Cosmos: Possible Worlds - First Season

To be human has been to know the torment of hunger.

There was once a man who dreamed that through science,

we could make a world where no one would ever perish from hunger.

And famine would be no more.

He gave us a treasure to fulfil that promise,

but he faced a terrible choice at a moment of reckoning.

To lie about science and live,

or to tell the truth and face certain death.

For the first couple of hundred thousand years that

we were human, we were wanderers living beneath the stars.

We gathered plant life and hunted animals.

Until about ten or 12,000 years ago,

when our ancestors invented a new way to live.

Think of those geniuses who were the first to realize that

inside the plants they foraged,

was a means to make another plant.

A seed.

That discovery led to the single most fateful choice our species ever made.

They could continue to wander in small bands,

or they could settle down to grow and raise their food.

This required sacrifices for rewards that would not come until much later.

For the first time, we were thinking about the future.

Of course, these decisions weren't made in an instant.

They unfolded over generations.

That seems like a long time ago in human terms,

but in the great sweep of cosmic time,

it was less than a half a minute ago.

This Cosmic Calendar compresses all of the last 13.8 billion years

since the big bang into a single calendar Earth year.

Midnight on December 31 is right now.

Every month is a little more than a billion years.

Every day, a little less than 40 million years.

And all of humanity's proudest achievements unfold

in the last couple of minutes of cosmic time.

That's how new we are to the universe.

Our ancestors began to domesticate animals and

plants less than 30 seconds ago on the Cosmic Calendar.

For the first time, the wanderers were settling down.

And building things to last for more than a single season.

They dared to touch the future.

Their tower of Jericho still stands.

Was it a watchtower for protecting the city from invaders?

Or just a way to get closer to the stars?

It took 11,000 work days to build.

Something that could only be possible with the

food surpluses that agriculture provided.

This is the world's oldest stairway.

It was already 5,000 years old before the first Egyptian pyramid was built.

To climb it is to follow in the footsteps of 300 generations.

Isn't it astonishing that people who had barely ceased wandering,

we're able to create something of such permanence?

The rich and varied hunter-gatherer diet,

of plants, insects, birds and other animals, was replaced.

City dwellers largely subsisted on a few carbohydrate crops.

And when the rains didn't come or a fungus afflicted the grain,

there was hunger on a massive scale.

Famine.

Famines caused by drought and British colonial mismanagement

in India in the 18th century killed ten million people.

In China, during the famines of the 19th century,

more than 100 million people perished.

The great hunger in Ireland,

also a result of British imperial policy,

starved a million to death and

forced another two million to flee the country in search of a living.

The Brazilian drought and pestilence of 1877 was comparable.

In a single province, more than half died of starvation.

The dead remain uncounted from the famines that wracked

Ethiopia, Rwanda and the Sahel in Africa.

For a couple of thousand years,

ever since records were kept, somewhere on Earth,

people in great numbers have starved.

Could agriculture become a science with a predictive theory as reliable as gravity?

One that could consistently produce breeds able to stand up to drought and disease?

Farmers and herders knew the advantages of preferentially

selecting the hardiest specimens for crossbreeding,

to produce a more successful hybrid.

This was known as artificial selection.

But the mechanism of how those traits were passed on to

succeeding generations remained a complete mystery.

This is Down House.

Charles Darwin's home, where he lived with his wife

Emma and their ten children.

He was hardly the authoritarian Victorian patriarch.

But instead a tender, loving father who delighted

in his children's ridicule.

This is the garden he planted.

This place is a strangely pastoral setting for the most

influential revolutionary in the history of thought.

Even now, there are people who are afraid of his idea.

Charles Darwin discovered that species, including ours,

evolve over time through a process of natural selection.

The environment rewards those best adapted to its changing

realities with survival and with new generations of offspring.

Darwin demystified the external reality of life,

but no one had any idea what the inner mechanisms of evolution were.

At that same moment, an abbot at a rural monastery

in what is now the Czech Republic was trying to become a science professor.

Gregor Mendel flunked his qualifying exam both times.

The only career path open to him was to become a substitute teacher.

So in his spare time,

he took up the study of pea plants.

He bred tens of thousands of them,

carefully scrutinizing their height and their shape

and the color of their pods, their seeds and flowers.

Mendel was searching for a predictive theory of breeding.

So that you could know in advance exactly what you would

get when you crossed a tall plant with a short one,

and a green pea with a yellow one.

Mendel found that you would get a yellow pea every time.

We didn't have a word for the power of the yellow over

the green until Mendel coined it.

He called that quality "dominant."

And to his delight, he found that he could predict what would

happen in the next generation of peas after that.

One in four pea plants would be green.

Mendel named the hidden trait that popped up in the next crop, "recessive."

There was something he called "factors,"

hidden inside the plants that caused particular characteristics.

And they operated by a law that Mendel could describe

with a simple equation, like gravity.

Charles Darwin and Gregor Mendel didn't know it,

but the two scientists were deciphering the mysterious

workings of life at the very same moment.

Darwin presented the evidence for a oneness with all life.

That despite our pretensions to a mystical higher birth,

we were actually relatives to the other beasts and vegetables.

As much a part of the natural world as any other living thing.

Mendel discovered that there were laws governing the

way life's messages were passed on.

The substitute teacher had invented a whole new field of science.

But nobody noticed for 35 years.

He died never knowing that the world would come to see him

as a giant in the history of science.

Mendel's work was resurrected at the beginning of

the 20th century and he had no more vigorous defender

than the British zoologist William Bateson.

It was Bateson who named the new field of science devoted

to studying these factors.

Genetics.

Bateson and his colleagues worked on developing

new breeds of plants and animals.

He believed that science and freedom were indivisible

and that's how he ran his laboratory.

Nikolai Ivanovich Vavilov,

a visiting botanist from Russia,

took Bateson's credo deeply to heart.

He wanted to use the new field of genetics to learn

how to feed the world.

He was on his honeymoon but science was his passion.

Even as a child, Vavilov had a sense of urgency.

"Too little time, too much to do," was his lifelong refrain.

How could he have known what was coming?

The idea that our planet is a single organism,

a unity, has a ring of hollow sentimentality for many people.

But it's just a scientific fact.

Something is about to happen here, in remote Southern Peru,

in the year 1600 on February 19 at 5:00 PM.

Unsuspecting multitudes and distant foreign capitals

will never know how this event reached around the world

to torment and kill them.

This nasty mixture of sulfuric acid and volcanic ash

will block the sun's rays from reaching Earth.

Some of the sunlight will be absorbed here in the stratosphere.

The eruption of Huaynaputina volcano remains to this day

the largest explosion in South America in recorded history.

Winter is coming.

Volcanic winter.

For the people of Russia,

it brought the worst winter in six centuries.

For two years, even the summer temperatures would fall

below freezing at night.

Two million people, a third of Russia's population,

would die from the resulting famine.

It led to the downfall of the Tsar Boris Godunov and

all because of a volcano that erupted 8,000 miles away in Peru.

This was not the last famine in Russian history.

Drought and famines occur frequently.

But it wasn't until nearly three centuries later,

in 1891, that the magnitude of suffering was again as ghastly.

Winter came early that year and the crops failed.

Tsar Alexander III was slow to respond.

Wealthy Russian merchants continued to export grain at

a profit even as millions went hungry.

All the Tsar had to offer his starving subjects was "famine bread."

A miserable mixture of moss, weeds, bark and husks.

Half a million Russians perished,

while the aristocracy and the wealthy feasted on fresh

strawberries from the south of France and clotted cream from England.

The Russian Revolution would not explode for another 30 years,

but many historians believe that this famine

was the spark that ignited the long fuse.

It was to make a lasting impression on the hero of

our story, Nikolai Vavilov.

This is the Vavilov family.

The parents were born into poverty but had worked their

way up into the upper middle class.

All four of the children would grow up to become scientists.

Sergey became a physicist.

Nikolai grew up to be a botanist.