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S36 Ep14

Natural Born Rebels | Episode 2 | Survival

Premiere: 5/2/2018 | 00:00:35 | Closed Captioning Icon

Some animals will do whatever it takes to survive. Cockatoos turn to vandalism, boxer crabs hold anemones hostage, sloths become filthy, puff adders have an ‘invisibility cloak’ to hide themselves, and chimps use violence to stay in power.

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About the Episode

Some animals will do whatever it takes to survive. Cockatoos turn to vandalism, boxer crabs hold anemones hostage, sloths become filthy, puff adders have an ‘invisibility cloak’ to hide themselves, and chimps use violence to stay in power.

Noteworthy Facts:

  • Sulphur-crested cockatoos are notorious for vandalizing and littering Sydney, Australia on garbage day. These inquisitive and clever birds have figured out which colored bins they can find scraps of food in, and this adaptation to the urban environment has made them curious to try to discover other food sources around the city, even if it means damaging property.
  • Stone martens have found a new haven in the cities of central Europe and are causing extensive damage to cars; there’s been an estimated $75 million worth of damage per year in Germany alone. Research suggests the destructive behavior is tied to the need to secure a mate through scent-marking of territories. Cars carry the scent marks around the city and confuse the Stone martens into thinking their territory is being encroached upon.

Buzzworthy Moments:

  • Boxer crabs carry glove-like sea anemones full of toxins in order to defend themselves. One courageous boxer crab fights off a pufferfish, throwing a punch with a powerful sting.
  • In the rainforests of Central America, algae grows on a three-toed sloth’s fur, acting as camouflage against predators. The algae needs nutrients to flourish, which it gets from hundreds of moths also stuck in sloth fur. Once a week, the sloth makes a perilous journey down to the forest floor to go to the bathroom and replenish its moth collection.
  • The Striated caracaras, birds of prey, on the Falkland Islands carve out territory to feast on the eggs and chicks of the island’s vast seabird colonies. In order to get past the adults guarding the food, the adolescent falcons form a gang in order to overpower their elders.
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PRODUCTION CREDITS: EPISODE 2

NATURAL BORN REBELS
EPISODE 2: SURVIVAL

NARRATED BY
ALLAN PECK

PRODUCED & DIRECTED BY
JOANNE ASHMAN

PHOTOGRAPHY
STUART DUNN
KEVIN FLAY
PETE HAYNS
STEVE PATON
ALEXANDER VAIL

SOUND
PARKER BROWN
PHILIP MYERS
BILL RUDOLPH
ZUBIN SAROSH
GARY STADDEN

EDITORS
JACOB PARISH
ROSS MCFALL
PAUL KIFF
EMMA JONES

EDIT ASSISTANT
SINEAD COOPER

COLORIST
TONY OSBORNE

ONLINE EDITOR
ALEX MOFFATT

DUBBING MIXER
BRIAN MOSELEY

DUBBING EDITOR
DAVID YAPP

GRAPHICS
KISS MY PIXEL

ORIGINAL MUSIC
WILL HYDE
SIMON PITT

PRODUCTION MANAGER
JANELLE BACKES

PRODUCTION COORDINATORS
LESLEY BISHOP
AMANDA MCFALL

ASSISTANT PRODUCER
EMMA BRENNAND

RESEARCHERS
ESTELLE CHEUK
JOLYON SUTCLIFFE

ARCHIVE RESEARCH
DAVE COX

SPECIAL THANKS
DR LUCY APLIN
YISRAEL SCHNYTZER
YANIV GIMAN
YAIR ACHITUV
ILAN KARPLUS
BRYSON VOIRIN
DR XAVIER GLAUDAS
PROFESSOR GRAHAM ALEXANDER
PROFESSOR MARK BRIFFA
BAR ILAN UNIVERSITY – GOODMAN FACULTY OF LIFE SCIENCES
IKHAYA LAMADUBE GAME LODGE
GOMBE NATIONAL PARK
JANE GOODALL INSTITUTE

ARCHIVE
TOURISM AUSTRALIA
MEDIAWORKS NEWS ARCHIVE
POND5
SHUTTERSTOCK

COMMISSIONING EDITORS
ABIGAIL PRIDDLE
LUCINDA AXELSSON

EXECUTIVE PRODUCER
JO SHINNER

UNIT MANAGER
MARIA NORMAN

SERIES PRODUCER
HOLLY SPEARING

FOR NATURE

SERIES EDITOR
JANET HESS

SENIOR PRODUCER
LAURA METZGER LYNCH

COORDINATING PRODUCER
JAYNE JUN

ASSOCIATE PRODUCER
JAMES BURKE

LEGAL COUNSEL
BLANCHE ROBERTSON

SOCIAL MEDIA EDITOR
WHITNEY MCGOWAN

AUDIENCE ENGAGEMENT
CHELSEY SAATKAMP

BUDGET CONTROLLER
JAYNE LISI

ONLINE EDITOR
STACEY DOUGLASS MOVERLEY

RE-RECORDING MIXER
ED CAMPBELL

ORIGINAL FUNDING PROVIDED IN PART BY
THE ARNHOLD FAMILY IN MEMORY OF CLARISSE ARNHOLD
THE HALMI FAMILY IN MEMORY OF ROBERT HALMI, SR.
SUE AND EDGAR WACHENHEIM III
KATE W. CASSIDY FOUNDATION
LILLIAN GOLDMAN CHARITABLE TRUST
FILOMEN M. D’AGOSTINO FOUNDATION
ROSALIND P. WALTER
SANDRA ATLAS BASS
CORPORATION FOR PUBLIC BROADCASTING

SERIES PRODUCER
BILL MURPHY

EXECUTIVE PRODUCER
FRED KAUFMAN

A CO-PRODUCTION OF THIRTEEN PRODUCTIONS LLC AND BBC STUDIOS IN ASSOCIATION WITH WNET

THIS PROGRAM WAS PRODUCED BY THIRTEEN PRODUCTIONS LLC, WHICH IS SOLELY RESPONSIBLE FOR ITS CONTENT

© 2018 BBC
ALL RIGHTS RESERVED

TRANSCRIPT

♪♪ NARRATOR: All animals face the same challenge.

They must find a way to stay alive.

And in a tough world... that's never easy.

So to get what they want, some animals will break all the rules.

[ Squawks ] Meet the planet's greatest rebels.

[ Squawking ] They'll steal... deceive... and even resort to brute force.

These wild rebels are getting to grips with our urban world in surprising ways.

But could behaving like this actually be the secret to their success?

We'll reveal new discoveries and astonishing science as our rebels strive to outwit their enemies... and get ahead in the fight for survival.

♪♪ ♪♪ ♪♪ ♪♪ NARRATOR: Every day, animals across the world face immense challenges.

Especially when our world collides with theirs.

♪♪ In the land down under lives a member of the parrot family... ...the sulfur-crested cockatoo.

And as they get to grips with the urban world, these birds appear to be going on a rampage across Sydney.

[ Squawks ] Destroying property... annoying the neighbors... ...loitering... and even breaking and entering... [ Feet patter ] [ Squawks ] The residents in this suburb are reporting these rebels are also turning up on a particular day each week.

♪♪ Garbage day.

And they've been covering the streets with trash.

So what are these feathered felons up to?

In this area, the red bin is for food and general waste and yellow is for recycling.

♪♪ ♪♪ ♪♪ They're definitely curious.

♪♪ ♪♪ It's clear the cockatoos aren't interested in the yellow bin at all.

They're deliberately rifling through the red bin -- the one that gets them a free meal.

So there's a good reason for all this littering.

But how have they worked this out?

Scientist John Martin has been working with cockatoos for six years, carrying out experiments and fitting them with wing-tags to monitor what they get up to.

MARTIN: What we're seeing here is an example of how cockatoos have adapted to the urban environment.

After a bit of grabbing the bin and moving it around and then seeing that the lid opens, they did flip the lid open.

They did find the food reward.

Other birds then copied that behavior, and that information will be mimicked by other cockatoos.

Information is being shared, and that's benefiting all the birds in that group.

NARRATOR: The cockatoo's ability to solve problems and then share the solution is a very smart strategy for survival.

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

Some species have even displayed intelligence comparable to that of a four-year-old child.

This brain power, combined with a built-in inquisitive nature, is what scientists think is behind all this outrageous behavior.

To survive in a different environment, animals, like cockatoos, need to work out what benefits them, and that includes new food sources.

So that explains the littering.

But what about the cockatoo's reputation for casual vandalism?

♪♪ WOMAN: NARRATOR: Some birds have developed a habit of attacking wooden balconies.

RENEE: This has all been done by the cockatoos.

What they do is just peel pieces away, bit by bit.

Sometimes they get over enthusiastic and try to tunnel through the entire piece in one go.

NARRATOR: So, what is all this destruction in aid of?

In their forest home, Cockatoos regularly chew on trees and branches.

It helps keep their beaks sharp, and it's where they find bugs and grubs to eat.

Cockatoos are now 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 trial and error is causing extensive damage.

So, while the people of Sydney may see all this as a cockatoo crime wave... the birds are simply combining their natural skills and abilities to make the most of life in their new home.

MARTIN: In the urban environment, we often talk about winners and losers.

Sulfur-crested cockatoos are winners, they're a successful species because they're adaptive.

They're willing to take risks and try new things, they're exploring novel objects, and they're finding food resources and habitat in the urban environment where they didn't formally occur.

♪♪ NARRATOR: For these cockatoos, city living is working out well.

♪♪ [ Squawks ] ♪♪ They're clever, resourceful birds with a curious and exploratory nature... ...and these are exactly the qualities that have led them to succeed in this up-town world.

♪♪ Just like the cockatoos, rebels across the world are known to cause mayhem and mischief.

♪♪ But there's always a reason for their outlandish behavior in our urban environment.

[ Crashes ] ♪♪ South African Penguins take a fancy to beachwear and use it to feather their nests.

♪♪ North American black bears break into backyards... MAN: [ ] NARRATOR: ...where new climbing techniques and swimming lessons are important life skills.

From an elephant seal dealing with an unusual threat to his territory... ...to polar bears looking a little too close to home for their next meal... ...there's a survival strategy behind all these shocking animal actions.

♪♪ ♪♪ And some animals will do whatever it takes to get ahead in a new environment.

♪♪ Amongst the trees and forests of central Europe lives a secretive species -- the stone marten.

These small omnivores are relatives of otters and weasels.

Holding territories within the woods, they'll eat anything they can find.

They hunt small birds and rodents... and forage for fruit and berries.

♪♪ But some have realized there's one place that's much easier to find all the food, shelter, and warmth they need... ♪♪ ...the city.

So martens are moving in in ever-increasing numbers.

But now they're in town, these rebels are causing trouble.

♪♪ GERALDINE: One morning, I got into my car and drove, and then suddenly, the brakes didn't work.

SIMONE: When I opened the hood of the car, I saw that even the caps were chewed on.

NARRATOR: City stone martens have developed a new, alarming obsession.

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

You see scratches everywhere, little scratches.

You see here, the tubes have been completely cut off.

And they are afraid of nothing.

♪♪ [ Speaking foreign language ] NARRATOR: These vehicle vandals have made headlines across Europe.

♪♪ [ Siren wails ] They've become prime suspects for electrical fires... ...and they're been caught red-handed by mechanics.

♪♪ Stone martens are causing a staggering $75 million worth of damage every year in Germany alone.

[ Stone marten screeching ] ♪♪ Severed electrical cables and gnawed insulation isn't just a nuisance -- it's a very dangerous problem... ...and one that scientist Jan Herr haseen looking into.

HERR: So, we knew that martens went into cars and damaged them.

What we really wanted to know is why do they do this.

First of all, we saw very big difference in behavior between winter and then spring seasons.

In spring, suddenly, you find that the animals spend an awful lot of time in the road, and they really start running from car to car, checking them out, sniffing around on them, climbing into them.

And that is the same time of the year where you get a lot more car damage, as well.

♪♪ NARRATOR: For a stone marten, spring and early summer is a very important time of the year.

It's the breeding season.

Jan's research suggests their destructive behavior may all be connected by the need to secure a mate.

HERR: Martens are very territorial animals, and males will defend their territories in order to have exclusive access to females.

Like most carnivores, stone martens defend their territories by scent marking.

So, they use two techniques.

Either they use urine to scent mark, or they can also use small droppings.

♪♪ NARRATOR: An intruder will try to move in on another marten by leaving its own scent marks in his territory.

[ Stone marten screeches ] This can provoke a furious response from the original owner.

HERR: We're pretty sure that there's a link with territoriality.

So, once they're in an engine compartment and they come across a scent from a different marten, that they will have an aggressive response, they start biting around on certain parts.

NARRATOR: So, all this damage might be caused by a stone marten on the offensive.

But why do they only attack cars and nothing else in their territories?

HERR: In other environments, they would just scent mark rocks or trees or whatever.

At some point, they were starting scent marking cars, and cars are mobile features in their environment and they tend to move around, so the cars carry these scent marks from territory to territory.

NARRATOR: City residents are moving their cars between different stone-marten territories, and without realizing it, they're totally confusing the stone martens.

They can smell the scent of a rival marten on the new car in the area, and they think there's an intruder.

This sends them into a scent-marking frenzy as they attempt to regain rightful ownership of their patch, and it's our cars that pay the price.

But, of course, it's not bad news for everyone.

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

[ Laughs ] NARRATOR: As for the stone martens, they'll always defend their territory to the best of their abilities -- regardless of anyone or anything that gets in their way.

♪♪ These wild rebels are getting to grips with our urban world in surprising ways.

But in the fight for survival, there's a much bigger problem that almost every species must face... ...predators.

Almost every animal in the world has another that wants to eat it or just kill it.

♪♪ So one tiny crab in the Red Sea has devised an almost unbelievable strategy to stay alive.

Beneath the waves, amongst the corals, lives an extraordinary creature.

A sporting super star... [ Bell dings ] [ Canned punches ] ...the boxer crab.

♪♪ In a world where almost everything is big and dangerous, a tiny crustacean needs a fool-proof plan to stay alive.

♪♪ This pufferfish fancies his chances of an easy meal... ♪♪ ...but the crab has a secret weapon... ...the perfect pair of boxing gloves.

♪♪ A blistering left hook makes this fish think again.

[ Bell dings ] [ Canned cheers and applause ] And that's because those gloves are, in fact, sea anemones.

Tiny relatives of jellyfish, they have a cocktail of powerful toxins in their tiny tendrils.

Every time the crab lands a punch... [ Pow! ] ...the anemone delivers a painful sting.

The pufferfish won't try that again in a hurry.

But to survive, this prize fighter needs to keep its gloves in perfect working order.

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, stealing their food for itself.

Gripped tightly in the crab's claws, the anemones are hostages.

It's a ruthless but ingenious defense.

Even so, the crab's not completely out of harm's way.

These anemones have only ever been found living in boxer crab claws.

♪♪ Which means another rebel will inevitably try to pinch these precious possessions.

♪♪ ♪♪ ♪♪ ♪♪ In the struggle, the thief steals one of the anemones.

But this crab's not down for the count just yet.

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

It rips the anemone in half.

But this doesn't kill it, because, incredibly, anemones can survive being split in two.

In time, the boxer crab will regrow the perfect pair of gloves, and it'll be ready to roll with the punches once again.

♪♪ In this dangerous underwater world, the boxer crab has a sporting playbook full of sneaky skills, and it's helping it survive against the odds.

♪♪ [ Birds and insects chirping ] If some rebels have found very effective ways to defeat their enemies... ...others just aren't suited to confrontation.

♪♪ In the rainforests of Central America lives a creature that uses a very different tactic to survive... ...the three-toed sloth.

♪♪ Sloth by name and sloth by nature, with a top speed of around one mile per hour.

They're one of the slowest mammals on the planet.

Yet this lethargic lifestyle gives the sloth a big problem.

These rainforests are full of impressive hunters... ...from huge harpy eagles to deadly jaguars.

♪♪ To protect itself, this rebel is using a dirty trick.

♪♪ Rain forests are clammy, sticky, humid places -- perfect conditions for mold and fungi to thrive.

And, because they don't move very quickly, algae will even grow on a sloth's fur... ...turning them a delightful shade of 'rainforest green.'

But what's really interesting is that each hair follicle has deep grooves and cracks, which actively encourage this algae to establish.

But why would they want such a disgusting coat?

Well, the sloth's fetid fur may act as camouflage... ...helping to hide them 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 full of insects -- hundreds of them.

And one species in particular is a moth that can only be found on sloth fur.

This writhing, scuttling 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.

And while it might seem revolting, the sloth has actually adapted its whole lifestyle to make sure its fur is teeming with these insects.

Once a week, three-toed sloths make a perilous journey down to the forest floor... ...for a trip to the bathroom.

No other tree-dwelling animal does this, and it puts them at great risk of predators.

♪♪ Why do they do it?

Once again, it's those moths.

♪♪ When the sloth is on the ground, female moths hop off and lay their eggs in its feces.

The larvae then feed here, before they change into moths and find another sloth to live on.

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

And in turn, the moths provide the fertilizer for the algae in the fur, vital for the sloth's camouflage and survival.

♪♪ So, they may be slow and have questionable hygiene, but the three-toed sloth has devised an incredible solution to stay alive.

♪♪ [ Insects buzzing ] Some wild rebels take camouflage to a whole new level.

There's the hawk moth caterpillar that looks like a snake, a stick insect that pretends to be a plant, a leafy sea dragon sways in the kelp, and a leaf tailed gecko disappears against the trunk of the tree.

These extraordinary animals have adapted their whole bodies to hide in plain sight and con their enemies.

♪♪ But when it comes to survival, even one of the world's most dangerous predators uses a devious deception to avoid becoming prey themselves.

♪♪ This is the home of a snake with a truly terrifying skill set.

♪♪ The puff adder.

♪♪ With an attack speed of just a quarter of a second, armed with a cocktail of cell-destroying venom, hidden by cryptic camouflage, and tracking prey with a superb sense of smell, this rebel is the ultimate hunter.

♪♪ ♪♪ But even the puff adder is not without its problems.

Surprisingly, this venomous villain has over 40 different predators of its own, including the feisty mongoose and the fearsome honey badger.

[ Honey badger snarls ] ♪♪ So, to continue its reign of terror, it must avoid being eaten itself.

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

[ Tracker beeping ] A team from Wits University in South Africa recently made an extraordinary discovery on their camera traps.

A genet walks straight past a puff adder and a porcupine treads right on it.

These animals use their sense of smell to find food and locate danger.

Even in the dark, they should sniff out the snake.

How is the devious puff adder deceiving them?

♪♪ To find out, the research team has its own devious, innovative plan.

They've enlisted the help... ...of a meerkat.

♪♪ Using an exceptional sense of smell, meerkats find and attack a very daring diet... ...including venomous snakes.

They're the perfect scent detectives.

♪♪ First, scent samples are carefully collected from different snakes and then placed in small tubes.

One tube contains a control scent.

It's the smell of a sterilized, empty tank.

[ Tapping ] The meerkats will be given a food reward if they manage to recognize a specific scent.

Time to begin.

MILLER: Right now, I'm showing the meerkat what she's looking for.

NARRATOR: In this tube is the scent sample of a brown house snake.

To the meerkat, this will have a distinctive smell.

Now to find the matching odor in the tube line up.

♪♪ MILLER: There she's got it -- brown house snake.

[ Tapping ] NARRATOR: It now needs to find the matching tube for the puff adder scent.

But this time, it doesn't seem so easy.

MILLER: So, now she's indicating the control, which means she can smell the tank.

NARRATOR: The empty tank pretty much smells of nothing.

And she continues searching.

MILLER: She's also indicating puff adder, which means she can't tell them apart.

NARRATOR: By choosing both scent tubes, the meerkat is showing it 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.

MILLER: So, this is a form of chemical crypsis.

They're camouflaging themselves.

NARRATOR: This discovery is extraordinary.

The puff adder has evolved a kind of invisibility cloak for its smell.

This allows them to continue hunting and still stay safe from predators.

It's the first land vertebrate known to use this disguise for its own defense.

♪♪ But just how it does it is still a mystery.

♪♪ The puff adder has completely nailed the art of survival.

From fatal fangs to masterful deception, this is one devious snake in the grass.

♪♪ Hiding in plain sight is the perfect way to avoid predators.

But other animals need to be far more ruthless.

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

On the seashore, hidden in rock pools, live tiny animals with huge challenges to overcome.

Hermit crabs.

Unlike almost all other crabs in the world, the hermit crab doesn't produce its own external armor.

To protect itself from predators, it has to pick a shell to live in.

But the hermit crab is constantly outgrowing its home, and finding the right new shell on a vast beach can be a real issue.

So it has a lawless plan to get what it needs.

♪♪ Another hermit crab... and it has the perfect sized shell for our growing crab.

♪♪ There's only one thing to do.

Fight for it.

♪♪ ♪♪ But brute force isn't enough.

To win, the crab needs a new tactic.

♪♪ Using its own shell as a weapon, it attacks the resident owner.

♪♪ And the faster it raps, the more it's proving its strength and stamina.

It's deliberate intimidation.

Cowering inside, the victim tries to hold on.

♪♪ But our attacker has one final devastating move.

♪♪ ♪♪ It's a forceful eviction... ...that leaves the loser homeless... ...and the victor with the shell it wanted.

This maybe blatant theft, but the hermit crab's aggressive strategy pays off.

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

So, animals will do whatever it takes to outwit their enemies and stay alive.

But what if the threat to survival comes from closer to home?

From your own relatives?

Just off the coast of South America, one bird of prey rules the roost.

The striated caracara, also known as the Johnny rook.

♪♪ In spring, these birds feast 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 has been left on the sidelines.

Still too young to have its own territory, there's little access to the hunting grounds.

♪♪ But a youngster decides to chance its luck.

The adults take down any trespassers.

♪♪ [ Caracaras screeching ] ♪♪ [ Screeching continues ] ♪♪ [ Screeching stops ] The risk of injury in these brutal confrontations is too high.

Outwitting the adults requires a new plan.

Up on the moorlands, the young caracara isn't the only one in exile.

[ Caracara cawing ] New science shows juvenile caracaras use distinctive calls to rally together.

♪♪ This gang of teenagers are planning a rebellion.

♪♪ ♪♪ Working together, they invade an adult's feeding territory.

The balance of power shifts.

The adults can't fend off the entire mob.

♪♪ [ Caracara cawing ] ♪♪ Their smash-and-grab scheme has paid off.

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

Being forced to live on the periphery is tough, but for now, rising up against the adults is the only way to survive.

♪♪ Forming a gang helps the young caracaras get through their tricky teenage years.

♪♪ But other animals benefit by working together throughout their lives.

♪♪ Even when you live in a group, the best place to be is usually at the top of the hierarchy.

But to become the dominant animal takes clever, cunning, and sometimes shocking tactics.

♪♪ Deep in the African jungle... ...chimpanzees live together in large social groups.

Their day-to-day lives are relatively harmonious.

♪♪ But every now and then, the peace is broken... ♪♪ ...by the alpha male.

♪♪ [ Chimpanzee screams ] He will scream, display, and fight to maintain his position of power.

[ Screaming ] In Tanzania's Gombe National Park, scientist Michael Wilson has been investigating why alpha males use such aggressive strategies in their fight for leadership.

[ Chimpanzees hooting ] WILSON: For the most part, chimpanzees are a bit nervous around the alpha male, and the other males are pretty much always jockeying for position.

And the alpha male does his best to convince all the other males that he's the one they shouldn't mess with.

He's powerful. He's magnificent.

[ Chimpanzees screeching ] He may charge down a path through the forest and kick on a tree to make a big booming buttress bang.

NARRATOR: These lawless tactics secure his status.

And crucially, this gives him access to the perks of the job.

WILSON: The main thing that an alpha male chimpanzee is concerned with is making sure that he gets to be the first one to mate with fertile females, and that's really what his focus is.

[ Chimpanzee hooting ] NARRATOR: While it's often been assumed that the alpha male will care for and protect the chimpanzees in his group, the latest thinking suggests these dominant males are only in it for themselves.

Using selfish and aggressive tactics gives alpha males the best opportunity to have as many offspring as possible.

But over the years, researchers have reported some rebel alphas with a level of brutality that seems unusually high, even for chimps.

♪♪ So, can individuals have distinct and even sinister personalities?

One alpha, who reigned here back in 1997, was Frodo.

♪♪ Footage from the time shows how he maintained his position through a terrifying combination of intimidation and violence.

WILSON: He bullied the other males, he bullied the females, he bullied the people who were trying to follow the chimpanzees.

We were all afraid of him.

♪♪ [ Man grunts ] NARRATOR: Frodo was a ferocious fighter during attacks on other chimpanzee groups, and that aggression spilled over to anyone in his way.

WILSON: When I first got here, he followed me, and he just knocked me into the bushes and hit me with his fists.

It makes a really good spectacle.

It shows all the other chimps he was magnificent.

The next time I was in the forest with Frodo, I was really nervous.

Which I think is what life is like for most chimpanzees most of the time, 'Where's the alpha male? Is he gonna hurt me?

Is he gonna beat me up?'

NARRATOR: Frodo's behavior was extreme.

His attacks often seemed malicious and unprovoked.

It was as if he was being mean simply because he could.

WILSON: Frodo was just so big and powerful that he didn't seem to need anyone else's help.

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

It's, 'I groom you, you groom me.'

'You scratch my back, I'll scratch yours.'

With Frodo it was just, 'You scratch my back.'

NARRATOR: 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 a person acted similarly, some scientists might consider them to be a psychopath.

Roughly 1% of humans show psychopathic traits -- characterized by the lack of morals and empathy, with fearlessness, ruthlessness, and volatile aggression.

New research is revealing that, like us, individual chimpanzees do have distinct personalities, and so some may be more inherently violent than others.

WILSON: It can be shocking to see chimpanzees attacking and killing each other like this, and we tend to see chimpanzee behavior in very moralistic terms because they look and act so much like people.

But if we think about it in terms of what chimpanzees need to do to succeed in their environment, this is one way of achieving that goal, and it looks to be a very successful strategy for chimpanzees.

♪♪ NARRATOR: For alpha-male chimpanzees, being a bully comes with the territory.

These rebels are doing whatever they need to do to get the greatest reward when it comes to survival.

♪♪ ♪♪ When the struggle to stay alive is a constant battle, it's no wonder animals will turn to devious tactics.

WOMAN: NARRATOR: Whether it's a cockatoo with a taste for vandalism... WOMAN: NARRATOR: ...a crab holding anemones hostage... ...or even the horrible hygiene of a three-toed sloth... ...these rebels will go to remarkable lengths... ...in the drive to survive.

♪♪ ♪♪ Next time, we meet nature's love rats.

The sneaks... cheats... and the downright freaks.

Doing whatever it takes to find a mate and bring up baby.

♪♪ NARRATOR: In the natural world, creating and raising a family is a big challenge.

To succeed, some animals will resort to clever cons and dirty deeds.

These are the planet's greatest rebels -- the kidnappers, sneaks, and cheats who will stop at nothing to find a mate.

♪ Rebel, rebel, you've torn your dress ♪ ♪ Rebel, rebel, your face is a mess ♪ ♪♪ ♪♪ ♪♪ ♪♪

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