It was 1970, July.

I was among a handful of women who had a ticker tape parade down State Street,

and it was because we had just emerged from having spent

two weeks submerged in the sea. As aquanauts!

At the same time that there were astronauts flying in the sky,

you might remember, first footprints on the moon, 1969,

and there were still footprints being put there in 1970.

A dozen people have actually had the joy of seeing the world from high in the sky

looking back at this little blue speck in the universe.

It is so thrilling to hear Frans Lanting talk about that little blue speck in the universe,

to hear about the billions of years that have preceded the present time,

that have somehow, miraculously,

made this planet hospitable, for the likes of us.

It's just – when you really think about it, everything that we take for granted as children,

certainly I as a child didn't even question where air came from, it was just here.

Or the trees, the birds, the water that fell out of the sky.

Now, for the first time, we're beginning to put it together.

Just in time, perhaps. The pressure is on.

For the first time, we're beginning to see the limits of what we can do

to this place that is our only home.

There may be other places out there that look pretty attractive,

possible places where there could be water, might be life,

but to transport seven billion of us, or even a few of us,

to as close a place as Mars, is a really big deal.

We have to come to grips with taking care of this magical place that is our home.

So, If I could, right now,

I would take all of us and take the plunge into the blue heart of the planet.

You know, it was so easy to come up with the wish.

If somebody asked you, "What would you wish for?

We'll help you make it come true".

For me it was just this distillation of what I've been trying to do for most of my life,

to take care of the blue part of the planet.

The critters that live there, the water itself.

Because it does drive the way the world works.

No water, no life. No blue, no green.

It's just a fact.

97% of Earth's water is out there in the ocean.

The hard part of this challenge, to come up with a wish,

was cramming it into 18 minutes

and being able to articulate it to the world,

to do what TED asks you to do,

that is, scrunch it down and make a case for your wish.

And then maybe we'll help you out. And they have. They have enormously.

With ways of causing people to think differently about the ocean,

and it's high time that we really did so

because right now, you can go almost any place on the planet,

with cars, airplanes, walking, climbing, whatever.

But in the ocean, less than 5% of it has been seen, let alone explored.

Part of it is because we don't have gills.

It's one of the things I almost wished for. (Laughter)

Something realistic like, "Let's save the ocean."

Actually, my wish was even bigger than that.

I've taken a sidelong crack at it and that is, I'd like to have world peace.

Who wouldn't like to have world peace?

But for us to have world peace as we think of it,

making peace among ourselves,

means we must, must, must make peace with the natural world!

We are, as Jason Clay has described, eloquently,

we're chewing the planet to pieces.

We're consuming the world that keeps us alive.

And it isn't going to continue this way much longer.

If we don't take actions now - we have a chance -

but time is getting by. We have to explore.

Living underwater gave me new insights into the way the world works,

the creatures who live in the sea,

the underwater laboratory that I had the chance to use back in 1970

did not look quite like this.

This is the one that is currently in use,

one, there's just one, that really supports science,

going back to the mid-1970s, the idea began to catch on,

there were dozens of little underwater laboratories,

but over time we've kind of abandoned them,

the Aquarius, now in the Florida Keys, is still taking scientists and others

to see the world and stay underwater for days, weeks at a time.

But only in relatively shallow depths.

To go deeper one atmosphere, containers for people really seem to be the way to go,

just as going high in the sky we package ourselves,

to fly from one place to another.

We can't survive at 7 miles high in the sky.

The amount of oxygen is too little to support us,

and it's also pretty cold.

Going down deep in the sea 7 miles – huh, only two people have done this.

Only two!

Back in 1960, before there were astronauts on the moon,

but we have neglected the ocean

and the technologies that would get us to where we need to be

to understand the planet from the inside out.

I had the fun of using this system called the JIM, back in 1979,

for the first time, to be able to walk solo in a depth of that sort.

Since then I've had the chance to use these little one-person-subs quite a number of times.

They are so simple to drive that even a scientist can do it.

I'm living proof. (Laughter)

There're now about 20 of these little submersibles called "Deep Worker"

and they are out there, taking scientists and others to explore the ocean,

but we need lots of them.

We need a Hertz Rent-a-Sub. (Laughter)

And places so that you, if you want to go out and study the lakes here,

you can put one of these in the back of the truck

and drive off into the depths of the lake

or go off to the beach and into the sea.

We need to know. It's only through knowing that people can care.

You might not care if you do know,

if you know what's there, you know what's at stake.

You might not care with knowing, but you can't care if you don't know.

It starts with exploration.

And we are way behind the curve with respect to exploring the ocean.

Last year, I had the chance to try this little bubble sub

in a beautiful place where nature is still in pretty good shape:

Cocos Islands off the coast of Costa Rica.

And just a few weeks ago I was in Lake Baikal in this Russian submarine, the "MIR,"

that has the capability of going to a little more than half the ocean's depth.

About 6,500 meters.

The maximum depth: 11,000 meters.

Huh! Only two people have been to the maximum depth in all of history.

Round trip. One way trips are really easy. (Laughter)

I'm not advising that.

I'm advising that you take a look here with me,

at some of the history of going with William Beebe,

who was the first, along with Otis Barton, to see the world

as much as half a mile beneath the surface

in the waters of Bermuda.

Imagine climbing into a steel ball on the end of a cable

and allowing yourself to be dropped a half a mile beneath the surface.

William Beebe and Otis Barton were stunned with what they saw

and reported back in, for National Geographic, of course,

about the images of what they saw.

They did not have the fancy cameras that we have today.

What they had were their eyes and brain

and the ability to communicate to an artist back on the surface

who rendered images with paints and ink.

I think -- There we are.

Oh, good.

This has a voice on it and will take you into the sea.

(Video) : ...swiftest ocean currents.

(Video) : Humpback whales pass through these waters each year,

migrating from polar feeding grounds.

These waters are also known to legions of luminous deep sea creatures

and intrepid undersea explorers.

In the 1930s, zoologist William Beebe and engineer Otis Barton

descended 1,000 meters into the depths around Bermuda

for a first view of life in a place the sunlight never reaches.

(Music) (Underwater sounds)

Beebe compared what he saw to naked space itself,

out far beyond atmosphere, between the stars, with the blackness of space,

the shining planets, comets, suns and stars must really be closely akin to the world of life

as it appears to the eyes of an awed human being

in the open ocean, one half-mile down.

For Beebe and Barton, the comets, suns and stars were living creatures,

reflecting rainbows of iridescence,

were flashing, sparkling and glowing with their own living light.

Fireflies and glow worms are famous lightmakers on the land.

But in the deep sea, about 90% of the creatures:

jellies, fish, bacteria, shrimp, squids, and many others,

have some form of bioluminescence to signal one another.

Scientists say these bursts of starry light

may be the most common form of communication on the planet.

In the open sea, jellies are also among the most abundant forms of life.

The Gulfstream current can carry these oddly beautiful drifters along

at about 160 kilometers a day.

Buffered by the Gulfstream is a magically quiet, gently rotating mass of Sargassum weed

that expands over more than five million square kilometers of open waters.

Isolated by walls of fast-moving currents between Bermuda and Puerto Rico,

the Sargasso Sea holds a liquid jungle of creatures,

which have evolved over the ages to exist in floating forests of golden brown Sargassum.

Within its leafy, sunlit masses are camouflaged such creatures

as loggerhead turtles, file fish, sea hares.

Sylvia Earle: I think we'll leave it at that.

This is the only home that many of those creatures have.

It's also the part-time home for baby turtles and for young tunas,

and it's a floating golden forest.

It's a rain forest out there in the middle of the sea,

but it's even wetter than rainforests, filed with great diversity.

Actually, the ocean holds the greatest diversity of life on Earth,

no big surprise, it's where most of the water is, it's where most of the life is.

But the major divisions of life are all there.

Only about half of the big divisions of animal life have made it to the land.

Jump into the ocean and you'll meet some of these creatures that occur just in the sea.

We are just beginning to understand and appreciate

the nature of the creatures who share space with us on this little blue speck.

And it is time that we pulled out all stops and began to truly take seriously

what we're doing to the ocean, what we're doing to the diversity of life.

Every spoonful of water has creatures in it.

Thousands of microbes, literally billions of microbes,

but thousands of different kinds in a bucket of water.

In the gulp of a whale shark's maw, just one big gulp,

we may have more divisions of animal life represented

than in all the terrestrial parts of the planet put together.

It's enormous diversity. Also enormous ignorance.

And we have great power to destroy what's there.

Presently, we're looking at a time, just the last 50 years,

when 40% of the plankton is gone.

When fish, such as grouper, have declined by 90%.

And tunas. And swordfish. And sharks!

Creatures that are vital to the integrity of ocean systems.

One thing that I began to see,

spending thousands of hours in the ocean, face to face with some of these creatures,

is that they're all individuals. They're different.

They have different faces.

I suppose if a fish came swimming through this audience, looked around and said:

"Yeah, human beings, they all look pretty much alike to me."

But we know that we're all different

and so do they, I suppose, know that everyone is different,

and they recognize individuals.

But there is so much that we have to break through,

get out of our own shell and think about the world

from a standpoint of the other creatures who share a space with us

to realize that we have the power to eliminate creatures

that have preceded us by hundreds of millions of years.

Whether it's horse shoe crabs, or sharks, coral reefs or whatever.

This is a critical moment in history.

Seriously, we are at a point where we have the power to see the last of the tunas.