Galapagos, magical animals change!

Galapagos

A world away

But the islands are extremely beautiful

This is located in the Eastern Pacific

Nearly 1,000 kilometers from South America

The island area is only 8,000 square kilometers

Less than a quarter of Hainan Island

There are countless unforgettable wonders of life

(The Galapagos Islands belong to Ecuador, and the name comes from the Spanish Islas Galápagos, also known as the Colon Islands. Map by Zheng Yi @ Planet Research Institute)

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This is a tropical area.

But the penguins are swimming happily in the sea

(Swimming Galapagos penguins, also known as Galapagos penguins. The cold current has created a cool environment here. Image source: @Visual China)

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The birds on the coast are unique

Blue-footed booby showing off its big blue feet

(Blue-footed boobies on the Galapagos Islands, image source: Visual China)

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The mountains are full of life

A rare pink iguana looking up at the sky

(The Galapagos pink land iguana is one of the rarest reptiles in the world, with an estimated population of only 200. Image source: Visual China)

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Wild animals near towns are not afraid of people

Sea lions and tourists share a beach

(Please watch in horizontal mode. A photographer is taking a close-up photo of a sea lion, which is still sleeping soundly without paying any attention to the people around. Image source: Visual China)

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This is also a holy place in the history of science

When Darwin first arrived on the island at the age of 26

He wouldn't think

This will inspire him to propose the "Theory of Evolution"

And became his "source of all inspiration in life"

(The Beagle, the research vessel Darwin was on; Darwin expounded the "theory of evolution", also known as "evolution", in "The Origin of Species" published in 1858. Map by Liu Zhipeng @ Planetary Research Institute)

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On this archipelago

Humans are lucky enough to witness the evolution of all things.

Everything is changing at an accelerated pace

To adapt to the changing world

The only eternity here

There is no eternity

(Please watch in horizontal mode to see the colorful Galapagos creatures, among which the Galapagos tortoise is composed of more than a dozen closely related species; map by Zhang Qiyue & Zheng Yi @ Planet Research Institute)

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To explore the source of all these changes

We need to go back 46 years first

Dive into the sea with the famous submersible Alvin

01

Desert Island Newborn

In the deep sea near the Galapagos

Endless coldness and darkness fill this place

(In the past, people believed that there was no sunlight in the deep sea, and plants could not photosynthesize. Except for a few large marine animal remains that sank into the deep sea, no ecosystem could be built. This is not the Galapagos, just for illustration, picture source @NOAA)

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When diving to a depth of more than 1,600 meters

The sea water suddenly became a little warm

When the depth reaches more than 2000 meters

You will see chimneys more than ten meters high rising from the ground.

They emit hot "black smoke"

The surrounding area is full of vitality

(A vibrant submarine hydrothermal ecosystem. The following pictures are submarine chimneys, giant tube worms, giant mussels and blind shrimps with degraded vision. Image source: @Wikimedia Commons)

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The secret lies deep in the earth

Seawater seeps into cracks between rocks

After being heated by magma, it dissolves minerals and erupts

Some microbes use the sprayed chemicals to make nutrients

Other organisms feed on microorganisms

Thus, around the underwater chimney where there is no sunlight

Forming a unique ecosystem

Subsea hydrothermal systems

(Schematic diagram of the submarine hydrothermal ecosystem. Unlike plants that rely on sunlight for photosynthesis, the microorganisms here can directly use inorganic substances such as sulfide to survive. They are called chemoautotrophic microorganisms. Map by Liu Zhipeng @ Planet Research Institute)

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This is the first time humans have discovered an ecosystem that does not rely on sunlight

Since Darwin's theory of evolution

The Galapagos rewrites scientific history once again

But Dadi's ambitions go far beyond this.

The magma is already stirring

It wants to break out of the sea

Create greater miracles

Here is near

Pacific Ocean, Cocos, Nazca

The junction of three major plates

Various geological activities never stop

(Map of the Galapagos Plate. For ease of viewing, the map is in the west at the top and east at the bottom. Map by Zheng Yi @ Planetary Research Institute)

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Beneath the Nazca Plate

There is a hidden crater

Lava from deep in the mantle gushes out from here from time to time.

Gradually solidified in seawater

Eventually forming tall underwater mountains

(Sketch of the process of the formation of islands by submarine volcanic eruptions. The submarine volcano is still active. Map by Liu Zhipeng @ Planetary Research Institute)

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As the Nazca Plate continues to drift southeast

Undersea mountains formed one after another

The Galapagos

It is the small hills that emerge from the sea level.

(Please watch in horizontal mode, the crater of the Galapagos, photographer @徐征泽)

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On the newborn island

The land formed by the solidified lava is dark.

Seemingly lifeless

But the wind brings hope

The Galapagos is located at the intersection of two trade wind belts.

Plant seeds and small animals such as insects can travel on the wind

Plants such as cacti and mosses

These are the earliest species to settle here.

They accelerate the soilification of rocks

Let other lives find a home

(Lava cactus as a pioneer species, picture source: Visual China)

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This is far from the mainland

But it does not prevent birds from flying here

Their feces are excellent fertilizer.

(A large amount of white feces from blue-footed boobies covers the rocks. Image source: @Visual China)

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The soil has nutrients

More seeds begin to take root and sprout

The vegetation is gradually becoming denser

High on the island

There are even forests

The protagonist of these forests is the dandelion's relative, the "tree daisy"

As a plant of the Asteraceae family

It can grow into a tree more than ten meters high.

(The Galapagos tree chrysanthemum forest; the tree chrysanthemum is a plant of the genus Scalesia in the Asteraceae family that is unique to the Galapagos. Asteraceae plants are generally low herbs, while the tree chrysanthemum is a shrub or tree. Image source: @Visual China)

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With only a few plants and small animals carried by the wind

This is still a barren land.

But the land didn't stop there.

But once again with the power of the ocean

Burst out more vigorous vitality

02

Life Convergence

West of the Galapagos

On the island of New Guinea, more than 10,000 kilometers away

A heavy rain washed nutrients from the soil into the river.

Then poured into the sea

(The tropical rainforests and rivers of New Guinea Island will have a wonderful connection with the Galapagos. Image source: @Visual China)

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But this long journey has just begun

A cold current from the deep sea will carry them thousands of miles away.

Until it hit the Galapagos seabed's tall mountains

Nutrients up

Nourishes this sea

(The vibrant Galapagos coral reefs, image source: @Visual China)

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This cold current is called the Cromwell Current.

But it's not the only one that came from afar

Many ocean currents converge in the Galapagos

(Please watch in horizontal mode, the convergence of the Galapagos Ocean Currents, by Zheng Yi @ Planetary Research Institute)

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On the west coast of South America

Strong winds blow away the surface water

Causes cold water from deep sea to rise to the surface

Then send nutrients to the Galapagos

This is the famous Peruvian cold current.

(After the loss of seawater in one place, the ocean current formed by the replenishment of seawater from another place is called a compensation current. The Peruvian cold current is a compensation current. In addition to the lower layer of seawater, it is also partially replenished by Antarctic seawater. Map by Liu Zhipeng @Planetary Research Institute)

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Two cold currents brought coolness and nutrition

The only penguin colony on the equator was born

(Behind the Galapagos penguin is a typical tropical plant cactus. Such natural landscape can only be seen in Galapagos. Image source: Visual China)

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In addition to the main cold current, there is also the help of warm current

The intersection of cold and warm allows nutrients to be more fully diffused

Marine life is also thriving

As Darwin said

“The ocean is a bit crowded here”

(The Galapagos Ocean is one of the most biologically dense seas in the world, image source: @Visual China)

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This is an important habitat for whales.

Huge humpback whales and top predator killer whales

We met on this narrow road

(Killer whales forage in the waters between Fernandina Island and Isabela Island, which was an important whaling site in the 19th century. Image source: Visual China)

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Groups of sharks prepare to enjoy a feast

Hammerhead sharks march like an army

(A large group of hammerhead sharks are foraging, picture source: @Visual China)

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In the offshore

A sea turtle is swimming leisurely towards a school of fish

(Green turtles freely shuttle among dense schools of fish, picture source: Visual China)

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Sea lions lying in the sea basking in the sun

As if dancing with the light

(The Kahai Sea lion is leisurely in the water, picture source: Visual China)

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Even land creatures take advantage of ocean currents

Coming from afar

The giant tortoise is native to South America

Maybe it fell into the sea by accident.

Floating on the sea, drifting thousands of miles to this point

(One theory holds that the Galapagos tortoise originated from the South American continent. Experiments have shown that tortoises can survive for several weeks without food or water, which is enough to support them to drift to the Galapagos. Image source: @Visual China)

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And a piece of wood fell into the sea

Or maybe it's the boat that the iguanas take to get here.

(The Galapagos marine iguana is the only iguana in the world that can go into the sea. Image source: @Visual China)

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Even a small branch floating on the sea

There might be a few insects hiding there.

(The only bees on the Galapagos Islands may have arrived here in this way, image source @Visual China)

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The rich fish resources brought by ocean currents

It also attracts many birds to make their home here.

(Brown Pelican: Feast, here I come! Image source: @图虫创意)

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Blue-footed boobies wear bright blue boots

Hoping to be favored by the opposite sex

(The blue color of the blue-footed booby's feet comes from the carotenoids in their food. The bluer the blue, the better the nutrition, and the more advantages it has when courting a mate. Photographer @徐征泽)

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The frigate bird has a large, bright red throat pouch.

High profile display of affection to females

(Two frigatebirds are competing for the attention of a female. The male frigatebird's huge throat pouch is very conspicuous and is used to attract the opposite sex. Image source: @Visual China)

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The Caribbean Albatross prefers the tropics

Are actively pursuing a future partner

(Courtship dance of the Caribbean Albatross; most species of albatrosses live in cool waters at high latitudes, with only a few distributed in the tropics, image source @Visual China)

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Cormorants with degenerated wings cannot fly

But he is very agile in the water

(The wings of the weak-winged cormorant have degenerated, and they are better at swimming and fishing. Image source: @Visual China)

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Other species have also learned to find alternative ways

For example, red stone crabs will "work" for marine iguanas

Earn some snacks

(Red stone crabs are cleaning the surface of marine iguanas and preying on parasites. This type of crab likes to walk straight. Image source: @Visual China)

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Nourished by ocean currents

These islands have come alive

But they are never stable

Change is the eternal theme here

Life can only continue to adapt

03

Survival of the Fittest

1970s

A massive drought hit

Daphne Island in the Galapagos

Large areas of plants died

(Please watch in horizontal mode, overlooking the Great Daphne Island from the air, where many species of Darwin's finches live. Image source: @Visual China)

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To get more food

Part of the Chinese ground finch selection to broaden the diet

They originally fed on small soft seeds.

Started eating the seeds of another plant

These seeds are larger, harder and more spiny.

Only the middle ground finch, with its wider beak, can peck it open.

They also have a greater chance of survival

(Galapagos Ground Finches, image source: Visual China)

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After this food crisis

The beaks of the next generation of ground finches became noticeably larger and thicker

Even after several years, the vegetation on the island has recovered.

The beak of the middle ground finch has not returned to its original state.

This is the first time humans have witnessed evolution driven by natural selection

But the story isn't over yet

A group of great ground finches from the outer islands

First of all, I broke the peace here

(The Galapagos ground finches are larger than the medium ground finches on the island. Image source: Visual China)

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They also like the large seeds.

The beak is enlarged compared to the middle ground finch.

The beak of the ground finch is thicker

Seeing that the competition is not

Some middle finches are gradually eating small seeds again.

Their beaks are also becoming smaller.

More than 20 years later

Another severe drought is coming

Food shortages

Intensified competition between the middle ground finch and the great ground finch

(The arid land of the Galapagos is for illustration only, image source: @Visual China)

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This time

Fate has not favored the large-beaked middle ground finch

They lose out to the great ground finches in the food competition.

Finally, in the middle ground finch population

The small-beaked individual emerged as the winner

(The Galapagos is like the sea fog in the rainy season, which makes the creatures puzzled. Image source: Visual China)

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Such an evolutionary story

It has been performed countless times in the Galapagos

There are more than a dozen species of Darwin's finches, including the middle and great ground finches.

Most of them have similar evolutionary history

Two to three million years ago

Ancestors of Darwin's finches

Visited the Galapagos Islands

Different islands were formed at different times

Environments vary widely

Some islands have just been formed and are barren and desolate.

Some islands have been formed for a long time and are lush and green.

(Galapagos islands with dense vegetation, image source @Visual China)

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To adapt to the unique habitats of different islands

Birds start their own evolutionary journey

(Darwin's finches eat different foods, and their beaks are also different. Photographer @徐征泽)

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Just as people look different

The ancestors of Darwin's finches will also appear

Different beak shapes, large or small

They come from natural variation in genes

This variation is random.

It's just that some mutations have an advantage in the competition for survival.

are more likely to pass on the gene.

The so-called "survival of the fittest"

As the genetic differences between populations grow

New species are formed

(Diagram comparing the beak shape and diet of 14 species of Darwin's finches, drawn by Zhang Qiyue @ Planet Research Institute)

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Galapagos: the evolutionary arena

Of course, it's not just Darwin's finches

Due to the differences in vegetation in different regions

Some tortoises can nibble on the grass on the ground just by sticking their heads out.

Some have to look up to eat the cacti high up in the sky

As a result, different shapes of turtle shells evolved.

Eventually, more than a dozen different species were formed.

(When Darwin was investigating, local officials said they could tell which island a tortoise came from just by looking at its shell, which greatly inspired Darwin. Map by Zhang Qiyue @ Planet Research Institute)

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There are also iguana ancestors who accidentally drifted here

They originally fed on forest plants.

But the barren island is desolate

The seabed near the shore is lush and green.

So the marine iguana evolved to be able to go into the sea to find food

(Marine iguanas eating seaweed, they are endemic to the Galapagos and the only iguanas that can go into the sea. Image source: @Visual China)

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The rich island environment of the Galapagos

Providing a different stage for evolution

Separated by the ocean and mountains

Organisms on each island evolved independently

(Oceans and mountains block the genetic exchange between different groups, and the differences between groups are getting bigger and bigger. Image source: Visual China)

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At the same time, because the Galapagos is far away from the mainland

Large carnivores could not drift from the mainland.

Animal populations without natural enemies can thrive rapidly

And accumulate more mutations

Promote the formation of new species

(The lack of natural enemies is also an important reason why animals on the Galapagos Islands are not afraid of humans, photographer @高承)

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But they can't rest on their laurels.

The Galapagos environment is changing rapidly

Like a moody boy

Some years

Abnormal atmospheric activity will weaken the cold wave

Making the Galapagos extremely hot

This phenomenon has a more familiar name

El Nino

Facing food shortages caused by heat waves

Marine iguanas die in large numbers on the island

But they soon evolved a countermeasure

Reduce your frame by up to 20% in just a few months

To reduce energy consumption

(In proportion, this is equivalent to a person 1.8 meters tall shrinking to more than 1.4 meters tall, photographer @高承)

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Under the influence of various factors

Evolution seems to have fast-forwarded here.

In just over thirty years

Humanity has witnessed the birth of a new species

(This new species of Darwin's finch is nicknamed "Big Bird" by scholars, picture source @Texas A&M University)

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From the isolated island

The wind and the sea brought in waves of immigrants

Then evolved into colorful life

Today's Galapagos is already very exciting

56 bird species

25 species of reptiles

2900 species of marine life and more

They are all showing the charm of evolution

(The colorful and changeable Galapagos, photographer @高承)

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But this drama of evolution has not ended yet

From life to the island itself

Challenges and changes never stop

04

Only change is eternal

Galapagos Islands

Means "Turtle Island" in Spanish

The name comes from the island's most iconic species.

Tortoise

June 24, 2012

A 100-year-old tortoise died this morning.

Never woke up again

This is the most famous Galapagos tortoise.

"Lonely George"

(Lonely George a few days before his death, image source @Wikimedia Commons)

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Since humans arrived on the island

The docile tortoise became the "canned meat" of the sailors.

The goats and rats on the ship also escaped to the island

Start breeding crazily

Goats nibbling vegetation

Rats eating turtle eggs

As a result, some of the island's tortoises became extinct.

Lonely George

This is the last of the Pinta Island tortoises.

Its death heralds the extinction of a species

(“Where are my companions?”, image source @Wikimedia Commons)

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The fate of other Galapagos species

Still full of uncertainty

To avoid the tragedy from happening again

People clear the island of alien species

The United Nations also included this place in the first batch of World Natural Heritage

(Galapagos Port, the arrival of humans has had a profound impact on the islands, image source @Visual China)

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It is not only the continuation of species that is facing challenges

The same is true for the islands themselves

May 17, 2021

One of the most famous landmarks in the Galapagos

Darwin Arch Bridge collapses

This is a world-renowned diving spot.

Now only the waves remain

(Darwin Arch before collapse, image source: Visual China)

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These molten rocks are struggling to break out of the sea from underground

But it is hard to escape the wear and tear of time

(A pebble beach on the Galapagos coast; in 1992, people discovered pebbles on the seabed of the Galapagos that were older than all the current islands. They are likely to belong to sunken islands. Image source @Wikimedia Commons)

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But this doesn't mean the end

Before the island sank

Some species have already expanded to other places

And evolved new species

And new islands are still waiting to be discovered on the seabed.

(Research shows that the ancestors of the Galapagos lava lizard may have come from a sunken island, photographer @徐征泽)

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On the 4.6 billion-year-old Earth

The 4-million-year-old Galapagos looks remarkably young

It's still growing

Will also experience the trials of wind and rain

It will also create a wonderful evolution story

There is no permanent protagonist here.

Only eternal change

This article was created by

Written by : Lin Xuanwen

Edit : Mirror

Image : Zhoumian & Qinnan Map : Zheng Yi

Design : Liu Zhipeng & Zhang Qiyue

Cover image source : Visual China

Reviewer : Mirror & Wang Luzhi & Chen Zhihao

Audit Expert

Zhang Jinshuo, deputy director and research curator of the National Museum of Zoology

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