体

没人确切地知道生命何时开始。最古老的化石是单细胞微生物化石，距今35亿年。生命的发端可能稍早于此，但在巨大的石块雨点般地落到地球上时，地球上也许还没有生命。生命可能出现在温暖而碱性的海床洞口、开阔水域或陆地上。我们不知道。我们也不知道最初的生物体是什么样子。

3.4b years ago

Life harnesses the power of sunlight

Photosynthesis

All life needs energy to survive, and the biggest source of energy for life on Earth is the Sun. Some of the early microorganisms evolved a way to use the energy from sunlight to make sugars out of simpler molecules. This process is called photosynthesis. But unlike green plants today, the first photosynthesising organisms did not release oxygen as a waste product, so there was no oxygen in the air.

34亿年前

生命利用阳光的作用

光合作用

所有生命都需要能量才能生存，而地球上最大的能量来源就是太阳。一些早期的微生物进化出一种利用阳光的能量把简单的分子制成糖的方法。这个过程被称为光合作用。但与今天的绿色植物不同，最初能进行光合作用的生物体并不能释放氧气，所以空气中没有氧气。

3b years ago?

The beginning of plate tectonics

Continents form

Today, Earth's surface is divided into a few dozen plates of rock, one of which sometimes ploughs under another to be destroyed in the planet's molten heart. This process, called plate tectonics, is thought to have begun around 3 billion years ago. Only when plate tectonics had come into operation could the first continent, nicknamed 'Ur', come into being.

30亿年前

板块构造开端

大陆形成

今天，地球表面被分割为几十个岩石板块，有的板块会插入另一板块下方，最终被地球的熔岩核心所熔化。这个过程被称为板块构造，被认为开始于大约30亿年前。只有当板块构造开始进行后，第一块大陆才形成。

2.4b years ago

The Great Oxidation Event

Breathable air

For the first half of Earth's history, there was hardly any oxygen in the air. But then some bacteria began harnessing sunlight to make sugar from carbon dioxide and water, just like green plants today. These microbes pumped out oxygen as a waste product, creating the oxygen-rich atmosphere we have today. But the first oxygen may have caused the entire planet to freeze over into a 'Snowball Earth', by stripping the greenhouse gas methane from the air.

24亿年前

伟大的氧化事件

可以呼吸的空气

在地球前一半的历史中，空气中几乎没有氧气。后来，一些细菌开始利用太阳光，把二氧化碳和水制成糖，正如今天的绿色植物所做的一样。这些微生物把氧气当作废物排出，从而创造了我们今天富含氧气的大气。但最初的氧气可能导致整个地球冰冻，成为一个“雪球”，因为氧气抽走了空气中的温室气体甲烷。

2-1b years ago

Endosymbiosis

Complex cells

The first organisms were simple cells like modern bacteria, but some of them became much more internally complex. These 'eukaryotes' developed lots of specialised equipment within their cells. They also had a new source of energy: sausage-shaped objects called mitochondria that were once free-living bacteria, but which were absorbed in a process called endosymbiosis. Every animal and plant you've ever seen is a eukaryote.

10亿年到20亿年前

内共生现象

复杂的细胞

最初的生物体和现代细菌一样是单细胞的，但有些生物体的内部结构变得更加复杂。这些“真核生物”在细胞内部进化出了许多专门“工具”。它们也有了新的能量来源：被称为线粒体的东西。线粒体曾经是自由生活的细菌，但被吸收进一个称为内共生的过程之中。每一种动物和植物都是真核生物。

1.2b years ago?

The first sex

Origin of mating

Between 1.8 billion and 800 million years ago, the fossil record looks fairly dull – so much so that the period is called the 'Boring Billion'. But behind the scenes plenty was happening. For one thing sex may have evolved for the first time. It's not clear why, or when, some organisms stopped simply dividing in two and started the messy business of sex. But it was definitely going on 1.2 billion years ago: there are fossils of red algae from that time that were clearly forming specialised sex cells such as spores.

12亿年前

第一次性别

交配的起源

18亿年前至8亿年前的化石记录显得颇为沉闷，但幕后有很多事发生。其中之一就是第一次有了性别。目前人们还不清楚为什么或何时，有的生物停止一分为二的过程而开始有性别之分。但在12亿年前，这件事的确发生了：那时的红藻化石明显形成了专门的生殖细胞，如孢子。

1b years ago?

Multicellular life

Big organisms

For the first time, life was not just made up of single cells. Now cells were teaming up to form larger organisms with things like mouths, limbs and sense organs. It's hard to say when this happened: there are fossils of large organisms dating back 2.1 billion years, but these may simply have been colonies of bacteria. Different groups of organisms probably evolved multicellularity independently, with plants managing it before animals.

10亿年前

多细胞生物

大型生物体

生命第一次不再只是由单细胞组成。现在，细胞合起来形成了更大的生物体，有了嘴、四肢和感觉器官。很难说这发生在什么时候：大型生物体的化石距今有21亿年，但那可能只是细菌菌落。不同类的生物可能单独进化成多细胞生物体，而植物要早于动物。

850-635m years ago

Snowball Earth

A frozen world

Earth froze over again, twice, in the space of 200 million years. The ice may well have stretched all the way from the poles to the equator. This second Snowball period may have triggered the evolution of the first complex animals. The first complex organisms, weird tube- and frond-shaped things called the Ediacarans, appeared soon after.

6.35亿年至8.5亿年前

成为雪球的地球

冰冻的世界

地球又一次冰冻了，一冻就是2亿年。冰很可能从两极一直冻到赤道。第二次冰冻时期可能触发了第一批复杂动物的进化。不久后，地球上出现了第一批复杂的生物体埃迪卡拉动物群。

535m years ago

The Cambrian Explosion

Evolutionary leaps

Soon after animals evolved, evolution went through two major growth spurts. In the Cambrian Explosion, it seems almost every group of modern animals appeared within tens of millions of years. This apparent 'explosion' may be partly down to better fossilisation, as many animals now had hard shells. Then 489 million years ago, each animal group expanded in the Great Ordovician Biodiversification Event.

5.35亿年前

寒武纪生命大爆发

进化过程中的飞跃

不久，动物发生了进化，进化经历了两次大的飞跃。在寒武纪生命大爆发时期，几乎每一类现代动物在这几千万年间都出现了。这种表面上的“大爆发”可能是因为化石成形得更好一些，因为很多动物都有了坚硬的外壳。后来在4.89亿年前的奥陶纪早期，每一类动物都有了发展。

465m years ago

Plants colonise the land

Out of the sea

Some animals ventured onto land as far back as 500 million years ago, but they only visited briefly – perhaps to lay eggs in a place without predators. Plants were the first to take up permanent residence on land. The first land plants were relatives of green algae, but they rapidly diversified.

4.65亿年前

植物统治陆地

离开大海

有些动物早在5亿年前就曾冒险登上陆地，但它们逗留的时间很短，也许只是为了在一个没有天敌的地方产卵。植物首先在陆地上永久居留。第一种陆生植物是绿藻的亲戚，不过它们迅速开始多样化。

460-430m years ago

The first mass extinction

Ordovician ordeal

The Ordovician period was a time when life flourished. But towards its end, the world cooled dramatically and ice sheets spread from the poles. The ensuing ice age is called the Andean-Saharan, because the evidence of it comes from the Andes mountains and the Sahara desert. The deep freeze led to the second-worst mass extinction on record, the Ordovician-Silurian. Most life was still confined to the sea, and 85% of marine species were wiped out. In the aftermath, fish became much more common.

4.3亿年至4.6亿年前

每一次生命大灭绝

奥陶纪的考验

奥陶纪是生命大发展的时期。但在奥陶纪末期，世界急剧变冷，冰盖从两极铺开。随后的冰河时代被称为安第斯-撒哈拉冰河期，因为其证据来自于安第斯山脉和撒哈拉大沙漠。温度的迅速降低导致了有史以来第二大物种灭绝事件—奥陶纪-志留纪事件。大多数生命仍然在海里，85%的海洋物种灭绝。此后，鱼更加普遍。

375m years ago

Fish that walk on land

From fins to legs

With plants well-established on land, the next step was for animals to move out of the water. Insects were among the first, around 400 million years ago. But they were followed soon after by big, backboned animals such as Tiktaalik, a fish that looked a bit like a salamander. Fish like Tiktaalik would eventually evolve four limbs, and give rise to amphibians, reptiles and mammals. It may be a good thing it left the water when it did, as soon afterwards the Late Devonian Extinction wiped out many marine animals, including some terrifying-looking armoured fish.

3.75亿年前

行走在陆地上的鱼

鳍到腿

植物稳稳地占据陆地后，下一步就是动物离开水。昆虫是最早离开水的，大约在4亿年前。不久后就是有脊椎的大型鱼类。鱼最终进化出四肢，随后出现了两栖动物、爬行动物和哺乳动物。离开水可能是件好事，因为在不久后的晚泥盆世，许多海洋生物灭绝了。

320m years ago

Dawn of the reptiles

Reptilian evolution

When the first reptiles appeared, Earth was in the middle of a long cold snap called the Late Paleozoic Ice Age. Reptiles evolved from newt-like amphibians. Unlike their ancestors they had tough, scaly skin and laid eggs with hard shells that did not have to be left in water. Thanks to these advantages, they quickly became the dominant land animals. The reptile-like Dimetrodon reached 4.5m long – but despite what you may have heard, it was not a dinosaur.

3.2亿年前

爬行动物的出现

爬行动物的演进

第一种爬行动物出现时，地球还处在晚古生代冰河期。爬行动物是从类似蝾螈的两栖动物进化而来的。与它们的祖先不同，爬行动物有坚硬、鳞片状的皮肤，所产的卵有硬壳，所以不必产在水中。由于有了这些优势，它们很快成为占主导地位的陆生动物。

300m years ago

Pangaea

Supercontinent

For the last time, all Earth's continents came together to form one giant supercontinent. Known as Pangaea, it was surrounded by a world-spanning ocean called Panthalassa. It lasted until 175 million years ago, when it began to tear itself apart over tens of millions of years. Its shattered remnants became the familiar modern continents.

3亿年前

原始大陆

超级大陆

这是最后一次地球上的所有陆地连成一体，形成一个巨大的超级大陆。这个被称为“泛大陆”的超级大陆周围是横跨整个世界的大洋，称为“泛大洋”。它一直持续到1.75亿年前，在后来的几千万年间开始分裂。分裂后的部分便形成了今天我们熟悉的现代大洲。

252m years ago

The Great Dying

Permian extinction

Just as the reptiles were flourishing, life on Earth faced perhaps its greatest challenge. The Permian extinction was the worst mass extinction in the planet's history, obliterating up to 96% of marine species and similar numbers of land animals. We don't know for sure what caused it, but massive volcanic eruptions – creating what is now the Siberian Traps – may have been to blame. In the aftermath, the first dinosaurs evolved.

252m years ago

最严重的物种大灭绝

二叠纪灭绝

就在爬行动物大行其道时，地球上的生命遭遇了可能是最大的一次挑战。二叠纪灭绝是地球历史上最严重的物种大灭绝，消灭了96%的海洋物种和差不多一样多的陆地动物。我们不确定它是什么原因引起的，但大规模火山喷发可能是罪魁祸首。此后，第一种恐龙出现了。

220m years ago

The first mammals

Hairy beasts

At the same time that the dinosaurs were spreading and diversifying, the first mammals evolved. Their ancestors were reptiles called cynodonts, whose faces looked a little like those of dogs and may have had fur or whiskers. Early mammals such as Morganucodon were small and shrew-like, and probably only active at night. This may have spurred them to evolve warm-bloodedness: the ability to keep their body temperature constant.

2.2亿年前

第一种哺乳动物

有毛的野兽

就在恐龙发展壮大之时，第一种哺乳动物也出现了。其祖先是一种爬行动物。早期的哺乳动物都很小，像地鼠，可能只在夜间活动。这可能促使它们进化出保持恒温的能力。

201m years ago

The Triassic extinction

Dinosaurs unleashed

The dinosaurs were flourishing on land, and in the sea giant reptiles called ichthyosaurs had become the top predators. Then another disaster struck. We’re not sure what caused the Triassic extinction, but it killed off around 80% of species. In the aftermath, the dinosaurs became the dominant land animals and eventually reached titanic sizes. The biggest species whose mass is accurately known, Dreadnoughtus schrani, weighed about 59 tonnes.

2.01亿年前

三叠纪物种灭绝

恐龙大发展

没有人知道是什么原因造成了三叠纪物种灭绝，但它导致约80%的物种消失。此后，恐龙成为占主导地位的陆生动物，最终发展为巨型生物。

160m years ago

The first birds

Feathered flight

Birds evolved from feathered dinosaurs – modern birds are essentially Velociraptors with beaks instead of snouts and wings instead of arms. The most famous early bird, Archaeopteryx, lived 150 million years ago. But in recent years slightly older fossils, such as Xiaotingia and Aurornis, have been found in China.

1.6亿年前

第一种鸟类

鸟类的飞行

鸟类是从有羽毛的恐龙进化而来的。最著名的早期鸟类始祖鸟生活在1.5亿年前。但近年来，中国发现了更古老的化石，如晓廷龙属和曙光鸟属。

130m years ago

Flowers flower

Plant revolution

This may sound strange, but flowers are a recent invention. There have been land plants for 465 million years, yet there were no flowers for over two-thirds of that time. Flowering plants only appeared in the middle of the dinosaur era. The equally-familiar grasses appeared even more recently. The oldest fossil grasses are just 70 million years old, although grass may have evolved a bit earlier than that.

1.3亿年前

开花植物

植物的革命

这可能听起来很奇怪，但花的出现是最近的事情。陆生植物生存了4.65亿年，但在超过三分之二的时间里是没有花的。开花植物只是在恐龙时代中期才出现的。我们同样熟悉的草的出现时间甚至更晚。最古老的草化石只有7000万年历史。

65m years ago

Death of the dinosaurs

The fifth extinction

Boom, you're extinct. 65 million years ago, a huge chunk of rock from outer space smashed into what is now Mexico. The explosion was devastating, but the longer-term effects were worse. Dust was thrown into the upper atmosphere and blocked out sunlight, and in the ensuing cold and darkness Earth suffered its fifth and last mass extinction. The dinosaurs were the most famous casualties, but pterosaurs and giant marine reptiles were also wiped out.

6500万年前

恐龙灭亡

第五次大灭绝

6500万年前，来自外太空的巨大陨石砸到了现在的墨西哥。爆炸是毁灭性的，但爆炸的长期影响更加恶劣。尘埃被抛入高层大气，阻挡了阳光。在随后的寒冷和黑暗中，地球遭受了第五次物种大灭绝。恐龙灭亡了，翼龙和巨型海洋爬行动物也灭亡了。

60-55m years ago

The first primates evolve

Living in the trees

Almost immediately after the dinosaurs were wiped out, mammals evolved the ability to nourish their young inside their wombs using a placenta, just like modern humans. Soon, some of these early placental mammals evolved into the first primates. They would ultimately give rise to monkeys, apes and humans. But the first ones were small creatures. The oldest known primate skeleton is of a species called Archicebus achilles, which weighed no more than 30 grams. They lived in the hot and humid rainforests of Asia.

5500万年至6000万年前

灵长类演进

住在树上

几乎就在恐龙灭绝时，哺乳动物进化出了像现代人类一样利用胎盘在子宫内养育后代的能力。不久，一些早期的有胎盘哺乳动物进化成第一种灵长类动物，它们最终进化为猴、猿和人。最初的灵长类动物的个子很小，中国发现最古老的灵长类动物（阿喀琉斯基猴）的骨骼还不到30克，他们生活在闷热、潮湿的亚洲热带雨林。

32-25m years ago

Supercharged plants

C4 photosynthesis

Plants have been busily harnessing sunlight to make sugar for hundreds of millions of years – a process called photosynthesis. But fairly recently, some plants have found a better way to do it. C4 photosynthesis is far more efficient than normal photosynthesis, allowing C4 plants to cope with harsh conditions. Today scientists are trying to engineer rice to use C4 photosynthesis, to help feed the growing population.

2500万年至3200万年前

特别有效的植物

C4光合作用

几亿年来，植物一直在利用阳光制造糖—这个过程被称为光合作用。但后来有些植物找到了更好的办法。C4光合作用远比普通的光合作用更高效，从而使得C4植物能应对更苛刻的自然条件。今天的科学家正在尝试用C4光合作用改变大米的基因结构以养活日益增长的人口。

13-7m years ago

The first hominins

The road to humanity

The first apes appeared in Africa around 25 million years ago. Then at some point, the group split into the ancestors of modern humans and the ancestors of modern apes. It's hard to say exactly when, but thanks to modern genetics and a host of fossil discoveries, we have a rough idea. The oldest known hominid was Sahelanthropus tchadensis, which lived about 7 million years ago.

700万年至1300万年前

生存年代最久远的类人猿

向人类的道路

2500万年前，第一种猿类出现在非洲。后来，在某个时候，该物种分成了现代人类的祖先和现代猿的祖先。借助发现的化石和现代的基因技术，已知最古老的原始人是乍得人猿，大约生活在700万年以前。

200,000 years ago

The human race

The thinking ape

Our species, Homo sapiens, is ridiculously young. We have only existed for a fifth of a million years. In that time we have expanded from our African birthplace to reach every continent, and even outer space. Our activities have precipitated the sixth mass extinction and unleashed the fastest episode of climate change in Earth's history. Yet we are also the only species that has ever managed to piece together the history of Earth.

20万年

人类

会思考的猿

我们这个物种—智人—相当年轻。我们只存在了20万年。在这段时间里，我们已从非洲发展到每一个大陆，甚至到了外太空。我们的活动已造成第六次物种大灭绝，催生了地球历史上最快的气候变化过程。但我们人类也是唯一能够将地球的历史连接到一起的物种。

The 25 Biggest Turning Points in Earth's History

reference

地球历史

生命史

生物大灭绝

地球空心说

 The End