Original subtitles

Life in the wild is tough.

Animals sometimes have to pull out

all the stops to survive.

And while some play by the rules, others, it seems,

are more than happy to break them.

The natural world is full of animals who are up to no good.

They're stealing.

Vandalizing.

Fighting.

And even kidnapping.

But is this really as appalling as it looks?

I'm travelling the planet to witness some

of these animal antics firsthand.

They are very cheeky, very cheeky.

Meeting the experts making groundbreaking new discoveries.

That's mad.

And finding out for myself if what appears

to be bad behaviour may just be the secret to their success.

I'm really beginning to love these guys.

That's just clever and funny, but we need our camera back.

I want to show you a fascinating, lesser known side to nature,

where animals have found extraordinary ways to gain

an advantage in the fight for survival.

Every day, animals across the world face immense challenges.

Including when our world collides with theirs.

In the land down under.

Local residents are reporting some anti-social antics from a member

of the parrot family.

Sulphur crested cockatoos.

I want to see the trouble they're causing for myself.

Sometime when I came back home, I found the window open a little bit.

Breaking and entering, into your home when you're out.

- They open the window. - No!

That is very clever.

Using the legs for leverage.

Yeah, just lets himself in when you're out.

These criminal exploits aren't the only problem.

Cockatoos across Sydney have been on the rampage.

Destroying property.

Bothering their neighbours.

Loitering.

And even turning to wanton vandalism.

There are also countless reports of cockatoos littering

the streets with rubbish.

The birds here turn up on a particular day each week. Bin day.

So I can find out exactly what's going on.

I've set up a little experiment.

The red bins in this area are used for food and general waste,

and the yellow bins are for recycling.

What do the cockatoos make of the two bins

I've just put out?

They're certainly inquisitive.

That was pretty incredible to watch, I mean, the first cockatoo

was on the yellow bin for all of five seconds, hopped onto the red

one, flipped open the lid.

He had definitely done that before.

These guys know what they're doing, and they seem to know that the red

bin is the one that has all the food.

These birds are not just intent on causing a mess.

There is a very good reason behind this littering.

They're deliberately rifling through the bin that gets them

a free meal.

But how have they worked this out?

Scientist John Martin has been observing cockatoos for six

years, fitting them with wing tags to monitor their movements.

John, you've done this experiment before.

What do the cockatoos do?

How do they work this out?

So we've seen that an individual has opened one of the bin lids.

It's found there's a food reward and then other birds have mimicked

that behaviour and come in and opened the bin and got some food as well.

And so we see in that group that knowledge

or that information is being shared.

So it really demonstrates that they're intelligent.

In fact, parrots are amongst the cleverest birds on the planet.

Some species have even displayed a level of intelligence comparable

to that of a 4-year-old child.

This brainpower, combined with an in-built inquisitive nature,

is what scientists think is behind all this bad behaviour.

To survive in a new environment, animals need to work out

what will benefit them.

And that includes novel food sources.

This explains the littering.

But what about the cockatoos' reputation for vandalism?

No! Oi!

Stop it.

Some birds have developed a habit of attacking wooden balconies.

Oh, he's peeling away huge strips of it at a time.

Mm-hm.

Yeah, no, that's naughty.

They are very cheeky.

Very cheeky.

So what's all this destructive behaviour in aid of?

Why would cockatoos rip up verandas when there doesn't seem

to be anything obvious to gain from it?

In their forest, home, cockatoos regularly chew on trees

and branches.

It helps to keep their beaks sharp,

and it's where they find bugs to eat.

Cockatoos are using these same techniques in our urban world,

investigating man-made objects to find out if they might be useful.

And with a bite four times stronger than ours,

this exploratory behaviour

is causing extensive damage.

While the people of Sydney may view cockatoos as reckless criminals,

the birds are simply combining all of their natural skills

and abilities to make the most of life in a new home.

In the urban environment

they have to find novel food sources, they have to find habitat,

they have to adapt to different situations.

So being able to solve problems.

Being able to share that information within their groups and maybe

in between groups is really fundamental to them surviving

and being successful in this in a different habitat.

For these cockatoos, city life seems to be working out very well,

and even some of the residents are learning to appreciate

their mischievous nature.

Despite the mess that they make, they are so adorable.

I can't resist them. I love them.

Cockatoos are clever, resourceful little birds that have adapted

stunningly well to new environments.

And ultimately, it's this curious, exploratory nature that's led

to their success in urban environments.

Even if at times it results in behaviours we may not

be entirely enamoured with.

Many animals across the world are known to cause mayhem.

But there is always a perfectly good reason for their bad behaviour

in urban environments.

African penguins taking a fancy to beachwear seem to use

it to line their nests.

North American black bears break into backyards.

Standing in the hammock, not a good idea.

Learning new climbing techniques and how to swim

are important life skills, after all.

From an elephant seal dealing with an uninvited visitor

to his territory, to polar bears getting a little too close

while searching for their next meal, there's a survival strategy

behind these mischievous and sometimes

alarming animal behaviours.

But in some places, they can cause more serious, even dangerous

problems for their human neighbours.

Dawn in Howald.

Where residents often wake up to find something strange

has happened to their cars.

One morning I got into my car and drove and then suddenly

the brakes didn't work.

When I opened the hood of the car and I saw

that even the caps were chewed on and I was like,

Are we having mice around here going into my car?

I don't know.

So what's attacking cars in the dead of night?

Slipping silently through the streets.

Is a stone marten.

Stone martens are relatives of otters and weasels.

They normally live in the hills and forests of Central Europe.

But they've discovered that city living can also offer all the food,

shelter and warmth they need.

So the margins are moving in in ever increasing numbers,

and they've developed a new, alarming obsession.

We have stone marten damaged cars two or three a day.

You see scratches everywhere, little scratches.

You see here the tubes.

It has been completely cut off.

And they are afraid of nothing.

These daring vandals

have made headlines across Europe.

They've become prime suspects for electrical fires.

And they've been caught red handed by mechanics.

In fact, stone martens are causing a staggering 63 million euros worth

of damage every year in Germany alone.

Severed electrical cables, sliced tubing, gnawed insulation.

Not only is this a nuisance for drivers all over Europe,

it can be a serious, potentially dangerous problem.

But why are stone martens targeting cars in this way?

Scientists think it may have something to do

with the time of year.

Recent studies show that stone margins are most destructive

in spring and early summer.

Their breeding season.

To secure a mate, a male stone marten needs to establish a territory

with several females within its boundaries.

And to do this, he scent marks objects around his patch.

Including our cars.

For a male stone marten patrolling territory

is a full time job.

If he's going to be the only one to mate

with his females,

he's got to ward off all of his competition, but inevitably

there will be intruders, and that's when the trouble really begins.

A potential rival will move in on another marten by scent marking

in his territory.

This can provoke a furious response from the original resident.

Who will retaliate by scent marking over the offending smell.

And even try to obliterate everything a rival has touched.

This vandalism might all be down to a scent fuelled

battle over territory.

But there's still one big question, why do stone martens

attack our cars in particular?

It turns out the modern world has thrown these animals a real

curveball.

In their forest home,

stone martens scent mark prominent objects like trees and rocks

to define the boundaries of their territory.

Things that don't tend to move.

But of course, cars move, they're driven all over town.

And this is what scientists think may be fuelling the

stone martens' destructive behaviour.

Imagine each coloured patch here represents

a different stone marten's territory.

This car is parked in one and has been scent marked by a marten.

The following evening, it moves to this different territory.

The marten here smells the scent and now thinks as an intruder,

which sends them into a scent marking frenzy as it attempts

to regain rightful ownership of its patch.

City residents may be inadvertently causing the problem themselves.

Driving their cars between neighbourhoods results

in the illusion of intruders, sparking stone marten territory wars

all over town.

But it's not bad news for everyone.

Well, I find them very lovely, but they bring us a lot of work.

And as for the stone martens.

They'll instinctively continue to fiercely protect their home.

Defending territory is so very important that our beloved cars

have inadvertently become the objects of wanton destruction,

but when you think about what's at stake here for the stone marten,

perhaps it can be forgiven, a chewed up lead or two.

As they get to grips with a modern world, animals are finding

astonishing ways to adapt.

But in the fight for survival, many of them also must contend

with another huge threat.

Predators.

Almost every species on the planet has another that wants

to eat it or kill it.

Finding ways to defend yourself has got to be one of the biggest

challenges to overcome if you're going to survive.

And one tiny crustacean in the Red Sea has devised one

of the most unbelievable strategies I've ever come across.

Beneath the waves.

Amongst the coral lives an extraordinary creature.

The boxer crab.

In a world where almost everything is bigger than you,

you need a foolproof plan to stay alive.

This pufferfish fancies his chances of an easy meal.

But our crab has a secret weapon.

The perfect pair of boxing gloves.

A swift left hook is enough to make this fish think twice.

That's because the crab's gloves are, in fact, sea anemones.

These relatives of jellyfish are just a few millimetres in size,

but they contain a powerful cocktail of toxins in their tiny tendrils.

Every time the crab lands a punch, the anemone delivers

a painful sting.

It won't try that again in a hurry.

But to protect itself from all threats, this boxer crab needs

to keep its gloves in perfect working order.

Which is where our tale takes a sinister twist.

Scientists have discovered that these anemones could grow

up to five times their current size if left to their own devices.

So to keep them small enough to hold, the crab starves them

and takes their food for itself.

Gripped tightly in its claws, the anemones are kept hostage.

Resulting in a somewhat shocking but cleverly

inventive defence mechanism.

But the crab isn't completely out of harm's way.

These anemones have only ever been found living

in boxer crab claws.

Which means that another boxer crab without gloves will inevitably

try to steal its precious possessions.

The thief makes off with one of the anemones.

But our crab isn't out for the count just yet.

It still has one anemone and one is all it needs.

It rips the remaining anemone in half.

But it doesn't kill it because incredibly, anemones can survive

being split in two and regrow naturally from this state.

In time, the boxer crab will once again have the perfect pair

of gloves.

In this treacherous underwater world,

the boxer crab has devised an astounding set of strategies

to help it to survive against the odds.

The tiny crab has evolved such an impressive lifestyle,

using another animal as a tool not only to fight off predators

but to trap its food

as well is, I think, just spectacular.

I bet you'll never look at another crab in the same way again.

The boxer crab has found an effective way to ward

off its enemies, but other animals aren't best suited to confrontation.

I've come to the rainforests of Central America to get up close

to a creature I find irresistible.

The three-toed sloth.

Sloth by name, sloth by nature.

With a top speed of around one mile per hour, they're one of the slowest

mammals on the planet.

This lethargic lifestyle has a rather unsavoury side effect.

Rainforests are sticky, humid places, perfect conditions for mould

and fungi to thrive.

Because sloths don't move very quickly,

even algae will grow on a sloth's fur, turning them a delightful shade

of rainforest green.

And what's fascinating is that each hair follicle has deep grooves

and cracks, which actively encourage algae to establish.

But why would they want a grubby coat?

It could be down to a very clever ploy.

These rainforests are full of impressive hunters.

From huge harpy eagles to stealthy jaguars.

The sloth's fetid fur may act as camouflage, helping

it to hide from predators.

But this living green coat of algae needs extra nutrients

to really flourish, and it gets those from a surprising source.

Sloth fur is also renowned for being full of insects.

Ants like this one up here, and dung beetles usually at their rear end,

but most importantly, hundreds of moths.

This species of moth here can only be found in sloth fur,

and they're everywhere on this young lady.

This writhing mass of moths is vital to the sloth's green camouflage.

Because the dead moths and their droppings provide

the nutrients for the algae to grow.

It might seem a little bit off putting to us, but she's adapted

her entire lifestyle to keeping her fur

teeming with the species of moth.

But there's more.

Once a week, three-toed sloths make a slow and perilous journey

down to the forest floor to defecate.

No other tree dwelling animal does this, and it puts them

at great risk of predators.

So why do they do it?

It's all to do with the moths.

When the sloth is on the ground, female moths hop off her fur

and lay their eggs in its faeces.

The larvae then feed here before the emerging moths find

another sloth to live on.

The sloth risks everything to complete the moth's life cycle,

and in turn, the moths provide the fertiliser for the algae

in their fur, which is vital for the sloth's

camouflage and survival.

But that's not all.

Research suggests that this filthy coat could provide her with

the nutrition she so desperately needs.

Sloths are folivores, specialist leaf eaters.

It's a diet that's very low in nutrition, but the sloths

have an ingenious solution.

They feed on the algae that's growing on their fur.

With five times more fat than tree leaves and an array of important

nutrients, it gives the sloths a much needed boost to their diet.

She may be slow and have what seems to be highly questionable hygiene

standards, but the three-toed sloth has evolved an exceptionally clever

and novel camouflage, as well as a source of nutrition.

So for this species, at least, lethargy and unkempt fur

are a recipe for success.

They might seem distasteful to us, but for some animals,

repulsive habits can be very useful for survival.

Elephants actively recycle their own dung.

This behaviour called coprophagia provides them with vital bacteria

that helps them to digest their food.

Fulmar chicks ward off predators with oily projectile vomit,

it sticks to the feathers of their attackers and stops them

from flying.

And life underwater is no less repellent.

Pygmy sperm whales perform what's known as defensive defecation.

A cloud of faeces conceals them from predators, allowing them to make

a swift exit.

As unsavoury as all of this appears, it might just encourage you to steer

well clear and avoid any unwanted attention.

The need to fend off predators has driven the evolution of a whole

host of extraordinary and sometimes stomach turning tactics.

But even some of the world's most fearsome hunters must find ways

to avoid becoming prey themselves.

This is the home of a predator with an astonishing skill set.

The puff adder.

With an attack speed of just a quarter of a second,

lethal tissue destroying venom,

superb camouflage for concealment,

and an outstanding sense of smell to track prey.

This is the ultimate hunter.

But perhaps surprisingly, it's not invincible.

This formidable reptile has over 40 different predators of its own.

Including the feisty mongoose and the vicious honey badger.

To succeed as a predator, the puff adder must avoid being eaten.

And to do that, it has a very devious trick.

A team from Wits University recently made an extraordinary discovery

with their camera traps.

This genet walks straight past a puff adder.

And this porcupine treads right on it.

These animals use their sense of smell to find food

and locate danger.

So even in the dark, they should be able to sniff out the snake.

So does the puff adder have another weapon in its arsenal, which allows

it to deceive prey and go undetected?

To find out, the research team have set up an innovative experiment.

They've enlisted the help of the meerkat.

With their exceptional sense of smell, meerkats detect and chase

off intruding snakes from their territory.

But venomous snakes will also make up part of their diet.

Scent samples are carefully collected from different snakes.

And placed in tubes.

One tube contains a control scent, the smell

of a sterilized, empty tank.

The meerkats will be given a food reward if they manage to recognise

a specific scent.

Right now, I'm showing the meerkats what she's looking for.

In this tube

is the scent sample of a brown house snake.

To the meerkat, it will have a very distinctive smell.

Now, to find the matching odour in the row of tubes.

There, she's got it. Brown house snake.

It now needs to find the matching tube for the puff adder scent.

But this time it doesn't seem so easy.

So now she's indicating the control, which means you can smell the tank,

the empty tank, which essentially smells of nothing,

and she carries on searching.

She can still smell something on that.

She's also indicating puff adder, which means

she can't tell them apart.

Since it chooses both scent tubes, the meerkat simply can't distinguish

between the smell of the snake and the empty tank.

It's as if the puff adder has no scent at all.

So this is a form of chemical cryptic.

Camouflaging themselves.

This is a fascinating discovery.

The puff adder has evolved a means of masking its own scent.

So it can hunt while still evading predators.

It's the first land vertebrate known to use this disguise

for its own defence.

But exactly how it does it remains a mystery.

The puff adder has mastered the art of survival.

From fatal venom to ingenious deception.

This is a truly remarkable reptile.

The ability to hide in plain sight is an incredibly skilful way

to avoid predators.

But other animals can take a more ruthless approach.

They'll even turn on their own kind to stay alive.

On British beaches,

hidden in rock pools

live tiny animals facing huge challenges.

Hermit crabs.

Hermit crabs don't have a complete outer skeleton like most other

crustaceans do, they have a soft exposed abdomen that leaves them

vulnerable to predators, so they've got to find a suitable

shell to protect themselves.

As hermit crabs grow, they need to upsize their home.

But sometimes a suitable new shell isn't that easy to come by.

When you're only as big as a 10p piece, a vast beach like this one

is a challenging environment in which to find the perfect shell

and one that isn't already occupied.

So the hermit crab has devised a dishonourable tactic to make sure

it gets what it needs.

Another hermit crab with exactly the right shell for our growing crab.

There's only one thing for it.

Brute force.

An all out fight isn't enough.

It needs a new tactic.

Using its own shell as a weapon,

it attacks the current owner.

The faster it wraps, the more it's proving its strength and stamina.

It's deliberate intimidation.

Cowering inside, the victim tries to hold on.

It won't give up its home that easily.

But our attacker has a final, devastating move.

It's a forceful eviction.

Leaving the loser homeless.

And the victor with the ideal new shell.

This may be blatant theft, but the hermit crab's

aggressive strategy pays off.

It's found an ingenious way to ensure its survival.

Animals will use every imaginable tactic to outwit enemies and stay

alive, from theft and hostage taking to sophisticated deception.

But what if the threat came from closer to home,

from your own relatives?

Just off the coast of South America, one bird of prey reigns supreme.

The striated caracara.

It's one of the rarest raptors in the world.

In spring, it feasts on the eggs and chicks of the island's

vast seabird colonies.

For caracaras, these are prime feeding grounds.

Each adult has carved out its own territory in which to hunt.

And there's no space left for anyone else.

This juvenile needs food.

Still too young to have its own territory,

there's little access to the hunting grounds.

Another youngster decides to chance its luck.

But the adults are all too willing to take down any trespassers.

The risk of injury in these brutal confrontations is too high.

Getting to the food requires a new plan.

Up on the moorlands, the young caracara isn't the only

one in exile.

New research has found that juvenile caracaras use distinctive calls

to rally together.

This gang of youngsters are planning a rebellion.

Working together as a group, they invade

an adult's feeding territory.

The balance of power shifts.

The adults can't see off the entire flock.

Their mobbing technique has paid off.

Gorged with food, the young birds return to the moorlands.

Being forced to live on the periphery is tough

and rising up against the adults is the only way to survive.

For young caracaras, turning on the adults of your species

is a necessity.

But other species can benefit from working together

throughout their lives.

Ethiopian wolves share in the caring of their young.

African elephants pass vital knowledge about food

and water sources down the generations.

Penguins huddle together for warmth to survive.

And killer whales are incredibly successful hunters as a group.

But it's not always happy families.

To maintain order,

there's often a strict hierarchy, with one animal leading the group

and the rest falling into line behind it.

When it comes to survival, there are real benefits to living

in a group, and if you're the dominant animal at the top

of the pecking order, you're going to get the vast majority

of the perks.

But to get there and to hold on to that power once in charge takes

clever, cunning and sometimes even pretty shocking tactics.

Deep in the African jungle.

Chimpanzees live together in large social groups.

Their day to day lives are relatively harmonious.

Until the peace is broken.

By the alpha male.

He will scream, display and charge to maintain his status.

Tanzania's Gombe National Park.

I'm meeting chimpanzee expert Michael Wilson.

I want to find out why using aggression can be so important

for these apes.

It's early in the morning.

We've been tracking for about an hour or so.

And just off the track, this magnificent scene.

I've never seen chimpanzees in the wild,

so it's all a little bit mind blowing.

And this really is quite a peaceful, serene scene.

This is the Kasekela community.

The chimpanzees here have been studied for nearly 60 years,

resulting in a unique opportunity to better understand the dynamics

between these animals.

Down below in the valley

we can hear all sorts of calls where all the males are.

I presume that's where it's all kicking off.

Michael and I trek further into the forest to find the rest

of the group.

That's the alpha male right there.

And who's with him?

His mother is right next to him.

It's all going off in this family group this morning.

Classically, we tend to think of the alpha males as the strongest

elder powerful males who take care of the whole group.

Is that the case in chimpanzee society?

It doesn't really seem to be.

The alpha male really seems to be in it for himself.

It's about benefiting the genes that he has inside of him

and about making as many copies of those genes as he can.

The latest research is revealing that dominant males are employing

self-serving strategies rather than those that might benefit

the entire group.

Essentially, male chimps are focused on having as many

offspring as possible.

And intimidation ensures everyone knows who's boss.

But it's not always easy at the top of the pecking order.

How precarious is his position?

How often does he have to fight off potential usurpers

to the throne?

Pretty much every day there's the other males are always

jockeying for position.

They're always looking for a chance to rise in ranks.

They're always looking for weakness.

Most alphas use a combination of political manoeuvring

and aggression to gain and maintain power.

But over the years, researchers have reported some males with a level

of brutality that seems unusually high, even for chimps.

So can individuals have distinct and even sinister personalities?

One alpha, well known to the scientists,

reigned here back in 1997.

His name was Frodo.

Footage captured during that time shows how he maintained his position

through a terrifying combination of intimidation and violence.

We were all afraid of him because he would go after people

as well as chimps.

Frodo was a ferocious fighter during attacks on other chimpanzee

groups, but that aggression spilled over to anyone in his way.

And did you ever have any firsthand experience with Frodo?

When I first got here, he followed me and knocked me into the bushes

and hit me with his fists for a little while.

Every time I saw him, I would feel a little bit of fear.

That's what life is like for all of the other chimps

because you're always on the lookout.

Frodo's behaviour was certainly extreme.

His attacks often appeared malicious and unprovoked.

At times, he seemed to behave badly simply because he could.

People really talked about him as if he were a bully.

Normally with chimpanzees, there's a lot of reciprocity.

You scratch my back. I'll scratch yours.

With Frodo it's you scratch my back.

- That's it. - That's it.

Frodo held the alpha position for five years before becoming ill.

With eight offspring,

he was the second most successful male in Gombe history,

and he was by far the most brutal.

If humans acted similarly, some scientists might consider them

to be psychopaths.

Roughly 1% of people show psychopathic traits characterized

by lack of morals and empathy, fearlessness, ruthlessness

and volatile aggression.

New research is revealing that like us, individual chimpanzees

have distinct personalities.

So could some be more inherently violent than others?

And what kind of conclusions have you made about their individual

characters and why they behave so badly?

You know, part of being a male chimpanzee involves a certain amount

of being able to dominate others and chase them around.

It really does seem to be part of their inherent strategy.

The bullies are the ones who make it to the top.

For an alpha male chimpanzee, being a bully can lead to success.

But there will always be some individuals like Frodo

that are exceptionally aggressive.

They're doing whatever they need to do to get the greatest reward.

Fathering as much of the next generation as possible.

This is such a fascinating example of how individual animals

within the same species can have very different personalities.

Now it's probably fortunate for the group that the more extreme

alpha males are seen to occur relatively rarely.

But for those dominant males, being so badly behaved seems

to be a very successful strategy for survival.

On my journey throughout this beautifully

complex animal kingdom,

I've seen animals fight...

..deceive, cheat

and steal their way to success.

Look at this.

Whether it be to breed.

Think he's getting a bit frisky.

Shaking his tail feathers.

To find food.

Or just to survive.

The latest science is revealing exactly

what animals will do to overcome life's greatest challenges.

What we might perceive as bad behaviours are, in fact, evidence

that all sorts of species, from the smallest crustaceans

to our closest ape relatives have evolved sophisticated

and ingenious strategies that are not so different to our own.

For me, that brings about a huge sense of respect and admiration

for the animals we live alongside.