Original subtitles

[narrator] Loners. The strong, silent types.

Loners that have everything they need to get the job done.

[narrator] They're solitary, reclusive...

They're not trying to be around others.

But if they come into contact,

some type of fight might begin.

[narrator] But "me time" isn't all the time.

Whether it's a deadly tango

or an apex alpha at a table for one...

They don't just look like a leopard,

they act like a leopard.

[narrator] It may not be fast...

That is a boulder with feet.

[narrator] ...but it's always furious.

They smash it against the surface of the water

to rip it apart.

[narrator] Everyday, everywhere,

our planet is a battleground.

Turf wars,

food fights,

and mating mayhem rage on...

as animals outwit and outmanoeuvre their own kind

in Battle of the Alphas.

As the wind blows across the Galapagos Islands,

the native giant is doing what he does best.

It is a very easy, sedate life for the Galapagos tortoise.

They spend at least 16 hours a day doing...

nothing.

[narrator] While the Galapagos finches feed on his parasites, the giant tortoise can wait.

This loner can pass an entire year without eating

or drinking anything.

But today he's hungry.

Which is why he's on the move.

He's on the path to his cactus tree.

By acquiring this cactus tree, acquiring this food,

they're also having this second benefit

of potentially luring females closer to them,

which would benefit in the mating process.

[narrator] But his cactus tree is on the other side of the island.

And his top speed is six kilometres...

a day.

It takes time to move a boulder up a mountain.

The giant Galapagos tortoise totally lives up to its name.

They can reach five feet in length.

And about 230 kilograms, about 500 pounds.

That is a boulder with feet.

[narrator] Our hero is making headway.

But there's a problem.

Another male tortoise is on the path.

Don't forget these are loners.

They're not trying to be around others.

But if they come into contact, some type of fight,

some type of altercation might begin.

[narrator] The tortoise alphas must still compete

for resources and for the attention of females.

The adrenaline starts pumping... slowly.

These animals will fight quite regularly.

It's just you might not notice them doing it.

It's a little bit subtle and it's a little bit boring.

When we think of fights, we think of punches

and we think of thrashing.

It is essentially the world's longest staring contest.

They're glaring. They're really making direct eye contact.

Their mouths are gaping open.

It's not what we would think of as a fight,

but to them, they think it's a fight.

[narrator] Then again, these combatants

put the emphasis on "veteran".

On average, they're living to be about 100 years old,

which is already mind blowing for us, humans, us mere mortals.

However, they actually have been known

to live up to 175 years old, which is crazy.

[narrator] Imagine being 175 years old

and carrying your house on your back while fighting.

The giant Galapagos tortoise's shell is not as heavy

or as cumbersome as you might think.

It's really just a cluster of these honeycomb shaped structures

that contain air chambers that can actually sometimes

make it easier for the turtle to walk and move itself.

[narrator] And fight... tortoise style.

As huge as he is,

even this giant knows he's out-bigged.

The defensive turtle might then have what is called a head withdrawal,

when it actually will tuck its head into its shell

and really bottle itself up much more tightly.

[narrator] That hissing sound is not an expression

of animal emotion.

It's the sound of air escaping the lungs

as the tortoise draws his head inside and closes the shutters.

If a fight continues to escalate

that's the point where they draw their swords, if you will.

But in this case, their swords are actually their necks.

Really, what's key here is their incredibly muscular necks.

And their necks aren't necessarily muscular

so that they can hold up their heads

cause their heads aren't very heavy or big.

But the reason they have these muscular necks

is so that they can extend and withdraw their neck

very quickly.

They will come together face on

and then look to extend their necks as far as they can.

[narrator] Those mouths can rip into a cactus.

But a bite is the least of their concerns.

They're just trying to show each other who has the longer neck.

Nothing to do with their overall body size,

but the height that they can get their neck to.

That is what determines the victor.

That one is always the winner.

[narrator] Our prickly hero gets to have his cactus

and eat it too.

There is some consolation for the loser.

You have less energy, you move slower, but you live longer.

[narrator] He has time on his side.

[intense music]

From ancient outsiders to slithering solitaries.

Spring in Gloucestershire, England

A male European adder.

All alone with a bad hangover.

He's recovering from the snake version of hibernation.

You'd have thought there'd be two things that they most want to do:

eat and find a mate.

But that is not the case. The first thing they must do

is warm up and bask.

[narrator] The European adder is the most northerly

venomous snake in the world.

So sunshine is a precious resource.

He doesn't want to deal with anybody else.

He just wants to lie in the sun

and build up sperm so that he can multiply.

They need that sunshine to actually maturate the sperm,

so that they can then go and find a female and mate with her.

[narrator] Snakes don't rely on eyesight.

Finding a mate is more a matter of common scents.

When they flick that tongue out and they whip it through the air,

the tongue will collect particles of scent,

these chemical signals. It's then brought back into the mouth,

and it's stuffed up into a chamber above the mouth

called the Jacobson's organ.

It weighs up pretty much the amount of chemical on

this lobe versus this lobe of the tongue.

And if there's more on the right than there is on the left,

it sends a signal to the brain saying turn right.

But the one slight issue is

there'll be a number of male adders

that may well have picked up that same pheromone

from that very same female who will be thinking,

"This is my opportunity to mate."

[narrator] And when they do, the race is on.

They will make a beeline to any potential female.

[narrator] Time to prove who is the badder adder.

Now there are a number of rules.

First and foremost, of course, they have no legs and no arms,

so there's no punching each other and no kicking each other.

And it's wonderfully described as an adder dance.

Because they will go face-to-face

or they will go back-to-back.

[narrator] These legless dancers can stretch

85 centimetres.

They will rear up, at least half the snake will come up,

and they will often entwine belly-to-belly

or get completely coiled together.

[narrator] There's one weapon an adder won't use

in a fight with a rival.

The one thing they don't do is bite each other.

And it's interesting they don't use their most formidable weapon

because they could be wasting venom,

which is energetically expensive to make.

And they don't want to be wiping out their own species

and leaving just female adders around.

[narrator] Is it the tango? Or is it the twist?

It's a pushing and shoving match.

And frequently they'll fall over, and they'll rear up again,

and entwine, and then push each other right down again.

If you win this dance, you've got a chance to have kids.

And for the most northern of all the vipers,

that is very, very important.

And eventually, slowly, one will start to dominate.

And that basically comes down to this test of stamina

and a test of strength.

The heaviest snake is the one that is the most successful

because he's got more leverage.

He can get higher into the air

and beat his opponent down into the ground.

[narrator] At last, the loser slithers off.

But the alpha isn't home free.

It's a tough environment living this far north latitude-wise.

And quite often the females will only rear young

at best every couple of years.

[narrator] To aid in mating,

the male adder is blessed with not one but two penises.

And the male actually has what's called hemipenes.

He has two hemipenises.

They look just like a small "V",

and he only uses one of those hemipenises to mate with.

[narrator] When it comes to mating position and frequency,

scientists theorize that two is better than one.

He'll insert into the female's vent,

and it's not a quick process. It can last several hours.

This is also a really good way of keeping other males away.

Because if you're taking a long time to mate with a female,

it means that other males can't mate with her.

So the longer you can take making love to your lady adder,

the better.

[narrator] But the northern sun is warming more males.

More challengers.

And the female adder has her own agenda.

She wants the best for her eggs, the absolute best.

But that might be from three or four or five males,

so she'll breed multiple times with the best of the best.

[narrator] These snake babies may each have

different daddy adders...

but the winners will never know their sperm was not alone.

[intense music]

From solo snakes to lonesome lizards.

Southern Europe.

The lacerta lizard.

Normally, they love to sunbathe alone.

But these days, the males are restless.

Because even the most solitary lizard needs another lizard

at least for a short while.

And that's all the time he has.

Their mating season, their period of time they have to mate,

may only be about one month. But in some cases,

it's actually been reported as short as 17 days.

And with that kind of pressure to...

set your genes on for the next generation,

males are willing to go to great lengths

to bag themselves a female.

[narrator] And that means fighting.

They're incredibly aggressive when it comes to

their mating season and courtship.

[narrator] The first close encounter.

A showdown for show-offs.

They're trying to look big.

They're trying to look ferocious.

Because size in lizards really does matter.

[narrator] Larger males can reach 20 centimetres in length.

If one's clearly larger, the other one's likely to back away.

[narrator] Colour is another alpha marker.

Lacerta lizards get greener as they age.

So, the greener the lizard, the more seasoned the mate.

And so that's also why we see younger males

typically reproducing less than older males

because again, that green colour is really

what's attractive to females.

So the males, if they see someone who is as green as them,

or maybe even greener, well they will go green with envy.

[narrator] And as they get greener, they get meaner.

They're both maybe eyeing the same female.

They're going to show a lot of different forms of aggression.

So one might be that they arch their backs.

One might be that they really puff out their throat.

[narrator] That's the threat display the human eye can see.

But the competitor sees something we cannot.

Science has found that the throats of very healthy,

very successful males have a higher UV reflectivity

than those of less successful males.

We have scientific backing showing

that when a male has less UV reflectivity,

it is more probable that it is going to be the individual

to back down from a fight.

It's essentially a way of saying,

"I'm fit, I'm healthy, I get loads of food,

and to show that look how much UV I can reflect from my chest."

Because that costs biological money

to put on that kind of internal sun cream.

[narrator] If the two rivals are mutually green and mean,

things get rough.

These lizards will actually flip each other over

and it can be pretty aggressive.

They're scratching. They're wrestling.

They're looking to overpower and pin their opponent.

And they're going to use their mouths to do that.

That's the best tool that they've got.

So they're looking to bite around the head,

around the neck, force the opponent down

and get them to submit and accept that

they're bigger, badder, and better.

And actually, we have seen that older lizards that have,

you know, been through it for more time than younger lizards

will have scars, you know, and previous lacerations

noticeable on their body.

These battles can actually result in really significant damage.

[narrator] Like a severed tail.

Scientists believe the tail continues twitching

to distract attackers.

But even a missing tail is not the end of the love story.

This alpha lost a tail and he's still found a mate.

He now directs his aggression into courtship.

So what they tend to do is attack the female,

which sounds completely insane,

but it's more of a love nip than a full-on bite.

And they will start biting the female around the base of her tail.

Often that's to position the female to ensure that

she's in the right angle for him to effectively mate with her.

[narrator] But the male lacerta is not in the clear.

There is a bit of a catch. Ultimately,

the male that breeds or mates last with the female,

that's typically the one that's going to fertilize that female's offspring.

And so, because of that, these lizards will actually

partake in what we call mate guarding.

[narrator] By preventing any other male from mating with the female,

this lizard is covering a lot of bases.

It serves lots of purposes. It is a marking territory.

It's saying, "Look, this is my mate.

Back off, you know, I've got this close.

Don't bother. I'm going to mate with her."

They're aggressive before mating.

They're aggressive after mating.

And they're pretty much just going to be aggressive

for that entire 17-day-to-one-month window they have

to initiate this courtship behaviour

and propagate their genes.

[narrator] Mission accomplished.

This lacerta can enjoy his solitude once again.

All species fight their own kind...

But for the top of every food chain,

there is no contest,

this is an apex alpha.

[***]

With a reptilian-like head,

menacing teeth,

and a killer appetite,

leopard seals are one of the most dangerous predators

in Antarctica.

When it comes to finding food,

leopard seals don't need help from their friends.

They are perfectly capable solo artists.

They're loners that have everything they need

to get the job done by themselves.

[narrator] Of the six species of seals that live in the Antarctic,

leopard seals are the most fearsome.

They don't just look like a leopard.

They act like a leopard.

They are seriously dangerous predators.

In fact, they are one of the top predators

that you will find in the Antarctic circle.

They eat pretty much everything and they have nothing

to worry about except for maybe the occasional orca.

And even then, if the leopard seal is close enough to land

or a big lump of ice, it can jump out

and wait until the orca gets bored.

That's a pretty handy escape method.

I mean, the leopard seals are at the top.

[narrator] And they've got one brutal behaviour

that sets them apart.

They regularly hunt other seals

They are so big, they are so powerful,

that they will eat the babies of other species

that live in their habitat.

[narrator] This is an adult female.

She's a big girl and she's looking for supper.

The females get bigger than the males,

and the females will potentially do three and a half,

perhaps pushing four meters.

Males are usually a bit smaller, 'round about two meters.

So it is a seriously sized beast.

[narrator] She's patrolling a tidal cove.

A spot she chose deliberately.

It's summer in the Antarctic

and rocky beaches are teeming with new life.

We see with things like penguins

and also things like polar seals,

that they have very specific areas of Antarctica

that they regularly come and go from.

These are like the highways of Antarctica for these creatures.

So the leopard seal knows

where the most business is going to be.

[narrator] Not only has she picked the spot,

she's chosen the time too.

They know which prey to go for at which time of day.

So if it's nighttime, they can get krill

that are coming up closer to the surface.

But during the day,

that's when it goes into full-leopard predator mode.

So it likes to stalk its prey.

It's an incredible ambush hunter.

It's very intelligent, and on the menu

are things like seabirds and fish.

But the prize meat, the creme de la creme,

are the penguins and the baby seals.

[narrator] Which is exactly what she's here for.

A fur seal pup, just a month or two old,

not yet wise enough to know what lurks in the shallows.

So the leopard seal will stalk these pupping grounds

where the seal pups are just keeping its eyes

and the tip of its nose out of the water to be able

to breathe, take in the scents, keep an eye on its prey.

And it will wait until one of the pups has got close enough

to the edge of the water that it can literally leap from the sea,

grab one, and pull it back in.

[narrator] It's a hunting strategy they use specifically for pups.

When penguins are on the menu, they switch it up.

Leopard seals will hide underneath the ice

on the edge of the ice shelf just where the penguins

are about to jump in.

And as soon as they do jump in,

the leopard seal will strike out from under the ice,

from undercover, and grab hold of one.

It's an apex predator that has a whole bunch of tools in its toolbox

for how to take down different kinds of prey.

[narrator] This ravenous female makes her move...

Her jaw opens wide then clamps down hard.

Leopard seal is a huge animal,

but the real trick to its success is its mouth.

I mean, that's really the business end.

It has the longest jaw of any seal in the world,

and it can open that jaw incredibly wide.

That means that they can access a whole range of prey.

You don't want to be in an area like the Antarctic,

where every meal counts, and come across something

that you cannot physically eat.

The leopard seal doesn't worry about that.

[narrator] Her 2,5-centimetre-long canines

pierce deep into the pup's hide.

Then, she begins thrashing.

Leopard seals have a mouth.

They don't have hands.

They don't even have shearing teeth to cut things up,

so to chew the meat up.

So to take an animal apart, they are pretty ingenious.

They take the animal and they smash it

against the surface of the water to rip it apart.

And if they didn't have that genius strategy,

there'd be no way to actually get the food into their bellies.

[narrator] It looks ruthless and exhausting.

After smashing a meal to smithereens,

you might think it's time for a break.

But no, this apex alpha just keeps going.

They basically feed nearly all day.

In fact, the average foraging/feeding period

for a leopard seal is around about 17 hours.

So they are always on the munch.

[narrator] Female leopard seals have been recorded

catching up to eight penguins a day

and as many as four pups an hour.

Female leopard seals are so successful at what they do,

that one study has shown that 75 % of hunts result in a kill.

And that is pretty good going.

[narrator] They don't miss and they don't share.

Males are rarely seen at the same hunting grounds.

Now, the male leopard seals really don't get a chance

to hunt seal pups.

The seal pupping grounds are the best territories,

so they've not got a hope of displacing a big,

powerful female.

But even then, among the female leopard seals,

studies have shown that it's only a very small cadre

of massive, dominant females that control

all the hunting grounds of the seal pups.

[narrator] This lone hunter has finally had her fill.

She hauls out to rest.

And while she may look clunky here,

when she returns to the water she'll once again transform

into a ruthless, calculating predator.

Untapped venom,

solitary confinement,

ancient warriors...

Teamwork has its advantages.

But for some alphas

battle is strictly DIY.