Inside the Animal Mind (2014–…): Season 1, Episode 1 - You Are What You Sense - full transcript
I've spent most of my life
watching animals.
And there's one question that
obsesses me.
What's it like being an animal?
This is Itchy
and Scratchy. I've had them
since they were 6 weeks old,
I've raised them, I love them
so much and just like all dog owners
I sometimes gaze into these
little chestnut eyes and wonder -
what's going on inside that head?
And you know, I would give
anything to be another
animal for just five minutes,
to be able to experience the world
the way they perceive it, to know
what they're thinking.
To be INSIDE the animal mind.
It's one of the great
mysteries of the natural world
and now, new research is
starting to give answers.
Wow.
In this series,
I'm going to seek out
the most powerful
animal minds on the planet
and find out
what they're capable of.
Look at that!
If I'm really going to get
inside the minds of other animals,
the first thing
I need to do is to discover how
they experience the world
around them.
I mean, imagine how different this
world is to my dogs.
To them, this is a landscape
of smell.
We both live in the same world
but we experience it in completely
different ways.
In this first programme
we'll investigate
the sensory secrets of the animal
we know best of all.
Close your eyes.
Dogs.
Aww, what happened?!
And test them
against their ancient ancestors.
We'll be discovering how the
minds of very different animals
perceive their world
through their senses.
And I'll come face-to-face
with an animal that
most people wouldn't want to meet in
their nightmares as I learn about
the remarkable sixth sense of
sharks.
Animal senses define the way
they think.
They're the gateway
to the animal mind.
Castlewellan Lake
in Northern Ireland.
I've come to its rain-swept
shores to see a dog do something
that I thought impossible.
Now, obviously, Itchy and Scratchy
have got a pretty
good pair of noses.
But what I've always wondered is
just how good is the dog's
sense of smell?
Well, today we're going to put
the dog's nose to the ultimate test.
Neil Powell trains sniffer dogs.
And one of his top
performers is Fern.
Now, Fern usually works for the
Search and Rescue Dog Association.
But today, she's going to try and
sniff out something
that Neil has hidden.
What's extraordinary is that
it's not on dry land.
It's in the lake.
It's underwater.
Here she is, Fern.
Looking keen and all dressed up.
What type of spaniel is she?
She's a mixture between
Cocker and Springer Spaniel.
So, she's known as a sprocker.
A sprocker.
Now, let's get this straight.
You've already been out this morning
and you've hidden a lure
IN the lake?
And we're going to go out
and she's going to sniff it? Yeah.
And find it?
Yes, what we've done is,
about two hours ago we hid a small
canister in 20 feet of water.
It's got some pork meat in it.
I know where it is but she doesn't,
so we're going to search the lake now
with her and, hopefully,
we'll get to
within about 30 feet of it.
Come in then, Fern. Let's go for it.
I really do need to see this.
Can a dog really smell
something on the bottom of a lake,
in driving rain and strong winds?
Sounds improbable.
Neil and the dive team know
precisely where the canister
is hidden because they fixed
a GPS position on it
when they dropped it into the lake.
The question is, can Fern find it?
Of course, this isn't a stunt that
Neil and Fern pull off
for the joy of it, she's been
trained to detect bodies that have
come to rest
beneath the surface of the water,
there's a very serious side to this.
Nevertheless, it's pretty
counterintuitive, isn't it?
Here we're asking a dog
to smell through six metres,
20 feet of water.
And when you think about it, in all
those movies and cop shows
we've always watched,
when the criminal's fleeing,
they run up the stream
so they don't leave any scent
because the dogs can't sniff them.
Well - criminals, if you're
watching this,
you might have to think again.
The team's technique is to
systematically crisscross the lake.
So, at some point,
Fern will find herself directly
downwind of the sunken canister.
But will she pick up the scent?
The lake is a mile long
and half a mile wide.
And only the tiniest quantities
of chemicals from the meat
might reach the surface.
And of that minute trace, almost
all of it will get blown away.
And yet, around ten minutes
after we start...
..Fern senses something.
That's the scent.
Turn it up to the wind, John.
We start circling,
narrowing down the location.
She's got the scent,
how are you going to know when we're
in the closest possible spot?
When she arrives over the top of it
you'll see her going over
the side a little bit more and she's
really focused on the water.
You're getting her right into the...
see, there, see that? Yeah.
Bring her round there, John.
Right round, John.
I'd put her there, John.
Fern has made it quite clear
where she thinks
the source of the smell is.
Fern is confident which in turn
means Neil is very confident
and they've dropped the marker in
and the thought is that we
could be within just a few
metres of where the lure is hidden.
But the one thing I will say is I'm
sat here as any other human being
would be, with no sense
at all, using a sense
of smell that we are in the right
place. All I can smell is a
slightly fresh, rainy, damp,
very pleasant afternoon
in Northern Ireland.
There's only one way to know
if Fern's chosen the correct spot -
The dive team check
it against the GPS fix they took
when they threw
the canister into the water.
And, unbelievably,
Fern is bang on top of it.
The divers' final job is to
retrieve the canister.
But the lake bed has a surprise.
The bottom is a metre of soft silt
and the canister has sunk
right into it.
So, amazingly, Fern hasn't just
sniffed the lure through
six metres of water but also through
a metre of mud as well.
What an absolutely
astonishing thing.
Now, I've seen animals over the
years pull off some remarkable feats
but this has been something
else, it really has.
There ye go, what a clever girl.
Good girl. Clever girl
'And the reward for all her efforts?
Just an old tennis ball.'
Fern's training might give her
this special ability.
But all dogs have an extremely
powerful nose.
They can smell in parts per
trillion, the equivalent of being
able to taste a spoonful of sugar
in two Olympic-size swimming pools.
So, how on earth can dogs do this?
Well, it's all down to a nose
that's nothing like ours.
Each nostril can be controlled
independently, allowing dogs
to detect precisely the direction
a smell is coming from.
And what goes on inside
is even more impressive.
You see, dogs split the flow of air
into two separate streams,
one for breathing
and one for smelling.
So they can do
both at the same time.
It's a superb tool for gathering
sensory information and it means
a dog's mind understands the world
in a completely different way to us.
Their world is a complex smellscape
in which they can sniff out
an animal that's too far off to see.
Or pick up the tiniest
trace of odour left on a leaf.
But although smell is vastly more
powerful for dogs than it is
for us, it's one of the five
senses that we share
with them and most other animals.
And there's a reason for that.
The senses are the front line
in the way that animals interact
with the physical world around them
and this goes a long to explain how
those senses actually work.
Whatever kind of animal you are,
you experience the same
physical properties.
I need vision to see light
bouncing off objects -
I need touch to feel surfaces
and sense temperature.
I need to smell
and taste chemical substances.
And I need hearing to detect
shockwaves in the air.
These are my five basic senses to
guide me through the world.
Perhaps it's not surprising that
I share these with the
vast majority of other animal
species in some combination or other
for the very simple reason that we
all inhabit the same physical world.
And yet - those five familiar
senses can be used by
some animals in ways that are
totally foreign to the human mind.
I've come to the Dolphin Research
Centre in Florida to see
something that dolphins can do
with their sense of hearing.
Now, it's hard to study
dolphins in the open ocean.
But keeping them in captivity is
controversial.
And since 1988, aquariums in the
United States
don't take dolphins from the wild.
Dolphins like Tanner were
born in captivity.
Tanner, are you ready?
No? Yes, you are ready.
Researchers Armando
and Wade want to show me
an ingenious experiment to
demonstrate how Tanner uses sound.
I have a list of behaviours
right here now, I can't see them,
please don't show them to me...
I'm going to select
an action from a list for Wade to
perform in the water.
Wade, go ahead in.
I'm only showing Wade,
Armando and Tanner have no idea
which one he's about to do.
OK, Wade, let's go for this one,
please? OK?
Tanner, imitate.
'With his eyes covered, Tanner will
now attempt to imitate Wade.'
Then the other one will go on the
left eye, but I have to give him
the signal first, which means
imitate.
Are you ready?
Imitate...
'So, will Tanner know what
Wade is doing?'
There he goes, Wade is upside down
and Tanner is upside down as well.
'OK. That's one out of one.
'But for something this bizarre,
I need a little more proof.'
Shall we try another?
Try another one?
Let me put the eyecup on.
Let's go for this one, Wade...
And here we go...
'Tanner appears to take a moment to
listen before imitating
'Wade's exact movements.'
It's pretty impressive,
I have to say.
'And for the piece
de resistance, the bob.'
Next word...
Now, watch. He's reading.
He's reading, without
a shred of a doubt.
He's reading without seeing.
There's no question of that,
and getting it right.
Good boy, Tanner. Thank you very
much, thank you. Excellent!
Tanner, you're the best.
'So, how does Tanner do it?'
Scientists believe he's using
sound in an unusual way.
It's called echolocation.
A specialised
fat-filled organ called
the melon behind the forehead emits
focused pulses of sound.
But the key to echolocation is
listening to the
echoes of those sound
waves as they come back.
Dolphins pick up and amplify those
returning waves with
a cavity in their jaw, before
sending them on to the inner ear.
They use echolocation to hunt down
and pinpoint their prey
even in darkness.
Dolphins share this use of hearing
with nocturnal animals like bats.
But just how detailed
a picture of their world can
they build up in their mind,
using this one sense?
When we hear that burst of sound
being pumped out by the dolphins
it's no more than a rapid cacophony
of random clicks as far as
we're concerned,
but this I think will
surprise you, because if we process
the return echo simply by slowing
it down, this is what we can hear.
This is a return echo
from an Atlantic cod, whilst this...
..is what's bouncing back to
the dolphin from a mullet,
so clearly for the dolphin it's
a very sensitive sense, it can
tell the difference between these
two different species of fish,
perhaps even choosing which one
it wants to eat.
The dolphin's echolocation is
an extremely powerful sensory tool
which allows its mind to build
up a picture of the world.
But at the moment I'm left thinking,
what does a dolphin actually
do mentally? What does it think
with all of that echolocation?
Does it turn it into a visual image?
We don't know, we may never know.
But one thing I'm sure of is
that this will have
a profound effect on the way that
these animals think.
Countless other animals use their
five senses in ways which,
to us, are unfamiliar.
Starfish see, but not as we do.
A basic eye at the end of each limb
can form simple images,
helping them find their way
back to their feeding grounds.
Butterflies and moths have no nose.
But their sense of smell is many
times more sensitive than
even a dog's.
And it's thanks to their antennae.
In some species the antennae can
respond to only a few
molecules of scent
from a potential mate.
When I was a kid we called them
"feelers"
but they're actually being
used for smelling.
Across the animal world, species
evolve the senses which give them
the best chance of surviving
in the environment where they live.
But very often, individual species
or groups of species will form
a sort of a sensory hierarchy in
that one or two senses will become
far more sensitive than the others.
So, if two animals have
a different dominant sense,
how far does that influence
the way that they think?
I've come to Wolf Park in Indiana,
to find out.
Scientists here are studying
a group of ten wolves
that roam over
a territory of a dozen acres.
Wolves are fascinating
because, biologically,
they are the same as dogs.
Around 10,000 years ago, humans
began domesticating some wolves,
and over time they created dogs.
Now, wolves haven't changed
much in that time.
Dogs, on the other hand,
have evolved into an astonishing
variety of breeds.
They look very different
to wolves.
But how differently
do their minds work?
To give us some insight,
we're going to test dogs
and wolves in a battle
of the senses.
So first, I want to establish
the sensory abilities
these two animals share,
starting with smell.
This couple of wolves down here
are about, I don't know, 60m away
and I'm going to test that
sense of smell.
They've got expensive tastes, these
animals, because what I'm going
to use is this, Chanel No 5.
It's said that they have
a real craving for it.
So, I'm just going to sneak down
here...
..put some of this on the grass...
..and see what happens.
Well, there goes a tenner, at least,
let's see what happens.
But it's not so much picking up
that scent, it's what they do
when they find it that we're
interested in.
Nose is up.
Yes...
Look at that...
This is what we call scent rolling
and I'm afraid to say that
many of you have probably seen
your dogs doing this
in less pleasant things than
expensive perfume.
It's brilliant, isn't it?
On the face of it, it seems that
dogs and wolves live in the
same sensory world and it's a world
dominated by the sense of smell.
Let's go!
But that's not the only sense
that's important to dogs.
Let's go.
Any dog owner knows they
watch us closely with their eyes.
So, what role does vision play in
how dogs understand the world?
Dr Brian Hare has recruited
dog owners from across the US
to carry out
some simple tests that show how
they use visual information.
OK, Sisu, stay.
OK. One of the simplest is called
the Pointing Test.
And now watch where her gaze goes.
Right at me. Stay.
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 at 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 smell equally appetising.
So, there's only one reason for Sisu
to choose between them.
OK, Sisu, you ready?
This. OK, Sisu.
It's the visual signal that
Brian is giving her.
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.
Hey. OK, 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 telling her
something, she's much more
happy to use that information
than to rely on her nose.
Most dog owners will be familiar
with this ability.
OK, Kai. Dogs will readily follow
visual information.
Callie, is it there? But we also know
they have great noses.
So, which sense do dogs trust
the most - vision or smell?
In a new test, 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 shift where it's hidden and move
it to the other location.
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.
Look at that face.
You're killing me.
All right, Dexter,
are you ready, buddy?
OK, that's where it's going to be.
This time there's food
under only one cup.
OK. Now close your eyes.
And without Dexter seeing,
Brian's now moving that
food to the other cup.
Poor Dexter's senses are in
direct conflict.
So, does he trust his eyes
or follow his nose?
OK, Dexter, find it!
Aww, what happened? It's a trick!
It's over here, it was a trick!
Are you ready, Dexter?
OK, we're going to put it over here.
Here it is.
Now, close your eyes.
OK, Dexter, go get it.
Again and again, Dexter, like most
dogs, goes not to where
he can smell the food but where
he SAW the food.
OK, Dexter, get it!
Awww!
It tends to be that
if they have visual information
they prioritise that, they actually
put that in front of what
information they might be
getting from their nose.
But what about wolves?
Do they prioritise their senses
in the same way?
Well, back at Wolf Park,
we're going to test them.
Kathryn Lord from the University
of Massachusetts
reared this group of wolves
from birth and they're
certainly familiar with humans.
I know, I'm going to stand up
for a second
cos you're getting a little
excited, I know.
So, this grey wolf Fi can understand
certain types of information
that a wild wolf wouldn't.
She comes when her name is called.
Fi!
And, remarkably, Fi can also follow
Kathryn's pointing.
She's just as capable as any dog
of understanding what it means.
Hey.
We've seen that dogs trust this
visual signal above smell.
So is this also true of wolves?
To find out, we're going to repeat
the finger pointing test
several times,
just as we did with the dogs,
with a snack under each can.
Fi!
So, will Fi the wolf respond like a
dog to a series of finger points?
She didn't appear to look then.
That time
she just went for the cheese.
Fi has quickly learned
that in this experiment,
the visual signal is irrelevant
for finding the food,
instead she chooses
to follow her nose.
What's interesting is what
the wolf's doing in the approach
because there's no doubt at all that
she's looking at Kathryn,
she can see her pointing.
But it seems that the nose wins over
the eye, because she's looking,
but ignoring what she's seeing.
But not what she's smelling.
The reason she's probably ignoring me
is because she's perfectly capable of
solving the problem without my help.
So she doesn't need to pay
attention to me.
So, visual information seems
to have a lower priority for wolves
than it does for dogs.
Wolves give greater emphasis
to smell.
Kathryn believes
she might have discovered why.
It's all about what happens
in the first few weeks of life.
You investigated this by raising
wolf cubs from that
very young age and contrasting
their behaviour with dogs.
I did, yeah,
so I actually hand-raised
both wolves and dogs.
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.
But as her wolf cubs developed,
Kathryn observed something
fascinating.
There's a brief window of time
soon after they are born
when the senses of both dogs
and wolves are set for life.
The window starts early for wolves,
at just two weeks old.
At this stage, only their sense
of smell has fully developed.
So, they can only understand
their world through smell.
But for dogs, this sensory window
starts at four weeks, a small,
but crucial, difference.
Because by then, dogs have developed
ALL of their senses.
When the dogs start
to explore their world,
they can use their vision,
they can use their smell
and they can use their sounds
all at the same time.
So, it seems that since the process
of domestication started,
the dogs have developed a greater
flexibility to involve
all of their senses and to be able
to prioritise more their vision
and their hearing than the wolves,
so you might argue that they're
a slightly more successful animal
when it comes to dealing
with people.
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.
So, wolves are hard-wired to trust
smell above all other senses.
But dogs use their senses
far more flexibly.
The senses have shaped both
these animals' minds.
They've helped define dogs and
wolves as very different animals.
So far, we've seen how animal minds
deal with sensory information
that's manageable.
But what happens if your mind is
being BOMBARDED by your senses?
Take these birds for example,
zipping around in the sky here.
For them and many other
flying animals, it's all about
economy of weight
and by necessity, therefore,
they have to have smaller brains
and that will have an impact on
how they perceive their world.
It will present its own very
peculiar challenges.
Birds on the wing can move in
any direction they choose.
But being able to fly brings with
it the constant risk of collision.
And what's more, their predators
in the air, like hawks,
can also attack from anywhere.
So bird brains need to take
in visual information
from every direction.
Their eyes 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
manoeuvres at 70kmph
within centimetres of buildings.
It's an incredible amount of
visual information to process...
all achieved with a tiny brain.
A swallow's brain weighs
around one gram -
a thousand times lighter than ours.
So how on earth do birds do it?
To find out, we've decided to carry
out a rather bizarre experiment.
It involves some
big, stripy boards...
..and some starlings.
You ready?
And to help, we've brought in
Martin Stevens -
an expert in animal senses.
It's looking beautiful.
Come on.
I'm hoping that this is going
to reveal how birds' brains
process the vast amounts of visual
information they need to handle.
Ready to go? Look at that.
What a splendid animal.
Too keen.
We weren't quite ready.
We like that. That's what
we like with our trial birds.
Martin, what's the plan?
What we're going to do to try
and understand how birds process
so much visual information,
is we're going to get him
to fly down this corridor.
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, so that it's a different
type of visual information,
and we'll see how
that changes things.
Well, it's quite dazzling as it is,
so let's see how he does.
We'll have to repeat
this several times
to get some precise timings,
I presume, but he's very keen.
So we can compare Arnie's
speed down the horizontal
and the vertical stripes.
He'll have to break the light beam
at the start...
..and again at the finish...
..to get a precise time for how
fast he flies down the corridor.
Did it work? Yes, that's successful.
Got a time. Excellent.
Come on, Arnie.
Good boy. Top work, top work.
Down you get. On the perch.
Yes, that worked. Yes? Excellent.
Arnie is performing admirably.
His flight times from one end of
the corridor to the other
are coming in at less
than two seconds.
Everything they do is quick.
Every motion is speedy. Yeah.
Good lad.
Excellent. Slightly faster.
Yes, that worked. Yes! Ten!
He's a champion.
Arnie's done well.
We've got timings for ten flights
through the horizontal stripes.
Now we're flipping
the stripes to vertical.
So, how will that affect
Arnie's speed?
OK, we're ready here. We're going
to repeat the whole thing
and contrast the results? Exactly.
Typical science. Fire up
the starlings, Lloyd. Let's go.
Arnie? Good boy.
Are you ready, Rose? Yep.
So we've started to get some
readings from the verticals.
Come on, there's a little
scrap there.
On you go. Look at that.
Beautiful. On you go.
The funny thing is that,
even to my eyes,
there's something very weird looking
about those vertical stripes.
Martin, I'm not sure about the
starlings, but looking down here,
this is certainly a far more
dazzling environment.
It's quite unpleasant, isn't it?
And Arnie seems to agree.
He's definitely not going as
direct as he was the first run.
No, definitely.
That was the slowest time so far.
Could Arnie really have slowed down?
The results are in and we can now
compare Arnie's flight times
through the horizontals
and the verticals.
OK, so we've got a
graph of the results.
First of all, we've got
the horizontal stripes,
which is the blue line here.
And then the red line shows how fast
it flew through the vertical stripes.
One thing that immediately strikes
me is that it's very clear that,
when it's flying through
the vertical stripes,
it never reaches the speed that
it did through the horizontals,
suggesting to me that it was
easier for it to fly down here
when the stripes were horizontal.
That's right, and it comes down to
a neat trick called optic flow.
And that really relates to how
much information passes over
the eye as the animal is moving.
Optic flow is a way the bird brain
processes visual information
so that it isn't overwhelmed.
It filters out nonessential detail,
so the bird perceives
simple patterns.
When Arnie flies through
horizontal stripes,
that pattern changes very little.
He perceives the lines as a distant
horizon, so it's safe to fly fast.
The vertical stripes on the other
hand, those stripes are passing over
the eye really rapidly
and changing very fast,
and that's simulating a situation
where there might be lot
of objects very close to the bird,
and so it has to slow down
to avoid the risk of collisions.
So when Arnie flies through
the vertical stripes,
the pattern changes constantly and
he perceives it as nearby obstacles.
This makes him fly cautiously -
almost a metre per second slower.
The bird's mind has evolved
an elegant way
to know how fast it's safe to fly.
C'mon, Arnie.
It's always fantastic
to learn something new,
and I've been watching
birds for years now,
and I've always wondered,
how do they fly through such
cluttered environments
without ever bumping into things?
And it's all about
filtering information,
not overloading their
little bird brains.
Every time I look at a new animal,
I am constantly surprised by the
sheer power of their senses...
..and the ingenious
ways that they use them.
Some species seem to be able to
interpret that sensory information
to understand almost everything
about the world around them.
But there is one thing
that I've always wondered.
Can they use those senses to
go beyond this, the physical world,
and grasp abstract
concepts like we do?
Things like time, for example.
For humans, time is a concept.
To keep a close track of it,
we depend on clocks.
But can animals use their
senses to understand time?
To try to find out, I'm going
to test an old myth about dogs -
that they can tell exactly when
their owner is about to return home.
Meet the owners of Jazz,
the Hungarian Viszla.
Now, they're convinced
that Jazz knows exactly
when his master, Johnny,
is about to come home.
And to witness this,
we've 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 evening, Christine
comes home at four o'clock.
But it's what Jazz does
next that really interests us.
You see, every evening
at around 4:40,
20 minutes or so 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 four and five, Jazz
is always looking out for Johnny.
It seems Jazz somehow
knows that Johnny's coming home.
And it's a claim
made by many dog owners.
But how does Jazz do it?
Now it could just be that
Christine coming home
sets Jazz's clock.
We know it's not because he needs
dinner or his walkies,
because Christine's dealt with that.
There is 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
fades at a regular rate.
So could it be that
when Johnny's scent
drops to a particular level,
Jazz senses he's about to return?
To test this theory, at the end
of the week, we made a change.
On her way home, Christine swung
by Johnny's football club to get
some of his freshly worn t-shirts.
And then, when she got back at her
usual time, she wafted them
around the living room to
spread Johnny's smell around.
If Jazz is using the fading smell
of Johnny
to sense the passage of time,
then this should be the equivalent
of re-setting the clock.
So will Jazz still know
what time it is?
It's now less than half an hour
before Johnny normally comes home,
but for the first time,
Jazz stays dozing.
It's now 4:48.
Jazz only lifted his head
for about 30 seconds.
He's lying flat out again, enjoying
the heat at the radiator.
Now Johnny's back...
Are you coming a walk?
..and to Jazz, it seems to come as
a complete surprise.
Now, let's not pretend
that this is scientific.
There could be any number of
things that Jazz is reacting to.
But it's an intriguing
idea that dogs' sense of smell
might allow them to grasp something
as abstract as time -
a concept that we tend to assume
only the human mind can understand.
So how could an animal's mind
take in information from the senses,
and draw from it an understanding
of something
that's not physically present?
Well, now, for the first time,
we are beginning to uncover
what might be happening
inside their brains.
In Atlanta, neuroscientist
Greg Berns is adapting a harmless
medical technique to study
brain activity in dogs.
OK, 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 like,
but with a few tricks, we can do
what's called functional MRI
which looks at brain activity,
and, by analysing 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 - not
a good way to study their brains.
One, two, three, steps!
But Greg has teamed up with
Mark Spivak to devise a programme
to train dogs for the bizarre
conditions they'll face.
The key 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.
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 painless and it does no harm.
It's at the very cutting edge
of animal science.
And it's beginning to give us
some fascinating insights.
Patricia, we're going to begin the
first scan with the localiser.
Are you ready?
One of Greg's earliest experiments
is revealing important clues
as to what happens in a dog's brain
when it receives
information from its senses.
First, he's looking at
a visual signal.
So Kady's in the scanner right now
and Patricia's actually giving
Kady hand signals.
We've already taught the dogs through
lots of practice
that this means food.
OK? So every time Patricia
makes this signal,
we're going to be looking in her
brain, what that 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 show 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
that they might have responded
completely differently, but that
doesn't seem to be the case.
And when you think about what
this requires the dog to do,
it reveals a complex
chain of thought.
The results are showing that dogs,
and probably most animals,
have brains and minds that
are far more sophisticated
than we ever gave them credit for.
These are remarkable
and tantalizing insights.
Yet, so far in this programme,
we've been exploring how the animal
mind is shaped by the senses
we ourselves possess.
Vision...
hearing...
smell...
taste...
and touch.
But these are not the only
senses in the natural world.
Out here, there are other physical
forces that we simply haven't
evolved the ability
to be able to detect.
So what I want to do now is take
a look at a group of animals
that go beyond these
five senses that we know,
to perceive the world in a way
that would be entirely alien to us.
To do that, I've come to the
island of Bimini in the Bahamas.
It's a hot-spot for an animal
that's always fascinated me.
With me is scientist Eric Stroud.
He's spent years studying sharks.
Sharks are extremely
successful predators.
They can smell tiny quantities
of blood over huge distances
and follow minuscule vibrations
of their prey in the water.
But the shark sense that I want to
investigate is very different.
It's one that we humans have no
experience of at all.
Try and push them into here, yeah?
If you can get him against the
fence, you have a better shot.
Eric is going to demonstrate that
sense with a strange experiment.
But first, we need our baby
lemon shark to stay nice and still.
OK, got him. Look at that!
OK, so we're going to roll it over
and place it into tonic immobility.
Tonic immobility?
Go on, explain that one.
No-one's really sure why it happens,
but when the sharks are inverted
like this, they kinda go to sleep.
Wow. It's just relaxed.
It's like yoga for sharks.
Indeed. And there's nothing to
suggest that it's stressed.
I'm barely holding it.
I'm going to hand him to do you, OK?
Just put your thumbs
behind there and hold...
OK, ready? These things obviously
can bite. What would be the damage?
A laceration, at this age.
You might need stitches, actually,
from this little shark.
So, if anything goes wrong,
just let it go.
Let's do our experiment.
Eric's experimental kit
is really simple.
Steel spoon and a magnet. Thanks.
I've been left holding the shark!
I'm not sure whether that's an
enviable position to be in or not.
We have a strong magnet here we're
going to use for the experiment,
and it's a pretty powerful magnet.
It'll attract the spoon
out of my hand.
Eric wants to show me how
our shark reacts to the magnet.
So what we're going to do is put
a blinder by the shark's eye
so he can't see what I'm doing.
So the shark won't be able
see the magnet coming.
OK, I'm going to put a blinder here.
But will he sense it?
I'm approaching...
That was a reaction!
Wow, he jumped out of your hands.
He did.
Our little shark is
completely unharmed,
but he's acutely sensitive
to Eric's magnet.
Why?
Well, it's down to a
clever 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 jelly-filled
tubes that can detect
the voltage difference between
the tube's opening and its base.
They are exquisitely sensitive,
able to pick up
billionths of a volt.
Biologically, we humans
have no mechanism like this.
To us, the ability is
completely alien.
But why would a shark need
such a sense?
It helps them to find food.
It's predation.
They can locate the heartbeat of a
crab or stingray underneath the sand.
When that animal is
beating or moving,
the muscles generate a very
weak electromagnetic field,
and that's what their noses
are gearing in on.
We're, in a sense, simulating that.
The movement of the magnet
across the shark's nose
induces that electromagnetic current,
but we're just doing it many times
greater than a stingray or a crab.
So, it's sensory overload. Exactly.
Hence the struggle. Exactly.
At low levels, this sense allows
sharks to find their prey.
But at high levels, it repels them,
just as we need light to see,
yet would recoil from
dazzling headlights.
But is this effect powerful enough
to change a shark's behaviour?
We're heading from Bimini to
Triangle Rock -
a well-known gathering place
for large Caribbean reef sharks.
We've been joined by
marine biologist Pat Rice.
We're going to pit
a shark's magnetic sense
against what must surely be their
most powerful instinct -
their urge to eat.
Here they are. Look!
Caribbean reef sharks.
Slap it on the water.
Beautiful sharks, aren't they?
They're stunning.
Absolutely stunning, aren't they?
So, they're here. Let's get going.
Stunning they may be,
but to do the experiment,
I'm going to have to jump
in with that lot.
I know they're only two metres,
but they look a little bit bigger
than I imagine a two metre shark.
Maybe it's the water.
Maybe it's acting as a lens
and exaggerating their length.
Pat now needs to set up
the experiment
eight metres down on the sea bed.
What we're going to do here
is perform a very simple,
but hopefully effective, experiment.
And what I've got in my hand here
is an extremely powerful magnet.
That's why I'm not coming too close
to the camera or you will never
see this, it'll wipe
everything in there.
And we're going to make a circle
of these magnets on the bottom,
and in the centre of that circle,
we're going to place some food.
On the sea floor, Pat and safety
diver Vincent are setting up
the circle of magnets,
into which we'll put our bait.
We need to be sure
the sharks aren't simply
deterred by a circle of
black objects, so Pat's made
a second circle of ordinary
bricks covered in black tape.
We'll put bait in the two circles
and see what happens.
The magnets are powerful,
but will they repel the sharks?
Essentially, what we're trying to
test here is whether the sharks'
sensitivity to these magnets will
overcome their desire to feed.
Time for me to join Pat -
and a whole load of sharks.
Jump!
I'm told the sharks in this spot
have never yet attacked a human.
But to do this experiment,
we need to deliberately
tempt them in very close.
We've arrived on the bottom.
On this side is the ring of bricks -
the placebo, if you like.
And here on this side
is the ring of magnets.
And now what we've got to do
is introduce the bait.
OK, we've got sharks here already.
They're coming in.
Pat's got some bait here,
some tasty tuna.
We're going to try and fix this in
the centre of each of the circles.
We're in the water with
hungry sharks,
and in our bare hands,
we've got some fish.
This is like a peculiar game of
Russian roulette, isn't it?
All of those sharks up by the
boat will now be able to smell
the bait down here with us.
Here comes a shark now.
It's bypassed the magnets...
and it's gone
straight into the brick circle
and it's taken the bait.
Now there's no bait in the bricks,
will they show an interest
in the bait in the magnet circle?
Look at that! It turned as
if it could sense that bait,
and it turned away.
It can tell there's food there.
It must be able to see all
of the other fish currently
feasting on it but it wouldn't
go inside that ring of magnets.
Time to put fresh
bait in the bricks.
And I've barely had
a chance to retreat
when a shark makes
straight for the brick circle again.
Look at that.
It's a monstrous great animal.
But so far they haven't touched
the bait in the magnets.
It's 2-0.
It tweaked them
and definitely flinched away.
And yet, they're clearly hungry.
Not me. No, not me...
We're down to our last piece
of bait for the brick circle...
and it doesn't last long.
It's snaffled the
food from the brick circle.
But there's no doubt the magnets
are repelling the sharks.
It seems almost confused
by those magnets.
And the bait remains in the circle.
Although undetectable by us,
in the sharks' mind, our magnetic
force-field is overwhelming.
So strong, it even overrides
the shark's primal urge to feed.
This exploration of animal senses
has been a first
and a fascinating insight
into the animal mind,
and I've been surprised.
The way that they experience
and understand their world
is far more sophisticated
than I would have imagined.
But above all,
I've learned that it's the animal
senses that shape the animal mind.
It's those senses that
make every single species,
including our own,
unique and special.
Next, we'll be meeting the
animals with the most powerful
problem-solving minds on the planet.
How on earth did that crow do that?
We'll find out how apparently
simple animals can crack problems
that would baffle humans...
..and pit them against other animals
I'd like to think of as clever.
All you've got to do
is lift the ball!
watching animals.
And there's one question that
obsesses me.
What's it like being an animal?
This is Itchy
and Scratchy. I've had them
since they were 6 weeks old,
I've raised them, I love them
so much and just like all dog owners
I sometimes gaze into these
little chestnut eyes and wonder -
what's going on inside that head?
And you know, I would give
anything to be another
animal for just five minutes,
to be able to experience the world
the way they perceive it, to know
what they're thinking.
To be INSIDE the animal mind.
It's one of the great
mysteries of the natural world
and now, new research is
starting to give answers.
Wow.
In this series,
I'm going to seek out
the most powerful
animal minds on the planet
and find out
what they're capable of.
Look at that!
If I'm really going to get
inside the minds of other animals,
the first thing
I need to do is to discover how
they experience the world
around them.
I mean, imagine how different this
world is to my dogs.
To them, this is a landscape
of smell.
We both live in the same world
but we experience it in completely
different ways.
In this first programme
we'll investigate
the sensory secrets of the animal
we know best of all.
Close your eyes.
Dogs.
Aww, what happened?!
And test them
against their ancient ancestors.
We'll be discovering how the
minds of very different animals
perceive their world
through their senses.
And I'll come face-to-face
with an animal that
most people wouldn't want to meet in
their nightmares as I learn about
the remarkable sixth sense of
sharks.
Animal senses define the way
they think.
They're the gateway
to the animal mind.
Castlewellan Lake
in Northern Ireland.
I've come to its rain-swept
shores to see a dog do something
that I thought impossible.
Now, obviously, Itchy and Scratchy
have got a pretty
good pair of noses.
But what I've always wondered is
just how good is the dog's
sense of smell?
Well, today we're going to put
the dog's nose to the ultimate test.
Neil Powell trains sniffer dogs.
And one of his top
performers is Fern.
Now, Fern usually works for the
Search and Rescue Dog Association.
But today, she's going to try and
sniff out something
that Neil has hidden.
What's extraordinary is that
it's not on dry land.
It's in the lake.
It's underwater.
Here she is, Fern.
Looking keen and all dressed up.
What type of spaniel is she?
She's a mixture between
Cocker and Springer Spaniel.
So, she's known as a sprocker.
A sprocker.
Now, let's get this straight.
You've already been out this morning
and you've hidden a lure
IN the lake?
And we're going to go out
and she's going to sniff it? Yeah.
And find it?
Yes, what we've done is,
about two hours ago we hid a small
canister in 20 feet of water.
It's got some pork meat in it.
I know where it is but she doesn't,
so we're going to search the lake now
with her and, hopefully,
we'll get to
within about 30 feet of it.
Come in then, Fern. Let's go for it.
I really do need to see this.
Can a dog really smell
something on the bottom of a lake,
in driving rain and strong winds?
Sounds improbable.
Neil and the dive team know
precisely where the canister
is hidden because they fixed
a GPS position on it
when they dropped it into the lake.
The question is, can Fern find it?
Of course, this isn't a stunt that
Neil and Fern pull off
for the joy of it, she's been
trained to detect bodies that have
come to rest
beneath the surface of the water,
there's a very serious side to this.
Nevertheless, it's pretty
counterintuitive, isn't it?
Here we're asking a dog
to smell through six metres,
20 feet of water.
And when you think about it, in all
those movies and cop shows
we've always watched,
when the criminal's fleeing,
they run up the stream
so they don't leave any scent
because the dogs can't sniff them.
Well - criminals, if you're
watching this,
you might have to think again.
The team's technique is to
systematically crisscross the lake.
So, at some point,
Fern will find herself directly
downwind of the sunken canister.
But will she pick up the scent?
The lake is a mile long
and half a mile wide.
And only the tiniest quantities
of chemicals from the meat
might reach the surface.
And of that minute trace, almost
all of it will get blown away.
And yet, around ten minutes
after we start...
..Fern senses something.
That's the scent.
Turn it up to the wind, John.
We start circling,
narrowing down the location.
She's got the scent,
how are you going to know when we're
in the closest possible spot?
When she arrives over the top of it
you'll see her going over
the side a little bit more and she's
really focused on the water.
You're getting her right into the...
see, there, see that? Yeah.
Bring her round there, John.
Right round, John.
I'd put her there, John.
Fern has made it quite clear
where she thinks
the source of the smell is.
Fern is confident which in turn
means Neil is very confident
and they've dropped the marker in
and the thought is that we
could be within just a few
metres of where the lure is hidden.
But the one thing I will say is I'm
sat here as any other human being
would be, with no sense
at all, using a sense
of smell that we are in the right
place. All I can smell is a
slightly fresh, rainy, damp,
very pleasant afternoon
in Northern Ireland.
There's only one way to know
if Fern's chosen the correct spot -
The dive team check
it against the GPS fix they took
when they threw
the canister into the water.
And, unbelievably,
Fern is bang on top of it.
The divers' final job is to
retrieve the canister.
But the lake bed has a surprise.
The bottom is a metre of soft silt
and the canister has sunk
right into it.
So, amazingly, Fern hasn't just
sniffed the lure through
six metres of water but also through
a metre of mud as well.
What an absolutely
astonishing thing.
Now, I've seen animals over the
years pull off some remarkable feats
but this has been something
else, it really has.
There ye go, what a clever girl.
Good girl. Clever girl
'And the reward for all her efforts?
Just an old tennis ball.'
Fern's training might give her
this special ability.
But all dogs have an extremely
powerful nose.
They can smell in parts per
trillion, the equivalent of being
able to taste a spoonful of sugar
in two Olympic-size swimming pools.
So, how on earth can dogs do this?
Well, it's all down to a nose
that's nothing like ours.
Each nostril can be controlled
independently, allowing dogs
to detect precisely the direction
a smell is coming from.
And what goes on inside
is even more impressive.
You see, dogs split the flow of air
into two separate streams,
one for breathing
and one for smelling.
So they can do
both at the same time.
It's a superb tool for gathering
sensory information and it means
a dog's mind understands the world
in a completely different way to us.
Their world is a complex smellscape
in which they can sniff out
an animal that's too far off to see.
Or pick up the tiniest
trace of odour left on a leaf.
But although smell is vastly more
powerful for dogs than it is
for us, it's one of the five
senses that we share
with them and most other animals.
And there's a reason for that.
The senses are the front line
in the way that animals interact
with the physical world around them
and this goes a long to explain how
those senses actually work.
Whatever kind of animal you are,
you experience the same
physical properties.
I need vision to see light
bouncing off objects -
I need touch to feel surfaces
and sense temperature.
I need to smell
and taste chemical substances.
And I need hearing to detect
shockwaves in the air.
These are my five basic senses to
guide me through the world.
Perhaps it's not surprising that
I share these with the
vast majority of other animal
species in some combination or other
for the very simple reason that we
all inhabit the same physical world.
And yet - those five familiar
senses can be used by
some animals in ways that are
totally foreign to the human mind.
I've come to the Dolphin Research
Centre in Florida to see
something that dolphins can do
with their sense of hearing.
Now, it's hard to study
dolphins in the open ocean.
But keeping them in captivity is
controversial.
And since 1988, aquariums in the
United States
don't take dolphins from the wild.
Dolphins like Tanner were
born in captivity.
Tanner, are you ready?
No? Yes, you are ready.
Researchers Armando
and Wade want to show me
an ingenious experiment to
demonstrate how Tanner uses sound.
I have a list of behaviours
right here now, I can't see them,
please don't show them to me...
I'm going to select
an action from a list for Wade to
perform in the water.
Wade, go ahead in.
I'm only showing Wade,
Armando and Tanner have no idea
which one he's about to do.
OK, Wade, let's go for this one,
please? OK?
Tanner, imitate.
'With his eyes covered, Tanner will
now attempt to imitate Wade.'
Then the other one will go on the
left eye, but I have to give him
the signal first, which means
imitate.
Are you ready?
Imitate...
'So, will Tanner know what
Wade is doing?'
There he goes, Wade is upside down
and Tanner is upside down as well.
'OK. That's one out of one.
'But for something this bizarre,
I need a little more proof.'
Shall we try another?
Try another one?
Let me put the eyecup on.
Let's go for this one, Wade...
And here we go...
'Tanner appears to take a moment to
listen before imitating
'Wade's exact movements.'
It's pretty impressive,
I have to say.
'And for the piece
de resistance, the bob.'
Next word...
Now, watch. He's reading.
He's reading, without
a shred of a doubt.
He's reading without seeing.
There's no question of that,
and getting it right.
Good boy, Tanner. Thank you very
much, thank you. Excellent!
Tanner, you're the best.
'So, how does Tanner do it?'
Scientists believe he's using
sound in an unusual way.
It's called echolocation.
A specialised
fat-filled organ called
the melon behind the forehead emits
focused pulses of sound.
But the key to echolocation is
listening to the
echoes of those sound
waves as they come back.
Dolphins pick up and amplify those
returning waves with
a cavity in their jaw, before
sending them on to the inner ear.
They use echolocation to hunt down
and pinpoint their prey
even in darkness.
Dolphins share this use of hearing
with nocturnal animals like bats.
But just how detailed
a picture of their world can
they build up in their mind,
using this one sense?
When we hear that burst of sound
being pumped out by the dolphins
it's no more than a rapid cacophony
of random clicks as far as
we're concerned,
but this I think will
surprise you, because if we process
the return echo simply by slowing
it down, this is what we can hear.
This is a return echo
from an Atlantic cod, whilst this...
..is what's bouncing back to
the dolphin from a mullet,
so clearly for the dolphin it's
a very sensitive sense, it can
tell the difference between these
two different species of fish,
perhaps even choosing which one
it wants to eat.
The dolphin's echolocation is
an extremely powerful sensory tool
which allows its mind to build
up a picture of the world.
But at the moment I'm left thinking,
what does a dolphin actually
do mentally? What does it think
with all of that echolocation?
Does it turn it into a visual image?
We don't know, we may never know.
But one thing I'm sure of is
that this will have
a profound effect on the way that
these animals think.
Countless other animals use their
five senses in ways which,
to us, are unfamiliar.
Starfish see, but not as we do.
A basic eye at the end of each limb
can form simple images,
helping them find their way
back to their feeding grounds.
Butterflies and moths have no nose.
But their sense of smell is many
times more sensitive than
even a dog's.
And it's thanks to their antennae.
In some species the antennae can
respond to only a few
molecules of scent
from a potential mate.
When I was a kid we called them
"feelers"
but they're actually being
used for smelling.
Across the animal world, species
evolve the senses which give them
the best chance of surviving
in the environment where they live.
But very often, individual species
or groups of species will form
a sort of a sensory hierarchy in
that one or two senses will become
far more sensitive than the others.
So, if two animals have
a different dominant sense,
how far does that influence
the way that they think?
I've come to Wolf Park in Indiana,
to find out.
Scientists here are studying
a group of ten wolves
that roam over
a territory of a dozen acres.
Wolves are fascinating
because, biologically,
they are the same as dogs.
Around 10,000 years ago, humans
began domesticating some wolves,
and over time they created dogs.
Now, wolves haven't changed
much in that time.
Dogs, on the other hand,
have evolved into an astonishing
variety of breeds.
They look very different
to wolves.
But how differently
do their minds work?
To give us some insight,
we're going to test dogs
and wolves in a battle
of the senses.
So first, I want to establish
the sensory abilities
these two animals share,
starting with smell.
This couple of wolves down here
are about, I don't know, 60m away
and I'm going to test that
sense of smell.
They've got expensive tastes, these
animals, because what I'm going
to use is this, Chanel No 5.
It's said that they have
a real craving for it.
So, I'm just going to sneak down
here...
..put some of this on the grass...
..and see what happens.
Well, there goes a tenner, at least,
let's see what happens.
But it's not so much picking up
that scent, it's what they do
when they find it that we're
interested in.
Nose is up.
Yes...
Look at that...
This is what we call scent rolling
and I'm afraid to say that
many of you have probably seen
your dogs doing this
in less pleasant things than
expensive perfume.
It's brilliant, isn't it?
On the face of it, it seems that
dogs and wolves live in the
same sensory world and it's a world
dominated by the sense of smell.
Let's go!
But that's not the only sense
that's important to dogs.
Let's go.
Any dog owner knows they
watch us closely with their eyes.
So, what role does vision play in
how dogs understand the world?
Dr Brian Hare has recruited
dog owners from across the US
to carry out
some simple tests that show how
they use visual information.
OK, Sisu, stay.
OK. One of the simplest is called
the Pointing Test.
And now watch where her gaze goes.
Right at me. Stay.
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 at 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 smell equally appetising.
So, there's only one reason for Sisu
to choose between them.
OK, Sisu, you ready?
This. OK, Sisu.
It's the visual signal that
Brian is giving her.
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.
Hey. OK, 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 telling her
something, she's much more
happy to use that information
than to rely on her nose.
Most dog owners will be familiar
with this ability.
OK, Kai. Dogs will readily follow
visual information.
Callie, is it there? But we also know
they have great noses.
So, which sense do dogs trust
the most - vision or smell?
In a new test, 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 shift where it's hidden and move
it to the other location.
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.
Look at that face.
You're killing me.
All right, Dexter,
are you ready, buddy?
OK, that's where it's going to be.
This time there's food
under only one cup.
OK. Now close your eyes.
And without Dexter seeing,
Brian's now moving that
food to the other cup.
Poor Dexter's senses are in
direct conflict.
So, does he trust his eyes
or follow his nose?
OK, Dexter, find it!
Aww, what happened? It's a trick!
It's over here, it was a trick!
Are you ready, Dexter?
OK, we're going to put it over here.
Here it is.
Now, close your eyes.
OK, Dexter, go get it.
Again and again, Dexter, like most
dogs, goes not to where
he can smell the food but where
he SAW the food.
OK, Dexter, get it!
Awww!
It tends to be that
if they have visual information
they prioritise that, they actually
put that in front of what
information they might be
getting from their nose.
But what about wolves?
Do they prioritise their senses
in the same way?
Well, back at Wolf Park,
we're going to test them.
Kathryn Lord from the University
of Massachusetts
reared this group of wolves
from birth and they're
certainly familiar with humans.
I know, I'm going to stand up
for a second
cos you're getting a little
excited, I know.
So, this grey wolf Fi can understand
certain types of information
that a wild wolf wouldn't.
She comes when her name is called.
Fi!
And, remarkably, Fi can also follow
Kathryn's pointing.
She's just as capable as any dog
of understanding what it means.
Hey.
We've seen that dogs trust this
visual signal above smell.
So is this also true of wolves?
To find out, we're going to repeat
the finger pointing test
several times,
just as we did with the dogs,
with a snack under each can.
Fi!
So, will Fi the wolf respond like a
dog to a series of finger points?
She didn't appear to look then.
That time
she just went for the cheese.
Fi has quickly learned
that in this experiment,
the visual signal is irrelevant
for finding the food,
instead she chooses
to follow her nose.
What's interesting is what
the wolf's doing in the approach
because there's no doubt at all that
she's looking at Kathryn,
she can see her pointing.
But it seems that the nose wins over
the eye, because she's looking,
but ignoring what she's seeing.
But not what she's smelling.
The reason she's probably ignoring me
is because she's perfectly capable of
solving the problem without my help.
So she doesn't need to pay
attention to me.
So, visual information seems
to have a lower priority for wolves
than it does for dogs.
Wolves give greater emphasis
to smell.
Kathryn believes
she might have discovered why.
It's all about what happens
in the first few weeks of life.
You investigated this by raising
wolf cubs from that
very young age and contrasting
their behaviour with dogs.
I did, yeah,
so I actually hand-raised
both wolves and dogs.
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.
But as her wolf cubs developed,
Kathryn observed something
fascinating.
There's a brief window of time
soon after they are born
when the senses of both dogs
and wolves are set for life.
The window starts early for wolves,
at just two weeks old.
At this stage, only their sense
of smell has fully developed.
So, they can only understand
their world through smell.
But for dogs, this sensory window
starts at four weeks, a small,
but crucial, difference.
Because by then, dogs have developed
ALL of their senses.
When the dogs start
to explore their world,
they can use their vision,
they can use their smell
and they can use their sounds
all at the same time.
So, it seems that since the process
of domestication started,
the dogs have developed a greater
flexibility to involve
all of their senses and to be able
to prioritise more their vision
and their hearing than the wolves,
so you might argue that they're
a slightly more successful animal
when it comes to dealing
with people.
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.
So, wolves are hard-wired to trust
smell above all other senses.
But dogs use their senses
far more flexibly.
The senses have shaped both
these animals' minds.
They've helped define dogs and
wolves as very different animals.
So far, we've seen how animal minds
deal with sensory information
that's manageable.
But what happens if your mind is
being BOMBARDED by your senses?
Take these birds for example,
zipping around in the sky here.
For them and many other
flying animals, it's all about
economy of weight
and by necessity, therefore,
they have to have smaller brains
and that will have an impact on
how they perceive their world.
It will present its own very
peculiar challenges.
Birds on the wing can move in
any direction they choose.
But being able to fly brings with
it the constant risk of collision.
And what's more, their predators
in the air, like hawks,
can also attack from anywhere.
So bird brains need to take
in visual information
from every direction.
Their eyes 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
manoeuvres at 70kmph
within centimetres of buildings.
It's an incredible amount of
visual information to process...
all achieved with a tiny brain.
A swallow's brain weighs
around one gram -
a thousand times lighter than ours.
So how on earth do birds do it?
To find out, we've decided to carry
out a rather bizarre experiment.
It involves some
big, stripy boards...
..and some starlings.
You ready?
And to help, we've brought in
Martin Stevens -
an expert in animal senses.
It's looking beautiful.
Come on.
I'm hoping that this is going
to reveal how birds' brains
process the vast amounts of visual
information they need to handle.
Ready to go? Look at that.
What a splendid animal.
Too keen.
We weren't quite ready.
We like that. That's what
we like with our trial birds.
Martin, what's the plan?
What we're going to do to try
and understand how birds process
so much visual information,
is we're going to get him
to fly down this corridor.
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, so that it's a different
type of visual information,
and we'll see how
that changes things.
Well, it's quite dazzling as it is,
so let's see how he does.
We'll have to repeat
this several times
to get some precise timings,
I presume, but he's very keen.
So we can compare Arnie's
speed down the horizontal
and the vertical stripes.
He'll have to break the light beam
at the start...
..and again at the finish...
..to get a precise time for how
fast he flies down the corridor.
Did it work? Yes, that's successful.
Got a time. Excellent.
Come on, Arnie.
Good boy. Top work, top work.
Down you get. On the perch.
Yes, that worked. Yes? Excellent.
Arnie is performing admirably.
His flight times from one end of
the corridor to the other
are coming in at less
than two seconds.
Everything they do is quick.
Every motion is speedy. Yeah.
Good lad.
Excellent. Slightly faster.
Yes, that worked. Yes! Ten!
He's a champion.
Arnie's done well.
We've got timings for ten flights
through the horizontal stripes.
Now we're flipping
the stripes to vertical.
So, how will that affect
Arnie's speed?
OK, we're ready here. We're going
to repeat the whole thing
and contrast the results? Exactly.
Typical science. Fire up
the starlings, Lloyd. Let's go.
Arnie? Good boy.
Are you ready, Rose? Yep.
So we've started to get some
readings from the verticals.
Come on, there's a little
scrap there.
On you go. Look at that.
Beautiful. On you go.
The funny thing is that,
even to my eyes,
there's something very weird looking
about those vertical stripes.
Martin, I'm not sure about the
starlings, but looking down here,
this is certainly a far more
dazzling environment.
It's quite unpleasant, isn't it?
And Arnie seems to agree.
He's definitely not going as
direct as he was the first run.
No, definitely.
That was the slowest time so far.
Could Arnie really have slowed down?
The results are in and we can now
compare Arnie's flight times
through the horizontals
and the verticals.
OK, so we've got a
graph of the results.
First of all, we've got
the horizontal stripes,
which is the blue line here.
And then the red line shows how fast
it flew through the vertical stripes.
One thing that immediately strikes
me is that it's very clear that,
when it's flying through
the vertical stripes,
it never reaches the speed that
it did through the horizontals,
suggesting to me that it was
easier for it to fly down here
when the stripes were horizontal.
That's right, and it comes down to
a neat trick called optic flow.
And that really relates to how
much information passes over
the eye as the animal is moving.
Optic flow is a way the bird brain
processes visual information
so that it isn't overwhelmed.
It filters out nonessential detail,
so the bird perceives
simple patterns.
When Arnie flies through
horizontal stripes,
that pattern changes very little.
He perceives the lines as a distant
horizon, so it's safe to fly fast.
The vertical stripes on the other
hand, those stripes are passing over
the eye really rapidly
and changing very fast,
and that's simulating a situation
where there might be lot
of objects very close to the bird,
and so it has to slow down
to avoid the risk of collisions.
So when Arnie flies through
the vertical stripes,
the pattern changes constantly and
he perceives it as nearby obstacles.
This makes him fly cautiously -
almost a metre per second slower.
The bird's mind has evolved
an elegant way
to know how fast it's safe to fly.
C'mon, Arnie.
It's always fantastic
to learn something new,
and I've been watching
birds for years now,
and I've always wondered,
how do they fly through such
cluttered environments
without ever bumping into things?
And it's all about
filtering information,
not overloading their
little bird brains.
Every time I look at a new animal,
I am constantly surprised by the
sheer power of their senses...
..and the ingenious
ways that they use them.
Some species seem to be able to
interpret that sensory information
to understand almost everything
about the world around them.
But there is one thing
that I've always wondered.
Can they use those senses to
go beyond this, the physical world,
and grasp abstract
concepts like we do?
Things like time, for example.
For humans, time is a concept.
To keep a close track of it,
we depend on clocks.
But can animals use their
senses to understand time?
To try to find out, I'm going
to test an old myth about dogs -
that they can tell exactly when
their owner is about to return home.
Meet the owners of Jazz,
the Hungarian Viszla.
Now, they're convinced
that Jazz knows exactly
when his master, Johnny,
is about to come home.
And to witness this,
we've 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 evening, Christine
comes home at four o'clock.
But it's what Jazz does
next that really interests us.
You see, every evening
at around 4:40,
20 minutes or so 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 four and five, Jazz
is always looking out for Johnny.
It seems Jazz somehow
knows that Johnny's coming home.
And it's a claim
made by many dog owners.
But how does Jazz do it?
Now it could just be that
Christine coming home
sets Jazz's clock.
We know it's not because he needs
dinner or his walkies,
because Christine's dealt with that.
There is 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
fades at a regular rate.
So could it be that
when Johnny's scent
drops to a particular level,
Jazz senses he's about to return?
To test this theory, at the end
of the week, we made a change.
On her way home, Christine swung
by Johnny's football club to get
some of his freshly worn t-shirts.
And then, when she got back at her
usual time, she wafted them
around the living room to
spread Johnny's smell around.
If Jazz is using the fading smell
of Johnny
to sense the passage of time,
then this should be the equivalent
of re-setting the clock.
So will Jazz still know
what time it is?
It's now less than half an hour
before Johnny normally comes home,
but for the first time,
Jazz stays dozing.
It's now 4:48.
Jazz only lifted his head
for about 30 seconds.
He's lying flat out again, enjoying
the heat at the radiator.
Now Johnny's back...
Are you coming a walk?
..and to Jazz, it seems to come as
a complete surprise.
Now, let's not pretend
that this is scientific.
There could be any number of
things that Jazz is reacting to.
But it's an intriguing
idea that dogs' sense of smell
might allow them to grasp something
as abstract as time -
a concept that we tend to assume
only the human mind can understand.
So how could an animal's mind
take in information from the senses,
and draw from it an understanding
of something
that's not physically present?
Well, now, for the first time,
we are beginning to uncover
what might be happening
inside their brains.
In Atlanta, neuroscientist
Greg Berns is adapting a harmless
medical technique to study
brain activity in dogs.
OK, 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 like,
but with a few tricks, we can do
what's called functional MRI
which looks at brain activity,
and, by analysing 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 - not
a good way to study their brains.
One, two, three, steps!
But Greg has teamed up with
Mark Spivak to devise a programme
to train dogs for the bizarre
conditions they'll face.
The key 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.
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 painless and it does no harm.
It's at the very cutting edge
of animal science.
And it's beginning to give us
some fascinating insights.
Patricia, we're going to begin the
first scan with the localiser.
Are you ready?
One of Greg's earliest experiments
is revealing important clues
as to what happens in a dog's brain
when it receives
information from its senses.
First, he's looking at
a visual signal.
So Kady's in the scanner right now
and Patricia's actually giving
Kady hand signals.
We've already taught the dogs through
lots of practice
that this means food.
OK? So every time Patricia
makes this signal,
we're going to be looking in her
brain, what that 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 show 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
that they might have responded
completely differently, but that
doesn't seem to be the case.
And when you think about what
this requires the dog to do,
it reveals a complex
chain of thought.
The results are showing that dogs,
and probably most animals,
have brains and minds that
are far more sophisticated
than we ever gave them credit for.
These are remarkable
and tantalizing insights.
Yet, so far in this programme,
we've been exploring how the animal
mind is shaped by the senses
we ourselves possess.
Vision...
hearing...
smell...
taste...
and touch.
But these are not the only
senses in the natural world.
Out here, there are other physical
forces that we simply haven't
evolved the ability
to be able to detect.
So what I want to do now is take
a look at a group of animals
that go beyond these
five senses that we know,
to perceive the world in a way
that would be entirely alien to us.
To do that, I've come to the
island of Bimini in the Bahamas.
It's a hot-spot for an animal
that's always fascinated me.
With me is scientist Eric Stroud.
He's spent years studying sharks.
Sharks are extremely
successful predators.
They can smell tiny quantities
of blood over huge distances
and follow minuscule vibrations
of their prey in the water.
But the shark sense that I want to
investigate is very different.
It's one that we humans have no
experience of at all.
Try and push them into here, yeah?
If you can get him against the
fence, you have a better shot.
Eric is going to demonstrate that
sense with a strange experiment.
But first, we need our baby
lemon shark to stay nice and still.
OK, got him. Look at that!
OK, so we're going to roll it over
and place it into tonic immobility.
Tonic immobility?
Go on, explain that one.
No-one's really sure why it happens,
but when the sharks are inverted
like this, they kinda go to sleep.
Wow. It's just relaxed.
It's like yoga for sharks.
Indeed. And there's nothing to
suggest that it's stressed.
I'm barely holding it.
I'm going to hand him to do you, OK?
Just put your thumbs
behind there and hold...
OK, ready? These things obviously
can bite. What would be the damage?
A laceration, at this age.
You might need stitches, actually,
from this little shark.
So, if anything goes wrong,
just let it go.
Let's do our experiment.
Eric's experimental kit
is really simple.
Steel spoon and a magnet. Thanks.
I've been left holding the shark!
I'm not sure whether that's an
enviable position to be in or not.
We have a strong magnet here we're
going to use for the experiment,
and it's a pretty powerful magnet.
It'll attract the spoon
out of my hand.
Eric wants to show me how
our shark reacts to the magnet.
So what we're going to do is put
a blinder by the shark's eye
so he can't see what I'm doing.
So the shark won't be able
see the magnet coming.
OK, I'm going to put a blinder here.
But will he sense it?
I'm approaching...
That was a reaction!
Wow, he jumped out of your hands.
He did.
Our little shark is
completely unharmed,
but he's acutely sensitive
to Eric's magnet.
Why?
Well, it's down to a
clever 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 jelly-filled
tubes that can detect
the voltage difference between
the tube's opening and its base.
They are exquisitely sensitive,
able to pick up
billionths of a volt.
Biologically, we humans
have no mechanism like this.
To us, the ability is
completely alien.
But why would a shark need
such a sense?
It helps them to find food.
It's predation.
They can locate the heartbeat of a
crab or stingray underneath the sand.
When that animal is
beating or moving,
the muscles generate a very
weak electromagnetic field,
and that's what their noses
are gearing in on.
We're, in a sense, simulating that.
The movement of the magnet
across the shark's nose
induces that electromagnetic current,
but we're just doing it many times
greater than a stingray or a crab.
So, it's sensory overload. Exactly.
Hence the struggle. Exactly.
At low levels, this sense allows
sharks to find their prey.
But at high levels, it repels them,
just as we need light to see,
yet would recoil from
dazzling headlights.
But is this effect powerful enough
to change a shark's behaviour?
We're heading from Bimini to
Triangle Rock -
a well-known gathering place
for large Caribbean reef sharks.
We've been joined by
marine biologist Pat Rice.
We're going to pit
a shark's magnetic sense
against what must surely be their
most powerful instinct -
their urge to eat.
Here they are. Look!
Caribbean reef sharks.
Slap it on the water.
Beautiful sharks, aren't they?
They're stunning.
Absolutely stunning, aren't they?
So, they're here. Let's get going.
Stunning they may be,
but to do the experiment,
I'm going to have to jump
in with that lot.
I know they're only two metres,
but they look a little bit bigger
than I imagine a two metre shark.
Maybe it's the water.
Maybe it's acting as a lens
and exaggerating their length.
Pat now needs to set up
the experiment
eight metres down on the sea bed.
What we're going to do here
is perform a very simple,
but hopefully effective, experiment.
And what I've got in my hand here
is an extremely powerful magnet.
That's why I'm not coming too close
to the camera or you will never
see this, it'll wipe
everything in there.
And we're going to make a circle
of these magnets on the bottom,
and in the centre of that circle,
we're going to place some food.
On the sea floor, Pat and safety
diver Vincent are setting up
the circle of magnets,
into which we'll put our bait.
We need to be sure
the sharks aren't simply
deterred by a circle of
black objects, so Pat's made
a second circle of ordinary
bricks covered in black tape.
We'll put bait in the two circles
and see what happens.
The magnets are powerful,
but will they repel the sharks?
Essentially, what we're trying to
test here is whether the sharks'
sensitivity to these magnets will
overcome their desire to feed.
Time for me to join Pat -
and a whole load of sharks.
Jump!
I'm told the sharks in this spot
have never yet attacked a human.
But to do this experiment,
we need to deliberately
tempt them in very close.
We've arrived on the bottom.
On this side is the ring of bricks -
the placebo, if you like.
And here on this side
is the ring of magnets.
And now what we've got to do
is introduce the bait.
OK, we've got sharks here already.
They're coming in.
Pat's got some bait here,
some tasty tuna.
We're going to try and fix this in
the centre of each of the circles.
We're in the water with
hungry sharks,
and in our bare hands,
we've got some fish.
This is like a peculiar game of
Russian roulette, isn't it?
All of those sharks up by the
boat will now be able to smell
the bait down here with us.
Here comes a shark now.
It's bypassed the magnets...
and it's gone
straight into the brick circle
and it's taken the bait.
Now there's no bait in the bricks,
will they show an interest
in the bait in the magnet circle?
Look at that! It turned as
if it could sense that bait,
and it turned away.
It can tell there's food there.
It must be able to see all
of the other fish currently
feasting on it but it wouldn't
go inside that ring of magnets.
Time to put fresh
bait in the bricks.
And I've barely had
a chance to retreat
when a shark makes
straight for the brick circle again.
Look at that.
It's a monstrous great animal.
But so far they haven't touched
the bait in the magnets.
It's 2-0.
It tweaked them
and definitely flinched away.
And yet, they're clearly hungry.
Not me. No, not me...
We're down to our last piece
of bait for the brick circle...
and it doesn't last long.
It's snaffled the
food from the brick circle.
But there's no doubt the magnets
are repelling the sharks.
It seems almost confused
by those magnets.
And the bait remains in the circle.
Although undetectable by us,
in the sharks' mind, our magnetic
force-field is overwhelming.
So strong, it even overrides
the shark's primal urge to feed.
This exploration of animal senses
has been a first
and a fascinating insight
into the animal mind,
and I've been surprised.
The way that they experience
and understand their world
is far more sophisticated
than I would have imagined.
But above all,
I've learned that it's the animal
senses that shape the animal mind.
It's those senses that
make every single species,
including our own,
unique and special.
Next, we'll be meeting the
animals with the most powerful
problem-solving minds on the planet.
How on earth did that crow do that?
We'll find out how apparently
simple animals can crack problems
that would baffle humans...
..and pit them against other animals
I'd like to think of as clever.
All you've got to do
is lift the ball!