Original subtitles

Freeman: There could be an undiscovered species

lurking on the surface of the earth.

But this creature is unlike any life form

we've ever imagined.

Its body could span thousands of Miles.

It has a heart that beats once every 1,000 years

and an immune system that could wipe out

nearly all life on earth.

It may even have a brain.

Could the vast ocean itself be a living, thinking creature?

If so, what does it think of us?

Space, time, life itself.

The secrets of the cosmos lie through the wormhole.

-- Captions by VITAC -- www.vitac.com

CAPTIONS PAID FOR BY DISCOVERY COMMUNICATIONS

Resync by iscol@HDVietNam.com

We've always looked to the stars

for signs of other intelligent life,

but we may be staring in the wrong direction.

A nonhuman intelligence

far more sophisticated than our own

could be right here on earth.

Our vast ocean is this planet's last frontier.

Some scientists are asking not what, but who it is.

Have you ever felt someone's presence,

but you couldn't see them?

When I walked in the woods as a kid,

it often seemed like the trees were aware of me.

Sometimes, I thought I could hear them talking.

I wondered, "could the whole forest be a conscious being?"

Anders Nielsen has always been obsessed

with the chemical that is the foundation

of all life on earth --

liquid h2o, water.

When I was a kid, I would spend, like, every summer

maybe five hours a day swimming in the lakes,

just playing around in the water.

And these days, I love just to hang out in the water.

It's just a beautiful experience

to feel like your body's dissolving into the water.

Freeman: When Anders became a chemist,

his obsession with water grew even deeper.

Nielsen: Water has this ability

to form what's called hydrogen bonds,

where a hydrogen atom in one water molecule

could bond to an oxygen atom in another water molecule.

Freeman: Harnessing the power of the Stanford linear accelerator,

Anders took X-ray images of liquid h2o molecules

and discovered that groups of water molecules

perform an elaborate, synchronized choreography.

A single molecule of h2o is like a single swimmer.

Each can move along freely

or it can link arms with a neighbor

to form a rigid structure.

Below freezing, the molecules join at angles

and take up more space.

This is why water expands when it turns to ice.

Liquid water contains both freewheeling molecules

and rigid clusters simultaneously.

These structures form or break apart

depending on temperature.

But Anders discovered that water molecules

also change their routine

depending on what's mixed in with them.

So, here I have a sodium chloride crystal.

This is just ordinary salt like you have in your food,

what we have in the ocean.

So, if you look at this example.

[ Blows whistle ]

Freeman: When ordinary table salt comes into contact

with a rigid formation of water molecules,

that formation breaks apart.

This creates more free-floating molecules

that break salt crystals apart

and spread them throughout the body of water.

Other chemicals have a different effect.

So, here we have a very strongly or highly charged ion.

This can be like magnesium or aluminum ion.

And then we're going to throw in this,

and we're going to form an ice-like structure around it.

Water molecules lock around the ion and hold it in place.

To us, a glass of water seems still and lifeless.

But on the molecular scale, it is pulsing with activity.

Water changes its molecular structure

around 1 trillion times per second.

Whenever the molecular structure of water changes,

the overall chemical properties of water also change.

No other liquids on earth can do this.

Water molecules respond to temperature

and the chemicals they come in contact with

almost as if the water is aware of its surroundings.

For Anders, this property blurs the distinction

between a chemical and a living thing.

Nielsen: Some people might think

that a glass of water could be alive.

My personal view of life

is that it's related to something

that has consciousness on some sort of level,

and the question is if that is the case with water,

and we -- we can't say "yes" or "no."

Freeman: Whether or not a glass of water is alive,

water itself is still the essence

of all life that we know of.

About 60% of your body is water.

Cells with your DNA call it home,

along with about 1,000 unique species of bacteria.

The ocean ecosystem is also mostly water,

and home to millions of life forms.

Could ocean water and the life that calls it home

collectively be a living thing?

Is a life form that large even possible?

Evolutionary biologist Gustavo caetano-anolles

suspects it was.

He's tracking down earth's first life form,

the creature at the root of the tree of life.

A tree of life is an hierarchical structure.

That means that if you travel back in time,

you are traveling to an organism that at some point

embedded all the diversity that was generated later on.

And this is the last universal common ancestor, or Luca.

Freeman: Luca is the scientific nickname

for the first species on earth.

It lived about 3.5 billion years ago,

and is common ancestor to all life today.

Luca cells likely filled the primordial ocean,

unhindered by any competing organism.

Luca has been extinct for billions of years.

[ Camera shutter clicking ]

But Gustavo believes he can reconstruct

what its cells looked like

by studying the details of life's machinery today.

For Gustavo, finding the elements

essential to the earliest life form

is like figuring out how the very first bicycle worked.

[ Camera shutter clicking ]

Caetano-anolles: Bikes are permanently changing.

Every 10 years, we have new developments,

new mechanisms, new electronics added to them.

In contrast, the structure of a bike is rather permanent.

Freeman: Bikes today come with a variety of sophisticated gears

and high tech materials,

but all share common, essential structures.

Without them, a bike cannot function.

In the first bike, I would find a seat,

pedals, wheels,

because these seem to be common to all bikes

that I can study today.

Freeman: With a list of these fundamental parts,

Gustavo can reconstruct the last universal common ancestor

of bicycles --

the penny-farthing...

...the first machine to be called a bicycle.

It had a seat, pedals, and wheels,

but didn't need a chain or gears to move.

Gustavo applied this same philosophy to his hunt for Luca.

By comparing the fossil records

to the genetic record of thousands of organisms,

Gustavo worked out which proteins existed

about 3.5 billion years ago.

He generated a list of fundamental parts

that Luca must have had.

To his surprise, he discovered

that unlike all life we know of today,

Luca probably did not have a well-sealed cell wall.

Caetano-anolles: It is quite possible

that the cell walls of Luca were porous,

and that they would allow for fast exchange

between the different Luca cells of genetic information,

and also of actual machinery.

Freeman: Think of a Luca cell as a penny-farthing bicycle.

Because its cell wall was full of holes,

important parts could come loose and float away.

Water molecules could, however, react to this escaped part

and form a supportive mold around it

until it drifts into another Luca cell

where that part could be reused.

Luca cells depended on one another

and water chemistry to keep the entire colony alive.

Gustavo believes

that rather than being many distinct organisms,

these cells behaved like parts

of a single, giant, cooperative being,

a superorganism.

Caetano-anolles: As multi-cellular organisms

are made of individual cells,

a superorganism is composed of many organisms

that are interacting heavily with each other.

Freeman: A superorganism is a creature

made up of many individuals, like the hive of bees.

If Gustavo is correct,

the very first life forms on earth

were not isolated microscopic cells,

but rather the vast ocean itself,

a superorganism that covered nearly the entire planet.

We might all be descendants

of a single, supermassive creature.

Billions of years have passed since the time of Luca.

Is the ocean still a superorganism?

One scientist is trying to find out

by studying whether the ocean, as a whole, has an appetite.

How do you know whether something is alive?

It is a question great minds have argued over for centuries.

To the philosopher rene descartes,

the answer was, "I think, therefore I am."

But biologists have come up with a different criterion,

one that could reveal a new form of life.

The answer could be, "I eat, therefore I am."

New York university's Tyler volk believes, like every biologist,

that all living things have a metabolism.

A metabolism is a biologically active process

that breaks down certain chemical compounds

into smaller constituents,

and then rearranges those constituents.

Freeman: Every creature you can think of on the planet

has a metabolism.

Organs inside these creatures extract energy from nutrients,

then discard the leftovers.

The ocean is filled with life forms that do this.

But the ocean itself

is not usually considered a living being.

Instead, it is thought of as an enormous recycler.

Some of the elements in the ocean

are recycled hundreds of times in and out of the useful forms

that can be taken back up by life again over and over again.

Freeman: But when Tyler took a closer look

at the ocean's recycling system, the numbers didn't add up.

Life in the ocean recycles essential nutrients

like carbon, phosphorous, nitrogen, and sulfur

through a process of life and death.

Life feeds on life, which feeds life,

which feeds other life, and life is renewed.

It's a near-perfect recycling system.

Tyler has tracked precisely how efficiently

each of these nutrients gets reused.

His analysis reveals

that not every life-sustaining element in the ocean

is 100% recycled.

Volk: The calculations show

that as marvelous as these biochemical cycles are

inside the ocean, they're not perfect.

There is a need for fresh elements,

the chemical elements essential to life.

Freeman: Tyler argues this imperfect recycling

means that the ocean, a giant system of life,

has a metabolism.

Just like us, the ocean feeds.

Volk: So, what we call the mouth of the river,

you can think of as the mouth of the ocean.

These are the portals

by which very important materials come into the ocean.

Freeman: And, after it metabolizes its food from rivers,

it excretes waste into the ocean floor.

Volk: In the ocean, there will be waste byproducts.

There will be certain compounds that will go into the sediment,

get covered up, and not get recycled

by the microbes or by the worms.

Freeman: Tyler thinks that even though they feed on one another,

life forms in the ocean are ultimately working together,

like organs inside a body.

One group, which includes fish and mammals,

works like the human respiratory system.

It takes in oxygen and carbon

and transforms it into carbon dioxide.

Another group, ocean plant life,

takes carbon dioxide and transforms it into oxygen.

Still another group, comprised of bacteria,

processes nitrogen into ammonia.

For Tyler, treating groups of life forms in the ocean

as metabolic organs in a giant body

is not just a metaphor.

It could reveal exactly how the ocean as a whole

will react to chemical changes on planet earth.

Volk: To know how the carbon dioxide in the atmosphere

will respond to changes that humans may make

in their industrial processes,

one has to understand the entire cycle of carbon.

And that's going along with other nutrients,

such as phosphates carrying the phosphorous,

nitrates carrying the nitrogen.

And so all these are tied together

into one very tightly interconnected,

coupled metabolic supersystem.

It is a form of superlife.

Freeman: Tyler thinks

that if the ocean is a form of superlife,

it will, like all living things, react when threatened.

Many scientists believe

that we are poisoning earth's waters.

Does the ocean and all the life within it

have a collective will to live?

And what will it do to stay alive?

[ Siren wails ]

When our bodies get sick,

an army of cells, tissues, and organs work together

to protect us and fight off disease.

What happens when the ocean gets sick?

Does it have an immune system of its own?

And what happens when this immune system kicks in?

Mainstream science does not typically consider the ocean

to be a living being.

But that hasn't stopped geologist Lee kump

from studying its physiology.

Kump: Physiology is the study of how organisms work.

It's the study of the whole organism,

how it functions as a living being.

[ Fly buzzing ]

Freeman: All living organisms

obey the same basic rules of physiology

no matter how big they are or how small.

Kump: When you think about a fly,

it has the same physiological mechanisms

that we have in our own body.

And key to this is the circulation system of the fly.

Really, the only difference

is its heart beats five times per second,

ours about once per second.

So, now we scale up to something like the ocean,

and it, too, has a heartbeat.

And that heart rate is about once every 1,000 years.

Freeman: The ocean's 1,000-year-long heartbeat

begins in the north and South poles.

Water gathers oxygen from the arctic and antarctic air.

As the water cools, it sinks to the bottom,

bringing oxygen to deep sea life.

It flows along the dark abyss until it reaches the equator,

where it warms and rises to the surface.

It moves towards the poles, and the cycle repeats.

So the oceans, just like the human body,

needs to circulate for it to function.

Freeman: Whenever harmful microbes get inside us,

immune system cells rush to the site of invasion

and neutralize the threat.

Lee argues that the ocean's 1,000-year current

is a true physiological circulation system

because it, too, delivers antibodies to infection sites.

Every circulatory system has an essential player

in our bodies and our bloodstream.

That's our cells.

And in the ocean, it's bacteria.

Freeman: In humans, outside bacteria

are usually a threat

to be fought off by our immune systems.

But in the ocean, bacteria are the immune system.

Kump: They're very tiny. They don't sink.

And so they get carried around

with the circulation of the ocean.

They can break down harmful substances.

They can detoxify them.

Freeman: The ocean is home to bacteria

that travel on the currents and break apart harmful metals,

toxic chemicals, oil spills,

and just about every harmful substance

that can work its way into the ocean.

Just like life on a college campus,

keeping everybody safe is a team effort.

[ Siren wails ]

Hm.

Imagine an arsonist

who sets the student center ablaze.

Uh-oh.

What?

The first responders are the firefighters.

In the ocean, these are the bacteria

that feed on the newly arrived toxin, and multiply.

Kump: This is the bacteria being transported

with the ocean currents.

Where there is a toxin introduced to the system,

the bacteria thrive and detoxify.

Freeman: Once the toxin is eliminated,

the bacteria die off,

just like the first responders who leave after the fire is out.

But they leave behind a bunch of byproducts.

So the bacteria are producing waste.

That's influencing the chemistry of the oceans.

As the ocean's chemistry changes,

that in turn influences the bacteria themselves.

Freeman: This instigates another wave of bacterial helpers,

and another,

until conditions stable enough for normal life return

and the harmful toxin is completely neutralized.

Hey, stop!

Put your hands behind your back!

But just because the ocean has an immune system

does not mean that it's invulnerable to catastrophe.

When our immune systems overreact,

we develop severe diseases like multiple sclerosis.

These immune systems can overreact,

and they can produce too much antibody.

They can disrupt the physiology of the organism.

In the ocean, we can get that same sort of overreaction,

and carry us into a whole new state of the ocean,

an unhealthy state.

Your immune system protects you from disease,

but if it overreacts, it can kill you instead.

What would happen if the immune system of the ocean overreacts?

It may have already happened

at least five times in earth's history,

resulting in the extermination

of nearly every living thing on the planet.

When a honey bee perceives a threat to its hive,

it will sting its victim

and release toxic venom that can be fatal.

After the bee stings, it dies.

The honey bee's instinct is to defend its hive at any cost.

Will life in the ocean do the same?

Peter ward is an oceanic paleontologist

who likes to get up close and personal

with the subject of his studies.

Ward: I dive a lot. My science requires it.

And yet, I come back,

I just can't describe in words what it's like.

I just cannot bring out the vision

of what I'm seeing and thinking down there.

Movies are way better.

I bring back small videos,

and you really get a sense, I think.

A picture may be worth 1,000 words,

but a short video is worth millions of words.

Freeman: But don't let Peter's tranquil footage fool you.

Beneath the waves,

Peter is looking at a crime scene

where millions of species all across the globe

suddenly wound up dead.

Ward: So, 99.999999% of all individuals --

a mass extinction not only wipes out a species,

but it really empties the earth of life.

These are really hideous events.

Freeman: For years, scientists thought

that all mass extinctions were caused by climate change

brought on by asteroid impacts and massive volcanic eruptions.

But Peter thinks there's another mass killer.

[ Creature roars ]

Ward: We started looking

at the other mass extinction boundaries.

None of the evidence of an asteroid collision

were showing up.

In fact, something quite different.

Freeman: Peter and his colleagues have studied the fossil evidence

and pinpointed the murder weapon,

a lethal chemical that can be found in trace amounts

on nearly every shoreline on earth.

Ward: Wow, look at this.

[ Sniffs ] Oh, ho, ho.

So, what makes this so stinky, and it really is stinky,

is it's full of hydrogen sulfide.

Hydrogen sulfide is a gas

that is extremely poisonous to we mammals.

There are many bacteria who love it,

who need it to live, but not our kind.

Those of us who use oxygen, who love oxygen,

this is a very, very bad, bad poison.

As few as 500, 600 of these molecules

in a million molecules of air will kill you.

This is the stuff that literally sits at the bottom of the ocean.

Freeman: Peter believes

the bacteria that produce this deadly nerve gas

have waged chemical warfare on the entire planet,

in the sea and on land,

resulting in the death of nearly every living creature.

And it has happened at least five times.

Peter wants to predict

when this lethal bacterial plague will overrun the ocean

and flood our atmosphere with hydrogen sulfide again.

All right, let's say

that this is nice, cold, oxygenated water,

and it's been moving up from the Gulf stream,

and then north towards Europe,

getting colder and colder and colder.

And finally, it's cold enough, it sinks.

And when it sinks, what happens?

We get this nice, oxygenated bottom water

that covers the bottom of the oceans,

keeps the oceans healthy.

So, we have this nice circulation system.

Freeman: But that can change

if oxygen-rich seawater stops sinking to the ocean floor

where it's needed.

The deep sea, if there is no oxygen in it,

starts favoring other types of bacteria

that produce hydrogen sulfide.

Freeman: When the ocean surface warms by just a few degrees

or is flooded with fresh water,

it becomes less dense than the water beneath it.

So, let's make a really, really, really warm world

instead of that nice, cold oxygen water.

Let's pour in this nice, hot low-oxygen water.

You can see the hot water stays right on the top.

It doesn't go down and take the nice oxygen down.

We, instead, have a system

without an oxygen export to the bottom.

And the net result in the end is mass extinction.

Freeman: Without oxygen in the deep sea,

hydrogen sulfide-producing bacteria thrive

and fill the ocean with poisonous Violet sludge.

Large plumes of toxic yellow hydrogen sulfide explode

and blanket the atmosphere.

Plants are suffocated to death.

Animals die from poisoning.

Human life would be impossible to sustain.

Could it happen again? Absolutely.

Freeman: Peter thinks that if we warm up the planet

by just a few degrees,

the ocean could make us pay the ultimate price.

But for Peter, that does not mean

the ocean is itself a living thing.

Microbiologist Yuri gorby is taking a different approach.

He's found evidence that suggests

the ocean ecosystem is a living superorganism

with the capacity to think.

Does the ocean have a brain?

How did we get our brain power?

Well, during millions of years of evolution,

groups of cells developed electrical connections

to one another and became complex networks.

The entire ocean seems to have a similar network.

Has it evolved to be intelligent like us,

or has it surpassed us?

Microbiologist Yuri gorby is part of a team

that has made a major discovery.

It's one that could forever change

how we look at life in the ocean.

But it started with a humble question.

How do microorganisms breathe?

Now, we think that breathing in is respiration,

but that's really inhalation.

True respiration in our body occurs in mitochondria.

Respiration is the movement of electrons

from an electron donor

to an appropriate electron acceptor.

Freeman: Most species respire

by dumping electrons onto oxygen atoms

inside their mitochondria.

But a lot of aquatic bacteria respire

with a different technique.

They dump electrons onto metals dissolved in seawater.

Yuri wanted to see what happened

when he robbed these aquatic bacteria

of their life-sustaining metals.

Gorby: We expected that these organisms

would basically suffocate and perish.

But that is not what we observed.

What we saw blew our minds.

Freeman: Yuri's bacteria survived

and grew what appeared to be a vast scaffolding of tiny hairs.

Gorby: I sent some samples to a friend of mine,

and she put them under one of her microscopes,

a scanning tunneling microscope. She applied current.

She called me up and said, "you're not gonna believe this."

I rushed over to her lab,

and what I observed was that these little filaments

actually had electronic or conductive properties.

I could not sleep for days after seeing those results.

It was just remarkable.

Freeman: The tiny fibers were not hairs at all.

Yuri discovered

they were electrically conductive filaments.

He named them bacterial nanowires.

These nanowires form when bacteria need to respire,

but they stick around when conditions return to normal.

In our brains, we have about 100 billion

electrically connected cells that process our thoughts.

Yuri believes that the ocean also contains

vast electrical networks

that comprise up to 100 trillion, trillion

bacterial cells.

This network is highly interconnected,

just like the one in our brain.

It, too, may be capable of thought.

So, what do we have here?

We have a cell, represented by this light bulb,

sending a signal down a wire.

This little junction, it has to make a decision.

Which way do we propagate that signal?

To the left or to the right?

Freeman: When a signal propagates

through a digital computer,

it encounters transistors which decide

whether to turn it into a one or a zero --

left or right.

In an organic computer,

the transistors are replaced by cells,

which can pass the signal onto one or more,

or potentially thousands of connected cells.

When multitudes of these cells are interconnected,

a network emerges

that can process vast amounts of information.

Gorby: If you really ponder the question

"can the ocean think?", you have to expand your mind.

It's the same way as, "can a single bacterium think?"

No.

Can a community of microorganisms think?

Perhaps.

Expand that further.

Can the ocean process information and think?

I say absolutely.

Freeman: The ocean could have a brain

made up bacterial nanowires

that exist all through the upper layers of ocean sediment.

This brain could be capable of thoughts

very different from our own.

There are 100 trillion, trillion cells in the ocean sediment,

far more than the number of neurons we have,

and the ocean's electrical network

fires over a 1,000 times faster than our neural network.

Yuri suspects that this brain network

is spread across 140 million square Miles of ocean floor.

If so, its thoughts would play out

over hundreds if not thousands of years.

So, what could the ocean be thinking?

The ocean's been around a long time,

and those organisms that are at the bottom of the ocean,

possibly integrated into these neural networks,

they've been around for billions of years.

So, it's probably very contemplative thought.

Freeman: If the ocean ecosystem collectively forms

a living, thinking being,

it could see us as a threat to its survival.

It may decide to immunize itself against us.

We could be wiped out.

But we are also intelligent creatures.

Couldn't we learn how to read the ocean's mood?

We could be on the verge of killing the ocean.

Or is the ocean ready to wipe us out?

Determining the health of this massive body of water

is a huge task, but it's a necessary one.

The answer could tell us how much time we have left.

David marcogliese is a research biologist

who likes to look at complex ecosystems

from a bird's eye view.

Marcogliese: A city is basically an ecosystem of its own,

and we could consider this an ecosystem.

And if we look at each train as a food chain,

then we can measure nutrient flow.

Freeman: The food chain transports nutrients

from organism to organism throughout an ecosystem,

just as trains move food to whoever needs it.

If the train stops running, food becomes scarce,

and the whole town risks collapse.

Knowing if the trains are running

in a model city in your basement is easy.

But when it comes to the ocean, researchers are in the dark.

Marcogliese well, the ocean is an extremely, extremely complex ecosystem.

As ecologists, it's very difficult to look at an ocean.

It's just so big.

And it's composed of many, many different ecosystems.

Freeman: But David thinks he knows what to look for

to determine the condition of the ocean.

Parasites.

These tiny monsters survive by laying eggs into their hosts

where they grow and multiply.

Some slowly kill their hosts over years of painful invasion.

But David sees them in a different light.

Yeah, they really do have an awful, awful reputation,

and it's -- it's not surprising to think why.

There's a big yuck factor.

Because if you catch a fish

and it's covered in parasitic cysts

or you open up a COD and it has a COD worm inside,

most people don't want to eat the fish.

It's just extra protein in most cases, but anyway...

[ Chuckles ]

Freeman: In individual animals,

parasites are often signs of disease.

But for ecosystems, a rich diversity of parasites

is an indication of good health

because parasites, like the seal worm,

rely on a food chain linking many thriving species.

The adults live in seal stomachs,

and there they reproduce,

and eggs are passed out into the water.

Freeman: The eggs settle, and a tiny larva hatches.

A crustacean comes along and ingests the larva.

That crustacean is eaten by a larger crustacean,

which is eaten by one of many different species of fish,

which most seals find tasty.

Inside the seal's stomach, the worms mate and lay eggs.

The eggs drop out through the feces,

and the cycle repeats.

In one life cycle, a parasite can travel

through the dinner of multiple species

and potentially thousands of Miles of ocean water.

If something is going wrong with any host along the way,

the parasite dies.

Marcogliese: When you have a healthy ecosystem

with a good amount of diversity or biodiversity in it,

you will see more internal parasites

that have complex life cycles.

Freeman: To test an ecosystem,

David takes a census of its parasites.

Even though David can't see the whole ecosystem,

the parasites tell him

that nutrients are properly cycling through it.

We think of each parasite as a little light.

The green light is one species,

and the red light is another species.

We can then watch them follow this linear path

up the food chain,

stopping along the way at the various stops

which reflect the different hosts in their life cycles.

Freeman: If populations of parasites begin to disappear,

it could mean that there are breaks in the food chain,

and the environment is headed towards catastrophe.

David monitors the ecological health

of the rivers and lakes across Canada

by surveying the parasite populations.

Doing the same for the ocean will be a herculean task,

but David hopes one day to take it on.

Marcogliese: The ocean is such a vast habitat.

It's another frontier.

You would need the kind of resources you need

to go to the moon.

Freeman: Scientists don't know

what's really out there in the sea,

and no one knows how far the ocean can be pushed

before catastrophe strikes.

The ocean may have a will to live,

or it may react unthinkingly to our insults.

Either way, we should not underestimate

the power it has over all life on the planet.

With its millions of species, the ocean might be

the most remarkable creature we'll ever meet,

the largest and oldest life form on earth.