(hyenas barking)
(gentle music)
During the Pleistocene Age,
much of the earth's land was covered
by short, grass steppes, including Africa.
Huge herds of prey were laid bare
for a host of hunters.
(suspenseful music)
The fearsome Sabretooth Megantereon,
with its enormous fangs, lay in ambush.
(suspenseful music)
Two species of hyenas tested the herds
for signs of weakness.
(suspenseful music)
Jagged toothed Homotherium, pack hunting Sabretooths,
were rampant across the world.
From Africa to the Americas.
(suspenseful music)
They were after something big,
really big,
like a young, straight-tusked elephant.
(suspenseful music)
(elephant wailing)
For millions of years, the Sabretooths and hyenas
have been the world's top land predators.
But new forces threaten the old order
with skills the planet had never seen before.
Big cats.
(suspenseful music)
Every species of Sabretooth vanished.
Almost all the big cats survived.
Why them?
What's their story?
Which unique adaptations gave the big cats the edge
in this battle for survival?
We go back in time to when lions
were just beginning their ascent
to discover how they conquered the world
and how the tiger became
the real king of the jungle.
(suspenseful music)
1.8 million years ago,
there was a newcomer on the scene.
A predator with completely different tactics
to anything that had gone before.
A hunter that brought new abilities
to a competitive world.
The lion.
It's body was designed for power and acceleration
with huge muscles on his haunches.
The main competition for lions at the time
were the cat-like Sabretooths.
Their power was front loaded with massive neck muscles
to drive formidable canines into prey.
Megantereon was smaller than a male lion
but with those teeth,
was a dangerous adversary.
Homotherium was the same size as the lion.
Although it's serrated fangs were shorter,
it too was a force to be reckoned with.
These extinct animals are commonly called cats.
But they separated from the cats we know today
millions of years ago, and are actually quite different.
in the Pleistocene, all three species shared these plains
but lions outlived the others and went on
to dominate the globe.
For more clues as to what gave them the edge
in this world of deadly predators,
we can look at the behaviour of modern lions.
Lions are the most social of all cats.
(purring)
They can live in large prides of up to 35,
including adult males,
related females and their cubs.
(gentle music)
Close physical contact strengthens bonds
within the pride
and makes them smell the same.
Together, they can share the rearing of cubs,
kills and defence against predators.
(suspenseful music)
This teamwork was perhaps one ability
that helped lions survive alongside
their prehistoric rivals -
the social Homotherium and hyenas.
So how did the lion gain a competitive advantage?
Lions today are almost completely nocturnal
as they most probably were in the past.
And it's their night hunting
which perhaps holds the key to their survival
into the present day.
At dusk, lion prides head out onto the plains
led by the most experienced females.
With specialist filming techniques,
we can see what's going on after dark.
Infrared light and heat sensitive cameras
reveal rarely seen behaviour.
(suspenseful music)
These lions may look as if they're out for a stroll,
but they're hunting,
alert to every sound.
(suspenseful music)
Their knowledge of the terrain
and highly tuned senses will be key
in helping them pinpoint their prey.
They'll need to catch something bigger than a gazelle
to feed the whole pride.
Not this big.
When hippos are angry, they're very dangerous
and could easily kill a lion.
(suspenseful music)
Wildebeest are what they're after.
On dark nights, they huddle together for safety.
They don't make a sound.
The lions can't hear them
and they're too far away to see them.
But they can smell them.
(suspenseful music)
The pride spreads out and encircles the herd.
Two sisters team up.
(suspenseful music)
They're completely focussed and in sync.
(suspenseful music)
They separate and flank the wildebeest,
who are completely unaware of their presence.
Without infrared light or heat sensitive cameras,
this lioness's countershaded body
is extremely hard to see.
From where the wildebeest are sitting,
they have no chance of seeing her at all.
To humanise, only the stars would be visible.
Lion eyes are eight times more sensitive than our own.
This is dark.
The kind of hunting lions are designed for.
One lioness takes the wing.
The other silently moves right into the middle
of the herd.
During the day on open plains,
they'd never get this close.
(suspenseful music)
The winger gets the herd moving.
(suspenseful music)
The one in the centre bides her time.
From her low vantage point,
she can see the animals clearly against the sky.
Like most cats, lions have lots
of very fast twitch muscles for short,
sharp bursts of speed but are low on endurance.
Timing is critical.
(suspenseful music)
That was a close call for the wildebeest.
The lions will continue
for as long as it takes.
(roaring)
The matriarch lets the rest of the pride know
it's time to regroup.
(roaring)
This is how a big pride stays together in the dark.
The roar can be heard over eight kilometres away.
(suspenseful music)
They wait and smell the air.
(suspenseful music)
They've located another herd.
(suspenseful music)
Again, one lioness creates panic in the herd.
But they're completely unaware of her accomplice.
(suspenseful music)
She uses her strong canines and vice-like grip
to administer a suffocating bite
to the wildebeest's throat.
By killing her prey silently,
she's less likely to alert rival predators.
Although one lioness brought down this 200 kilo wildebeest,
it was a group effort.
During the Pleistocene,
team tactics would have been crucial
for defence against Sabretooths.
Lions would have certainly come into conflict
with the ferocious Megantereon.
This Sabretooth, with its long teeth,
could perhaps kill one lion,
but not a pride.
(suspenseful music)
(growling)
(suspenseful music)
Taking on a pack of Homotherium
would have been more of a challenge for lions.
However, analysis of Homotherium's eyes
and brain structure from fossil skulls
suggests they were daytime hunters.
Which is perhaps why lions chose the night
for most of their hunting.
(growling)
For lions today,
the night still offers no respite from another pack animal,
lion's ancient nemesis, the spotted hyena.
(hyenas growling)
They're aggravated.
The lions have invaded their patch
and chased the prey away.
When the male lions aren't around,
the hyena's, Africa's second largest carnivore,
intimidate the lionesses.
(hyenas laughing)
The adult females do their best
to keep the intruders at bay.
But there are enough hyenas here
to overpower them.
They'll kill cubs if they get the chance.
(suspenseful music)
In the Pleistocene, hyenas would have been
a serious threat to lions as they are now.
It could be that both species
needed to be social, just to deal
with each other.
(suspenseful music)
One of the males turns up.
(suspenseful music)
His brother provides back up.
Male lions won't hesitate to try and kill a hyena.
And the hyenas know it.
If it wasn't for teamwork,
the cubs might be dead.
The pride can now feed in peace.
Lions can eat as much as 30 kilos a night.
But even the king of the beasts
is willing to share his meal.
The pride is in high spirits.
(lions growling)
(gentle music)
(birds chirping)
With its social nature and the ability
to hunt at night, the lion was able
to find its own niche alongside prehistoric competitors.
Its first step in becoming the master of the plains
that we know today.
But even a pride can be overpowered.
(suspenseful music)
In times gone by, elephants would have lived in fear
of Homotherium and developed an enduring hatred
for large cat-like animals.
(jungle music)
(elephant roaring)
Once there was several species of elephants
roaming these plains, keeping the grasslands open.
There's just one species left.
A survivor of turbulent times.
In the crucible of evolution that was
the African plains of the past,
the lion's next test was about to begin.
There was another predator just emerging.
Like the lion, it would change
the history of the earth
and in the end, would challenge
all big cats for supremacy.
Homo erectus.
The first species of human to hunt large prey.
These early humans were implicated in wiping out
at least three species of elephant in Africa
and many other large mammals that were crucially
the prey of Homotherium.
In Africa, the age of the Sabretooths
was coming to an end.
Humans were replacing them.
Yet lions managed to live alongside
these early people.
Being wary and nocturnal
may well have helped them avoid conflict.
Around 1.7 million years ago,
early human hunters expanded their range
outside Africa into Southern Europe and Asia.
Almost a million years later,
lions finally followed them, crossing the Sahara
during a green spell.
Europe and Asia became the lion's new home from home
and soon they had spread from Spain
all the way to Japan.
Despite their neo-global domination,
there were large parts of South
and East Asia that were out of bounds for lions.
Lions may have ruled the plains,
but they were never the king of the jungle.
That crown belongs to another cat.
Weight for weight, it was as strong
and powerful as a lion.
While a pride could transit in the open,
this solitary cat preferred to stay in cover
in the forests and tall grasslands of Asia.
This was the tiger.
(gentle music)
In the depths of the ice ages,
the plains and frozen savannahs
were crowded with large mammals.
(horses exhaling)
Rhinos, mammoths, wizzant and auros,
potential prey of both lions and tigers,
all have defensive horns and tusks,
once used against Sabretooths,
were now needed against these two cats.
With the Sabretooths gone,
the lion and the tiger became Asia's top predators -
one perfectly adapted to the open plains,
and the other to forests and tall grasslands.
Today, tigers are still found in these places
but here, in the Russian far east,
prey is now scarce.
The huge herds have gone
as has the lion.
The tigers now have to wander vast distances
in search of a meal.
But when they see prey, they take no chances.
The tiger is a master of stealth.
Unlike the lion, it has more endurance muscle
which means it can last longer in a chase.
(suspenseful music)
And when tigers catch something, they eat all of it,
putting away a fifth of their body weight in 24 hours.
This ability to cope with feast and famine
is a trait that all can't share
and would have given tigers a competitive edge
in the prehistoric world.
Today, the Russian far east is at the edge
of their modern range, but it's thought
the tigers started life somewhere in China
and by 1.6 million years ago,
it had spread south into
a now submerged place called Sundaland
and on to the islands of Java and Sumatra.
It went as far west as Turkey
and to the far east, all the way to Baringa and Japan.
Asia was the tiger's heartland
and vast waves of it
were covered by tall grass savannah.
There is a place at the edge of the Himalayas
that closely resembles the tiger's prehistoric world.
This landscape, known as the Terai,
is home to the densest population of tigers
in the world.
It's a land of giants.
(gentle music)
(water splashing)
Herds of elephants still roam here,
the world's second largest rhino,
the world's largest buffalo
and heaviest wild cattle,
all equipped to defend themselves
against the largest living cat,
if they can see it before it sees them.
By looking at how modern tigers live here today,
we can discover more about how they've managed
to survive the Pleistocene.
And even though there are many here,
you wouldn't know it.
The highly secretive Bengal tiger
is perfectly camouflaged.
Out of 40 species of wild cat,
the tiger is the only one with stripes.
Perhaps a unique adaptation for living
in these tall grass lands.
(birds chirping)
Much of the wildlife here congregates around water -
a place to drink,
feed,
and cool down in the hot sun.
The one horned rhino's folded skin,
over four centimetres thick,
helps it to keep cool.
It may have also evolved as
a defence against Sabretooths.
The crocodile has thick skin too.
But instead, this cold blooded predator
basks on the banks to raise its body temperature.
Cheeky smooth coated otters
use their strength in numbers
to pester this deadly reptile.
Even the rhinos appear aggravated by the otters' antics.
(gentle music)
(birds chirping)
(monkeys screaming)
There's an air of nervousness
when the tall predator makes an appearance.
(suspenseful music)
Only a young bull elephant seems un-phased.
(suspenseful music)
Tigers also come here to drink and rest
in the heat of the day.
But they won't turn down the chance of a meal
if something comes their way.
An otter would make a tasty snack.
These are much too wary.
A mongoose shows less caution.
(suspenseful music)
Another tiger, possibly her sister,
is keen to share the meagre remains.
(tigers growling)
But there's clearly not enough for two of them.
(tiger growling)
She'll have to make her own kill.
Tall grasslands are hard places to live in.
With so many dangerous animals
and so little visibility, predator and prey
have to be constantly vigilant.
Tigers are able to travel around more easily
by using paths that have been created
by rhinos and elephants.
(gentle music)
From the air, you can see just how vast
these networks of trails are.
(birds squawking)
(suspenseful music)
Being surrounded by a wall of grass
makes navigation difficult.
But researchers tracking the movements
of tigers realise they must have a mental map
of their environment.
This adult female has a home range
of about 25 square kilometres.
She'll know every feature within it
and regularly scent marks trees and bushes
to let others know this is her domain.
(suspenseful music)
She's just one of the females
that live within this dominant male's territory.
The tigers in this part of the Terai
live in high densities
because of the abundance of prey.
The fading light of dusk
is a favourite time for tigers to hunt.
These hefty Gawa, once the prey of Sabretooths
are now on the tiger's menu.
At five times this male's weight,
it's hard to imagine how a tiger could take one on.
(suspenseful music)
But of all the cats, the tiger has
the strength and power to bring one down
with minimal struggle,
something a lion would find hard to do single handedly.
This tall grassland habitat isn't a place
a lion pride could live or hunt in either.
But like the lion, it's possible the tiger
became a night hunter to avoid competition
from prehistoric predators like Sabretooths
and early humans.
Hunting at night is now the tiger's specialty.
And with sophisticated night vision cameras,
we're able to capture rare images of tigers
that wouldn't normally be visible.
This young female, around 2 1/2 years old,
is on the cusp of becoming independent.
She's still living within in the safety
of her mother's territory and learning to perfect
the skills of a hunter.
She uses the well- worn animal trails
to move quickly and silently.
Rhinos can smell where she's been.
In the light of a full moon,
the biggest challenge is to avoid being spotted.
(deer barking)
The deer favour grazing in the open areas.
From our high vantage point,
we can easily see them.
But from eye level, even the thinnest grass
obscures almost everything.
Any glimpse of a tiger and the deer call.
(deer barking)
She knows she has no chance here.
(suspenseful music)
She stands her best chance on a starry night.
(deer barking)
Without the light of the moon,
she has the upper hand.
Now, only infrared and thermal cameras
allow us to see what happens.
(suspenseful music)
But the tiger will have to use all of her senses
to gauge where the deer are.
Relying on her hearing to track prey down
until she's close.
(suspenseful music)
Wherever the deer go,
the tiger follows.
(suspenseful music)
Crocodile infested rivers
are no barrier.
(suspenseful music)
In the pitch black, the tiger has scent, sound,
and her mental map to guide her.
(gentle music)
(birds chirping)
These deer know this is tiger country
and can never fully relax.
She can't see far in the long grass
so has to rely on her hearing,
the most acute of her senses.
(deer barking)
(birds chirping)
Her hearing is so sensitive
that she can pick up the faintest echo
of her own footsteps.
It's possible she uses this information
as a kind of echo location
to gauge the distance of the objects around her.
Her ears rotate to pick up the slightest sound.
It's crucial she stay silent too.
(grass crunching)
One wrong move
and her cover is blown.
(deer barking)
These rare images capture how the deer respond
to the tiger's presence,
barking warning calls loud and clear.
(deer barking)
(suspenseful music)
The tiger retreats into the long grass.
She's completely invisible now.
(gentle music)
And waits for the animals to settle down.
The tiger can hear some deer nearby.
(suspenseful music)
(animals screaming)
(deer barking)
(suspenseful music)
(deer barking)
This time, she won't go hungry.
(deer barking)
(gentle music)
Tigers survived a series of extinctions
during the Pleistocene that saw the demise
of the Sabretooths and many other large animals,
perhaps simply because they learned
to hide from early humans and hunted at night.
At the height of their power,
several hundreds of thousands of tigers
would have roamed across Asia.
(upbeat music)
But while the tiger was securing its place
in Eastern and Southern Asia,
lions were following the open plains northwards,
(upbeat music)
and cross the Bearing land bridge.
By 340,000 years ago, they were spreading
from North to South America.
(gentle music)
In the Americas, the lion came face-to-face
with some old enemies, Homotherium.
Although this Sabretooth had long gone
from Africa and Asia, it was still thriving here
and it lived alongside a monster Sabretooth,
Smilodon.
(lion growling)
Twice the size of its extinct ancestor, Megantereon,
and with even longer fangs,
perhaps competition with Smilodon
is why the American lion became
the biggest big cat ever,
weighting up to 400 kilos.
Incredibly, these three terrifying species
managed to co-exist for hundreds of thousands of years,
sharing the bounty of prey on offer.
(upbeat music)
Across the world, wherever the lion
was surrounded by other powerful predators,
it was its ability to hunt at night
and strong social bonds that were key
to its survival.
(upbeat music)
Now with the lion and tiger distributed
across the globe,
this really was the age of big cats.
(upbeat music)
But their reign would not last forever.
Around 60,000 years ago,
a new force emerged out of Africa
and swept the globe.
Homo sapiens.
By the time these cave paintings
of lions were made in Ice Age fronts,
modern humans were just establishing their supremacy
in the frozen north.
Whatever the primal thoughts behind
these striking images, fear or even reverence,
one thing seems certain:
the lives of these two social predators
have been interlinked for a very long time.
(upbeat music)
Today lions and tigers face an uncertain future
in this human dominated era.
(whistling)
During the golden age of big cats,
lions and tigers covered the globe.
But this age has long gone.
Now there are less than 20,000 lions
and fewer than 4,000 tigers.
The last remaining populations
are mainly confined to national parks and reserves.
If we want to share a future with big cats,
they need prey and space to roam.
(upbeat music)
Areas like the Masai Mara and Serengeti
are the lion's last strongholds.
These rich, green pastures, plump from
the seasonal rains,
have always attracted massive herds.
During the rainy season, it's a time of plenty.
A good start in life for the youngest members
of the pride.
They practice their hunting skills
on anything that moves.
(upbeat music)
Like all big cats, they'll need to rely
on every skill they possess
to survive in this changing world.
(upbeat music)