Natural Selection: Darwin's Mystery of Mysteries

Deep down along the East African coast hidden in underwater caves

we find the coelacanths, fish from another time.

This 400 million year old living fossils

were once thought to have become extinct along with the dinosaurs.

Possibly the sole remaining representative of the family of fleshy finned fish.

Perhaps the ancestors of amphibians that started to roam on land.

When we look at the world around us, we can tell it is not always been the same.

A top of the cliff was once the bottom of the sea.

Fossilized shells of long gone ocean creatures can be found right here.

Since the Earth was formed many exciting changes have occured.

The key is time.

The long geological history of the Earth our own human history.

In the 19th century in Victorian times people had a different perception of the natural world around them.

Most people stuck to the conventional belief that the Earth is only a few thousand years old

and is populated by species that are same today as they were when originally made

during the single week in which the Creator formed the entire Universe.

In 1842 Queen Victoria had seen the orangutan in London Zoo.

She was less than amused

"The orangutan is too wonderful he's frightfully and painfully and disagreeably human."

Around the same time fossils of large extinct dinosaurs were gradually being unearthed and described.

Even then scientists recognized that extinction had been a common occurrence in the history of life.

But how could new species appeared to replace those lost through extinction.

It was time for someone to come forward with a explanations of this mystery of mysteries.

Good morning. Lovely day.

Welcome to Down House the home of Charles Robert Darwin

during the last 40 years of his life.

It was here where Darwin wrote his famous book

on the origins of species by means of natural selection.

The book that challenge the world view that had been told for centuries.

I'm delighted by your visit.

And humble that you're here to learn about the ideas I had during my blessed youth.

I didn't enjoy or do well at school,

but not pursuit gave so much pleasure as collecting beatles.

My father worried that I would end up being a disgrace to myself and the family.

But when I was only 22 years old in 1831

I was invited to sail as naturalist on board of HMS "Beagle",

whose mission was to circumnavigate the world.

At first my father opposed it,

but at the end he was lenient it and I accepted the post.

The voyage of the "Beagle" has been by far the most important event in my life...

... and has determined my full career.

The primary mission of the "Beagle" was to chart poly-none (?) stretches of the South American coastline.

Darwin was not a hired biologist, but had to pay for his own trip

as a gentleman companion to captain FitzRoy.

While the ship cruised away the coast Darwin spent most of his time on shore.

observing and collecting thousand specimens from a wide diversity of exotic plants and animals.

Darwin's life now had purpose,

he'd followed his heart and become a scientist.

He was filled with excitement as from the early age he has a passion for Nature.

I do not believe that anyone could have shown more zeal for the most holy cause than I did...

... for shooting birds.

Captain FitzRoy had give Darwin a new book called "Principles of Geology" by Lyell, a geologist.

Lyell wrote that the Earth had been formed not in a few days,

but over a long period of time by natural processes

such as volcano and earthquakes.

Darwin was fascinated.

Then on February the 20th 1835 Charles Darwin experienced an earthquake himself...

... in Valparaiso, Chile.

The nearby town of Concepción was ruined by the earthquake.

It was one of the most interesting spectacles he had seen since leaving England.

At the same time captain FitzRoy found beds of mussel shells still sticking to the rocks...

... way above high water mark as the result of earthquake.

Darwin found fossilized shells high on the top of the Andes.

Could mountains had been formed by many, many earthquakes over a long period of time?

Darwin was sure Lyell was right -

natural forces like volcanos and earthquakes had changed the Earth in the past.

And the Earth is still changing today.

In 1835 the "Beagle" set sail for the Galapagos archipelago.

Islands of relatively recent volcanic origin

that lie on the Equator quite away west of the South American coast.

Darwin wrote to his sister.

"I am very anxious to see the Galapagos Islands."

"I think both the Geology and Zoology cannot fail to be very interesting."

This would turned out to be a huge understatement.

Darwin found the strangest creatures that seemed highly adapted to the habitat

and show similarities with creatures of the South American mainland.

Marine iguanas that feed on algea from rocks on the coastline.

Darwin wrote,

"The black Lava rocks on the beach are frequented by large most disgusting, clumsy lizards."

"They're as black as the poorest rocks over which they crawl

"and seek their pray from the sea."

He observed animal behaviours that he had never seen before.

The blue-footed booby waves and shakes his blue webbed feet

to give the female the thrill.

This are his best footlifting efforts.

Higher up on the slopes of the volcanos - giant tortoises graze.

Darwin was told by the locals

the one could tell which island the tortoise came from by looking at its shell.

It took a while before he grasped the significance of this news.

Most of the animal species on Galapagos live nowhere else in the world.

Like this flightless cormorant.

Darwin asked himself,

"Why did God create birds with non-functional wings?"

"... and fowl that may fly above the earth in the open firmament of heaven."

Darwin, who almost became a clergyman himself

never missed a single one of the Sunday services

conducted on board "Beagle" by captain FitzRoy.

"And God created great whales, and every living creature that moveth,"

"which the waters brought forth abundantly,"

"after their kind, and every winged fowl after his kind..."

And God saw that it was good.

And God blessed them saying, "Be fruitful and multiply."

And fill the waters in the seas.

Bye the end of the "Beagle's" 5 year voyage young Charles Darwin had become convinced

that life on Earth had evolved by natural causes.

We can allow planets and the Sun to be governed by natural laws...

... but the smallest insect we wish to be created at once by special act.

During the voyage of the "Beagle" I had been deeply impressed by the Galapagos archipelago.

And the manner at which species differ slightly on each island.

The natural barriers of islands seem to be a vital ingredient...

... in the origins of new species.

In order to make a solid case for evolution he needed to explain how evolution happens.

He wondered, "If the world has changed so much during its long geological history..."

"... then perhaps all living creatures somehow gradually adapted"

"to fit in with a slowly changing environment."

"Otherwise the would have become extinct."

The survival of life on Earth can only be explained by the idea

that unsuccessful species are replaced.

Then must be a natural law that explains how new species replace the old ones.

Less than two years after arriving home Darwin found his mystery of mysteries...