Nova (1974–…): Season 41, Episode 9 - Inside Animal Minds: Dogs & Super Senses - full transcript

From PBS - What is it like to be a dog, a shark or a bird? This question is now getting serious attention from scientists who study animal senses. Humans rely on smell, sight, taste, touch and sound; other animals have super-powered versions of these senses, and a few have extra senses we don't have at all. From a dog that seems to use smell to tell time to a dolphin that can "see" with its ears, discover how animals use their senses in ways we humans can barely imagine. But it's not just the senses that are remarkable -- it's the brains that process them. NOVA goes into the minds of animals to "see" the world in an entirely new way.

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What are they thinking?

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 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
opens a new window

on the roots
of animal intelligence

Explore their language,
relationships, even emotions

If you start giving
one of them grapes,

then the one who gets cucumber
becomes very upset

Are they more like us
than we ever thought possible?

Having a sense of self

would go with complex
understanding of others

In this episode,

who wins the battle
of the super senses?

They have hundreds of millions
more receptors

in their nose than a person does

But could a dog smell time?

5:00, he's there at the door
waiting for him

How do animals
experience the world?

There are animals that have

completely different senses
than we have

If would be close to impossible
to conceive

what that might be like

A new look "Inside Animal Minds:

Dogs and Super Senses,"
right now on NOVA.

What's going on inside
animal minds?

How can we even begin
to understand them,

what they know
and how they think?

If we're interested
in knowing anything

about what an animal

I think we have to know

the kind of information
that they perceive,

and that's all about
their senses

I think our senses
are on the front line

of everything
we're doing mentally

But when it comes
to sensing the world,

all animals are not
created equal

We humans rely
on five primary senses

But some animals have the power
to perceive things

in ways we can't even imagine

Can we ever understand
how their super senses

shape their minds
and their behavior?

Scientists are trying to step
into the skin

and fur and feathers
of all kinds of creatures

to try to discover
how they sense their world

And they're finding

that some of the most impressive
powers of perception

can be found very close to home

As any dog owner knows,

this animal can be
a bit obsessed with smell

So for a dog, I think
you have to understand

that they are going
to experience the world

through their nose

The dog's entire experience
will be about sniffing

everything they encounter
in the world

But just how good is this nose?

The dog sense of smell

is much, much, much more acute
than the human sense of smell

To find out just how powerful
a dog's sense of smell can be,

we're putting a particular pooch
to the ultimate test

Neil Powell trains sniffer dogs,

and one of his top performers
is Fern

Today, she's going to try
to sniff out something

that's been hidden:
a canister containing meat

But here's the twist:

the canister is not hidden
in the woods

or even on dry land

It's at the bottom of this lake,
20 feet underwater

So this is an ultimate test

of the dog's scenting ability

It's probably as difficult
as it gets

Fern has been trained
to detect bodies

that have come to rest beneath
the surface of the water

Several hours ago,

a team dropped the meat
in the lake

and recorded its position
with GPS

Neil only knows roughly which
section of the lake it's in:

an area equal to about 30 acres

The question is,
can Fern find the exact spot?

The team's search technique

is to systematically
criss-cross the lake,

starting at the downwind end

Around ten minutes
after they start

to criss-cross the surface

Fern gives her signal

She's clearly
picked up the scent

But it takes over an hour
of going back and forth

to pinpoint the exact spot

where Fern indicates
it's the strongest

Bear her up into the wind, John

Right round, John

I'd put her there, John

Neil marks her choice
with a buoy

Now the team
that hid the canister moves in

to check it against the GPS
reading they took earlier

And amazingly,
Fern is within just a few feet

Fern was able to do this
because like all sniffer dogs,

she has a powerful
and well-trained nose

Oh, Fernie!

What a clever girl, Fernie!

Dogs' olfactory powers
are so potent,

they can be harnessed
to find all kinds of things

by sensing just a whiff

of drugs or guns or people

They hunt for victims
in disasters like earthquakes

and avalanches

All thanks to a nose
engineered to detect

the most minute traces
of a scent

A big secret of the dog's nose

is that it splits the flow
of incoming air

into separate streams,

with one fully dedicated
to smelling

The smelling tract is lined
with special tissues

densely packed with sensors

They have hundreds of millions
more receptors in their nose

than a person does,

and they have more elaborate
brain organs

to receive and comprehend
that olfactory information

Dogs can smell traces
of a substance

in parts per trillion

That's the equivalent
of being able to taste

a spoonful of sugar

dissolved in two Olympic size
swimming pools

Some experts believe that dogs
are so in tune

with the changing scent
of their environment

that they can smell things

we would never even realize
could have a smell

For example, is it possible
that a dog could smell time?

For humans, time is a concept

To keep track of it,
we depend on clocks

But could it be
that all a dog needs

to keep track of time
is its nose?

Meet the Threlkeld family:

Christine, Johnny, Faye, Mark

and Jazz, their Hungarian Viszla

They're convinced that Jazz
can tell time

because he knows exactly
when his master Johnny

is about to return home
at the end of the day

As soon as I drive in the drive,
I can see him at the window

As soon as I come in the door,

he's always at the door,
waiting for me to come home

And to witness this,

we left cameras running
all over their house for a week

The family have
a regular routine

Christine and Johnny
always leave the house

at the same time in the morning,

leaving Jazz to his own devices

And every afternoon, Christine
comes home at 4:00 p m

But it's what Jazz does next
that's intriguing

Every afternoon at around 4:40,

about 20 minutes
before Johnny comes home,

Jazz always leaps up
onto the sofa

as if he's waiting for him

He's like a canine alarm clock

Between half 4:00 and 5:00,

Jazz is always looking out
for Johnny

When Johnny comes in,

well, it's off that chair
right to the back door,

and by the time Johnny's there
at the door,

he's there waiting for him

It seems as if Jazz somehow
knows that Johnny's coming home

It's a claim made
by many dog owners

I think he's quite intelligent

So how does Jazz do it?

Now, it could just be that
Christine's coming home

sets Jazz's clock

We know it's not because
he needs dinner or a walk,

because Christine's
dealt with that

There's a theory that
a dog's sense of smell

could play a role

While Johnny is
out of the house,

the smell he leaves behind
gradually fades over the hours

So could it be that

when Johnny's scent drops
to a particular level,

Jazz senses he's
about to return?

Here, boy!

A story like that
makes perfect sense to me

I think it's possible that dogs

are in some way telling time
through the day

by odor concentrations

To test this theory,

at the end of the week,
Christine changes her routine

On her way home, she
swings by Johnny's soccer club

to get some freshly worn

And then when she gets back
at her usual time,

she wafts them around the living
room to spread Johnny's smell

If Jazz is using
the fading smell of Johnny

to sense the passage of time,

then this should be
the equivalent

of resetting the clock

So will Jazz know
what time it is?

It's now less than half an hour

before Johnny normally
comes home

But remarkably, Jazz
for the first time keeps dozing

It's now 4:48

Jazz only lifted his head
for about 30 seconds

He's lying flat out again,

enjoying the heat
of the radiator

Now Johnny's back, and to Jazz,

it seems to come
as a complete surprise

You coming over?


He definitely wasn't
looking for him

It was as if he was
quite content

I think he didn't know
what the time was,

and I think the smell
of the clothes

that I had brought in
had obviously confused him

Now, this little experiment
with one dog

doesn't prove anything

There could be any number
of things Jazz is reacting to

But it's intriguing that dogs'
sense of smell might allow them

to grasp something
as abstract as time

So that to me is wonderful

because it really
shows that for dogs,

smell might give them
a sense of time,

which personally I can't
imagine in my head

with the types of smells
that I perceive

It turns out lots of animals

use their senses
and interact with the world

in ways profoundly
different from us,

especially if that world
is underwater

Dolphin senses are extremely
difficult to study in the wild,

but here at the Dolphin
Research Center in Florida,

scientists are investigating

the extraordinary
sensory talents

of a few dolphins
born in captivity

Like Tanner

Looking up, please


Researcher Armando Rodriguez
has devised an experiment

to demonstrate Tanner's

Tanner has been trained
to mimic a swimmer's behavior,

and he's given
the command to imitate

with this hand signal

Today, the swimmer is Wade,
a dolphin trainer

Wade will perform
an action in the water

that Tanner has to copy

We ask the trainer in the water

to actually do that action,
and ask Tanner then to imitate

But it's not as simple
as it sounds,

because during the experiment,
Tanner will be blindfolded

The team is careful to make sure
Tanner has no idea

which action the trainer
will perform

We actually show the trainer
in the water the action

We don't want to say it

in case Tanner can get a cue
from that

Armando gives Tanner
the signal to imitate,

and then puts an eyecup
over his other eye

So can Tanner imitate
Wade's actions

despite being blindfolded?

Wade is upside down,
and Tanner is upside down, too

Wade spins, and Tanner spins

Good boy, excellent, Tanner

Give me five

Good man

And finally, the bob

Wade bobs up and down,

and Tanner does exactly
the same thing


You're running out, huh?

Very good

You know, I see this every day
and I still cannot get over

how extraordinary it is
that he does this

So how does Tanner do it?

Scientists believe
that although Tanner,

like all dolphins,
has pretty good vision,

he doesn't need his eyes
to see underwater

because he's able to sense his
surroundings in minute detail

thanks to the very special way
he uses his sense of hearing

Dolphins have no external ears,

but their inner ears provide
excellent hearing underwater,

and they put it to amazing use

in a process called echolocation

Here's how it works

The dolphin uses a special organ
behind the forehead

to emit focused pulses of sound,
or clicks

The sound waves from the clicks

bounce off other objects
in the water,

echoing back to the dolphin

Instead of external ears,
a cavity in the jaw

picks up and amplifies
those returning sound waves

before sending them on
to the inner ears

on either side
of the dolphin's head

Echolocation is very similar
to the sonar submarines use

In fact, it was scientists
in the Navy

wanting to improve their sonar

who first figured out
how dolphins do it

They attached small devices
to different parts

of the dolphin's head

These produced sounds
which the dolphin responded to

The strongest response
was measured

when the device was
on the dolphin's jaw

This is how scientists believe
Tanner can copy Wade

He is using echolocation
to essentially see Wade's body

and what he's doing in the water

To us, a dolphin's echoes

may sound like a cacophony
of random clicks

But listen to what happens
when we slow them down

This is a return echo
from an Atlantic cod,

while this is what's
bouncing back to the dolphin

from a different fish:
a mullet

The sound waves don't
simply tell the dolphin

about the outer form
of the fish;

they can reveal shapes
inside the fish as well

Some researchers believe
that dolphins

can tell different kinds
of fish apart

by reading the echoes bouncing
off their internal organs

It's probably one
of the most important,

if not the most important sense
for most dolphins

Echolocation has given dolphins
a clear evolutionary edge

If they're traveling at night,

they're going to need
the navigation

If they're traveling
in murky water,

they're going to need to be fed,

so to be able to detect a fish,
it's a wonderful thing to have

Lots of animals use one
of our five familiar senses

in completely unfamiliar ways

Starfish see, but not like we do

A basic light-sensitive eye
at the end of each arm

can form simple images,

helping them to find their way
around the sea floor

Butterflies and moths
have no nose,

but their sense of smell may be
even more sensitive than a dog's

because of their antennae,

fine-tuned to detect
just a few molecules of scent

For many creatures
throughout the animal kingdom,

the secret to their survival

has been the evolution
of super senses

And these aren't always simply
more powerful versions

of our five senses

Sometimes, animals
perceive things

that our bodies are
incapable of sensing

There are animals that have

completely different senses
than we have,

that it would be close
to impossible to conceive

of what that might be like

One of these animals
thrives here

off the island of Bimini
in the Bahamas:

the shark

Sharks are extremely
successful predators

They can smell tiny quantities
of blood over huge distances

and feel the miniscule
vibrations of prey in the water

But sharks have another sense
that we humans do not share

Researcher Eric Stroud
has devised an experiment

to demonstrate
with young lemon sharks

We've just captured
a juvenile lemon shark,

and to do an experiment
right now,

we need to turn it upside down,

and this is called
tonic immobility,

and after a few moments,

the shark will go
into a sleeplike state,

a comatose state

With the shark at rest,
Eric will test its sensitivity

to something a human would be
completely oblivious to:

a magnet

And this is perfect
to conduct an experiment

because right now,
nothing is bothering it,

so we're going
to introduce a magnet

and we're going to see
if the shark

can sense the magnetic field and
give us some type of response

But I don't want to cheat

I don't want the shark
to see it,

so we're going to put
a small blinder in here

so he can't see me coming,

and now I'm going to put
the magnet in the water

and approach the shark

That was a great response

What we had there was
a repellent response

The shark did not like
this magnetic field

Almost as if he'd had a powerful
light flashed in his eyes,

the shark was acutely sensitive
to Eric's magnet

As a control, Eric does the same
experiment with a piece of lead

And we don't get a response

So this proves it's not just
any piece of metal

that can interfere
with the shark's magnetic sense;

it really has to be
magnetic in nature

Sharks are clearly affected
by a magnetic field,

but they don't typically
encounter magnets

in their environment,

so why have they developed
this sense?

What we did in that experiment

is we induced a very strong
electromagnetic field

The movement of a magnet can
induce an electrical current

Magnets generate
a weak electrical field...

A flow of charge...

And so do the muscular
movements of prey,

including their beating hearts

When that animal is beating
or it's moving,

the muscles generate a very weak
electromagnetic field,

and that's what they're
gearing in on

They can locate the heartbeat
of, say, a crab or stingray

underneath the sand

It's another tool
in their predatory arsenal,

making it even harder
to hide from a shark

All thanks to an ingenious piece
of sensory anatomy

Sharks have organs called
the ampullae of Lorenzini,

which appear as dark openings
along the front of their noses

These are the ends of tiny tubes
filled with a jelly

The jelly can register
voltage differences

between the tube's opening
and its base

beneath the shark's skin

These are exquisitely sensitive,

able to pick up
billionths of a volt

So we've seen the effect
of a magnet on a young shark,

but could it have any effect
on a full-grown one?

Eric is heading out from Bimini
to Triangle Rocks,

a well-known gathering place
for large Caribbean reef sharks

He's joined by his colleague,
marine biologist Pat Rice

Together, they've come up
with a plan

to test a shark's magnetic sense

against one of their most
powerful instincts:

their urge to eat

We've just arrived
at the Triangle Rocks...

That's south
of South Bimini island...

And when we set up here,

six Caribbean
reef sharks arrived

These are adult sharks

and they vary between
maybe two to three meters

There's one big one down there

With the sharks gathered
around the boat,

Pat gets ready to dive in

This is probably
my hundredth dive

with these particular sharks,

and if you aren't
afraid of them,

they will stay away
from you, usually,

unless, you know, sometimes when
they get into a feeding frenzy,

all bets are off then

So here we have a Pelican case
full of magnets

See if I can get one off here

You can see
how powerful they are

Takes a Herculean task
to get them apart

These are barium ferrite,
ceramic magnets, very powerful,

so it's probably a good idea

to keep the cameras
away from them at least a meter

because anything that's magnetic
memory can be wiped clean,

so we don't want
to lose the shot

At the surface, Eric distracts
the sharks by feeding them

while Pat sets up the experiment
on the ocean floor

Right now, the key is to try to
keep the sharks near the surface

so that the divers can set up
the experiment down there

and the sharks are above them

25 feet below, Pat makes
two circles in the sand:

one with magnets
and one with bricks

He places the same
amount of bait

in the center of both of them

All the sharks up by the boat

will now be able
to smell the food

The question is,
will the magnets stop them

from eating the bait?

Here comes a shark,

and he ate right off the control

One shark bypasses the magnets
on the left

and goes straight into
the brick circle on the right

to take the bait

So will they take an interest
in the bait

inside the magnet circle

now that the brick circle
is empty?

Another animal moves in,

but before it can grab the bait,
it turns away

It seems to know
there's food there,

but it won't go
inside the ring of magnets

Jess, get more bait

Pat puts fresh bait
in the bricks

They're getting
a little feisty down here

But he's barely
had time to retreat

when a shark goes straight
for the brick circle again

We can't get it down fast enough

More bait, Andy!

The sharks grab the food

as soon as it's laid down
inside the bricks

Pat has replenished it
four times

They're pretty hungry today

But they don't touch the food...
a delicious fishtail...

Inside the magnets

Unlike this experiment,
in which the electric field

is overwhelmingly strong
and repels the sharks,

in the wild,
much weaker electric fields

produced by the moving muscles
of fish and other creatures

can actually attract them

We may never really
understand fully

how a shark is perceiving
the world around it,

and in this particular case,

because we don't have
an electric sense,

we have to kind of guess

Sea creatures have evolved
their own special ways

to perceive their watery worlds

to find prey
and help them navigate

What if your world
is not underwater

or on land,

but in the air?

Consider these birds
zipping around in the sky

They've got a lot to take in,

plus they need to migrate
hundreds of miles every year

Yet if they're going
to defy gravity,

they can't be weighed down
by a big brain

If you're a bird
and you need to fly,

you're going to have to have
a way to do it

so that your brain
doesn't weigh so much

that you can't get there

Birds on the wing can move
in any direction they choose

In some environments, there's a
constant risk of collision

What's more, predators
in the air, like hawks,

can attack from anywhere

So bird brains need
to take in information

from every direction

Many can see down, up,
left, right,

in front and behind,
all at the same time

And yet with nearly
300-degree vision,

a swallow can pull complex
maneuvers at 40 miles an hour

within inches of buildings

It's an incredible amount
of visual data to process,

all achieved with a tiny brain

A swallow's brain
weighs about one gram,

1,000 times lighter than ours

So how on earth do birds do it?

Clues might come from this
reconstruction of an experiment

based on research
originally conducted

at the University of Queensland

and Australian
National University

It involves some boards
with stripes painted on them

and a starling named Arnie

Are you ready?

We're going to get him to fly
down this corridor

And to begin with, we'll have
these stripes horizontal

and we'll time using
these precision timing gates

how long it takes him

Then we're going
to switch the boards

so that the stripes
are vertical,

and we'll see how that
changes things

To get a precise measurement
of Arnie's speed

as he flies down the corridor,

the starling must fly through
a light beam at the start

and at the finish

To make sure the results
are reliable

Yep, that worked

Arnie must complete at least
ten successful flights

Arnie's performing admirably

His flight times from one end
of the corridor to the other

are coming in
at less than two seconds

Yep, we've got ten

Now what we're going to do
is change the boards

and make them vertical

And we're going to try again
and see how that affects

the speed that the birds go at

With the stripe pattern changed,
the team repeats the experiment

That was the slowest time so far

Could the vertical stripes
really have slowed Arnie down?

Once we have a complete set
of flight times,

we can compare
how fast Arnie flew

through the vertical stripes
versus the horizontal

The average speed
for the horizontal stripes

was 16 5 feet per second

But for the vertical stripes,

it was only 15 3 feet per second

These results confirm
that the vertical stripes

slowed the bird down
by more than a foot per second

The reason why we see this

comes down to a neat trick
called optic flow

Optic flow is the way
animals' eyes sense motion,

and birds use it to help them
determine how fast to fly

When Arnie flies
through horizontal stripes,

the pattern changes very little

That pattern of information

is very smooth
and very continuous,

just as it would be

if the bird is flying
through an open environment

with objects way off
in the distance

But the vertical stripes create
an entirely different illusion

That's interpreted

as the bird being in a very
cluttered environment

with lots of objects,
like trees,

that it has to fly between
and navigate past

And so what it does is
it flies more slowly

When Arnie flies
through the vertical stripes,

the pattern changes constantly

His brain may be perceiving
the lines as nearby obstacles,

that makes him fly cautiously,
over a foot per second slower

The bird is able to make
these adjustments

based on minimal
visual information

Whether sharks or dolphins,
birds or butterflies,

all these animals make decisions

based on what their senses
tell them

And most of them, like us,

perceive the world
with multiple senses

So how do they put it
all together?

Evolution can design an organism
in a lot of different ways

in terms of how they listen
to their senses

And so you can see an organism
that is able to integrate

all their sensory input
at the same time

You can have another organism

that may prioritize
one sense over another

The way animals
prioritize their senses

can have a profound impact
on their behavior,

especially if those senses

seem to be delivering
conflicting information

So how do animals decide
which sense to trust the most?

Some intriguing research
is delving into that question

with our trusted companion,
the dog,

and comparing it
to its closest relative,

the wolf

Wolves are genetically
almost identical to dogs

The animals can even interbreed

But in the 10,000 years or more
since some were domesticated,

wolves haven't changed much
in appearance,

while dogs have been bred

to take on an astonishing
variety of shapes and sizes

But how different are dogs
and wolves inside their minds?

Do they use their senses
in the same way?

Here at Wolf Park in Indiana,

animal behaviorist Kathryn Lord
is trying to find out

She's studying a group
of ten wolves born in captivity

who now roam over a territory
of about 75 acres

Like most mammal predators,

wolves rely on their nose
to track down prey

Without it, they would starve

At Wolf Park, all the wolves
have been raised by humans

and have no need to hunt
for their supper

But they haven't lost their
acute appreciation of smelling

And as Kathryn has found,

they seem to have
some expensive taste

So I'm going to spray

this bottle of Channel No 5
over there

to see if we can't get
some scent rolling

So they come over here
and actually start pushing

their head and shoulder
into the ground

and rolling around in it

Dog owners might recognize
this kind of behavior,

but to scientists,
it's a bit of a mystery

Some think that wolves
developed this as a strategy

to carry interesting odors
back to their pack

We're not completely sure
why wolves

actually do this behavior

This particular perfume
as well as a number of perfumes

have a musk in them

which may be similar
to some pheromones

which are very important
to wolves

It may make them more attractive
to have the scent on them,

or they may just be trying
to show other wolves

that they've found
an interesting scent

We really don't know

Pheromones are natural chemicals

that can send signals
from one animal to another:

signals about fear or food
or finding a mate

Smell clearly plays a central
role in a wolf's life,

as it does for a dog

So dogs and wolves both have

an excellent sense of smell

They both seem to inhabit
the same sensory world

Let's go!

But as important as smell is,

are wolves and dogs slaves
to their noses?

As most dog owners know,

in addition to being
great sniffers,

these animals watch us
very closely with their eyes

and seem very interested
in what we do

So what role does vision play

in how dogs
understand the world?

Brian Hare has recruited dogs
from across the country

to test how they use
visual information,

when that information

is provided by a human

Okay, Sisu, stay!

One of the simplest examples
is the Pointing Test

And now watch
where her gaze goes,

right at me


All right,
so what we've got here

is a very simple experiment

We've got two people,
we've got two cups

We've hidden food in both cups
and we have a dog, of course

And all I'm going to do is

I'm going to gesture
to one of the two cups,

and the question is,

does the dog go where I gesture
or to the other cup?

Now, it can't be that
she's just using her smell

when she makes her decision

because there's food
in both cups

So let's see what she does

Both cups are hiding food

and smell equally appetizing,

so there's only one reason
for Sisu

to choose between them

Sisu, you ready?

The visual signal
Brian is giving her

Okay, Sisu

Good job

And there's one here, too

All right, so she did use
my gesture there

Sometimes I'll point
to the right

and sometimes I'll point
to the left

But let's do it again,
because it could be chance


Okay, Sisu

All right!

So what we've seen is that Sisu

really relies
on my visual gestures

She's not relying on her nose

If I'm there
and tell her something,

she's much more happy
to use that information

than to rely on her nose

It's not too surprising


Many dogs will eagerly follow
visual cues and gestures

given by humans, like pointing

Callie, is it there?

But we also know
they have great noses

So what happens when the two
senses... vision and smell...

Go head to head?

To find out,

Brian is going
to put Dexter's nose

in direct conflict
with Dexter's eyes

So we're going
to actually show Dexter

where we're going to hide
the food,

so he can remember
where he saw it

But then what we're going to do
is we're going to close his eyes

and then we're going to shift
where it's hidden

We're going to actually move it
to the other location

So that means he could
potentially smell where it is

The question is, does he use
what he saw to find the food

or does he rely on his nose?

So let's see what he does

All right, Dexter

Oh, look at that face

Oh, you're killing me

All right, Dexter,
are you ready, buddy?

Okay, that's where it's
going to be

This time, there's food
under only one cup

Okay, now close your eyes

And with Dexter's eyes covered,

Brian now moves the food
to the other cup

Poor Dexter's senses
are in direct conflict

Does he trust his eyes
or follow his nose?

Okay, Dexter, find it!

Aw, what happened?

It's a trick!

It's over here!

It was a trick!

Are you ready, Dexter?

Okay, we're going to put it
over here

Here it is

Close your eyes

Okay, Dexter, go get it!

Again and again,
Dexter, like most dogs,

goes not to where
he can smell the food,

but where he saw Brian
put the food


But what about wolves?

Will they pay attention
to visual cues from humans

in the same way?

Back at Wolf Park,
researchers are investigating

Hey, babies, hello

Kathryn Lord reared
this group of wolves from birth,

so unlike wolves born in the
wilderness, who avoid humans,

these can be quite friendly

Still, they are wild animals
and potentially dangerous,

and Kathryn knows to be careful
in their presence

If I was very hurt,

if I had a broken leg
or if I was very sick,

I probably wouldn't come in

just because I'd be
sending them signals

that might lead
to that sort of behavior

But otherwise, they're very
well socialized to humans,

so that's not usually
too much of a concern

Growing up with exposure
to humans

and receiving treats from them,
this grey wolf Fi responds

to certain types of information
that a wild wolf wouldn't

She comes when her name
is called


And Fi can also follow
Kathryn's pointing

She seems to be just
as capable as a dog

of understanding what it means

But other tests
with dogs and wolves

reveal a dramatic difference
in their priorities

when it comes to paying
attention to people

When researchers
from Oregon State

gave wolves a closed container
with a tasty treat inside,

the animals focused intently
on getting the food out

But pet dogs,
given the same container,

tend to focus on their owners

Get it!

Only when the humans
actively encourage them

do the dogs really work
at getting the container open

So it's not that wolves
can't pay attention to humans,

but on a very fundamental level,
they don't need to

If they were students
in a classroom,

the wolf would be focusing
down on the test

and solving the problem

The dogs would be cheating by
looking at somebody else's test

So the dogs need us
to solve the problem

whereas the wolves
are perfectly capable

of doing it on their own

This is one of the key changes
that occurred in the wolf mind

when they were domesticated
and evolved into dogs:

they became extremely willing

to watch and pay attention to us

This may explain why
in some cases,

a dog will choose
to follow human gestures

instead of its own extremely
powerful nose

We're kind of suppressing
dogs' olfactory experience

We are in control,
for the most part,

of owned domestic dogs' lives

So how did this
transformation take place?

Kathryn believes this difference
between wolf and dog minds

may be closely linked
to how the animals

process sensory information
in the earliest weeks of life

Kathryn raised wolf pups
from a very young age

The wolf pups are great

So we get them at
about ten days of age

So at that point,
they can't see,

they can't hear
and they can't smell,

and they can't
really walk either

They're just kind of
little puddles of fur

You basically are a warm water
bottle that feeds them milk

So we bottle feed them
every four hours

It's very intensive,
you're with them 24/7

It's the only way
you can socialize them

There's a brief period of time

when baby animals
are open to new experiences

and become socialized

It's known
as the exploration window,

and it's a chance for them
to learn who and what is safe

while they're protected
from predators

Kathryn found that in wolves,

this window opens very early,
at two weeks,

when only the pups'
sense of smell is working

and they are still
blind and deaf

Over the next few weeks,
the pups start to see and hear,

but also gradually become
more fearful of new sensations

Dog puppies also have
an exploration window,

but it opens slightly later

The big difference is when they
start to explore their world

So dogs don't begin
to explore their world

until four weeks of age,

so that's two weeks later
than the wolves

And so when the dogs
start to explore their world,

they can already
see, hear and smell

But while the dogs have
all their senses powered up

when they're getting
to know their world,

with fewer senses working,

will be exposed to far fewer
sensory experiences

before their fear of the
unfamiliar is firmly in place

Kathryn believes this is
one of the main reasons

wild wolves avoid humans

Even a well socialized wolf
is very different

from a well socialized dog

The wolves are more fearful
of novelty in general

than a dog is

Dog puppies can be exposed
to all sorts of sights,

smells and sounds
during their exploration window,

so when they're older,
more things will feel familiar

and they'll be more open
to new situations

This may help explain why dogs

can so easily form close
friendships with other animals,

whether human or not

The ability of dogs to be
flexible is what allowed them

to come into our environment
in the first place

and probably allowed them
to be domesticated

The early wolves
that evolved into dogs

were perhaps quite different
from the wolves of today

As pups, they may have had
a later window of exploration,

leaving them more open

to forming close relationships
with humans

For Kathryn, what might seem
a small difference in timing

during development
has had a profound impact

on how these two animals
use their senses,

and may be a key factor
in creating the dog mind,

comfortable around humans

and primed to become
a close companion

We're so close to our dogs
that some of us imagine

we can guess
what's on their minds

But for scientists,
it's a lot more complicated

One of the big questions,
of course,

that people have always
been interested in is,

do animals think at all?

And in asking that question
about animals,

it makes you think about
what is thought

and what drives
what we are thinking about

For decades, animal researchers
have relied on behavior

to try to determine
how animal minds work

But now things could be changing

because for the first time,

we may have a direct window
inside the animal mind

Neuroscientist Greg Berns
is adapting a medical technique

to study the activity
of brain cells in dogs

Okay, so stand by,
we're going to start the noise

MRI is a technique
that's been used in humans

for over 20 years

Normally, we use it
to study what the brain looks

but with a few tricks,
we can actually do

what we call functional MRI,

which looks at brain activity,
and by analyzing the data,

we can figure out what parts
of the brain are doing what

But doing MRI on animals
is an entirely different game,

mainly because
of the requirement

that the subject has to hold
absolutely still

The need to keep still makes it
impossible to scan most animals

unless they're sedated,

which is not a good way
to study brains in action

One, two, three, steps!

But Greg has teamed up
with Mark Spivak to train dogs

for the unfamiliar conditions
they'll face

inside an MRI machine

One key requirement
is a steady supply of snacks

Well, a lot of humans

have difficulty taking MRI

First of all,
there's the enclosure,

which provokes anxiety
in many humans

Second, there's the absolute
motionlessness required

And then there's the noise

To block out the MRI noise,

the dogs are trained
to wear special ear covers

Without proper conditioning
and training,

the dogs would just run scared
from the MRI

Come here, girl!

Those that pass the test

graduate to the real thing,
like Kady

MRI is a noninvasive technique

at the very cutting edge
of animal science,

and it's beginning to reveal
fascinating insights

Patricia, we're going
to begin the first scan

with the localizer,
are you ready?

One of Greg's earliest

is revealing an important clue

as to what happens
in a dog's brain

when it receives information
from its senses

First, Kady is looking
at a visual signal

So Kady's in the scanner
right now

and Patricia's actually giving
Kady hand signals

So we've already taught the dogs
through lots of practice

that this means food, okay?

So every time Patricia
puts this signal up,

we're going to be looking
in her brain,

what that brain response is,

and we're actually going to be
looking at a very specific area

called the caudate nucleus

We also have another hand signal

that looks like this,
and that means no reward

After scanning many dogs,
Greg's results reveal

the area of the dog's brain
that responds

If we look very closely,

we find that the area
that's common to all the dogs

corresponds exactly to the same
part of the human brain

that responds to reward

Rewards like money, music, food,
all the things that humans like,

it's also activating
in the dog's brain

Even though Kady
isn't actually seeing food,

she can take a piece
of visual information

and interpret it to anticipate
that she will receive food,

and she's responding
emotionally, just like we do

This was pretty amazing

because it didn't have to be
that way

Dogs could be so different
from us,

they might have responded
completely differently,

but that doesn't seem
to be the case

And this reveals a complex chain
of brain activity

Ever since Pavlov,
people have viewed animals

as Pavlovian machines:

stimulus-response robots,

And what we're finding is that
there's a tremendous amount

of processing
going on in their brains

that looks actually a lot like
what happens to humans

in exactly the same

Dogs and probably most animals

have brains and minds
that are far more sophisticated

than we ever
gave them credit for

It's one of the great mysteries:
what are animals thinking?

Now, we are gaining
ever-greater insights

into their senses,
painting a clearer picture

of how the creatures around us
perceive their world,

whether it be dramatically
foreign to our own

or remarkably familiar