Nova (1974–…): Season 41, Episode 8 - Inside Animal Minds: Bird Genius - full transcript

From PBS - Today, researchers are discovering that some creatures have mastered skills purportedly restricted to humans. Many are bird brains. Meet a cockatoo with a talent for picking locks; a wild crow on a mission to solve an eight-step puzzle; and a tame raven who can solve a puzzle box so quickly that his performance has to be captured with high-speed photography. Are these skills really evidence of high intelligence or just parlor tricks, the result of training and instinct? To find out, NOVA tests the limits of some of the planet's brainiest animals, searching for the secrets of a problem-solving mind.

What are they thinking?

What really makes them tick?

Oh, look at that face!

Is there any way to get inside
the animal mind?

What I really want to know

is what is it like
to be an animal,

what's it like to be
inside their head

and what are the problems
they have to solve,

and how do they think,
and are they like us

or are they like something
totally different?

They have some amazing abilities



Is it instinct

training

or something else?

Cutting-edge animal science
reveals new answers,

getting inside their heads
in ways never before possible

Without proper training,

the dogs would just run scared
from the MRI

We put different species
to the test

in search of the roots
of animal intelligence

Who are the best
problem solvers?

Who wins the battle
of the super senses?

Dive deep into
the animal experience

to explore their language

relationships



even emotions

If you start giving
one of them grapes,

which are far better
than cucumber,

then the one who gets cucumber
becomes very upset

Are they more like us
than we ever thought possible?

Having a sense of self

might go with complex
understanding of others

On this episode

How smart is this bird brain?

Imagine that you're a crow

Here's your food in a deep hole

How would you go about
solving this problem?

They use tools

and pick locks

But what happens
in a brainy smackdown

between this bird
and man's best friend?

How did a creature

with such a tiny brain
get so smart?

A crow's brain in relative terms

is as big as that
of a chimpanzee

Why is it that that animal
can solve those problems?

Why would we observe that level
of flexibility

in that species of bird

that we don't observe
in another species?

"Inside Animal Minds:
Bird Genius,"

right now on NOVA.

We've always admired birds
for their grace and beauty

But we don't usually think
of them as incredibly bright

After all, isn't "bird-brained"

the very essence of stupidity?

But now, scientists
are discovering bird brains

that put most other animals
to shame

That's no surprise to Lloyd Buck

There it is

Lloyd handles birds
for TV and film,

and one of his stars
is a raven named Bran

There's a good boy

Well this is Bran,
and he's a three-year-old raven

We've had him since he was
about ten days old,

so he's what you call
complete social imprint

on humans, but he's
particularly bonded with me

We share a very, very close bond

Captive ravens can live
60 years or more,

so Lloyd and Bran are in
for a long-term relationship

Are you going to do it again?

But right now,
Bran wants to explore

his relationship with the camera

Going to hold finger?

No

Sorry, he likes your camera

It's the highest point

That's a good boy

To keep his demanding bird
occupied,

Lloyd gives Bran puzzles
to solve on his own

Here's a problem
Lloyd first presented to Bran

a few months ago in his aviary,
where he has a bird bath

Lloyd places a piece of food
inside a plastic bottle

and crushes it
so the food is trapped

But this doesn't stop Bran

First, he adds water

Next, he swishes it around

And the liquid carries the food
past the restriction and out

That is a clever
piece of problem solving

Good boy

You're clever

Bran wasn't taught
to solve this problem

Lloyd just gave him
the challenge one afternoon

and left Bran alone to try
to find a solution himself

So we've presented him
with that problem,

and through his own intelligence
and problem solving abilities

he worked out
to use his own water,

what he had around him
to his advantage,

which I think shows
a lot of intelligence

People who've observed crows
and ravens closely have said

that they are pretty clever
creatures

But in recent years,

new experiments
are probing deeper,

trying to solve the secrets
of their problem-solving brains

And beyond birds,
researchers are discovering

more and more animals
doing things

we once thought
were strictly human

So how smart
are these creatures?

Inside their minds,
are they analyzing

and solving problems
the way we do?

Or are these animals' skills
more like parlor tricks,

the result of training
and fueled by instinct?

What I really want to know

is what is it like
to be an animal,

what's it like to be
inside their head

and what are the problems
they have to solve,

and how do they think,
and are they like us

or are they like
something totally different?

From the beginning,
one way that humans

have solved problems has been
by using tools

It was once considered proof
of our superior intellect

But it turns out,
all kinds of animals use tools

Even an octopus...

A close relative to clams
and oysters... can do it

Off the coast of Indonesia,
this veined octopus

finds a discarded coconut shell
on the sea floor

and uses it to protect itself
from predators

First it crawls
inside the hard shell

Then it uses its eight arms
to carry it off

People used to think that
tool use was unique to humans,

but of course
that has never been the case

Ever since Darwin,

we've known that animals
have been using tools

But what's really unique
is tool manufacturing

Humans, of course, manufacture
a huge array of tools

for different purposes

And for centuries,
we thought that only humans

were smart enough to make a tool

All that changed in the 1960s,
when Jane Goodall

discovered chimpanzees
breaking all the rules

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

Not only did Goodall see chimps
using blades of grass as tools

to fish for termites,
but she also witnessed them

making tools by stripping leaves
off twigs

Her research supervisor
was amazed

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 smarter than we'd
given them credit for

She created basically
an environment

that we have to think
about their minds,

and we have to recognize
the fact that in many cases,

animals may have abilities

that we thought
were the province of humans

Today, animals with impressive
skills and brainpower

can be found on land

and sea

and air

And some of the most surprising
can be found here:

New Caledonia

Lying nearly 1,000 miles
east of Australia,

this remote Pacific island
is home to an animal

hailed by some as one
of the smartest on Earth,

in part because along
with humans and chimps,

it is an expert tool maker

Meet the New Caledonian Crow

In the wild,
the crows shape hooked sticks

and use them to spear grubs

But today, biologist Alex Taylor
is designing an experiment

to see if crows can use tools
in new ways to solve problems

Alex works with wild birds,

which he releases
after a three month period

This one is nicknamed 007

007's mission is to get
a tasty piece of meat

out of this narrow plastic box

What we have here

is our deep hole

This has got some meat in

The meat is positioned
so deep in the narrow box,

it's out of reach of 007's beak

But Alex has placed a number
of other objects nearby

The question is, can 007 use
them to get the piece of meat?

Imagine that you're a crow

Here's your food in a deep hole

How would you go about,
with the tools available to you

on this table,
solving this problem?

007's toolkit includes
a short stick

hanging on a piece of string,

three stones inside wooden cages

and a longer stick
trapped in a plastic box

First, the crow must use the
short stick to get the stones

And then use all three stones
to get the long stick

And now the crows can take this

and probe it into the hole
and roll...

Much better than I can...
The food out of the hole

and get themselves
a nice tasty reward

It's a complicated task

007 is familiar with the
individual pieces of the puzzle

He's done each of them
separately for a treat

For example, he's used stones
to get a piece of meat

out of the trap door box

But this is the first time
he's seen the tools

arranged like this:

eight separate stages
that must be completed

in a particular order
if the puzzle is to be solved

At first, he takes time
to check things out

Then goes for the little stick

He tries to use it
to reach the meat,

but it's too short

So he sets off
to get the first stone

Got it!

But he doesn't seem to know
what to do with it

He gets another stone

But he appears to be stuck

Now, something seems to click

He puts the first stone
into the box

where the long stick is trapped

Then the second stone

And returns to collect
the last one

He's got the long stick
and goes right for the meat

The final stage

Success

007 successfully executed
all eight tasks

to collect the out of reach
treat

How did he do it?

One of the striking things
is how skillfully 007 employs

a number of different tools
to get what he wants

That's because New Caledonian
crows are born tool-users

Auguste von Bayern
is an expert in corvids,

the family of birds
that includes crows, ravens,

jays and rooks like this one

New Caledonian crows
have evolved

with several physical features
that allow them

to more easily manipulate
objects...

Particularly sticks

New Caledonian crows are famous
for their very straight beak,

and it turns out this is
an adaptation to their tool use

This is really striking

because other corvids
have curvy beaks

You can see that very well
in the rook

The straight beak
allows the New Caledonian crow

to hold tools in front of it,
in its line of vision

But that's not all

New Caledonian crows have eyes
set closer together

than other birds,

which means there is
a significant overlap

of what their two eyes can see

This helps the crow to focus
on the end of a tool

They can see the working end
of the tool extremely well

and look into the narrow holes
and see what they're doing

Tools aren't a recent discovery
for the New Caledonian crow

They've been using them
for so long,

they have physically adapted
to tool use

No other adaptation like this
has been described

in any other tool-using animal,
so this is fairly special

So the eight stage puzzle
didn't pose

too much of a physical challenge
for the crow

But how did it figure out

which order to perform
the tasks?

What was going on in its mind?

Did it imagine the entire
solution to the puzzle?

Was it just using trial
and error step-by-step?

Was it conditioned
by its training

on the individual parts?

Or is the answer
somewhere in between?

Can animals essentially imagine
or infer or reason

about how to solve a problem
they've never seen before

and come up with a solution
that then they can act on?

On the face of it,

the crow's abilities
seem impressive

But look closely enough,
and the natural world

is filled with examples

of animals behaving
in what look like clever ways

The spider spins a web
that is precision-engineered

to catch flies

Turtles navigate
through thousands of miles

of featureless ocean,

returning to the same beaches
every year to lay eggs

It's as if they hold
a nautical map in their heads

So are the crows
really so unusual?

To begin to find out,

we need to delve
into the animal mind

and see how other animals
solve problems

Like the honeybee:

a small animal that is able
to do something

that seems incredibly smart

Insect expert Adam Hart
is interested in how bees

solve a very difficult problem

Inside a typical hive, there are
about 40,000 honeybees

Every day,
they face the challenge

of having to feed themselves

The pollen and nectar
that bees eat

is only available
when flowers are in bloom

So in spring and summer,
the bees have to collect

enough of it to eat
and enough to turn into honey

to keep the hive going
through the winter

Sometimes they can fly
more than six kilometers

to get enough
nectar and pollen back,

because they need a plentiful
and vast supply

Finding enough food is a huge
logistical challenge,

but the bees have an almost
incredible solution

Adam has set up
an observation hive

It's completely dark inside,

so infrared cameras
reveal what's going on

Initially, it looks very chaotic

It looks like bees
are everywhere

But you can see some vibrations
going on and some movements

that are actually part
of a very sophisticated

communication system

The bees perform
a striking behavior

that's key
to solving the problem

of gathering enough food

It's called the waggle dance

The waggle dance
is a very sophisticated way

of directing foragers towards
nectar in the environment

So it's telling them where to go

This bee has found
a good source of food

and she's performing a set
of very precise movements

to tell the others
exactly where to find it

It tells them the direction
and the distance of the nectar

The best way to understand how
the waggle dance actually works

is to get up high,

because then you can get
a view of the landscape

in which the bees are operating

The meaning of the waggle dance

was first proposed in the 1940s

But it wasn't proven until 2005,

when scientists were able
to track bees

using radar technology

This church tower gives Adam
a bee's eye view

of the countryside

From up here, it's easy to see

where the sun lies
over the landscape,

and where it would be
if it were on the horizon

One of the dancing bees
in the hive was waggling

at an angle of five degrees
from the vertical line

So if this tower
were a massive bee hive,

the waggle dance would be
telling us that the nectar

is five degrees
from the relative position

of the sun

But they can also
advertise distance

because the duration
of that waggle run,

that central component,
tells the bees

how far away the resource is

The closer it is,
the shorter the waggle run

So honeybees survive the winter
by using what we call geometry

They compute angles
and distances

and then transmit that
information to their hive-mates

How can a small insect
with such a tiny brain

do something
so incredibly sophisticated?

It's instinct

It's hardwired
into the bee's brain

And we know that

because if you take
older bees out of the hive,

the younger bees who have never
been exposed to a waggle dance

will spontaneously
begin waggle-dancing

and doing this behavior

It's absolutely built-in,
it's instinctive

This is an evolved behavior,
an evolved instinct,

that leads to high survival
of honeybees

Instinctive behavior

is often crucial
to the survival of a species

But the animals don't need
to have any real understanding

of what they're doing

Animal behavior often appears
very complex,

but there might be
very simple rules

underlying the pattern
that we see

So what about
the New Caledonian crow?

Researchers have found that

like bees
and their waggle-dance,

young crows will instinctively
pick up sticks with their beaks

even if they've never seen
another crow do it

But was 007 acting
just on instinct

when he solved
the eight-stage problem?

Nicky Clayton,

one of the world's
leading experts on corvids,

is convinced that
it's something more

The behavior of the
New Caledonian crow

when it's solving
one of these problems

is far more complex
than anything

that would be solved
by an instinctive mechanism

So if it isn't pure instinct,
what is it?

Scientists disagree
about what exactly is going on

in the mind of a crow like 007

or a raven like Bran
when they're solving problems

Some researchers think
the animals

are instinctive tool-users

and can be conditioned
by training

to use them in ways
that just appear clever

But others believe that animals
show real smarts

when they tackle novel problems
that they've never seen before

To demonstrate this,

we set up a little competition
to solve another puzzle

between Lloyd Buck's raven Bran

and an animal a lot of people
think of as pretty smart:

a dog

Actually, two dogs:

French poodles named
Itchy and Scratchy

It's a specially designed
puzzle box

Inside the blue ball,
there's a tasty snack

that each contestant
likes to eat:

rat meat for Bran,

a doggy treat
for Itchy and Scratchy

The challenge is to remove
the blue ball

from the two plastic boxes

First, the contenders
have the chance

to familiarize themselves
with parts of the puzzle box

As usual, Lloyd leaves Bran
to investigate on his own

Good boy

The dogs are introduced
to the components

by their owner

Itchy, concentrate, look

The outer box has a hinged door
that can be opened

by pulling on a pink ball
tied to the door with a string

Another ball and string
can then be used

to pull out the inner box

Then a third ball and string
must be pulled

to remove the lid,

freeing the blue ball
which holds the treat

And now, the moment has come

The animals are about to face
the test for the first time

This is dog versus raven

Itchy, solve this

Solve that, I'll be back

Solve it

Bran gets the tasty treat

The dogs didn't seem
to even realize

there was problem there
to solve,

despite some guidance

But Bran was so quick,
we have to use

a high-speed camera
just to see how he did it

An emphatic win for Bran
and his corvid kind

It's clear that corvids
like these have a knack

for solving problems
that involve getting food

out of hard-to-get places,

even in situations
they've never seen before

While dogs are very good
at paying attention to humans

and can be trained
to carry out complicated tasks,

they're not so good
at tackling novel problems

like this one,

despite the fact
that there's food involved

Why is it that that animal
can solve those problems?

Why would we observe
that level of flexibility

in that species of bird

that we don't observe
in another species?

Here at Cambridge University
in England,

Nicky Clayton is trying
to find out

how the corvid mind works

She sets up experiments
to break down

the different abilities
these birds use

to solve problems

And she gives one of them...

A Eurasian jay named Hoy...
A particular challenge

First, he's presented
with a plastic tube

When he puts a rock
in at the top,

a tasty food reward... a worm...
Comes out at the bottom

When he's got the hang of that,
Nicky gives him a new test

She drops some worms...
His favorite food...

Into a tube of water
out of reach,

and leaves a pile of stones
next to it

There's a delicious, tasty worm
floating on the top

At the moment, it's out of reach

Then, Hoy picks up a stone
and drops it in the tube

Does Hoy actually understand
that a sinking stone

will cause the water level
to rise,

and this in turn will allow him
to reach the worm?

When Nicky gives him
the same tube,

but this time with the worm
sitting on sand instead of water

Hoy does not use the stones

Nicky believes he understands
the difference

He seems to understand
that it's only any good

if there's a liquid in the tube

It's a very useful skill

when it comes
to solving problems:

the ability to make a connection
between cause... the stone...

And effect...
The rising water level

Cause and effect is the ability

to understand what causes what,

why did a particular
event occur,

if you can identify that
so you know what causes it

And that means as humans,
we're able to recreate

that same cause
to get that same effect,

and that's a really
powerful skill

To figure out step one,
putting stones in the tube,

Hoy took the knowledge
from the training task

and transferred it
to the new one

This is another skill
many corvids display

when tackling problems:

the ability to think flexibly,
to use information learned

in one situation
and apply it to another

Flexible thinking is the ability
to transfer information,

knowledge, from one problem
to a brand new problem

So it's applying knowledge
to new contexts

And this is how
the New Caledonian crow

solved the multistage problem

New Caledonian crows
need flexibility

in their environment they
evolved in to process food,

and to be able to get access
to food in new ways using tools

in settings they may not
have encountered before

This also explains how Bran
quickly solved the puzzle box

The birds were thinking
flexibly, an ability

that seems to be missing in dogs

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

It's something we don't
yet fully understand

But one thing we do know is
that the answer lies

somewhere in here

The animal brain itself

So what you can see here
are a couple of pickled brains

That's a crow brain
and that's a dog brain

The dog's brain is clearly
bigger than the crow's brain

and so you might expect dogs
to be smarter than crows

But we've seen
that's not the case

Crows can solve complex
problems that dogs can't

So there must be more to
cleverness than just brain size

To explore what that might be,
Nicky's gathered a range

of preserved
animal brains collected

by Victorian naturalists

The first thing we see is
that the brains

are all different sizes

But when they're arranged
in order of the size

of the animal they come from,
we see a pattern

So, the bigger the body,
the bigger the brain

And it seems that,
in fact, the bigger the body,

the more brain you need
to control it

Most of the time, there's
a straight-line relationship

between the mass of the body
and the mass of the brain

Larger animals need more
extensive nervous systems

to coordinate
their bigger bodies

Their sense organs
are also bigger,

so they require greater amounts
of neural tissue

to process all the extra
information being gathered

You can calculate how big you'd
expect any animal's brain to be

by its body size

This is where the dog occurs

It's bang on the line,
just what you'd expect

given its body size

Most animals are more or less
on the line, but not all

Some animals sit above the line,
as we humans do

Our brains are very large
for our body mass

The difference between expected
brain size and actual brain size

is known as the encephalization
quotient, or EQ

The further above the line,
the greater the EQ

So where is the crow?

The crow's brain is
above the line,

so that means that it's
got a much bigger brain

than you'd expect
for its body size

In fact, it's twice as big

As bizarre as it may seem,
while the dog's brain is

about ten times as big as the
crow's brain in absolute size,

in relative terms, the crow's
brain is twice as big

as the dog's

So maybe evolution
has really forced them

to invest more in their brains

and that's partly
what makes them so flexible

And the crow isn't alone

in having a brain twice as big
as we'd expect

The crow is the same
distance above the line

as that of the chimpanzee

In other words,

a crow's brain,
in relative terms,

is as big as that
of a chimpanzee

These big-brained animals share
some impressive skills,

including the manufacture
of tools

This highlights another key
concept in problem solving

The ability to innovate

Alice Auersperg works

with an endearing
and inquisitive type of bird,

the Goffin's Cockatoo,
an Asian parrot

Like the crows,
these are big-brained birds,

but with a playful personality

Alice studies these animals
to find out how adept they are

at innovating

My Goffin Cockatoos
are very, very curious

So when they see an object,
for example, let's say a human,

they go for shoelaces,
watches, glasses

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

Alice created this, the lock box

Trapped inside is
a tasty nut securely held

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's known

Before Muppet begins,

any humans in the room have
to put sunglasses on

This is so the bird can't take
any cues from eye movement

Muppet has done this before

He wasn't taught by Alice,
but watched other birds do it,

and now he delivers a master
class in operating the lock box

He quickly removes the pin

Then the screw

He easily discards
the central bolt,

which in turn allows him
to shift the locking wheel

This then releases
the final bolt

And, voilà,
he's reached the nut inside

Now for the second part of the
experiment, the transfer test

After the cockatoos
had cracked the problem,

we tested whether they were only
running through a sequence

of learned behaviors or whether
they could react flexibly

to changes

To make sure Muppet hasn't
just learned the sequence

by heart, Alice can change
the lock sections around

or even remove them entirely

This creates a completely new
challenge for Muppet

Alice removes
the middle part, the bolt

With the bolt gone, the upper
section is now redundant,

leaving only the lower parts
in operation

The question is whether Muppet
can see the new problem

and work out a new solution

If he doesn't understand
how the locks work,

he'll repeat what he did before
and go for the pin at the top

If he recognizes
that the problem has changed

and that removing the pin
at the top is unnecessary,

he'll go right for the wheel

So now, the moment of truth

Muppet ignores the pin
and screw at the top

and goes straight for the wheel

And then, the bolt

And he's in,
in less than ten seconds

This is the first time Muppet's
seen this configuration

and he gets it right

Alice believes this provides
crucial insight into his mind

The birds in the transfer test
spontaneously reacted

to novel changes that they had
never encountered before

that indicates that this cannot
be trial-and-error learning

Since Muppet went straight
for the middle bolt,

it seems he has
some understanding

of how the lock system works

and can apply it
to different problems

He's one of a small group
of animals that can do this

But the problems are right
in front of them

We humans can take problem
solving a step further

We use our minds
to project into the future

And anticipate problems
before they even happen,

and plan to avoid them

It's something we long
thought only humans could do

But can these
clever animals do it, too?

There's a common behavior
in the animal world

which seems to be all
about planning for the future

It's called caching

It's what squirrels
do in autumn,

hiding nuts in the ground
so they can be dug up

and eaten in the winter

Here on the island of Santa Cruz
off the coast of California

lives a bird that has caching
down to a fine art...

The Island Scrub Jay,
another clever corvid

Mario Pesendorfer is in the
middle of a three-year project

to find out more about them

We're looking at habitat called
oak chaparral,

which is home
to the Island Scrub Jay,

and it's dominated
by these scrub oaks

And this is where the island
scrub jays get their acorns

Scrub jays love acorns

But they aren't available
all year round

On Santa Cruz,
boom time comes in autumn

when the oak trees
drop their acorns

This is when the jays get busy

They pick up the acorns and they
fly with them somewhere

and they hide them in the ground

And that's what
we call scatter hoarding

because they scatter their
hoards all over the place

So they store their food for the
winter all over their territory

and then they come and get it
back when it's raining and cold

and there's nothing else
that they can eat

Mario uses GPS
to keep an inventory

of the acorns the jays put
away in hidden caches

There's quite a few
to keep track of

In fact, each jay caches
thousands of acorns

They take out 5,000
to 6,000 acorns a year

out into this landscape
and hide them all over

in little cracks and crevices
and below other plants

But of all of these,
how many can they find again?

Of the 6,000 acorns
that they cache,

we think that they recover
about a third

These scrub jays aren't the
only corvids that cache food

Another American corvid,
the Clark's nutcracker,

caches seeds
in even greater numbers

It remembers up to 10,000
caching locations a year

quite accurately,
and they are often spaced

up to 20 kilometers
or 30 kilometers apart

The ability to remember
thousands of locations

is impressive enough

But these corvids go further

They have a sense of when they
buried each piece of food

and know when they need
to retrieve it

They know that if they hide
certain kinds of food,

they have a time frame,

that they need to get worms,
for example, faster than nuts

because worms will rot

So they have to be faster
about getting the worms

So it suggests they have
a more sophisticated idea

about the way that they are
hiding their food

But how sophisticated?

Could these birds really
have a sense of time?

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

She studies Western Scrub-Jays,

close relatives
of the Santa Cruz birds,

also renowned
for their caching behavior

Nicky wants to discover
whether they can do more

than just remember where
and when they've 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 plan ahead?

To find out, Nicky
creates an experiment

based on a very human
annoyance...

Waking up to find breakfast
is off the menu

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

split into three zones

In the middle is the dining room
where the birds are fed

during the day

And at either end
are the bedrooms

where they are kept at night

But there's a twist

Kept overnight in this bedroom
on the right,

the birds are served
an early breakfast

But kept overnight
in this room on the left,

they get no breakfast, and they
go hungry till mid-morning

The birds experience this daily
routine for almost a week

So we give them three lots
of experiences

of waking up in the hungry room,
and three lots of experiences

of waking up in the room
that serves breakfast

But the important point is that
the birds themselves didn't know

which room they'd end
up in on any given day

But then, Nicky starts allowing
the birds to cache food

She places trays full
of sand in both the hungry

and breakfast rooms

The birds can use these
to bury dead grubs in

The question is, where will
they choose to store the food?

Nicky wants to know if the birds
can use their experience

of the hungry and breakfast
rooms and plan for the future

For Nicky, the results are clear

The birds cache about five times
as much in the hungry room

as they cache
in the breakfast room

The scrub jays store five times
more grubs in the room

where no breakfast
is served than in the room

where they are well-fed

They can imagine what they're
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

Nicky believes the jays'
caching behavior is far more

than mere instinct

She thinks they
have a grasp of the past

but can also
anticipate future need

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

It's a skill that is very
important to us humans

We're able to remember
what we were doing yesterday,

we're able to plan
what we want to do tomorrow

And this ability to mentally
travel in time

has really allowed humans
to take over the world

in a way that no other
animal species has

In humans, mental time travel
is not a skill we're born with

It takes a while to develop

To demonstrate this,
these children are about

to undergo the candy challenge

The task is simple

Each child is given a piece
of candy

They're told
if they leave it uneaten,

then they'll get a second
one 15 minutes later

The question is
whether they'll imagine

their future selves happy
with two candies,

or will the lure of instant
gratification be too much

It's a skill that some are
clearly better at than others

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're at least
four years of age

So whether you're
a bird or a human,

mastering mental time travel
has its advantages

To solve new problems,
it really helps

if you can understand
cause and effect,

think flexibly,
apply what you've learned

to new situations,
and plan into the future

It's a rare skill set,
and the animals that have it

are a diverse group...

From the chimps
to the parrots to the corvids

So what's special
about these animals?

What could they possibly
have in common?

On the face of it, of course,

crows and chimpanzees
are very different

The key is not the physical
nature of these animals,

but the conditions that have
made them what they are

There's some common pressure,
there's something common

about the environments
or the experience

of those animals through their
life that's pushing them

to become more intelligent

These animals live in
challenging environments

Sometimes their favorite foods
aren't readily available

They have to be flexible
in order to survive

So there is definitely a
relationship between having

to find food in complicated
ways, having to deal with new,

ever-changing environments,
and those things

that we would put under
the definition of intelligence

Having a varied diet
and being flexible

in their search for food seems
to have increased their chance

for success

But there's something else
that chimps, crows

and parrots seem to share

They live in groups

When we see animals that can
solve more complex problems

than others, one of the threads
that people are excited about

is maybe it's something
about the complexity

of their social organization...

That animals that have
to deal with social complexity

are the same animals, the same
species, that are solving

many of these difficult problems

Whether they walk or fly, some
of the best problem-solvers

in the animal kingdom may
not be quite so different

from one another
as they first appear

Researchers are trying
to figure out

exactly why complex
social lives might create

better problem solvers

Could one explanation be that
the animals share knowledge?

If they come up with a good
idea, can they pass it on?

New Caledonian crows
have lots of good ideas

They are precision tool makers

This one is in the process
of crafting something

we'd normally expect
only of humans

It's making a hook
that it will use to catch prey

Alex Taylor is investigating
whether these birds are able

to share their tool making
skills with each other

What the crows have done is,
they've rounded off the end

and they've actually carved out
a tip onto the end of the tool

This tool works
as a functional hook

Now, this is really impressive

because no other species
actually makes hook tools

apart from ourselves,
not even chimpanzees

And of even more interest
to Alex are these...

Intricately cut tools
from the leaves

of the pandanus tree

Unlike the hooks, there are
distinctly different types

of pandanus tool

This is a single-step
pandanus tool

Essentially, it's a
rectangular piece of leaf

that's been cut out
from a larger piece of leaf

But the crows have gone further
than making a simple rectangle

They also make two-stepped tools

What we've got is a step

So now the end is nice and fine

so the crow can get the tool
into small areas

The third and most
elaborate type of tool

is called
a multistep pandanus tool

This tool has a series
of steps cut into it

and it has that very fine tip
and again that broad end

And across the island,
different groups

of crows use different types
of these tools

In the south, more simple
fragments are found,

but as we move north the crows
start to favor more complex,

multistepped tools

That means that different groups
of crows have their own ways

of doing things

And in human society,
we call this culture

Animals are
creating innovations,

and they're actually passing
them on to future generations

by learning from one another

And basically what
we can conclude is

that there are many species
of animals

that have simple forms
of culture

Humans are not alone
for having culture, not at all

So we're seeing
different populations

that have a single tradition

We've been collecting tools
for the last 15, 20 years

and these traditions
have persisted

So, are parents passing
down these tool designs

to their offspring?

A rare glimpse
of how this might happen

has been captured on camera

Of all the birds,
these crows have

one of the longest juvenile
periods, or childhoods

Youngsters stay with
their parents for two years

Here, an adult bird
is using a stick to probe

for grubs hidden inside a log

A juvenile stands by and watches

The adult departs and leaves
the stick in the hole

The younger bird
can now try the tool out

Although this one
has some way to go

before becoming an expert
like its parents

It looks like
one way ideas spread

through the crow population
is through family groups,

the social circle

And Alex's research
suggests something

even more extraordinary...

That with each
generation of crows,

the tools are honed and improved

The crow's tools have got
progressively better over time

As they've passed on these
tool designs between them,

they've added small tweaks
and this has made the designs

more and more efficient

The New Caledonian Crow
has only been closely studied

since the early 1990s

In that short period,
scientists have revealed

problem-solving skills
that seem similar to those

of our closest cousin,
the chimpanzee

But perhaps
the most exciting thing

is that we're just beginning
to get a glimpse into the minds

of these animals

We keep finding over and over
again that we share the planet

with other animals
that do remarkable things

that we thought only we do

And who knows what else
they might be capable of?