Original subtitles

The world is full of extraordinary animals.

But how well do we really understand them?

How do they really think and feel?

To find out, a team of spy creatures is going undercover.

They not only look like part of the family,

they behave like them, too.

Armed with the latest camera technology...

..they are going to travel the globe...

..to understand the true nature of the animals they meet

and reveal how intelligent they really are...

..how badly behaved they can be...

...how important friendship is to them...

..and if it's possible

that they can truly love each other.

What they discover will change our perception of animals forever.

Perhaps they are more like us than we ever believed possible.

SCREECHING

Animals live complex lives,

but how sophisticated are their emotions?

On the African savanna lives one of the world's most intelligent

and family-focused animals -

the wild dog.

In this pack, all the puppies belong to just one mother,

but are showered with affection

by every member of the extended family.

When the adults go hunting, a new pup makes an appearance.

This is spy pup. The only giveaway

is the camera in his eye.

YELPING

He is here to film the emotional dynamics of pack life,

but first, he must be accepted by the pups.

They could easily rip him to pieces...

..so he mimics their body language, to make them feel at ease.

He uses the play bow.

It's a universal invitation to have fun.

He's won them over,

despite his slightly-strange smell.

The adults, however, may be harder to convince.

So, he makes a submissive gesture and wags his tail.

GROWLING

Now accepted, he soon gains the most intimate view

of wild dogs ever seen.

The pups beg for food by licking the adults' mouths.

Fresh meat caught just for them.

With survival depending on teamwork,

affection strengthens family ties.

Unfortunately, it's not just spy pup that's watching them.

BARKING

The strength of their love is about to be tested.

Lions regard wild dogs as rivals.

She'll kill the pups, if she can.

Spy pup can only lay low and observe.

The lioness picks up the smell of the den.

The dogs try to divert her attention.

WHINNYING

But with pups in her sight, she won't be easily distracted.

The pack keeps up the diversion.

But it's the desperate mother who decides to risk all...

..goading the lioness to attack her.

Over and over, she teases the lion,

while the pack provides backup.

After 40 minutes of relentless pressure,

the exhausted lioness accepts defeat.

Spy pup had a ringside view of this extraordinary encounter.

And in the aftermath, the pups are reunited with their mother.

Although family affection runs deep,

nothing competes with the love of a mother.

After the lion's visit, it's her that cleans the den.

For her pups, it's a chance to enjoy the dust bath.

Even spy pup joins the fun.

A mother's love is so fundamental,

could it be found in a relic from a prehistoric age?

In Uganda, this Nile crocodile

is coming ashore for a very important event.

Her babies are about to hatch.

Sharing her nest are some very special hatchlings.

Ones with cameras in their eyes. They are here to record

the relationship between a mother crocodile and her young.

The spy hatchlings have been filming her for days,

as she waits for her real young to arrive.

CAWING

The calls of her babies synchronise their hatching,

encouraging the whole brood to emerge at once.

They are also cries for her attention.

For three long months,

she protected her eggs day and night,

as she waited for this moment.

Now, she meets her babies for the first time.

They are delicate and vulnerable.

GROWLING

But they are not safe here. She must get them to water.

Her solution is extraordinary.

Despite having the most powerful bite in nature,

she carefully gathers them in a throat pouch,

beneath a stockade of deadly teeth.

She is as gentle as a croc could ever be.

Safe in her care, tails dangling between her teeth,

she takes them to water.

She won't enjoy her babies' company for long.

Crocodiles can have 80 hatchlings...

..and another batch is crying for her attention.

CAWING

She won't leave any behind.

Even spy hatchling.

Safe in her cavernous mouth, all survive unscathed.

And spy hatchling is still filming.

They still need her protection.

Even in the water, just one in ten survive...

..for danger is everywhere.

A grey heron.

He has the pick of the bunch.

Crocodiles have changed little since the age of the dinosaurs,

but their maternal care is anything but primitive.

She'll protect her babies for the next two months.

Such care becomes stronger when whole families are involved.

African elephants show a much more developed sense of love.

Their extended family is made up of related females,

led by a wise old matriarch.

She holds the wisdom of the generations

and this needs to be passed on to all.

To infiltrate the herd, a new spy creature is needed.

One based on a bird that lives among them.

This is spy egret, complete with a filming eye.

The first challenge will be surviving the initial encounter.

It could be a brief assignment.

CAWING

He is facing 40 tonnes of unstoppable herd.

His first test over,

it's now down to business.

As well as spy egret, there are other cameras covering the action.

Spy tortoise can, quite literally, get under the elephants' feet.

The cameras soon capture something remarkable.

A vulnerable new arrival, less than an hour old.

His mother must help her new-born to his feet.

It's the start of the most important relationship of his life.

His first steps are a challenge.

The bond between them will be complete when he finally suckles.

Easier said than done.

His mother gently guides him to the spot.

It's time to meet the relatives.

It's a big occasion.

Each member of the family wants to introduce themselves.

They will all play a role helping him grow up.

For now, the attention is overwhelming.

But in the coming years, he'll learn all he needs to know

for his survival from these loving females.

The babies of some animals have to find their place

in even larger animal families.

This temple in Rajasthan

is home to a troop of 120 Indian languors,

made up of related females and their offspring.

They are the most gentle and affectionate monkeys in the world.

It's a sisterhood with an unusual system of childcare.

To see how this works in practice,

a spy baby monkey is joining the family -

complete with camera eye and a range of life-like movements.

The plan is to blend subtly into the crowd.

But the monkeys have other ideas.

They are more than a little suspicious

of the stranger in their midst.

She's creating such a stir,

every monkey in the neighbourhood pays her a visit.

Her camera reveals the extraordinary athletic prowess

of these lively monkeys.

To escape the pandemonium,

the mother has set up a baby and toddler group

in a quiet part of the temple.

But looking after baby is a full-time occupation.

So, once they are three weeks old, if Mum wants a break,

she has a solution - employ a teenage baby-sitter.

As these young females develop feelings of love and care,

they just want to hold a baby.

It's an arrangement that gives the mums a break.

A chance to be pampered and groomed.

She may have a designated baby-sitter, but here,

every young female wants to play mum.

When everyone's had a go,

there's always one left holding the baby.

It's a serious responsibility,

but the novelty soon wears thin,

especially when everyone else is having all the fun.

The baby-sitter decides to join the game...

..while the baby clings on for dear life.

But some challenges test the baby's grip to the limit.

An almost sheer drop of 20 metres.

The babysitter is oblivious to the danger.

For the baby, a final indignity.

SQUEALING

Time for the mother to reclaim her infant.

The babysitter wants a break, too.

There are plenty more volunteers, but for both baby and mother,

enough is enough.

It seems traumatic,

but this is how teenagers learn the parenting skills

they'll need in the future.

There's no shortage of love here,

even if, at times, it's tough love.

The prairies of North America,

home to an animal with a surprisingly-loving nature.

This inquisitive soul is the prairie dog.

He has a new neighbour.

Spy prairie dog.

CHIRPING

Everyone's curious to see the new arrival.

They live in towns, made up of around 20 family groups.

In these wide open spaces, everyone relies on each other

to watch for danger.

So, to strengthen their family connections,

they have an endearing way to express their affection.

Kissing.

Like a human kiss,

it's thought to encourage the bond of love and release oxytocin -

a pleasure hormone that floods the brain.

It also helps identify family members

and strangers from out of town.

But when a rival male blatantly steals a kiss,

it doesn't go down well with the head of the family.

The cheating female wisely hides, as fur flies.

Love rival gone,

the prairie dogs regroup,

with an enthusiastic display called a jump-yip.

The jump-yip shows the colony is alert and on guard.

It also reinforces its unity,

ensuring everyone is on the same wavelength.

Even spy prairie dog gives it a go.

CHIRPING

CHIRPING

BELLOWING

Back on the African savanna,

the new-born elephant is on the move

and he now needs the protection of his family more than ever.

The spy creatures are on duty, too.

As they travel, the mother uses her tail to make sure her baby

is always in touching distance...

..for danger can come from the most unexpected places.

And wild dogs can be a threat,

especially when they have their own pups to protect.

For now, they are blissfully unaware that the elephants are close.

The pups are constantly playing,

building the social skills they need to be fully part of the pack.

ELEPHANT BELLOWING

But the elephants are getting closer.

They could easily destroy the den and crush the pups.

The dogs advance, to meet the threat.

Wild dogs are effective killers,

able to take down a new-born elephant.

But their only concern now is the safety of their own young.

Stragglers are rounded up.

The elephants are equally concerned for their own baby.

They shepherd him behind a protective wall of legs.

The dogs create their own barrier between the elephants and the den.

It's a showdown.

The matriarch leads the charge.

BELLOWING

She's the most experienced member of the family.

As the conflict escalates,

the elephants put on a united show of strength...

..with the baby hidden behind a moving barrier of legs.

Eventually, the two sides accept an uneasy truce.

Both loyal and loving families know there's too much to lose

from further confrontation.

With spy tortoise now fully accepted by the herd...

..the elephants bring him along for the ride.

Albeit, a brief one.

The affection that binds families together may be strong,

but the bond between courting couples is in different realm.

In southern Kenya, love is blossoming.

This male red-billed hornbill

has found the perfect spot to bring up a family.

His mate is never far away.

He performs a little dance,

to entice her to take a closer look.

She shows her approval by starting to spruce the place up.

They now face a challenge that will test their commitment to the limit.

They set to work, gathering mud -

a central element to their plan.

Their aim is to make the entrance smaller.

They also add poisonous millipedes to the mix,

creating an insect repellent that keeps nest-raiding pests at bay.

The hole is shrinking fast, so before it gets too small,

the female must move in.

This tiny chamber will become her home for the next 12 weeks.

She's a willing captive,

even using her own droppings to help narrow the hole.

She now relies on her mate to deliver more building materials.

Working as a team, the female narrows the entrance from within.

Their plan is to make a prison cell,

but one purely for her protection, as it keeps predators, like snakes,

from entering.

Soon, the hole is reduced to a mere slit,

just big enough to squeeze in supplies.

Eventually, the eggs are laid.

Among her clutch is a special spy egg,

one that will record the next stage in this incredible story.

As the weeks go by,

her mate's only concern is to keep his partner well fed.

She is completely dependent on him.

He brings her up to 20 large insects each day, while she incubates.

But what goes in, must come out.

Nest hygiene is essential.

25 days after laying, the moment has arrived.

CHIRPING

She has a brood of three,

plus one adopted chick(!)

Spy egg has become spy hatchling.

One chick takes him under her wing.

With more mouths to feed, the male is in overdrive,

finding at least 70 insects each day.

They have voracious appetites...

..but at least one beak doesn't need feeding.

The mother divvies up the food between her growing brood

as best she can.

But after being cooped up for over two months,

the lack of space and constant quarrelling

is getting too much for her.

She starts to chisel her way out...

..testing the hole for size.

To keep her babies safe, it must stay predator-proof.

It seems an impossible squeeze, so easy to get stuck.

Freedom.

The chicks instinctively use spittle and droppings

to close up the entrance again.

Now, the hard work can be shared.

Each chick needs one insect every ten minutes.

One bird alone couldn't keep up with demand.

Spy chick even gets a mouthful.

But, of course, he shares it around.

The parents will feed their chicks for another three weeks,

until they are ready to fledge.

Few birds show such dedication. It's the ultimate expression of trust.

They'll remain faithful for their entire lives.

Not all partners show the same devotion.

The cold wastes of Antarctica.

For Adelie penguins,

the challenges start the moment they arrive from the ocean, to breed.

The males race to their nesting grounds,

desperate for a head start on their rivals.

As soon as they arrive,

the quarrels begin over who gets the best nest sites.

Spy Adelie enters the fray.

But to film their complicated love life,

it's vital he fits in.

His courtship display makes him one of the gang,

as they wait for their mates to arrive.

The females are fussy partners and the males fight over pebbles,

to make sure they build them the biggest and finest nests.

And they don't mind who gets in their way.

A late arrival hurries into the colony.

With the best nest sites taken, he is forced to the outskirts,

where no-one wants to be.

It's a cold and soggy place to build a love nest,

especially when the point of the pebbles is to keep their eggs

raised and dry.

Spy Adelie helps as best he can...

..with a well-placed pebble cam.

But the latecomer isn't discouraged

and gathers more pebbles, as fast as he can.

But round here, you can't turn your back for a second.

As soon as he puts it down, his pebble is stolen.

The thief embellishes his impressive nest.

Oblivious, the latecomer is travelling ever further

to find stones...

..while the crook takes advantage of the moment.

He may have no moral code, but he certainly has a magnificent nest.

In contrast, the latecomer's nest remains in a sorry state

and the criminal penguin is getting ever more brazen...

SQUAWKING

..taking another trophy back to his ever-growing pile,

..while the latecomer is becoming despondent.

To make matters worse,

the females have started to arrive.

Females often remain faithful to their partners,

but only if the nests meet their high expectations.

So, for the latecomer, the pressure is on.

She makes a considered inspection.

Perhaps one last stone will swing it?

He awaits her verdict.

Her reaction is somewhat disappointing.

Nearby, the bachelor thief proudly shows off his ill-gotten gains.

There is only so much a female penguin can resist.

She wants a male with a dry, raised nest,

where her eggs will survive.

And she's found one.

But her jilted partner won't give up without a fight.

It was a brave effort,

but it wasn't enough.

She chooses the thieving male with the finest nest.

Her mate makes one last plea...

..but it's all in vain...

..and he's subjected to the final indignity.

But Adelies are plucky and irrepressible birds

and, if you can't beat them, join them.

You can always build another nest,

especially with a little help from a friend.

Back in the warmth of Africa,

spy tortoise is going undercover in more familiar territory.

He's spending time with real tortoises,

to record what insights into love they might offer.

This leopard tortoise is desperately seeking a romantic liaison.

As he sets off on this amorous quest,

spy tortoise plays gooseberry.

The hopeful suitor's technique lacks a certain subtlety.

First, he gives chase.

And then, a bit of a barge.

CLUNKING

If you're covered by a hard shell, it's difficult to be sensitive.

And there's nothing subtle about what happens next.

GASPING

Spy tortoise is here to observe,

but things don't always go to plan.

Probably best to forget that ever happened.

For our spy creatures,

being immersed in the world of animals is not without its hazards.

In Rajasthan,

the temple languors have taken spy monkey into the heart of the family.

But some are keen to take the budding relationship

to the next level

and are getting a little too familiar.

One seems to want to babysit her.

But disaster strikes.

An injured baby is a cause for concern.

And this languor seems to believe she's died.

Then, something extraordinary happens.

The monkeys gather round the motionless spy creature,

as if it is a real baby.

They react just as they do when their own babies die.

A calm and contemplative mood descends on the colony.

There's a sense of grief, as well as empathy for one another.

Quite accidentally, our spy creature

is at the centre of something extraordinary, capturing emotions

that have rarely been observed.

Such apparent expressions of grief may not be unique to primates.

On the African savanna,

spy tortoise is party to another unique event.

Giraffes are appearing from every direction.

This is what they've come to see.

An old giraffe has passed away

and it seems to have profoundly affected those

who share these vast grasslands.

And more keep arriving,

creating an unprecedented assembly, never witnessed before.

The giraffes kept arriving throughout the day,

seemingly paying respects to the old male.

An awareness of death

was previously believed to have involved just a few

highly intelligent species, but this seems to suggest otherwise.

Such deep feelings are to be more expected among chimpanzees,

but these intelligent animals still have the capacity to surprise.

In the forests of Senegal,

spy bushbaby is part of a team of spy cameras

capturing intimate views of our closest living relatives.

Here, the family lives a charmed existence.

Parental love and friendships form the foundation of their society.

Spy tortoise is also being deployed.

But these are highly-perceptive animals...

..and something's not quite right.

This five-year-old checks what the others are thinking.

They seem equally baffled.

But with his curiosity piqued, he simply can't stay away.

As his interest grows, so does the strength of his feelings.

SCREECHING

He just has to have spy tortoise all to himself.

He hides with it in his leafy daybed,

where he'd normally take a nap.

But he's too excited to sleep.

He's torn between using it as a pillow and giving it cuddle.

It's somewhere between a toy and a pet.

SCREECHING

It's definitely not for sharing.

Chimps don't normally have possessions,

but spy tortoise has stirred new emotions.

Elsewhere in the forest,

spy bushbaby is helping document an equally-unique event.

One of the older chimps is playing with a tiny kitten.

It's the offspring of a genet cat found abandoned in the forest.

He treats it with kid gloves, mindful not to hurt it.

Even a nip is tolerated.

The way he responds to the genet

shows a very rare emotion in animals - empathy.

Other chimps are intrigued.

And one shows an unwelcome interest.

This older chimp is used to having his own way,

but without any feelings for the kitten, he's a bit too rough.

The owner shows real concern and intervenes,

to protect his vulnerable pet.

And takes it from harm's way.

They hide behind a termite mound.

It's not just a private spot, it's also a chance for a snack.

By using a stick, he can fish for termites.

It's an intimate moment enjoyed with a special companion.

Perhaps this is how human pet-keeping began.

This is a glimpse of something quite remarkable -

the first stirrings of empathy for another species.

In the animal world,

there are more ways of showing love and affection

than we ever thought possible.

From maternal devotion,

to family affection.

Through jealousy...

..grief...

..and romantic liaisons.

These many incarnations of love in the animal world may offer

a mirror to our own complex feelings.

Next time, a team of new spy creatures

film how intelligent animals really are,

with some extraordinary revelations.