(wind roaring)
The peak of the last Ice Age
was one of the coldest periods in Earth's history.
The Americas were closed to the rest of the world
by a wall of ice over a kilometre thick.
South of the glaciers, grassland still dominated.
Huge herds of prey were laid bare for a host of hunters.
Smilodon, with its enormous fangs, lay in ambush.
(dramatic music)
Pack-hunting homotherium tackled the largest of animals.
For millions of years, the sabretooths had been
the world's top land predators
but this was their final stronghold.
In the rest of the world, the big cats had replaced them,
while in the Americas, the cats still lived
alongside the sabretooths.
But cataclysmic change was coming for them all.
The world's last sabretooths would soon vanish
while the big cats survived.
Why them, what's their story?
What were the unique adaptations that gave big cats
the edge in this final battle for survival?
How did the puma come back from the brink of extinction?
Why is the leopard, perhaps,
the greatest survivor of them all?
(dramatic music)
North America, 20,000 years ago.
It was the Pleistocene Age
when the open landscapes were ruled by giants.
The skies were filled with huge birds,
some with five-metre wingspans,
all waiting to scavenge the numerous kills.
The Americas were the only place on Earth
where ferocious sabretooths still existed.
Here, they lived alongside big cats, the biggest ever.
American lions could face the sabretooths
on their own terms.
(roaring)
There were so many predators on the plains,
some of the prey sought refuge in hills and rocky outcrops.
Here, there was another more secretive hunter
waiting for them.
The puma.
It was a big cat with an average weight of 60 kilos
but was dwarfed by smilodon and the gigantic American lion
that could weigh as much as 400 kilos.
Unable to compete on the plains, the puma found a living
in hiding using cover, stealth and its wits to survive.
We know from fossils, pumas have lived in the Americas
for at least 500,000 years.
However, its ancestors were once found
across Europe, Asia and even Africa.
As the ice sheets fluctuated, seas rose and fell,
and these cats were able to cross the Bering Land Bridge
from Asia and into the Americas.
In North America, where they're known as cougars
or mountain lions, their situation now is not that different
to their Ice Age ancestors.
Although the sabretooths have gone,
pumas still live in fear of predators.
(howling)
Wolves dominate the open country,
while in some places, human hunters make it dangerous
for these cats to even show their faces.
This is why pumas are still so secretive and elusive,
crucial qualities in their survival story.
Observing the behaviour of modern pumas gives us a window
into their past and an insight into how
they might have survived in Ice Age America.
In this remote cave, a mother has raised three cubs.
They're a few months old
but still too young to hunt for themselves.
Their mother leaves them behind
in the safety of the den while she finds food.
Here in Montana, mule deer are a favourite.
Pumas are experts in stealth
and low light levels give them an extra advantage.
(dramatic music)
The lucky one gets away.
(birds squawking)
Camera-trap images, filmed with invisible infrared light,
reveal nocturnal behaviour that has rarely been seen.
At first, this mother spends an hour
plucking fur from the deer
before she opens the kill to make it easier for the cubs.
She then covers the deer with the fur she's just plucked
to hide it from scavengers
and returns to the cave to collect her family.
The cubs are safer now under the cover of darkness.
Analysis of tooth wear of modern pumas
has revealed close similarities with that of Ice Age pumas,
suggesting they had a similar diet.
These cats will consume virtually everything on a carcass,
stripping gristle and tendons from the skeleton,
unlike the extinct Smilodon, which had surprisingly weak jaws
and long fragile teeth, ill-suited to grappling with bones.
Although, the puma was smaller in size,
its short face and smaller canines
gave it a more powerful bite -
perhaps one reason why the puma is still with us.
But during the Pleistocene, the puma's thrifty eating habits
and ability to live under the radar
couldn't save it from what was to come.
At the end of the last Ice Age, the thick ice sheets
that covered much of the Northern Hemisphere were melting
and an ice-free corridor opened up between Asia and America
as it had done repeatedly over millions of years,
allowing the movement of animals in both directions.
On this occasion, elk migrated from Asia.
And, for the first time in history,
now they had clothing for extreme cold weather.
Modern humans also made the crossing.
(dramatic music)
Within a few thousand years of their arrival,
about 75% of the large animals in North America vanished,
including the American lion
and four other species of big cat
and the very last sabretooths on earth.
Even the puma wasn't spared.
There's strong evidence that humans were the cause.
Large, slow animals such as mammoths and woolly rhinos
would have been easy prey for these pack hunters
armed with spears.
With keystone species like mammoths now missing,
grasslands, that were once close cropped, became overgrown
and choked with dry vegetation.
Wildfires are believed to have spread across the continent,
burning vast amounts of these uneaten plants,
destroying delicate ecosystems that had endured
for millions of years.
It was a catastrophe.
(bird screeching)
In South America, similar events took place
with the complete annihilation
of almost all the large animals.
But somehow a small population of pumas managed to survive
and they were the ancestors of all pumas alive today.
(dramatic music)
In southern Chile, there are places
where you can still see Pleistocene survivors -
among them, guanacos,
one of the few camel species still with us.
(screeching)
Cruising over the herds,
a giant scavenger, the Andean condo,
searching for the remains of a predator's kill.
And the top predator here now is the puma.
The open-country guanacos would not have been on the menu
for pumas in the Ice Age.
But now that the sabretooths have long gone,
here the puma has no competition at all
and it has found a whole new world it can claim as its own.
(dramatic music)
In Torres del Paine National Park,
a mother can take her cubs into open country
in broad daylight,
in a way that her ancestors could only dream of.
(dramatic music)
Soon after the Ice Age ended,
guanacos swarmed in their millions
over the grasslands of Patagonia
and pumas had the chance to learn a new skill,
hunting on treeless plains.
(dramatic music)
Today, these cubs are about to learn that lesson too.
Their mother leads the way.
Without cover, stealth is essential.
She expertly stays hidden while closing the gap
between herself and a guanaco.
The cubs are keen students and try to copy their mother
by creeping after her.
They're making all the right moves.
But have yet to realise they're also supposed
to be invisible.
(screeching)
Before they're even close, they're spotted.
(screeching)
The guanaco's distinctive alarm call warns others nearby.
It was a valuable lesson on the importance of stealth.
In daylight on these open plains,
even experienced pumas are tested to the limit.
This young female has got the hang of concealment.
Her padded paws, typical of all the cats,
allow her to move almost silently.
But she needs to get just a few metres from her prey.
(screeching)
She charged too soon.
Perhaps, at night she'll have more success.
As the sky darkens, guanacos move to a new location,
sometimes gathering into large herds.
They always sit down for the night,
staying still and completely silent but on high alert.
The puma needs to find a herd before it's too dark.
Despite her superb night vision,
the guanacos can be very hard to see
unless they're moving.
Special night cameras give us a clearer view.
In the faint moonlight,
the hunter merges with the background
until she reveals herself against the sky.
(screeching)
But she can hear where the herd is going.
Once the moon is completely covered by clouds,
the puma has the upper hand.
(screeching)
The herd panics but, in the darkness,
they are too scared to run far.
She can take her time to choose a victim from the crowd.
At over 100 kilos, the guanaco is double this puma's weight
and is far more than she can eat in one go.
Yet she wants to keep her prize all to herself
so attempts to conceal it.
The hunter stays close to guard her spoils.
But she can't hide the smell of fresh blood.
Before long, two other pumas arrive.
A huge male
and another female.
The new female helps herself to the kill
while the male takes a back seat.
The hunter is not happy.
She comes to investigate the intruders,
both of them older and more experienced than her.
The hunter skirts around the edge of her guanaco.
She uses typical cat language
to show she doesn't want to fight.
A blink and a look away.
She waits.
The male, at twice the weight of the females,
has the power to drive them off, but he does nothing.
Close by, there are more pumas.
A mother and her three almost full grown cubs
are taking a keen interest.
They approach.
One of the cubs gets close to the kill.
Suddenly, the male's posture becomes aggressive.
The mother moves in to defend her cubs,
(growling)
but he doesn't avert his stare,
(growling)
and asserts his dominance.
The cub stands his ground.
The male could easily kill them
yet withholds his full power.
Perhaps, the cubs are his.
He scent marks the ground
and then lets the family feed.
The hunter picks her moment.
Finally, she gets to feed on her kill too.
There are now seven pumas around the guanaco.
Events like this are very rarely witnessed
and give us a dramatically different view
of the cat we thought we knew.
Pumas have always been thought of as solitary,
but these are acting more like a pride of lions.
Researchers believe when prey is abundant,
they may be willing to share their kills
rather than risk injury through fighting.
(dramatic music)
A few hundred years ago,
there were about 30 million guanacos on these plains
and early European colonists reported seeing
prides of pumas feasting on kills.
So, perhaps, this is just normal behaviour that disappeared
when the guanacos were hunted out.
In some places here, puma numbers have now risen
to almost one cat per square kilometre.
This National Park has become a crucial refuge.
From here, young pumas can follow their prey
onto ranch land and beyond.
Like all cats, pumas are wanderers
and can live in almost every kind of habitat
including frozen mountains,
deserts
and rain forests,
which is why after the last Ice Age,
they managed to rapidly re-colonise North America
from their southern refuge.
Although over the last few centuries
their population has shrunk dramatically,
the puma is still the most widespread cat in the Americas.
They've even begun moving into our settlements.
The puma came into a world already full
of dangerous predators and found its own way.
It survived an extinction that wiped out its competitors
then went on to conquer the Americas for a second time.
But there's another cat on the other side of the world
that also shows an extraordinary determination to survive
and whose story is, perhaps, even more remarkable
than that of the puma.
(dramatic music)
The leopard.
It too can live in almost any kind of habitat.
However, this cat excels at living alongside us.
During the Pleistocene, it was found from Africa to Europe
and all the way to Japan.
Today, the leopard's range has shrunk,
but it still has the greatest global spread of all cats.
While the sabretooths are long gone,
the leopard has to survive in a fearsome world of predators.
Now, humans, tigers and lions are its biggest threat.
(roaring)
(dramatic music)
(roaring)
And for the leopard, just as for the puma,
its best to keep out of the way of more powerful enemies.
(screeching)
Here in Sri Lanka to the south of India,
there are as many as 1,000 leopards.
And with no lions or tigers on the island,
the leopard is top cat.
But it's still not in charge.
The prey animals don't make it easy.
Wild boar are sometimes on its menu,
but they're also meat scavengers.
She's outnumbered.
(squealing)
Once it gets dark and there's only one pig left,
the leopard takes its chances.
(dramatic music)
But this Bolshi pig isn't afraid of cats.
(dramatic music)
The only way a leopard can ever get a meal here
is with complete surprise.
And it's not easy when your cover is blown.
Even the buffalo don't want it around.
The leopard's life is one on the run.
It usually has to live in the shadows,
something that, perhaps, of all cats, it is best at.
Its skill at secrecy is why it is so successful.
Leopards have survived for millions of years
by adapting to an ever changing world.
Observing their behaviour today can help us understand
why they are the cat with the best chance
of adapting to the future.
They can reproduce when they're about two years old
and live for about 12.
So, they have a limited window to procreate
and ensure the survival of their genes.
When you're an elusive and solitary cat,
it can be a challenge to find a partner
in a complex and dense forest.
(birds and insects chirping)
(growling)
The female helps the male track her down by calling loudly.
(growling)
Her tantalising scent trail, infused with hormones,
provides him clues to where she's been.
(gentle music)
When the courting couple finally meet,
they'll be inseparable for several days.
Under the light of the full moon,
we can observe rare footage of this lover's tryst.
Her caresses are tender.
But mating can be a violent affair.
All male cats have a barbed penis to stimulate ovulation.
So, this male bites the female's neck
to protect himself from attack
as withdrawal can be quite painful for her.
(growling)
He jumps to safety.
While the female's in season, they can mate 250 times
in a couple of days -
as often as every 15 minutes,
to maximise reproductive success.
Given half a chance, all big cats can breed quickly,
but here leopards can't even mate in peace.
After millions of years of being hunted by larger predators,
elephants won't tolerate cats nearby.
(growling) (elephants trumpeting)
Being shunned and chased by other wildlife wherever they go
hasn't stopped leopards here in Yala National Park
from doing very well.
This is one of the densest leopard populations in the world.
But one of the key reasons
for their success here is surprising.
Humans have provided a helping hand.
There are few natural lakes or ponds in Sri Lanka.
For centuries, wildlife here has depended
on manmade water sources.
But, unlike the puma pride of Torres del Paine in Chile,
the leopards here are so antisocial
they each want their own place to drink.
The limit to the leopard population in Yala
wasn't the availability of prey, it was water sources.
So, in Yala, more artificial water holes were built
in the hope that they could increase the number of leopards.
So far, the experiment has been a success.
Leopards are thriving here.
(birds and insects chirping)
Throughout their range,
leopards have been living alongside humans
for nearly two million years.
Now, their relationship has got even closer.
They've learnt that if they keep a very low profile
and can find food of some kind,
they can survive among people.
Sometimes, communities are completely unaware
of a leopard in their midst -
only the village dogs know.
But there is one place in India
where these 21st century cats have taken living among us
to a whole new level.
Mumbai.
(traffic roaring)
The most populous urban area in India
with over 20,000 million inhabitants.
(fireworks popping)
And incredibly, also home to leopards.
Within this huge metropolis
lies Sanjay Gandhi National Park.
A protected area of around 100 square kilometres
would normally be expected to support
only a few leopards, but here, there are over 40.
When most residents are asleep, these elusive hunters
make their way out of the park into the city.
Cubs also learn the route from an early age.
This is their urban jungle.
The leopards don't have to go far
to find what they're after.
An abundance of food.
These cats are known to feed
on about a hundred different prey species.
This ability to eat whatever they can catch
is a key reason why they're so successful.
But, here in Mumbai, 40% of their diet
is formed by an animal you wouldn't expect.
Leopards are so good at staying out of sight
that few people witness this night hunter's activities.
Surveillance cameras reveal the truth.
(dog barking)
There are 95,000 dogs in Mumbai
and the leopards know where they live.
The element of surprise is essential.
That leopard silences its victim with a throat bite
before it can make a sound.
With such a high density of people,
encounters with leopards are inevitable.
Only a very small proportion of these
result in injuries to leopards or people.
This pregnant female was filmed
on our remote camera after midnight.
A short while later, this man walked the same path.
80% of incidents happen after dark
when people wander outside to answer the call of nature.
But it's when leopards are cornered that they will attack.
(men shouting)
In towns and cities across the country,
leopards get themselves into unfamiliar territory,
(growling)
showing the sheer strength and determination to survive
that got them through the last million or so years.
(people shouting)
A leopard on the loose attracts hordes of spectators,
all eager just to get a look at this most elusive
of their neighbours.
Keen to protect both people and leopards,
the Indian wildlife authorities generally dart the cat
and take it back to the forest.
For the leopards, Mumbai is their home too.
It's incredible that not only can they survive here,
but also that this is, in fact, the densest population
of leopards in the world.
Leopards with all their skills of stealth and concealment
demonstrate that big cats can live alongside us.
For all of these cats, adapting to a changing world
was crucial to surviving the Pleistocene,
and now they need to draw on those same abilities
in the modern world.
(dramatic music)
In the Indian state of Gujarat,
the last remaining Asiatic lions have taken up residence
in rural areas.
100 years ago, the Gir Forest was their last stand.
(growling)
There were just 20 left.
Today, there are about 650 of them
spread over 20,000 sq kilometres
of densely populated farmland.
Gir National Park was once a savannah
populated by deer and antelope.
Now a thick forest, most of the lions have moved out
following their prey onto nearby farms.
Our night vision cameras show how they hunt
in the open fields after dark,
just as they did on the Indian savannahs of the past.
The lions actually protect the farmers' crops from pests.
(screeching)
(growling)
When they do occasionally prey on livestock,
the reaction of the villages is very surprising.
The Gujarati people have a deep respect,
tolerance and even reverence for them.
They are proud of their lions
and feel honoured by their presence.
(people chattering)
What these lions and the Gujaratis demonstrate
is to them perfectly normal
but, to most people on the planet, is revolutionary.
Big cats and humans can live together.
(dramatic music)
While there has been a global change
in attitude towards big cats over the last few decades,
very few places exhibit the kind of tolerance
and respect on display in India.
Most populations are still declining rapidly.
Jaguars have been eradicated
from half of their historic range.
Tigers have lost a shocking 96% of their distribution
with fewer than 4,000 remaining,
while some estimates put the snow leopard population
at less than 3,000.
Seven species of big cat have clung on to survival
for more than two million years,
thanks to their special skills.
For most of our past, they were our enemies and competition.
But they have stayed with us
all the way through our own journey.
In fact, we inadvertently helped them.
It was us that led to the demise
of their main competition, the sabretooths.
We killed off their prey.
We're in danger of doing the same thing
with the few big cats we have left.
Only now that we are about to lose them,
do we realise that we want them to survive.
And we are only just beginning to understand
how the lives of predators and their prey are linked.
If we want wildlife at all, we need cats.
With tolerance and understanding,
they could could prosper once more in a new age of big cats.
(dramatic music)