(suspenseful music)
Forget tigers.
Forget lions, and leopards.
One ferocious feline killed its prey with canines
nearly a foot long.
(tiger growling)
But while the beast weighed close to half a ton,
walked on paws three times larger than a Bengal tiger's,
Smilodon remains one of the most enigmatic predators,
past or present.
(tiger growling)
Now, scientists on different continents
are breaking in to Smilodon's secret life
through those incredible fangs.
So there's lot of advantages of having these
elongated sabers, one of which is the ability
to have your prey bleed out very quickly.
Dr. Larisa DeSantis is a vertebrate
paleontologist at Vanderbilt University.
The saber teeth are actually as long, if not longer,
than some T-Rex teeth.
Dr. Nicolas Chimento is at the
Comparative Anatomy Lab of Vertebrate Evolution
in the Natural History Museum, Buenos Aires.
(speaking in foreign language)
This is original material
from a saber tooth cat, a Smilodon populator.
It was found here in (foreign language)
in the Pampas region.
His new discovery in Argentina
suggests that knife-tooth used its canines
not just to dispatch prey, but to battle with members
of its own kind.
(Nicolas speaking foreign language)
The study that we conducted
was based on two skulls that had a perforation in this area.
And when we began to analyze the fang,
and then introduced it into the hole,
it fit perfectly.
The damaged skulls weren't found together,
but both have similar holes at the top of the nasal area,
between the eyes.
Nicolas quickly ruled out natural decay and disease
as possible causes of the wounds.
His team concluded that the injuries could have
only been inflicted by another large animal.
A swift kick from a hoofed mammal would leave
a very different type of injury.
Bear or dire wolf fangs would've left
much smaller punctures.
(Nicolas speaking foreign language)
Here it had an oval shaped hole,
and the shape coincided with the canine
of a saber tooth cat.
So what we did was insert the canine into that hole
and it matched the shape and fit perfectly inside the skull.
The punctures in both skulls
could only have been inflicted by other Smilodons.
So this is a wound that would have
undoubtedly caused the animal to die.
The Argentine specimen shows a wound
that appears to be instantly fatal.
It's a huge discovery, as Smilodon fossils
are relatively rare in South America.
The lethal injuries may be from male cats
fighting for mates, or defending territory.
But no one has been able to confirm the sex
of any Smilodon fossil.
Unlike many mammals, males and females
were about the same size.
They don't display a large degree of sexual dimorphism,
which is that the males are fundamentally larger
than the females.
So it is pretty hard to tell apart males and females
and really not possible in these extinct saber tooth cats.
Dr. DeSantis unpacks saber tooth behavior
by examining minute details on and in their teeth.
Larissa works on Smilodon fatalis,
which roamed North America, and chased its prey
into the sticky La Brea Tar Pits.
Smilodon was the only creature during the Pleistocene
with foot long fangs.
Despite their fierce nature and lethal weaponry,
her research at La Brea reveals surprising details
about the importance of saber fangs.
Smilodon kittens didn't sport true fangs
until they were about three years old.
There is a true evolutionary benefit to having that tooth
come completely in before the other tooth,
the baby tooth, falls out.
And that provides evidence that these animals
were potentially provisioned or cared for
because those teeth were so critical to their survival.
The cat's impressive cuspids slowly grew
while the baby teeth were still present,
adding protection to the developing fangs.
And what's really neat is that there's actually
this sort of little groove on the inside
of that deciduous tooth where the adult tooth
will start to actually come in as well.
The saber teeth would actually grow in
alongside that baby tooth until it was erupted,
at which point then they had their adult saber.
But then, those fangs grew twice as quickly
as those of modern day lions.
That's twice as fast as human fingernails,
about a quarter inch per month.
Until their weaponry was fully developed, Smilodon kittens
needed to stick close to mom.
It was taking a long time for these teeth to develop,
and those were that critical for hunting,
then there may have been an extended period
of parental care, allowing for these animals
to become more mature and able to hunt effectively
on the landscape.
This suggests that the prehistoric cats
may have had expanded family structures similar to wolves.
There has to be some level of care
for the young individuals that's compensating for the fact
that it's gonna take a long time
for these sabers to develop.
We're not sure if saber toothed cats
hunted in pairs or in prides, but they worked together.
We think that they were at least hunting
in some sort of multiple cat scenario
because of the high abundance of saber tooth cats
found at La Brea.
On hot Pleistocene days, only an inch or two
of sticky tar would've trapped animals forever.
So if you have leaf matter covering these tar seeps
or if it looks like it's a watering hole
and you sort of step in, all it requires is stepping in
a few inches even to begin to get stuck
and unable to move yourself out.
Smilodon preferred to ambush its prey,
force it into submission, and then bite down.
(suspenseful music)
(animals squealing)
(Nicolas speaking foreign language)
In general, a saber tooth's back limbs
were a bit shorter and more robust.
And the front limbs were a little longer.
They prefer to hunt using short bursts.
The saber tooth cats were taking down prey
from more forced eco-systems, eating things like
tapirs or maybe some camels or deer.
The prehistoric landscape was rich
with forests and prairies, with many big beasts.
Giant ground sloths, short faced bears,
mammoths and mastodons, and camel-like creatures
lived side-by-side with Smilodon.
Saber toothed cats were the apex predators
throughout Pleistocene America.
First appearing two and a half million years ago,
then vanishing just 8,000 years ago.
(speaking foreign language)
There was a large variety of prey,
and saber tooth cats would choose the largest and heaviest.
It could consume a young mastodon, so a 1,000,
1,500 kilo animal might've been hunted by a Smilodon.
Despite their dental arsenal,
Larissa's research also reveals insights
about the complex social lives of saber toothed cats.
Smilodon fossils from La Brea show injuries, too,
and something else.
So specimens that have arthritis or have had an abscess
to their tooth, or who have had a broken canine,
for example, these broken sabers, and one of the things
that's often found is that there's evidence
that they've healed from these injuries.
They've lived for some prolonged period of time.
Not all of the saber toothed cats
died in the tar.
Many lived to ripe old ages, despite serious injuries
from panicked prey or other cats.
With all of these different injuries,
we started to wonder, were these animals
doing something different?
If you were kicked in the jaw, or you had an abscess,
were you relegated to the outside of the pack
or relegated to hunting by yourself?
Were you desperate, were you chewing on carcasses
and just sort of eating the scraps of what you could find?
Larissa DeSantis can tell exactly
what an extinct creature ate throughout its lifetime.
(scraping tooth) You are what you eat.
Everything you eat is incorporated into your tissues
with a different sort of fractionation factor.
Whether you eat lots of fish or if you eat lots of meat,
all of that is incorporated to your hair, your fingernails,
your bones, your teeth.
And what's great about teeth is it locks in that signature
and preserves it over thousands to millions of years.
So we can actually analyze the teeth of fossil animals
and get an understanding of what they were eating.
By analyzing the chemical signature
of a Smilodon's tooth enamel, she can see what it preyed on
and where that prey lived.
And by studying the microscopic grooves and wear
on the surface of the teeth, she can tell whether the owner
crunched bone or dined on delicacies.
And what we actually found was pretty interesting
is that the individuals that were injured
were actually eating softer foods, and this suggests
that potentially they were actually being provisioned food.
So these weren't animals that were just desperately
scavenging for whatever food they could find,
they were actually able to get access to the flesh, likely,
potentially by other cats.
And so that was really, really an exciting find.
I mean that is quite remarkable,
because that suggests that these animals were really,
you know, caring for each other.
So this is the hole where a canine would fit.
But this shows where it lost its canine
and the bone grew in, in this area.
And so this animal lived for some prolonged period of time
with the loss of its canine.
This behavior is seen in African lions today.
Rare footage from Tanzania shows an able-bodied lioness
ensuring that a senior cat with a broken jaw
has access to palatable food.
While the discovery in Argentina reveals that Smilodon
may have been even more ruthless than previously thought,
these great saber cats clearly developed strategies
that ensured their survival.
Smilodon disappeared frustratingly close to us in time,
going extinct around the end of the last glacial period
when humans were relatively new to the Americas.
Did they meet their match in us?
(speaking foreign language)
The majority of herbivores had adapted
to live in wide open spaces,
and the giant grasslands of South America.
As it got hotter, environments like forests and jungles
developed faster, which means that the number
of giant herbivores began to decline.
And, in the last ice age, many were also
being hunted by humans.
A combination of these two factors, we're talking about
climate change that altered eco-systems, plus human beings,
delivered the fatal blow to many species.
The other great thing about La Brea is that we're finding
these fossils from about 50,000 years ago til the present.
And so they have different ages and different dates.
And so we can begin to actually tease apart the cause
of this extinction, the effects of climate change,
and human arrival on the impacts on these animals
and why they may have gone extinct.
Saber toothed cats were incredibly successful
for a very long time, and some scientists believe
that we're just in a lull between Smilodon
and the emergence of a new species.
Today, we only see one single feline species
alive that has a similar skull morphology
like that of the saber tooth cat.
The clouded leopard is a mid-sized cat
that prowls the tropical forests of Indonesia
with very elongated canine teeth.
If they're able to more effectively hunt
by having elongated canines, then that could get
sort of fixed in that population and you could see
these elongated canines yet again.
Long killing fangs evolved so many times
during the past twenty million years
that there's every reason to believe
that a new saber toothed cat just might roam Earth again.
(intense music)
(tiger growling)