Original subtitles

We take our way of existence for granted.

But there are other ways of being.

The octopus has followed a different evolutionary path,

making them different from all the other intelligent animals

on this planet.

But me, I'm less intrigued by the differences

and more interested in our similarities...

..and the nature of a relationship I might have with such a creature.

This year, I got to experiment with an idea.

What would I find out if I invited an octopus...

..into my home?

What kind of connection is possible

with an animal that has three hearts

and blue blood running through its veins?

My name is David Scheel.

I'm Professor of Marine Biology at Alaska Pacific University,

here in Anchorage.

I've studied all sorts of animals,

but for the last 25 years my focus has been on octopuses.

I have two girls.

Juniper is away at university right now,

and Laurel is with me about half the time, lives here.

Laurel's 16, she's in tenth grade.

We should check with her, make sure Dad hasn't screwed that up.

Hey, Laurel! Yeah?

You're 16, right? In tenth grade?

Yeah! There we go.

I'm going out on a limb a little,

taking my octopus fascination one step further.

I'm going to fill my living room with a large tank of salt water.

I got divorced,

and the ex took some of the living room furniture,

most of the living room furniture.

My daughter's in and out of the house,

but she was eager to have a pet.

And so, this is a compromise

between a girl who really wanted a dog

and a dad who's overly interested in octopuses.

Actually, it's not a compromise.

I got the octopus.

Yeah, you have the lamp.

So it's lit?

Yeah, so it's lit, and, um...

Inviting an octopus into your home is no small undertaking.

Ah, have we got it?

All right, yeah, it's coming. Now it's coming.

All right, here we go.

This new set-up is going to allow me to spend more time with an octopus

than I've been able to do otherwise.

When I spend time with an octopus in the wild,

I visit them for only as long as I can stay in the water.

Here in Alaska, I work with the species

that's native to these cold waters,

the giant Pacific octopus.

This has been a fantastic site.

There's maybe a dozen or more octopuses

that we might be able to find,

at depths from ten feet deep to 90.

These are the largest octopuses in the world.

They can be as big as I am.

Like all octopuses, they are solitary animals.

And they are hard to find.

But they do leave us some signs.

They bring their prey back to their den,

and they eat it at their den.

And then they throw the hard shells outside the door.

And we call that pile a midden.

You can get a lot of information by looking at their garbage piles.

Place your hand outside the den

and an arm might stretch out to touch you.

Sometimes they're a bit too enthusiastic

and they grab your mask.

You don't want to let them get a hold of your air supply.

You know, they have eight arms, I have two.

So, they win.

They're sort of the gentle giants of the ocean.

They can be really large,

but they're very graceful animals.

They sort of flow from one place to another.

And I like to watch how they use their different legs.

Sometimes they're creeping on their suckers,

sometimes it's sort of they're just following the lead-to arms.

And then other times, you can see this sort of walking behaviour

going on with the rear arms.

Down here, I'm in their realm,

and I often wonder, "How do they see the world?"

And this is what my plan at home is all about,

to spend a little more time in an octopus encounter.

To consider - how do they see the world?

How might they see us?

Well, I didn't want a giant Pacific.

I wanted something that was different,

something that will be new to me,

a warmer water species, that's faster, more active.

This is a species that's been kept in aquariums

to be studied for its intelligence.

It's an Octopus cyanea,

known as the day octopus.

They call it that because, unlike some other octopus species,

these guys are active during the day,

and so you get to see them more.

Yeah, pulling hard.

Well, just a minute, I'll put you in the tank.

No. No, not yet.

Not yet.

Just a minute.

There you go.

There you go.

There she goes.

Oh, nice colour change.

Oh, look at this.

Nice.

I guess the big thing for me about keeping an animal in the home

is it's just more relaxed.

If I don't want to do anything, I don't have to do anything -

just see what the animal does.

And I'm not trying to do science here.

I'm just trying to think

a little bit.

So, it's just a chance to be

more available

and more present for whatever the animal's living, day-to-day.

She's very careful to keep her eyeball in view of mine.

And she's already checking me out.

I always get the sense when you're scuba diving

that they play this game with you.

Octopuses adapt their environments around them to their own liking.

They clean out a hole under a rock or in a crevice,

blowing out sand and debris with their siphon.

And at that point, it's not just shelter.

It's home.

Hey there.

Are you interested in some food?

Octopus love crab.

Oh, there it is.

She's definitely feeling for it.

Oh, oh, oh, oh!

She's after the tube, not the crab.

There we go.

There we go. Oh!

All right, look at the colour pattern.

That is a satisfied octopus.

I like the texture she's put on.

She didn't have that before.

The papillae coming up around the eye,

and the sort of bumps and things all over her head.

It's very nice.

Now she at least will know that the tube

and the environment have interesting possibilities.

Laurel is also going to be helping me take care of the octopus.

You know, the octopus is very happy to see Laurel every day.

Hello.

Laurel was just glad to have a pet that was glad to see her.

Yeah, I think a lot of her pets are kind of indifferent to her.

Her goldfish and her rabbit outside.

You want to come over here?

So an octopus is kind of fun, cos it comes running.

Looks like she's coming back over.

Laurel would send me little video clips

of the octopus getting up and waiting on the glass,

and ready to play.

And, you know, I'm sure Laurel looked forward to it every day.

Come here, Heidi.

Some of the things that she would do remind me

of what, like, dogs would do.

Oh, you're already up there. Come here.

She comes over to the wall of the tank

and just kind of like all excited to see you.

And so, being an intelligent animal

means that you need a lot of stimulus,

so being played with or having just, like, interactions

with people is entertaining for her.

Laurel at times, she'd sit for 30 minutes with the octopus

just holding on to her,

then wait for it to let go.

And now she took something.

So she'd sit there with her hand in the aquarium for 30 minutes,

so they're pretty affectionate.

She's filming more of the sand right now.

Well, now she's filming me.

Hi, Heidi!

The reason we call her Heidi was cos, when we first

got her, she spent a very, very long time in her den

and she was just hiding the whole time.

She didn't seem to want to come out and then,

basically once we taught her that we meant food,

she just grabbed on and was like,

"OK, I'm keeping you with me."

The cephalopod community, we're all excited about octopuses,

and we're a fairly close-knit group of researchers -

share all kinds of different experiences and advice.

Well, hi there. Hi, David. How are you doing?

All right. How are you?

Bret is an expert on the early stages of cephalopod life,

that group of animals that includes octopuses,

cuttlefish and squid.

Exactly. So how's everything going over there?

Cos I've never kept an octopus in my living room before.

You want to take a look at the set-up?

Yeah, I'd love to. All right.

Let's see if I can get the computer over there and show you.

So, she's actually out right now.

Oh, yeah. Yeah, yeah. That's great.

She's got a good marbled colouration going on there.

My day octopus is already a few months old.

There's a rock she's sitting on, so...

But at Bret's lab, we can get a glimpse into the first few weeks

of a cephalopod's life.

We're watching the mother until she starts

going through her egg-laying phase.

And once she starts laying her eggs,

she'll sit there and pulse jets of water over her eggs.

What that does is basically keep them oxygenated,

and the eggs continue to develop

until they get to basically look almost like

little octopuses inside of each individual egg.

And then we know they can kind of hatch at any time.

This is one of the few places you can see octopuses hatch

from the egg.

From this moment, octopuses are on their own.

The first instinct of this hatchling

is to construct a den out of whatever it can find.

Baby bobtail squid hide by sticking grains of sand to their bodies

with a mucus extruded from their skin.

These are all hard-wired little predators.

They don't hesitate to take down prey

even when it's two or three times their size.

Their colour-changing cells start flashing...

..while they're still in the egg.

Three types of cells with neural control

make colour change almost instantaneous.

These young pyjama squid use this

to produce their signature striped pattern.

But there is one cephalopod

that is the master.

Just a few centimetres long,

these baby flamboyant cuttles...

..can beguile anyone

with a shape-shift that is out of this world.

The day octopus can also perform an extraordinary display

with their skin.

And I already have some experience with these octopus in the wild.

I've been in the water with them

on the southwest coast of Madagascar,

working with local Vezo fishermen,

designing a way to census the octopus population.

Breece has an amazing ability to find the octopus

in amongst the coral.

Do you see there? Oh, yeah. The head.

Yeah. Do you see? Yeah.

It's amazing to me how fast they are here.

The octopuses in Alaska, they're kind of big, slow giants

and these guys are just quick and agile and limber

and really everything they do they seem to do it at ramped-up speed.

I've had them in my hands and then they're already gone.

And then I look over and Breece has caught it again.

Its face is the strangest of them all.

The day octopus is a master of camouflage.

Its skin can change colour in milliseconds.

And it can use muscles on the surface of its skin...

..to change texture as well.

And this species has recently been recorded

demonstrating an incredible behaviour with its colour displays.

It's a display called passing cloud.

It's just so stunningly beautiful.

It's like, wow, what's that?

The thing about passing cloud is it's a very impressive

physiological ability...

..and at the same time it's a bit of a mystery.

The most common theory you hear

is that octopuses are using passing cloud to startle its prey.

Trap it in the web of its arms.

My octopus is showing impressive colour changes of her own.

Observing what we're doing.

We've seen how closely the octopus we have here at the house

is watching our eyes.

You look at them and you feel like they're looking back.

That's not an illusion. They are looking back.

And so, when you're an animal that's that attentive

to another animal's eyes,

that is very suggestive of high level of awareness of the world.

Well, scientists do find questions about octopus intelligence

particularly intriguing.

At the Seattle Aquarium, they did some experiments giving different

objects to octopuses and recorded what happened.

In one of the most telling experiments,

the researchers put a pill bottle in the tank

with just enough air in it to float.

There was no food or anything to be gained here

but still a few octopuses found reason to be interested.

Nothing happened at first,

but after the fourth time, the octopus would, erm...

..would bounce... take the pill bottle,

and blow it out into a stream of water

that was circulating around the tank.

There it goes.

And the water would bring the pill bottle back to the octopus again

and it would start the whole thing over again

and it would do it again and again -

blowing the pill bottle into the water until it came back

and then blowing it back into the water again.

A bit like bouncing a ball.

The conclusion from this experiment was simple.

It fit all the criteria for play.

Play, of course, is something that intelligent animals do.

And Laurel spends many hours playing with Heidi.

SHE LAUGHS

Now... Now she's... Now you say hello to me.

Octopuses have up to 240 suckers on their arms.

Each has sensitive chemical receptors.

Heidi can touch and taste Laurel at the same time.

She just lightly jetted at me.

She doesn't want me to leave.

Octopus also have oestrogen, like humans do.

Is it possible that Heidi can be detecting the oestrogen

on Laurel's skin?

Does Heidi maybe taste the difference

between males and females?

Heidi!

Her arm is now up my sleeve.

That's fun. Heidi!

You're... You're being...

You're being naughty.

She's lifting herself almost all the way out of the tank right now.

Come here. Come here.

Come here.

Oh!

Now I'm wet.

The idea of Laurel having any kind of relationship with a mollusc

is extraordinary when you think about it.

This is an animal that has 600 million years

of distance from us.

That's almost as deep as any divide can be between two animals.

With three hearts, no bones, a beak with a venomous bite

and a gut that runs through its brain,

to one point of view, the octopus is completely alien.

As science fiction movies have long demonstrated,

humans spend a lot of imagination

dreaming up what it might be like to meet an alien.

In the latest blockbuster, Arrival,

the film-makers imagine what it might be like to encounter

a species that changes the way we think about the universe.

And I think it's an important observation

that they culminate this encounter

with cephalopod-like figures from outer space.

To really understand quite how alien octopuses are to us

and to every other intelligent form of life on Earth,

we need to appreciate the unique evolutionary path of the octopus

on the tree of life.

It's octopus lecture 101 for my students.

OK, what does the tree of life look like?

Here are a couple of artistic versions.

Now just to give you a quick overview,

here's the plants, here's the animals,

this is the branch that has the vertebrates...

VOICEOVER: To meet the common ancestor of humans and octopus,

you would have to travel back in time

more than half a billion years...

..millions of years before any animal crawled out of the ocean

on to the land.

So here's the octopus and here's the human...

..and their last common ancestor

is something that was fairly like a flatworm.

And what would this common ancestor look like?

Well, maybe a little bit like this.

A small, flat worm.

Barely any eyes to speak of,

with a cluster of neurons forming just a pinprick of a brain.

From this beginning, one path of evolution

gave rise to every bird and every reptile, every mammal,

all of them, us included,

all adaptations from this common ancestor.

Designs of eyes and brains and hearts

becoming ever more sophisticated and more varied.

That was the path for every intelligent animal...

..except for one.

That is why people talk about meeting an octopus

being like meeting an alien.

Because octopus branch of life evolved on its own separate track,

inventing its own version of an eye,

its own version of a brain,

its own version of a heart.

The octopus is a unique expression of evolution...

..so any contact I have with these animals

is possible because evolution built our eyes,

our minds, our behaviour, twice over.

There is no other intelligent animal on the planet

that has evolved separately from all the other animals in this way.

And this is why people are so fascinated to make contact

and to understand every facet of this very particular sentience.

In aquarium tanks

all around the world,

octopuses have been put through their paces.

They've solved complex mazes...

..even learnt symbols,

passed memory tests for their rewards...

..learning from feedback, forward-thinking,

applying diverse behaviours to novel situations.

When you stack them one on top of another,

that's what we call intelligence.

And the unique evolutionary journey of the octopus....

Come on, Heidi.

..makes this intelligence particularly intriguing.

For a start, the intelligence of an octopus

is not just gathered as one lump in its head, like it is with us.

Parts of the octopus' intelligence are distributed in its arms.

And that means that, to some extent, the body can be its own controller

rather than having a body being driven

entirely around by the brain.

Eight arms, independently gathering data

and reacting to the world around them.

All kinds of intelligence require feedback.

I think that's why humans are intelligent,

is cos we just, you know...

"No, you try and you learn from your errors,"

so trial and error is really the intelligent thing

and octopuses make trial and error do more than you might expect.

Heidi and I are playing around,

recreating an early one of these experiments into octopus cognition.

In 1959, a Harvard scientist asked a simple question.

Can an octopus learn to pull and release a lever to get a reward?

That experiment was successful

and so, I thought, wouldn't it be fun to play with whether Heidi

would be interested in manipulating something outside of her tank?

And so this is sort of a way to see if she can learn that

when she gets the light to turn on, she can bring us into the room.

It's kind of an interesting thing to play around with.

When you pull on the string, a light goes on...

BUZZER

Ooh. And the buzzer.

HE LAUGHS

Want to chase the ball?

Come on. Up here.

Come on.

The concept, which didn't get fully explored,

was can she learn that by doing something in the tank,

she can affect my behaviour when I'm not actually in view?

That's it. Come on.

There you go. That a girl.

Come on. Oh.

Oh, you got it. Oh!

BUZZER You vicious predator!

BUZZER

So I was curious about, does the octopus retain enough of a concept

of the person not present in her view

but present in her mind?

You going to get it, Heidi?

BUZZER

It's on.

Well, hi.

You get it?

Well done.

BUZZER

It didn't take her any time at all to learn

that there was a cue over here.

You want some shrimp?

But the rest of it, you know, that was...

..challenging.

BUZZER

This idea was more fun in the concept

than at any point in the execution.

Yeah.

Heidi got fairly insistent.

BUZZER

And I decided to take this all apart.

HE LAUGHS

Our understanding of octopus intelligence

took another leap forward when in Indonesia, in 2009,

researchers reported a veined octopus

doing something truly remarkable.

It was a discovery that would put our understanding of the octopus

onto a new level of sentience

occupied by only a few species of animals.

Living on the sand flats, they have very few places to hide,

but this octopus has a unique solution to the problem.

It carries half a coconut shell with it.

But it needs to find something else to complete the set.

Two coconut halves.

A perfect shelter.

What is remarkable about this discovery

is how the octopus dismantles its home...

..carries it around...

..uses it to hide and to ambush prey...

..and now it's putting it back together again.

This octopus is thinking ahead.

This is real flexibility.

The octopus has to anticipate to carry that awkward object around

and then correctly assemble the separate parts

to create a single functioning tool.

And less than 1% of all animals have ever been seen to use tools.

And it's not just science that is starting to take notice

of the extraordinary octopus.

Laurel was showing me all the attention these animals

are getting from people.

I've seen Heidi do this before. Yeah.

So my real question on this one is, who's taking the video?

Is it another octopus who stole the GoPro?

LAUREL LAUGHS

Maybe he's filming himself.

Yeah, he's doing a blog.

Oh, yeah. Video blog!

Yeah.

And he's like, "Look at this strange thing that came and found me."

We're no longer just eating octopuses.

People are meeting them now - making contact in the ocean.

I held a fish in front of his shell and he grabbed it from my hand.

He touched my finger with his arm

and I think that we were both a bit surprised, so we both pull back.

This time he grabbed my finger and he tried to pull my finger inside

but I was really surprised by his strength.

This clip has 11 million hits.

He was punching the fish away with his arms.

It was the funniest thing I've ever seen.

This octopus trying to punch away little fish.

It was definitely the coolest encounter I've had with an octopus.

I tried to see how he responds to different objects,

like a cone shell or a mirror,

but he never really respond the way that I expect.

For example, he was not interested at all in a cone shell

that I gave him, but he kept going up to my hands

and he kept feeling my little elastic band around my wrist.

I went on holiday and I didn't see him for a few days before.

I was worried he wouldn't be there any more when I came back.

But I found him and he swam up to me and he touched my foot.

985 clams disliked this video.

That's funny.

This one also went viral.

It wasn't hard to get Heidi to demonstrate

these impressive skills of contortion.

She doesn't have a skeleton.

Want to go through?

Come on, Heidi. Come out and play.

Come on.

Octopus are able to squeeze through the smallest of gaps.

That a girl.

That's it. Come on, sweetie.

Good girl. Come on.

Come on.

A little squeeze.

There we go. That a girl.

Keep coming. You can do it.

Almost.

You can squeeze.

I need to be very careful.

This ability makes Heidi a real escape risk.

She is quite capable of leaving the tank if she gets a chance.

In fact, octopus can move across land with surprising ease.

In northern Australia,

it's part of the hunting strategy of the Abdopus octopus.

Octopus have gills, so they can't survive out here for long.

But they do absorb some oxygen through their skin...

..allowing them enough time to find a new rock pool

with new opportunities.

And leaving the water is not just being seen in the wild.

There's stories everywhere.

There's far more stories than there are data.

One story tells of a trawler in the English Channel

and an octopus caught in a net left on deck.

Somehow it manages to slither from the deck

down the companionway into the cabin

and, hours later, is found hiding in a teapot.

Now we turn to a tale of escape.

A daring act by an octopus.

Inky, the octopus.

In a New Zealand aquarium,

another octopus named Inky

becomes famous on the news

when it was reported for escaping its tank

and crawling across the floor, disappearing down a drain,

escaping to the sea.

The manager of the aquarium says Inky will not be pursued.

Some of my favourite stories are about pet octopus

popping out of their tank...

..to snack on their neighbours.

People notice their fishes going missing in the middle of the night.

They discover that an octopus might sneak out

under the cover of dark...

..and then return unnoticed.

My investigations into this suggest an octopus leaving its tank

to grab a snack does happen,

but finding its way back?

That is probably urban legend.

Back in our living room,

Heidi has become a fully-fledged consummate predator.

Sometimes, when Heidi hunts,

before the attack, she might be camouflaged.

But as she gets ready...

..she'll drop all her camouflage...

..and then there's this ghostly white form.

And then pounce.

While she's a master of her environment...

DAVID ATTENBOROUGH ON TV: ..invigorated by daily sunshine...

..she is also taking part in our lives outside the tank,

adapting to our daily routine with remarkable ease.

We'd come in, we'd turn on the TV,

we'd sit down and a couple of minutes later

she'd move over to the front of the tank, closer to the TV.

She started doing that pretty much every time

we would come into the living room to watch TV,

and so we'd have TV time with the octopus.

I think this is how she would orient herself

if she's actually watching it cos her eyes just moved

so that they're more facing towards the TV.

TV: An oceanic wanderer stops by to be cleaned...

There seems to be, like, very subtle changes,

like slight widening of eyes

and, like, a slightly faster breathing.

TV: ..invigorated by daily sunshine,

marine life flourishes...

But is Heidi really watching TV with Laurel?

The idea isn't as far fetched as it sounds.

Researchers for a long time have used video

to show cuttlefish and octopuses.

And see how they react to it. Are they signalling to one another?

Is there's sort of a language of behaviour?

So it's completely believable that Heidi is watching television.

TV: ..long distances along the reef in order to get here.

But to what extent is she watching us?

Increasingly, we can see just how well Heidi recognises us.

There is good evidence that she is aware of who we are.

So sometimes I take extra measures...

..to be someone else.

EERIE MUSIC

This isn't an octopus horror show.

It's actually based on hard science.

There is plenty of evidence that shows octopus recognise people.

I'm going to weigh Heidi today

and to do that I've got to capture her

so that I can lift her up on the scale

and she might not like that so I'm going to wear a mask.

Well, you see, there's an interesting study

that was done in 2008 that showed that octopuses in aquariums

remember and recognise individual human faces.

The experiment dressed two people in identical uniforms.

One would feed the octopus.

The other would annoy the octopus with a bristly stick.

Within just a week, the octopus would move towards the person

that fed them

and avoid or even squirt the annoying one.

What do you think, Heidi?

Here goes.

And so, when I weigh Heidi,

this just might make it a little easier for her to forgive me

for capturing her and weighing her.

It's harder to tell in the living room experience,

but Laurel is quite convinced that Heidi showed a difference

between the way she reacted to either of us

and visitors to the house.

Recognising people on the other side of the glass

is an unlikely ability for a creature that comes from the ocean.

OK, you've been weighed.

And there is a new dimension being added to this study

of octopus intelligence.

Personality.

Scientists have used the relationship between octopus

and humans in an aquarium setting like this...

Oop! That's the first time that she's ever taken it away from me.

..to demonstrate how individual octopus have their own personality.

And Laurel is certainly convinced about the particular character

of our octopus.

Heidi's definitely a troublemaker.

When we feed her, she grabs onto you...

Heidi!

..and then she jets at you.

That was very wet!

It's just cold. She got it right up my sleeve.

You know, you're trying to pull away with this octopus stuck to your arm

and she's jetting water in your face and it's, you know, she's trying

to get attention and she doesn't want us to leave the room.

There have now been several studies that have looked for signs

of personality in different cephalopods

and typically find that there are individual personalities.

Bringing the octopus into an area of study normally reserved

for animals like chimpanzees and dolphins

is another milestone in the understanding

of octopus intelligence.

And certainly the first time for an invertebrate.

This experience with the octopus in our living room

helps me understand a little bit more about how they

experience the world, but it also highlights a paradox...

..one of the cephalopod mysteries.

Scientists have a model that suggests that

some of the things that go along with intelligence

are longer life spans...

..and complex social lives.

Neither of those things apply to octopuses.

They live short lives and they spend them alone.

The fact that octopuses are solitary seems at odds with how Heidi

can have this kind of intelligent relationship with us at all.

Recently, I've been investigating

a unique discovery in Australia...

That a girl.

..one that suggests octopuses may not always be solitary after all.

This extraordinary discovery happened in 2009

in a small bay not that far from Sydney Harbour.

A diver named Matt Lawrence plunged over the side of his boat

and drifting along just exploring in areas of the bay

that everyone else found were pretty boring.

And in the middle of a silty area,

he came across something very unexpected.

Piles of empty scallop shells.

And in amongst the scallop shells,

about a dozen octopuses had made their homes.

We have nicknamed the site Octopolis,

although it's hardly a city of octopuses.

But an aggregation like this

is unheard of anywhere else in the world.

I'm helping to try and find out what's going on here.

And working with Matt, we're putting some remote cameras down

to get a closer look at the behaviour at this unusual site.

We wanted to capture the natural behaviour

and Matt started putting GoPro down.

You know, one or two GoPros on the site to sort of

film the octopuses when divers weren't around.

And so it's kind of exciting to come back

and track what's going on with the octopuses from moment to moment.

So that's the octopus... Yeah, he's pulling down another camera.

Taking over the camera now.

Oh, he's got the camera.

No wonder we can't keep the cameras alive. They take a beating.

I love it when this happens and then another video

records the octopus vandalising our cameras.

And when the cameras aren't getting pulled apart, they're recording

social interactions that you simply can't see anywhere else.

They appear to signal to one another

and make themselves look really dark and conspicuous and large

when they're approaching

and rather flat and pale when they're retreating.

You see octopuses reaching towards each other.

I wouldn't want to speculate yet what that is,

but they're interacting.

This is pretty new.

So this - this is more of that signalling.

But why does the approaching octopus evict this one and not that one?

I wonder if it's possible

that they're recognising one another, you know. Yeah.

They prefer one animal over another, you know, like a smaller rival male.

That's the high five. Yeah, there it is.

Go over and touch each other and just... Yeah.

Octopolis is sort of a wonderland.

It's just kind of awe-inspiring.

There's octopuses side by side in adjacent dens...

..and that's so surprising for an animal

that we always thought was solitary.

You see octopuses approaching one another, then chasing one another.

We see them wrestle with one another.

It's always fairly spectacular cos it's like watching

two umbrellas have a fight.

HE LAUGHS

What makes Octopolis unique is that this is a spot

where the conditions occur that force...

..social skills upon the octopus.

It's a very exciting find.

It does sort of shake up the cephalopod world a little bit,

to think that octopuses may have to deal with one another

and, in doing so, sort of hone their social skills.

The research has only just begun and we'll need to work out

how these environmental conditions

might create what we thought did not happen...

..octopuses living side by side with one another.

Each new discovery makes a little more sense of how Heidi

can have a relationship like she does with Laurel and me.

Having an octopus in our living room

has enabled us an intimacy not possible in the lab.

And last night I witnessed something I've never seen recorded before.

You know, if she is dreaming, this is a dramatic moment.

You could almost just narrate the body changes and narrate the dream.

So here she's asleep.

She sees a crab and her colour starts to change a little bit.

Then she turns all dark.

Octopuses will do that when they leave the bottom.

This is a camouflage,

like, she's just subdued a crab and now she's, erm...

..going to sit there and eat it

and she doesn't want anyone to notice her.

It's a very unusual behaviour to see the colour come and go

on her mantle like that.

I mean, just to be able to...

..see all the different colour patterns

just flashing one after another.

You don't usually see that when an animal's sleeping,

which really is fascinating.

But, yeah, if she's dreaming,

that's the dream.

The solitary octopus does not fit our theories

of how animal intelligence can evolve.

And yet, it is.

And there is another thing about the octopus

which also contradicts our theories on the development of intelligence.

It is something Laurel and I will soon have to come to terms with

because most octopus live for only a year or two at most.

It is incredible that octopus can become so sophisticated

in such a short time.

There is a connection here

that crosses a divide not just from air into water,

but also across half a billion years of separation.

And it's been a privilege to have a relationship

with such a strange and wonderful creature.