Inside the Animal Mind (2014–…): Season 1, Episode 2 - The Problem Solvers - full transcript

For centuries, we thought animals
were creatures of pure instinct,

with no understanding
of how the world works.

Simple beasts with simple minds.

We thought that only we humans
could actually think,

analyse, reason, use imagination
and solve problems.

But new scientific research
is revealing there is

a small group of animals with
extraordinarily clever minds -

octopus, great apes

and even some birds.

It's a bizarrely diverse group.

But they share a remarkable ability
to analyse



and solve problems
in a very human-like way.

I want to get inside
these animals' minds

and see just how clever they are.

Starting with perhaps the cleverest
of all - the crow family.

How on earth did that crow do that?

I want to push them to the limit,
to find out how

they measure up to other animals
that we think are pretty clever.

All you've got to do
is lift the ball!

I'll discover what makes some
animals capable of brilliant

ingenuity that seems almost human.

It's a sort of Satnav for bees.

I want to uncover why this special
group of animals

have such superb
problem solving minds.

Now, if we can do this,
we might just unlock one of nature's



greatest mysteries - how we
ourselves came to be so clever.

Welcome to a lost world.

The island of New Caledonia.

Lying nearly 1,000 miles east
of Australia, it is a tropical

paradise, bursting with exotic life
found nowhere else on the planet.

I'm here to find one
of these unique animals.

It has an almost legendary status,

thanks to an amazing ability
to solve problems.

The animal that I am looking for
is truly remarkable.

The problem is, it is very,
very difficult to find.

It's cunning. And it's quick.

Agile.

If I'm honest with you, there
could be one right here somewhere,

just looking down at me,
and I've never ever seen one.

Many experts think that these
are the cleverest animals on earth.

I've been told I might see
that intelligence in action

on the island's high mountain roads.

It is this - a crow.

But not just any crow.

This is the New Caledonian crow.

It is not the same species
we find a Britain.

These are jungle birds.

And here,
in isolation on the island,

they have evolved
some remarkable abilities.

This one is holding
a nut in its claw.

It drops it onto the tarmac,

seemingly to crack open
the hard shell.

But in truth, it is what the bird
does next that is really ingenious.

Now, look at this,
this is interesting because,

having broken the nut
open on the road,

these birds are then
carrying it to the Armco here,

where there are small depressions,
man-made cuts, in it.

And they're using these as a vice
to stop the nut from rolling

around whilst they access
the fruit on the inside of it.

Now, that strikes me
as pretty clever.

But the question is, of course,
just how clever are these birds?

To find out, I have come
to visit Dr Alex Taylor

at his field aviary
here on the island.

To study how these birds
solve problems,

he has put a tasty morsel of food
deep in a container.

He is testing whether they can work
out how to reach it

using a variety of objects
he has pleased in the aviary.

But first,
he is trying his puzzle out on me.

Imagine that you are a crow.

Here is your food, in a deep hole.
How would you go about,

with the tools
available to you on this table,

solving this problem?

This is part of it, obviously..

At my disposal, I have a short
stick on a piece of string,

three stones inside the cages...

..and a longer stick
trapped in a box.

Which means, then, that the crow
is going to use this stick...

..to get the stones out of there.
Absolutely.

Next, the crow needs to drop
the stones onto a trap door

to release the long stick.

It is going to need
all three stones.

And then it probably will drop
that one out. Excellent.

And using this long stick, it will
finally be able to reach the food.

This is a tough one.
All right, can I stay in here?

Absolutely, you can sit and watch. We
will see what happens. Come on, then.

Send in your mastermind,
because it is going to need that.

Alex studies wild birds,

which he releases after
three months of research.

This one is nicknamed 007,

and it is about to attempt what Alex
believes is one of the most

complex tests of the animal mind
ever constructed.

The bird is familiar
with the individual objects,

but this is the first time
he has seen them arranged like this.

Eight separate stages that must be
completed in a specific order

if the puzzle is to be solved.

And if the bird succeeds,
it will be a world first.

He takes time to have a look and
then starts with the short stick.

Stage I.

He finds it is too short
to reach the food.

He then sets off to get
the first stone.

But he drops it.

And another. He seems to be stuck.

But then something seems to click.

He deploys the first stone.

And then another.

Got it!

The eighth and final stage.

Success!

Eight individual stages
of one complex puzzle completed.

That was remarkable.

I've never ever
seen anything like it.

Of all of the bird behaviour
I've seen, nothing matches that.

I can hardly believe it.

I'm still just running
that sequence through my mind.

It happened really quickly.

But the immediate question is,
of course,

how on earth did that crow do that?

You see, on the face of it,

the crow's problem-solving abilities
seem mind boggling.

But look close enough
and the natural world is filled with

examples of animals
behaving in clever ways.

The spider spins a web that gets
stronger when it catches prey.

It's precision engineered
to catch flies.

Turtles navigate through thousands
of miles of featureless ocean,

returning every year to the same
beaches to lay their eggs.

It is as if they hold
a nautical map in their heads.

So are the clever crows
really so unusual?

Well, to find out,

I need to investigate
how animals solve problems.

And I am starting back in Britain
with the honeybee,

a small animal that seems to be able
to do something staggeringly clever.

The pollen and nectar that bees eat

is clearly only available
whilst the flowers are in bloom,

so it's there throughout
the spring and the summer.

But the bees have
to get enough of it

so that the hive can make it
through the winter.

And frankly, if that isn't a massive
task, then I don't know what is.

But the bees have
an almost incredible solution.

To see with that is, I have come
to meet Professor Adam Hart.

Hello, Adam. Hi, Chris.

One of his specialisms is
the hidden world of the honeybee.

That is a very intimate view
of the interior of the hive.

Yes, it's like Big Brother for bees.
It is! It's great, isn't it, really?

Adam has set up an infrared camera
to spy on the bees inside the hive.

And we are hoping to see a striking
behaviour that is key to

solving the problem
of gathering enough food.

It is called the waggle dance.

Adam, look at this one. This one
is waggle dancing, isn't it?

Yeah, this is the waggle dance.

You have got this lovely
figure of eight dance,

sometimes getting in the way of
other bees, but generally speaking,

keeping this nice
kind of rhythm going.

The waggle dance
isn't just for show.

This bee has found a good source
of food, and she is performing

a set of very precise movements
to tell the others

exactly where to find it.

And this is all about communicating
the whereabouts of a food source.

Yeah, this is like GPS for bees,
basically.

They are telling other bees not
just that there is food out there,

which is quite a useful signal,
but where that food is.

So they can communicate the direction
and the distance of that nectar.

But how can a dance communicate
where a food source is?

To find out, we need to get
a better view of the horizon.

Super view,
well worth the climb. Yeah.

But what about the mechanics
of this dance, then?

The bee we saw in the hive
was doing this figure of eight,

and that central section was where
she was vibrating her abdomen.

When you think about it,
the only frame of reference bees have

in the hive is gravity, up and down.

The frame of reference they have
out here is the position of the sun,

or more accurately, where the sun
would be if it was projected down

on the horizon,
what is called the azimuth.

From up here, it is easy
to see where the sun lies over

the landscape and where it would be
if it dropped to the horizon.

Now, our dancing bee was waggling
at an angle of five degrees.

So, if this tower were
a massive beehive,

the waggle dance would be telling us
that the nectar is five degrees

from the relative position
of the sun.

That is somewhere in that direction.

All right, that is the direction,
what about the distance?

That's that duration of that central
waggle run, as it is called.

The longer they dance for, the longer
that waggle run goes on for,

the farther away the food is.

So, a very short waggle run,
like we saw down in the hive,

is maybe a couple of kilometres,
whereas they can sometimes

waggle for much longer,
perhaps nine, ten kilometres even.

So, honeybees survive the winter

by using what we'd call mathematics.

They compute angles and distances

and then communicate that
information to their nest mates.

It seems incredibly clever,
but in fact,

it doesn't involve
any thought at all.

You see, the waggle dance is
so important to the survival

of the hive, that it comes built
into the brain of the honeybee.

Every worker bee is born

with the ability to perform
the dance automatically.

In other words, the bees
are acting on instinct -

a set of behaviours

that are so important
to the animal's survival

that they are hard wired.

Think of them as a simple
set of rules that are tattooed

onto its genes by evolution.

It is what makes these bees
do the waggle dance.

The animals have no real
understanding

of what they are doing.

But what about
our New Caledonian crow?

It solved a complex
eight-stage problem.

Is it really possible that the bird
was acting only on instinct,

without any real understanding
of what it was doing?

In short, the answer is no.

Because, unlike bees with their
waggle dance, these birds are not

dependent on solving a multistage
puzzle in order to survive,

for the very simple reason
that you don't find multistage

puzzles like this out there
in the wild. They are not natural.

They are a man-made artefact.

And for that very obvious reason,
there is no chance whatsoever

that these birds could have evolved
an instinct to solve them.

But solve them they do.
So if it isn't instinct, what is it?

To begin to discover what is really
going on in the crow's mind,

I have come to Somerset
to meet Lloyd Buck.

He handles birds for TV and film.

And this is Bran.

He is a raven, one of the largest
members of the crow family,

a group known as the corvids.

What a stunner!

Hold my finger.

Are you going to do it again?

No, he just wants...
Ups, sorry.

You want to hold my finger? No.

You like that camera,
it's the highest point.

Bran is clearly a bird
who knows his own mind.

In fact, it is hard to know
who is in charge.

Myself and my dogs, you know,
I am the pack leader.

What about you and Bran,
who's boss?

Well, I think obviously Ban.

But as far as he is concerned,
I am his mate.

Right. His mate? Yeah.
His partner? His partner.

It is going to be
a long-term relationship

because they're a long-lived bird,
aren't they?

Yeah, in captivity up to 40,
50, even 60 years.

He is going the distance with you.
Yeah.

And they are really time intensive.

You can't just forget him
and leave him in his aviary.

He likes to go out for his fly,
his walk every day.

He wants to see,
he wants to spend time with you.

Cos they are so intelligent.

To keep his demanding bird occupied,

Lloyd likes to set Bran difficult
problems to solve,

like this one.

Lloyd places a piece of food
inside a plastic bottle

and then crushes it.

And you give him a bowl of water.
A bowl of water? Yes.

With the bottle crushed, the food is
trapped behind the restriction.

But this doesn't stop Bran.

First, he adds water.

Next, he spins it,

and the liquid carries the food
past the restriction and out.

That is a clever piece
of problem-solving.

He's got it. He's got it!

Honestly!

What about that?
Now, that is impressive.

The thing is, Lloyd, how long did it
take him to work that out?

Well, presented with
the crushed bottle,

it took him basically an afternoon.

He got frustrated, he couldn't work
it out initially, and he left it.

So we left it with him in his aviary

and we went up
to the house for lunch.

Come back down in the afternoon and,
lo and behold, the food was gone.

But let's not forget
that Bran is a tame raven.

Aren't you a clever boy?
Yes, you are.

It is possible that, in spending
so much time with humans,

he has been able to observe
and copy some of their actions.

You are too clever for your own good
half the time, that is your problem.

So, I'm going
to set Bran a new challenge,

one that he has never seen before.

And this time,

I am going to pit his intelligence
against another animal,

one that we tend to think
is pretty clever,

certainly brighter than birds -

the dog,

or to be more precise, my dogs -
Itchy and Scratchy.

Amongst the dogs, poodles are about
the smartest. Are they? So they say.

Bran, he just finished War And Peace.

I can see how this is going to go.

To make things
even more interesting,

I am also going to put
the same test to Fletcher here,

who is two and a half,

which incidentally is nearly
the same age as Bran.

They are all going to face this -
a puzzle box of my own design.

Here's how it works.

The prize is in the green ball
in the centre.

But to get to it, they firstly have
to pull this drop door down here.

And then,
pull this smaller box out.

And then, remove the lid from that

to get the ball.

Simple, isn't it?

Well, let's find out.

We've given all of our contenders

the chance to familiarise themselves
with parts of the puzzle box.

As usual, Lloyd leaves Bran to it.

Fletcher is also showing
an interest in how it works.

Itch, concentrate.

'Whereas I need to be
a bit more hands-on.'

Now, look, look.

Pull that. What this. Look, watch.

This is the sort of thing my mother
would have done. Look, watch.

That's your lesson over for today.

And now,
the moment of truth has come.

The contenders are about to face
the test proper for the first time.

This is raven versus dog
versus human.

Itchy, solve this.

Solve that. OK?
I'll be back. Solve it.

And that, I'm afraid to say,
is an emphatic win for Bran

and all of his corvid kind.

In truth, my dogs didn't even seem
to realise there was

a problem to solve,
despite all of my training efforts.

And Fletcher, well, he played
around with the box a bit,

but soon seemed to lose interest.

Whilst Bran was so quick that
we will have to use a high-speed

camera just to see how he did it.

So the question is,

why are ravens like Bran able to
solve problems on their own when

other species, including clever dogs
and even young humans, can't.

To find out what abilities
the corvids have

that other animals seem to lack,
I have come to Cambridge

to meet Professor Nikki Clayton.

She is a world expert
on the crow family,

which includes these Eurasian jays.

She sets up experiments to
break down the different abilities

that these birds use
to solve problems.

And she set one of them,
Hoy, a fiendish challenge.

One that wouldn't be
out of place in a physics lesson.

She has dropped some wax worms,
his favourite food,

into a tube of water, out of reach.

So the bird needs to work out
how to raise the water level.

Nikki,
let's see what's going on, then.

Fire up the laptop and see
what he is up to. I will do.

Nikki's birds
have minimal human contact,

so we're watching Hoy
from a safe distance.

Straight away, he starts dropping
stones into the water.

They are quite specific

about what they use, actually,

and how many stones.

They don't put more stones in
than they need.

He is checking the water rise every
time he puts the stone in. Yeah.

He pops up and you can see the eye
looking down. Look at that.

Look at that, the small stone
wasn't going to be enough. No.

There we go, go on.

No, can't quite reach.

You know, Nikki, it is almost

as if he understands the effect
of dropping that stone in.

That's right. He only does this
when there is liquid in the tube.

If there is a worm in the tube
and it's filled with sand,

he doesn't bother. He knows
that it needs to be a liquid

in that tube in order
for the stones to work.

Hoy understands that a sinking
stone will cause the water level

to rise, and this in turn will
allow him to reach the wax worm.

He also knows the same technique
won't work with sand.

And this reveals the first skill
animals need to solve problems -

the ability to understand
the rules of cause and effect.

But I am intrigued to know

how Hoy worked all of this out
in his mind.

He was trained that,
if he drops or knocks a stone

into a tube, he gets a worm.

But in the training apparatus,
the worm comes out the bottom,

not out the top,
and there is no water.

And having learned to associate
stones with tubes to get food,

what he has been able to do is then
to transfer this to a novel problem,

where there is water,

where the worm comes out
a totally different place.

But he has been able to use
his information flexibly

and transfer it to novel problems.

He can join up his knowledge.
Exactly.

So, Hoy was able
to solve this problem,

because he already knew
how to use the stones.

He is able to learn rules
for one situation

and then apply those rules
to a new scenario.

Scientists call this
flexible thinking,

and it is the second skill that
animals need to solve problems.

It is how the New Caledonian crow
solved the multistage problem

and also how Bran made such
short work of my puzzle box.

The birds were thinking flexibly,

using previous experience
to solve new problems.

And it is an ability that seems
sadly missing in my dogs.

Lift the ball, please!
Lift it! Lift it!

Is that why Bran, the raven,
so convincingly trounced my dogs?

It's exactly that, yeah.

So, the dogs can learn
to do something,

but what they can't do is
to transfer it to a novel problem.

Yes, I will be gracious
in defeat on this account,

given the quality of the opposition.

I suspect, if you had been
competing against a pigeon,

you'd have been all right.

They would've even that,
that would've been fine.

So, why are some animals better
at solving problems than others?

It is something
we don't yet fully understand.

But one thing that we do know
is that the answer lies

somewhere in here -

the animal brain itself.

Here are a couple
of very interesting specimens.

This one is the brain of a dog,
in this case a terrier.

And this one here is
the brain of a crow.

And it is immediately apparent
that the dog's brain is about twice

the size of that of the bird.

So, we might imagine,
simplistically, therefore,

that the dog
is a more intelligent animal.

But we already know that the crow

can solve problems
that the dog can't.

So, clearly, there is

more to cleverness
than just the size of the brain.

To investigate what that could be,
I have gathered together

a range of preserved animal brains.

If I arrange them in order
of body size, a pattern emerges.

The bigger the animal,
the bigger the brain.

It seems that the more body
you have, the more brain cells

you need to control it.

In other words, there is

a relationship between the mass of
the body and the mass of the brain.

And roughly speaking,
it is a straight line.

The dog lies pretty much
bang on the line here, which is

where you'd expect it,
given its body size.

And in fact, most animals lie
very close to the line.

But some sit above the line,
like we humans.

Our brains are very large
for our body size.

But what about the crow?

The crow's brain is
also above the line. It is up here,

which means that
its brain is bigger

than we would expect
just given its body size.

In fact, it is about twice the size.

Now, bizarre as it may seem,

the dog's brain is physically
twice the size of the crow's,

but relative to its body size, the
crow's brain is bigger than the dog.

So, perhaps this extra mental power
will allow the crow to

think in a more complicated
and more flexible way than the dog.

And the crow isn't alone in having
a brain twice as big as we'd expect.

In fact, it is in the company
of another animal

known not only for its big brain
but also its cleverness.

It is our nearest relative -
the chimpanzee.

And the chimpanzee holds a special
place in the history of science.

In the 1960s, a young British
scientist, Jane Goodall,

observed chimps doing something that
no-one thought animals capable of -

using tools.

I saw this dark shape hunched
over a termite mound.

He's making arm movements
as though he's sliding it

across the ground
and obviously eating.

But that was all I saw.

And I went up to the heap
and there were

the pieces of grass lying there,
termites moving about the surface.

So I picked up one
of these abandoned tools

and pushed it into the mound,
and the termites bit on.

It was pretty obvious.

Goodall had observed the chimps
using blades of grass as tools

to fish for termites.

It was a discovery
of immense significance,

as her PhD supervisor
immediately realised.

And he sent his famous reply,
"Now we have to redefine man,

"redefine tool or accept
chimpanzees as humans."

Goodall's discovery shattered
our ideas about what sets us

apart from the rest
of the animal kingdom.

We had to accept that animals
were cleverer

than we'd given them credit for.

It also gave researchers
new insights into how

our ancient ancestors might
themselves have solved problems.

And as we have discovered,

chimps are not alone
in being able to use tools.

It is something
that crows can do, too.

To me, what is so important
about using tools is that it reveals

the next crucial ability that
an animal needs to solve problems.

For example, take this stick.

If I want to use this as a tool,

I need to be able to see it
for more than what it is.

More than just a piece of wood,
what a piece of wood might be.

What might it be?

Well, I could sharpen one end and
I could perhaps use it as a spear.

Or I could set fire to it
to generate some heat.

When I'm going through
these thought processes,

there is no doubt that
I am using flexible thinking,

understanding the rules
of cause-and-effect,

but I am also using a type
of thinking which is innovative.

What I am using is imagination.

I'm not just seeing
the world as it is now,

I am seeing the world
how it could be.

And this raises
a very profound question.

Could any other species
of animal have an attribute

so significantly human
as imagination?

To answer this question, I have come
to Austria to meet a rather

inquisitive
and endearing type of bird.

And this time it is not
a member of the crow family.

These are Goffins cockatoos,
a type of parrot.

Big-brained birds
with a very curious nature.

Can I have that back? Thank you.

And I am here to meet
Dr Alice Auersperg,

an expert in these animals.

She is studying their ability
to innovate.

And I am intrigued to know
what that might reveal

about their powers of imagination.

Alice, these birds are very keen
to get to know me, it seems. Yes.

They are especially interested in you
because you are new.

And it is not just me that is new.

So is the entire crew.

And everything that we are wearing.

My watch, in particular, has caught
the attention of Olympia here.

And within minutes,

she has worked out
how to release the clasp.

When they find you,
a human, inside the aviary,

they look for everything that
looks different on your body,

like your shirt buttons
or the shoe laces or your watch.

They go specifically for that

and they stay with it
for a very long time.

You like my shiny watch, don't you?

Alice, I think I've had enough
of being pecked and probed

and pulled by your rather
wonderful cockatoos.

I'd like to see them
in action now, mental action.

Look, the watch is off again.

Come on, I know you can steal my
watch, but what more can you do?

To investigate what is going on
in the minds of these parrots,

Alice created this - the lockbox.

Trapped inside is a tasty nut,

held securely behind this elaborate
locking mechanism.

To see how it opens,

we need to employ the services
of a master safe-cracker.

Or Muppet, as he is perhaps
inappropriately called.

Before we begin, though,
there is the question of eyewear.

If you want to start,
we have to put sunglasses on

because we could cue the birds
with our eye movements.

Can they see where we are looking?
Do they have the ability to do that?

We don't know
whether this species can,

but it has been proven that some can
follow the eye movement of humans.

Better safe than sorry.

We'll forgive fashion for that
and make scientific progress.

And here comes Muppet. He's out.

He is displaying towards you.
A little bit of display.

Yes, he's a boy now.

Very nice, yes. That is
a crest of some distinction.

I had one like that
in the 1980s myself.

But perhaps, Muppet, you could
take your attention to the lock?

Muppet has done this before,

and he delivers... a masterclass.

He quickly removes the pin
and then the screw.

He discards the central bolt
before shifting the locking wheel.

And this releases the final bolt.

Voila!

He has reached the nut inside.

Wow. I should have timed it,
shouldn't I?

But to make sure that Muppet
can't learn the sequence by heart,

Alice can swap the lock sections
around or even remove them entirely.

So now I want to change the way
in which the box works

and set Muppet a new challenge,
one that he has never seen before.

There are five parts. Why don't
we take out the middle bit?

Take out the bolt. Yes, let's.

The upper section is now redundant,

leaving only the lower parts
in operation.

It may look like we have made it
easier, but in fact,

we have created an entirely new
problem with a different solution.

If Muppet can't see this, he will
just repeat what he did before,

and robotically
go for the pin at the top.

But if he can see the new problem

and imagine a new solution,

then he will go
straight for the wheel.

OK, Alice, let's...
let's give him a go.

So now, the moment of truth.

He has gone straight for the wheel.

And then the bar.

And he's in
in less than ten seconds.

Muppet got it right first time.

And that gives us
a crucial insight into his mind.

He must have looked at the problem,
worked it out in his head

and imagined the solution.

That was a hard-earned nut.

So imagination is the third ability
that animals need to solve problems.

It's a skill that seems
to allow them to work out

new solutions in their heads
before putting them into practice.

Up until now, all of the animals
that we've looked at

have used their imagination
to solve problems

which are sat right in front of them

but we humans can do
so much more than that.

We use our imagination
to project into the future,

to see problems coming

and think about how
we are going to solve them.

Until now, we've always thought
of that as a purely human attribute

but what I want to know is can
these clever animals do that too?

There is a common behaviour
in the animal world

that seems to be about planning
for the future.

It's called caching.

It's what squirrels do
in the autumn,

hiding nuts in the ground
so they can be dug up

and eaten over the winter months.

But if caching were an Olympic sport

then the corvids would
be the gold medallists.

Most of them seem to do it, much
to the annoyance of the squirrels.

And this American corvid,
the Clark's nutcracker,

is the caching king.

Researchers have observed
how every year it can store

and remember the location
of thousands of different seeds.

This bird truly is
the master of memory.

But is this just another example

of instinctive behaviour
to survive the winter?

Or is there something
far more complex going on?

It's a question that's greatly
intrigued Professor Nicky Clayton.

She studies Western scrub-jays,

another American corvid
renowned for its caching behaviour.

Nicky wanted to discover
whether they could do more

than just remember where
they buried food in the past.

If they can travel back in their
mind's eye to think about the past,

can they also travel forward in the
mind's eye to think about the future?

Can they imagine the future,
if you like? Can they plan ahead?

To find out, Nicky created
an experiment

based on a very human annoyance -

waking up to find that
breakfast is off the menu.

For six days, the birds
were housed in this aviary,

split into three zones.

In the middle is the dining room,

where the birds were fed
during the day,

and at either end are the bedrooms,
where they were kept at night.

But there is a twist.

Kept overnight in this bedroom,

the birds were served
an early breakfast

but kept overnight in this one,

they got no breakfast and went
hungry until mid-morning.

The birds experienced this daily
routine for almost a week.

We give them three experiences
of waking up in the hungry room

and three experiences of waking up
in the room that serves breakfast.

But the important point
is the birds themselves

didn't know which room they would
end up in on any given day.

But then Nicky changed the test.

She allowed the birds to cache
food in the evening before bedtime.

She placed caching trays in both
the hungry and breakfast rooms.

The question was where would
they choose to store the food?

Nicky wanted to know if the birds
could use their past experience

of the two different rooms
and plan for the future,

namely for breakfast time tomorrow.

The results left no doubt.

What we found is that
the birds cache about five times

as much in the hungry room as
they cache in the breakfast room.

They can imagine what they are going
to need the following morning when

they wake up hungry so they can solve
a problem before it's even happened.

So what this experiment shows is that
the birds can plan for the future.

So the jays' caching behaviour
is far more than mere instinct.

They have a grasp of the past,

but can also anticipate future needs
and, crucially, plan for it.

This skill is very rare
in the animal kingdom

and it's the fourth key ability
needed to solve problems.

It's called mental time travel.

It's the ability to go backwards

and forwards in the mind's eye,
so it's about projecting yourself

in time to remember the past
and to imagine the future.

In humans, mental time travel is a
skill that takes a while to develop.

We're not born with it.

These children are about
to undergo the sweetie challenge.

The task is simple.

Each child is given a sweet.

They are told that,
if they leave it uneaten,

they will get a second one
15 minutes later.

The question is, can they plan for a
future in which they have two sweets

or will the lure of
instant gratification be too much?

It's a skill that children
acquire as they get older.

I think this kind of cognitive
capacity is highly sophisticated.

We know that young children
don't start developing

these kind of skills until
they are at least four years of age.

Clearly,
if you are a bird or a human,

it's no bad thing
to be a mental time traveller.

When we look at the world's
cleverest creatures,

we see a group of very
different animals -

the great apes, the corvids,
the parrots.

And yet, they all think
a little bit like we do.

They have the ability
to understand cause and effect

and can utilise this understanding
in new and novel situations.

They can also implement imagination
and this allows them

to think ahead,
to plan in the future.

Now, together,
these abilities allow them

something which is incredibly
rare in the animal world.

It's the power to reason,
the power to solve problems.

But of course, it also
raises another question -

what is so special
about this group of animals?

What could they possibly
have in common?

To answer that, I want to look
in a very different environment.

'Here on the island
of Bimini in the Bahamas,

'I'm seeking out
an elusive creature.'

It's a creature that's as different
from a bird or a chimp

as it's possible to be.

Now, this beautiful animal
is a common octopus.

Don't worry too much
about it being out of water.

They will frequently move over land,
between rock pools like these,

so he will be OK for a while.

It lives in a world
which is very alien to us -

rock pools and rocky caverns
on the coast here.

And as a consequence,
its anatomy is very different.

Inside this animal,
there are three hearts

but perhaps the most profound
difference of all is its brain.

The octopus brain is
spread around the body.

Each leg even has its own
mini brain to control it.

It's nothing like the
one-stop shop that we have.

But what's extraordinary is this
animal has problem-solving abilities

similar to those
of the great apes...

..the parrots and the crows.

This is a veined octopus
just off the coast of Indonesia.

In this environment,
it is very exposed to predators

but it has worked out a solution.

It's found a discarded coconut shell

and despite being
an unfamiliar object,

the octopus sees its potential.

It tries it on for size before
picking it up and carrying it away.

Now, when a threat appears,
it has a place to hide

and it can retreat
inside its coconut sanctuary.

This is an example
of an octopus using tools.

It seems to be using
all the key abilities we've seen

in the cleverest animals on land.

So what can the octopus,
with its strange brain,

possibly have in common
with apes and birds?

When animals are very different,

then the similarities can actually
be a lot easier to see

and we have to look beyond the fact
that birds can fly,

apes have dextrous hands

or that octopus actually
move on their eight arms.

We have to not concentrate so much

on the physical nature
of these animals,

but look at the things
that have made them what they are.

And when we do that,
a pattern emerges.

For instance, all these animals
eat a wide variety of foods

and need to master different
techniques in order to obtain them.

They crack, they pluck
and they hunt.

Our own omnivorous diet
isn't too different.

And all these animals tend
to be both predator and prey.

Which is also true
of our own ancient ancestors

on the plains of Africa,
millions of years ago.

So it seems that, to live flexibly,

you have to be able
to think flexibly.

But there is something else
that the supreme problem solvers -

the apes, the corvids
and the parrots - share.

They live in groups.

So whether they walk, swim or fly,

the supreme problem solvers
of the animal kingdom are not

so different from one another
as we might have first imagined

and, although their minds
are not as potent as ours,

their powers to reason

and even exercise imagination
are quite remarkable.

But then, up until now, we have been
looking at them as individuals.

What I want to understand next
is do they have the capacity,

like humans, to actually share
the solutions to problems?

In short, if they come up with
a good idea, can they pass it on?

On New Caledonia,
the crows have lots of good ideas.

They are precision tool makers.

This one is in the process
of doing something

we would normally expect
only of humans.

It's crafting a hook that it's
going to use to catch its prey.

It's an astounding behaviour.

Dr Alex Taylor and his colleagues
are now investigating whether

these birds are able to share their
tool-making skills with each other.

That is amazing.

So they have sculpted
a little hook out of another piece

of the twig that formerly
would have run out here.

It's beautiful. It's almost like
a primitive human tool, isn't it?

It does appear that way.

We talk about the imposition
of three-dimensional form

onto a natural object.

That's something that humans
have only been able to do

for the last 100,000
or 200,000 years

and here we have a crow
doing something very similar.

And you can see how that can be
useful because a crow would be able

to insert that into a hole
and quite literally use that hook

to draw out a grub
or anything else it was after.

Absolutely.

Made by a bird! That is absolutely
brilliant! Absolutely brilliant!

And of even more interest
to Alex are these -

intricately cut tools from
the leaves of the pandanus tree.

Unlike the hooks,

there are distantly different types
of pandanus tool.

They differ in complexity,

ranging from a simple leaf fragment
to multistep implements like these.

And across the island,

different groups of crows use
different types of these tools.

In the south, many different
fragments are found

that, as we move north,

the crows start to favour more
complex, multi-staged tools.

It means the different
groups of crows

have their own ways of doing things.

In human society,
we would call this culture.

What we are seeing across
New Caledonia is populations

of crows that appear
to have traditions

of making single-step tools
or two-step or three-step tools

and these traditions are persisting
over 10 or 15 years at least,

that's as much... how long
we've been studying them for

and we believe they have been
there for a lot longer.

It appears there's some
kind of transmission of tool design

across the population.

A rare and fascinating glimpse
of how this might happen

has been captured on camera.

Here an adult bird is using a stick
to probe for grubs inside a log.

A youngster stands by, watching,

as the adult seems to demonstrate
the right way to use the tool.

And when the adult departs,

she leaves behind the stick
in the hole.

The youngster can
now have a go itself.

Although this one has some way to go

before it becomes an expert
like its parents.

It seems as though one way ideas can
travel through the crow population

is via family groups,
the social circle.

But Alex's research suggests
something even more extraordinary -

that, with each new generation,
the ideas don't stand still

but are honed and improved.

When we talk about this,
we talk about the ratchet effect,

which is this idea
that it's a really good idea

to be able to copy each other
and, as a group, you can end up

being able to build better
and better tools.

Obviously, we don't invent the wheel
every generation ourselves,

we make it better and better.

Potentially, this is what's
going on here with the crows.

There's no concrete evidence
that any animal species

is able to actually show this
ratcheting up of their technology,

to make it more
and more sophisticated.

So it would just be
crows and humans?

No chimpanzees? Nothing?
At the moment, no.

It's something we think
is unique to humans,

but maybe is going on
with these crows as well.

The New Caledonian crow has only
been studied since the early 1990s.

In that short period, scientists
have revealed an animal mind

that rivals the problem-solving
skills of our closest cousin,

the chimpanzee.

And for me,
the really exciting thing

is that we are just beginning
to understand these animals.

Who knows what else
they might be capable of?

On this journey,
I've come to an understanding

about what makes some animals
cleverer than others

and even where that cleverness
actually comes from.

And whilst we might reign supreme
across the animal kingdom

when it comes to complex thought,
we are certainly not alone.

It also seems
we may not hold a monopoly

on the ability to share ideas
and learn from one another.

So perhaps it's no surprise at all

that the most intelligent animals
on our planet are the social ones.

And next time I'll be investigating

the minds of some very
social animals.

I'll uncover the secrets
of dolphin society,

discover how chimps deceive
one another

and learn that we are not alone
in mourning our dead.