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This is Florida,

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a taste of the tropical,

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one of the world's most popular
holiday destinations.

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Here, mankind's unquenchable desire
to explore and colonise

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reaches astronomical proportions.

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And yet we are
relative newcomers here.

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While other creatures roamed
this part of North America

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for hundreds of millennia,

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we only arrived at the end of
the last great Ice Age,

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13,000 years ago.

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For most of its existence,

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North America remained
untouched by humans,

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its dramatic landscapes
and wildlife undisturbed.

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Then, sometime around 13,000 years ago,

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just as the ice started
to relax its grip,

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hunters from the north set foot
in Florida for the first time.

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Imagine if we could go back

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and join them as they explore
this unknown land,

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encountering strange animals not seen
before by human eyes.

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By piecing together the evidence
these creatures left behind,

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we can build a picture of this sub
tropical corner of the continent

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as it was 13,000 years ago.

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While most of North America was still
in the grip of the big freeze,

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Florida was an Ice Age oasis.

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Florida is aptly named
the Sunshine State.

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With an average of
8 hours of sun a day,

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it seems a world away from any ice age.

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Even 13,000 years ago,

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the massive ice sheets were hundreds of
miles away to the north.

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So what was it like back then?

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To investigate Florida's Ice Age past,

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one of the best places to look
is underground

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and underwater.

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Just below the surface lies
a very strange world.

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Millions of years of water action has
dissolved the limestone rock,

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forming a system of flooded caves
and tunnels.

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This vast underground network runs
for thousands of miles.

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Much of Florida is basically
a big rock honeycomb.

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In places the water is forced
to the surface, forming springs.

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Florida has one of the largest
concentrations of springs in the world.

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Filtered through sand and rock,

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the water is crystal clear.

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And welling up from deep
within the earth,

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it is a constant 22 degrees centigrade.

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This creates steaming oases,
and a profusion of life.

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Today these warm springs
are a refuge

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for one of Florida's
most tropical inhabitants.

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The West Indian manatee wasn't present
during the last Ice Age,

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but returned here
as the waters warmed up.

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Even now it is only found around this
sub tropical tip of the continent.

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But these springs aren't just a haven
for modern day wildlife.

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They've also yielded
many secrets of the distant past.

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When these pools were first explored,

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they would have looked like this:

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strewn with astonishing fossil remains
from Ice Age beasts.

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Florida has one of the richest
fossil records of the Ice Age

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anywhere on Earth.

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So what kind of creatures did
such bones and skulls belong to,

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and how did these springs
become their graveyards?

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Many of the fossils are from animals
that you can still see today.

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Indeed we'd recognise the vast
majority of Florida's Ice Age wildlife.

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Nevertheless, the most spectacular
Ice Age beasts did become extinct.

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And remarkably some of them share
a common ancestor with modern manatees.

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At first sight manatees might look
like seals or dolphins,

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but in fact some of their closest
relatives live on land.

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These toenails are the giveaway

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remarkably similar
to those of elephants.

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13,000 years ago,

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two other members of the elephant
family roamed this land.

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The manatees that swim
in Florida's springs today

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are living relatives of Ice Age
mammoths and mastodons.

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Some of the bones found
in these springs are easy to identify,

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but scattered in among them are
some more obscure remains.

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What kind of animal
could this belong to?

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These rosettes are bony scales,
or 'scutes',

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similar to those that cover
some reptiles today.

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But this is only one piece
of the jigsaw.

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Imagine what the creature
would have looked like

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when all these pieces were
fitted together.

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The scutes - around 2,000 of them

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once formed the shell of a huge animal
called a glyptodont.

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With its heavyweight exterior
the glyptodont looks like a reptile,

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like the alligator, which has been
around for millions of years,

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long before the last Ice Age.

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But the glyptodont wasn't a reptile.

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So what was it?

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There is a relative of the glyptodont
that's still alive today.

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It's the armadillo,

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and it's a mammal -

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the only mammal
with this kind of armour

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in the whole of North America.

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It may give us some idea

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of how an Ice Age glyptodont
might have looked when alive.

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Armadillos have poor eyesight,

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and rely mostly on
their sense of smell.

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Much of their time is spent nose to
the ground in search of food.

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Like the glyptodont, they're covered
in a layer of bony scutes.

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But the armadillo's body armour
is surprisingly thin and flexible

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and doesn't slow its owner down.

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So what about the glyptodont?

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The glyptodont's scute casing was up
to 5 centimetres thick,

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and fused into a solid shell.

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The shell alone was extremely heavy

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and the entire animal probably weighed
as much as a small car.

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It had extremely sturdy legs

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and five toes on each foot
to spread its massive weight.

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The heavy tail probably acted
as a counter balance.

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So the glyptodont
wasn't built for speed,

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but inside all this body armour,

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you'd imagine it was well protected.

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But one fossil skull tells
a different story.

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It suggests the glyptodont's defences
weren't impenetrable.

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These holes are the unmistakable
hallmark of a violent death.

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Their shape suggests that they
were made by the teeth of a big cat,

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but which one?

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Today there's only one large cat
in the region -

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the Florida panther.

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Though similar to the cougar of
the western states,

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it's now much rarer.

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But it was around during the Ice Age,

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so could it have killed the glyptodont?

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Although it could easily manage a deer,

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the Florida panther was probably
too small to tackle such a giant.

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But it wasn't the only big cat
around 13,000 years ago.

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There was also the
mighty American lion,

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powerful enough to kill a glyptodont.

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The scimitar-toothed cat,

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known to attack young mammoths,

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was also big and strong enough.

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And then there was
the most infamous cat of all -

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the sabre-tooth.

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Like the scimitar,

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it saved its awesome fangs
for slashing soft flesh.

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It would have been unlikely to risk
breaking them on bony armour.

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But the warm climate of Ice Age Florida

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made it a sanctuary
for another killer cat.

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Still South America's top predator,

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the jaguar is capable of taking prey
much larger than itself.

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Weight for weight,

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it's probably
the most powerful cat alive today.

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But most significant of all,

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the jaguar has a tell-tale trademark.

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Instead of going for the neck
or snout like most cats do,

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it kills with a crushing bite
through the skull into the brain.

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This makes the jaguar prime suspect
in this case.

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Even the glyptodont's defences
had a fatal flaw.

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13,000 years ago

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another, very different kind of hunter
reached this warm corner of the
continent.

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Florida's springs have produced an
unparalleled record
of these first people,

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examples of their craftsmanship
and hunting expertise,

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including razor sharp
flint spear points.

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The area was rich in flint
for making weapons,

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and in animals to hunt.

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And with the milder climate,

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these people probably had
an easier life

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than their contemporaries
further north.

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Small clues to their arrival have
survived undamaged over 13,000 years.

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Spear points, fishhooks and
other glimpses of their daily life,

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showing the versatility of these first
inhabitants of the sunshine state.

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They hunted a wide range
of Ice Age animals,

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and Florida possesses a unique
record of one such encounter.

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The skull of an extinct
bison, restored here,

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was discovered
in one of the rivers.

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Planted deep in the top of the skull
was a flint spear-point.

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But how did one man and a spear

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produce the huge force
behind this blow?

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The answer lies with small
bits of ivory, like this.

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They were once part of
an 'atlatal', or spear thrower.

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An atlatal acts as a sort of catapult,

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magnifying the strength of
a hunter's throw,

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allowing him to launch a spear
up to 200 metres

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with enough power to drive the point
through a bison's skull.

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It's this kind
of sophisticated technology

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that helped these early
North Americans to spread

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throughout
the entire continent.

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But what else did they find
once they reached Florida?

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Florida's Ice Age wildlife was
remarkably rich and diverse.

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There were many familiar animals
normally found further north,

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but also creatures unique
to the tropics.

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The result was a mixture of species
unlike anything we see today

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and an abundant food source
for the human immigrants.

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So what produced Ice Age
Florida's wealth of wildlife?

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Part of the answer comes
from the ice itself.

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At the peak of the last Ice Age,

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massive glaciers up to 2 miles thick

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covered over half
the North American continent.

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The ice destroyed the habitat
over which it lay,

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but it also had a profound impact
on regions far away.

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It created a domino effect
that rippled down the continent.

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The cold-climate conifer forests
of the north

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displaced broadleaved woodlands.

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Plants and animals were gradually
pushed south to find a warmer climate.

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Florida became a refuge from the cold.

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Down here is where the Ice Age north
met the sub-tropical south.

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Today in a cool, wooded part of
the sunshine state,

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you can still see some
of these northern refugees.

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The valleys along
the Apalachicola River

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are home to many species
that were forced here in the Ice Age

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and now remain far away from their main
populations further north.

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Like the copperhead snake

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and an astonishing
variety of amphibians.

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During the Ice Age,

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Florida was crucial to the survival of
many such mild weather species.

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They couldn't have withstood
the cold up north,

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and without this refuge they would
simply have become extinct.

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Another leftover,

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but one that arrived
from the opposite direction.

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This is the Virginia opossum,

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a tree dweller found throughout
many of the southern states.

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It's the only North
American marsupial -

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the young are born premature and
nurtured in the mother's pouch.

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And its only close relatives today

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are found in Central
and South America.

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The opossum is a rare survivor
from a South American invasion.

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In the Ice Age there were many other
species that had travelled north to
Florida

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including a giant.

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This spectacular claw is
40 centimetres long.

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And it belonged to a creature

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whose fossil remains
have been found throughout Florida.

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It's the claw
from a giant ground sloth.

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00:22:40,968 --> 00:22:43,270
And it really was a giant,

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6 metres long and
weighing up to 4 tons,

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it rivalled the mammoths in size.

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Although the giant ground sloth
is now extinct,

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like the opossum, it has family ties
in South America.

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The family resemblance is easy to see.

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These menacing claws are used
as grappling hooks,

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not weapons.

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They belong to the tree sloth,

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a peaceful vegetarian that spends
its time eating leaves.

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It seems a far cry from our vision
of an Ice Age beast.

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00:23:52,569 --> 00:23:56,306
It's likely giant ground sloths used
their claws in a similar way

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to hook branches and pull them
within reach.

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Like tree sloths,
they were vegetarians,

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and probably not fussy
about what they ate,

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chewing their way through leaves,
fruit, twigs and all.

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The big difference between the two
is their size.

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Giant ground sloths were 500 times
bigger than their modern relatives

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and standing upright
on their back legs,

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they towered as tall as a giraffe.

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00:24:50,625 --> 00:24:53,227
So far we have pieced together
something of the people

242
00:24:53,294 --> 00:24:55,865
who first explored the south east
of the continent,

243
00:24:55,932 --> 00:24:59,435
and the wildlife they must have
encountered and hunted.

244
00:25:02,838 --> 00:25:06,441
But what about the climate
and the landscape they all lived in?

245
00:25:10,645 --> 00:25:13,147
Florida is tropical today

246
00:25:13,714 --> 00:25:17,117
but how warm was it 13,000 years ago?

247
00:25:20,988 --> 00:25:24,192
This is Little Salt Spring
in central Florida,

248
00:25:25,260 --> 00:25:29,764
the source of one of the most unlikely
clues to the climate of the past.

249
00:25:41,041 --> 00:25:44,878
Brought up from a ledge more than
20 metres below the surface,

250
00:25:45,011 --> 00:25:47,947
was the fossilised shell of
a tortoise,

251
00:25:48,047 --> 00:25:51,350
a giant tortoise, much like this one.

252
00:25:59,760 --> 00:26:02,329
Giant tortoises are now
only found basking

253
00:26:02,462 --> 00:26:05,498
in the heat of a few islands
along the equator.

254
00:26:10,803 --> 00:26:15,674
They can grow more than 2 metres long
and weigh as much as 3 men.

255
00:26:21,047 --> 00:26:26,452
But the giant tortoises of Ice Age
North America were even larger.

256
00:26:34,759 --> 00:26:36,928
Florida does have tortoises today,

257
00:26:37,028 --> 00:26:39,197
but on a much smaller scale.

258
00:26:40,932 --> 00:26:42,667
This is the gopher tortoise.

259
00:26:45,269 --> 00:26:47,404
Tortoises are cold-blooded animals -

260
00:26:47,538 --> 00:26:51,310
they rely on external temperature
to keep themselves warm.

261
00:26:51,643 --> 00:26:55,013
Although Florida is plenty warm
enough for much of the year,

262
00:26:55,113 --> 00:26:58,516
during the winter months it
can get cold.

263
00:27:06,957 --> 00:27:08,792
So to survive the winter

264
00:27:08,892 --> 00:27:13,162
gopher tortoises must burrow
and hibernate underground.

265
00:27:22,273 --> 00:27:26,643
The colder it gets, the deeper
into their burrow they go.

266
00:27:33,883 --> 00:27:36,419
Giant tortoises, however, can't burrow

267
00:27:36,519 --> 00:27:38,520
and they sleep above ground.

268
00:27:38,754 --> 00:27:42,224
They need relatively warm temperatures
all year round.

269
00:27:42,591 --> 00:27:45,126
The fact they were in Florida during
the Ice Age

270
00:27:45,193 --> 00:27:48,998
means that, paradoxically, the climate
must have been more stable

271
00:27:49,065 --> 00:27:51,534
and even milder than it is today.

272
00:27:53,869 --> 00:27:55,805
So we know something of the climate,

273
00:27:57,373 --> 00:28:00,575
but what about the vegetation
and the landscape?

274
00:28:00,942 --> 00:28:04,079
How did that look 13,000 years ago?

275
00:28:07,982 --> 00:28:11,285
Today Florida is one of the wettest
parts of the continent,

276
00:28:11,418 --> 00:28:16,325
especially the vast swampy area
known as the everglades.

277
00:28:21,296 --> 00:28:25,466
Flooded grassland stretches
as far as the eye can see.

278
00:28:27,235 --> 00:28:28,936
But despite their name,

279
00:28:29,036 --> 00:28:33,173
the mighty everglades did not exist
during the Ice Age.

280
00:28:34,141 --> 00:28:37,210
So what did prehistoric Florida
look like?

281
00:28:41,147 --> 00:28:43,382
There's one place in Northern Florida

282
00:28:43,482 --> 00:28:47,888
that has revealed more Ice Age secrets
than almost anywhere else -

283
00:28:51,158 --> 00:28:55,495
the dark, slow moving waters
of the Aucilla River.

284
00:29:01,767 --> 00:29:04,703
Here, ideal conditions
for fossilisation

285
00:29:04,837 --> 00:29:08,106
created a hidden store of
Ice Age evidence.

286
00:29:14,414 --> 00:29:17,483
Unlike in the crystal
clear spring waters,

287
00:29:17,584 --> 00:29:20,920
these clues were never on view
for all to see.

288
00:29:21,821 --> 00:29:24,189
But the Aucilla has now
been studied intensively

289
00:29:24,256 --> 00:29:26,125
for more than 20 years.

290
00:29:33,131 --> 00:29:38,369
Along some stretches of the riverbed
were massive bones, recreated here,

291
00:29:38,636 --> 00:29:42,775
perfectly preserved
for more than 13,000 years.

292
00:30:08,331 --> 00:30:10,668
One of the most significant discoveries

293
00:30:10,768 --> 00:30:14,038
was the huge skull
of an American mastodon.

294
00:30:20,544 --> 00:30:23,513
Mastodons, close relatives of mammoths,

295
00:30:23,647 --> 00:30:27,717
were widespread all over
North America during the Ice Age.

296
00:30:28,017 --> 00:30:30,152
They grew over 3 metres tall -

297
00:30:30,252 --> 00:30:33,022
the size of African elephants today.

298
00:30:37,459 --> 00:30:39,429
We know a lot about the mastodons,

299
00:30:39,529 --> 00:30:41,031
especially their diet,

300
00:30:41,131 --> 00:30:44,300
thanks to the preserved dung
they left behind.

301
00:30:48,237 --> 00:30:53,208
Some of this Ice Age dung was found
beneath the skull in the Aucilla.

302
00:31:00,648 --> 00:31:02,984
The dung contained plant remains

303
00:31:03,117 --> 00:31:05,519
that tell us what the mastodon
was browsing on

304
00:31:05,653 --> 00:31:08,457
13,000 years ago
or more.

305
00:31:16,698 --> 00:31:19,567
A mixture of trees and grasses.

306
00:31:28,575 --> 00:31:32,946
This suggests that Ice Age Florida
was drier than it is today

307
00:31:33,046 --> 00:31:37,218
a mix of woodlands and savannah,
rather than swamps.

308
00:31:44,992 --> 00:31:49,796
And mastodon teeth found in the Aucilla
held a more important revelation.

309
00:31:50,063 --> 00:31:53,700
The enamel contains chemical
signatures of the local soil,

310
00:31:53,833 --> 00:31:56,602
passed via the plants
the mastodons ate.

311
00:31:57,536 --> 00:32:00,105
But some of the chemicals found
in the Aucilla teeth

312
00:32:00,239 --> 00:32:04,645
could only have come from soils
hundreds of miles further north.

313
00:32:05,412 --> 00:32:09,649
The inescapable conclusion is
that these mastodons migrated

314
00:32:09,749 --> 00:32:13,720
making a round trip of more
than 400 miles every year.

315
00:32:14,921 --> 00:32:20,225
And since their dung also contains remains
of summer fruits from the Aucilla region,

316
00:32:20,325 --> 00:32:23,428
they must have travelled north
for the winter.

317
00:32:27,799 --> 00:32:29,867
The question is why?

318
00:32:30,301 --> 00:32:32,536
Why leave a place,
which, as we have seen,

319
00:32:32,603 --> 00:32:36,408
was abundant with food,
and a refuge from the cold?

320
00:32:36,542 --> 00:32:38,577
And why go north for the winter,

321
00:32:38,677 --> 00:32:41,546
when most migrants move south?

322
00:32:44,783 --> 00:32:47,985
Perhaps the present climate can
provide a clue.

323
00:32:53,791 --> 00:32:56,793
Florida has a peculiar seasonal quirk.

324
00:32:59,329 --> 00:33:01,533
Although the winter months are cooler,

325
00:33:01,633 --> 00:33:05,069
they are also drier - much drier.

326
00:33:08,472 --> 00:33:13,243
Between October and February
there's almost no rainfall at all.

327
00:33:21,417 --> 00:33:23,853
Could it be that drastic water shortage

328
00:33:23,920 --> 00:33:27,089
was the reason
for the mastodons' epic migrations?

329
00:33:31,562 --> 00:33:36,032
Another big piece of this puzzle
lies far out to sea.

330
00:33:56,884 --> 00:33:58,719
This is the ocean floor,

331
00:34:02,058 --> 00:34:04,960
but this isn't rock
sprouting out of the bottom,

332
00:34:05,694 --> 00:34:06,728
it's wood.

333
00:34:09,831 --> 00:34:13,101
It's the remains of
prehistoric tree stumps,

334
00:34:13,234 --> 00:34:16,704
some dated at more
than 12,000 years old.

335
00:34:28,483 --> 00:34:32,053
This sunken forest is
unmistakable evidence

336
00:34:32,153 --> 00:34:36,290
that what is now seabed
was once dry ground.

337
00:34:41,962 --> 00:34:44,464
And what is now Florida's coastline

338
00:34:44,564 --> 00:34:47,500
was once many miles inland.

339
00:34:48,668 --> 00:34:49,802
But why?

340
00:34:52,605 --> 00:34:53,873
To answer that

341
00:34:54,106 --> 00:34:56,844
we have to go back
to the mighty Ice Age glaciers

342
00:34:56,911 --> 00:34:59,480
that covered almost half the continent.

343
00:35:11,057 --> 00:35:15,094
These glaciers contained
immeasurable amounts of ice.

344
00:35:26,306 --> 00:35:28,841
So much water was locked up
in this ice

345
00:35:28,941 --> 00:35:32,544
that it lowered sea levels
by over 70 metres.

346
00:35:33,379 --> 00:35:35,414
The south east coastal
shelf was exposed

347
00:35:35,547 --> 00:35:38,550
and Florida doubled in size.

348
00:35:40,318 --> 00:35:43,121
The Everglades were dry land.

349
00:35:49,893 --> 00:35:52,529
This triggered other dramatic changes.

350
00:35:52,662 --> 00:35:54,066
As sea levels dropped,

351
00:35:54,166 --> 00:35:56,668
so did the inland water tables.

352
00:35:57,002 --> 00:36:01,606
Florida's fresh water drained away
through the porous limestone rock.

353
00:36:04,642 --> 00:36:07,444
Pools dried up and springs diminished.

354
00:36:07,611 --> 00:36:09,680
Florida was on the brink of drought,

355
00:36:09,780 --> 00:36:13,149
and animals would have had to travel
to find food and water.

356
00:36:13,383 --> 00:36:17,854
So each year mastodons would have
migrated to the wetter regions.

357
00:36:21,859 --> 00:36:23,894
But in a few key places,

358
00:36:23,961 --> 00:36:27,531
water was still pushed up
from underground as a spring -

359
00:36:29,800 --> 00:36:33,436
a vital oasis where
wildlife would have converged

360
00:36:33,503 --> 00:36:35,371
from many miles around.

361
00:36:40,709 --> 00:36:43,779
Many animals would have fed
on the surrounding vegetation

362
00:36:43,912 --> 00:36:46,214
and others come here to drink.

363
00:36:50,051 --> 00:36:53,790
And predators would have lain
in ambush for the unwary.

364
00:36:54,290 --> 00:36:56,192
It's no wonder
that so many fossil bones

365
00:36:56,259 --> 00:36:59,128
have been found on the bottom
of these springs -

366
00:36:59,295 --> 00:37:03,932
clues that can open up a window
on the Ice Age past.

367
00:37:12,973 --> 00:37:15,075
Bringing this evidence together,

368
00:37:15,542 --> 00:37:19,715
we can create a living picture
of this region as it was then.

369
00:37:20,716 --> 00:37:23,952
We can now go back 13,000 years

370
00:37:24,085 --> 00:37:29,190
and see what a day around one of
Florida's springs might have been like.

371
00:37:38,298 --> 00:37:42,502
Dawn on the southeast tip
of Ice Age North America...

372
00:37:44,637 --> 00:37:49,310
On the banks of a spring-fed pool,
the early grazers stir.

373
00:37:57,784 --> 00:38:00,954
Today there is a group of
larger visitors here too.

374
00:38:11,229 --> 00:38:14,099
A herd of mastodons,
led by the matriarch,

375
00:38:14,199 --> 00:38:16,703
have just returned
from their annual migration,

376
00:38:16,803 --> 00:38:19,105
hundreds of miles to the north.

377
00:38:26,912 --> 00:38:29,147
Now the winter drought is over

378
00:38:29,248 --> 00:38:32,651
and the spring water has been
topped up by recent rains.

379
00:38:50,769 --> 00:38:53,872
Another group has also set up
camp nearby.

380
00:38:54,138 --> 00:38:57,308
Hunters, descendants
of the first human settlers

381
00:38:57,441 --> 00:39:00,044
that entered the continent
in the far north.

382
00:39:02,179 --> 00:39:05,382
Compared to the harsh conditions
their ancestors faced,

383
00:39:05,515 --> 00:39:07,584
this place is paradise.

384
00:39:10,753 --> 00:39:13,558
Targets for the hunters' spears
are plentiful.

385
00:39:20,831 --> 00:39:22,332
Around the spring,

386
00:39:22,399 --> 00:39:26,303
lush vegetation attracts
the giant ground sloth, too.

387
00:39:27,937 --> 00:39:30,907
Both mastodons and sloths
are browsers,

388
00:39:31,040 --> 00:39:33,376
but the mastodons roam
far and wide

389
00:39:33,442 --> 00:39:35,778
to find the kind of plants
they need.

390
00:39:36,311 --> 00:39:39,081
The giant ground sloth isn't built
to travel far,

391
00:39:39,214 --> 00:39:43,420
but it makes up for that by having
the reach of a giraffe.

392
00:40:01,569 --> 00:40:05,072
Its huge claws may also be used
for self-defence,

393
00:40:05,173 --> 00:40:07,375
although even the
most powerful predator

394
00:40:07,475 --> 00:40:11,213
would think twice before tackling
so large a prey.

395
00:40:19,754 --> 00:40:24,425
In any case, this female jaguar is
little threat right now.

396
00:40:25,092 --> 00:40:27,061
Once she's quenched her thirst

397
00:40:27,161 --> 00:40:30,931
she'll find a shady place
to doze in the heat of the day.

398
00:40:41,009 --> 00:40:44,111
Meanwhile the ground sloth,
like the mastodons,

399
00:40:44,178 --> 00:40:48,182
must eat most of the day to
fuel its huge bulk.

400
00:40:56,222 --> 00:40:57,924
This may be the Ice Age,

401
00:40:58,324 --> 00:41:00,960
but by midday temperatures soar

402
00:41:01,060 --> 00:41:04,363
drawing another predator
to the spring to drink -

403
00:41:05,297 --> 00:41:08,168
the notorious sabre-toothed cat.

404
00:41:19,612 --> 00:41:23,015
Most creatures give the sabre-tooth
a wide berth,

405
00:41:23,248 --> 00:41:26,218
but this skunk seems unconcerned.

406
00:41:40,799 --> 00:41:44,102
The sabre-tooth may be the ultimate
Ice Age predator

407
00:41:44,202 --> 00:41:46,171
but the skunk is feared, too

408
00:41:46,271 --> 00:41:49,240
because of its unique system
of self-defence.

409
00:41:53,144 --> 00:41:56,347
These stripes serve to warn off
most attackers,

410
00:41:56,513 --> 00:42:01,318
but perhaps the sabre-tooth has yet
to learn exactly what they mean.

411
00:42:22,472 --> 00:42:25,942
Stamping his feet, the skunk issues
a final warning,

412
00:42:26,008 --> 00:42:28,844
but this big cat is still curious

413
00:42:29,245 --> 00:42:31,914
and now the skunk
has had enough.

414
00:42:38,255 --> 00:42:39,356
The dreaded sabre-tooth,

415
00:42:39,456 --> 00:42:42,225
killer of mastodons
and other Ice Age giants,

416
00:42:42,325 --> 00:42:46,495
is defeated by a small
but very smelly skunk.

417
00:42:58,873 --> 00:43:00,174
In the heat of the day,

418
00:43:00,274 --> 00:43:03,846
hunters can afford to slow down
and rest in the shade.

419
00:43:03,946 --> 00:43:07,182
It's one of the advantages
of a high protein diet.

420
00:43:28,301 --> 00:43:31,473
Llamas originated here
in North America

421
00:43:31,573 --> 00:43:33,975
and are regular visitors
to the spring.

422
00:43:37,678 --> 00:43:40,381
The strange looking tapir
is common too.

423
00:43:40,681 --> 00:43:44,084
And there's another animal
that is even more bizarre -

424
00:43:45,585 --> 00:43:47,187
a glyptodont.

425
00:44:07,941 --> 00:44:11,811
This lumbering vegetarian
is no threat to the llamas,

426
00:44:11,911 --> 00:44:14,513
but it does arouse their curiosity.

427
00:44:24,422 --> 00:44:27,792
The glyptodont is short-sighted
and wary,

428
00:44:27,825 --> 00:44:30,296
but it has little to fear from llamas.

429
00:44:39,838 --> 00:44:44,509
They're easily warned off
and soon head back towards the spring.

430
00:44:57,589 --> 00:45:01,693
But as the day cools down,
another scent is in the air

431
00:45:01,793 --> 00:45:05,630
alerting the tapir's
ultra-sensitive nose to danger.

432
00:45:16,339 --> 00:45:18,741
The llamas pick up the signals too.

433
00:45:24,813 --> 00:45:28,419
It's the jaguar, back on the prowl.

434
00:45:34,257 --> 00:45:35,558
Though very powerful,

435
00:45:35,692 --> 00:45:37,226
she's not a sprinter

436
00:45:37,327 --> 00:45:40,896
and she needs to get close
to her prey before she strikes.

437
00:46:16,997 --> 00:46:18,899
This time she's run too soon

438
00:46:18,999 --> 00:46:21,101
and it's a fruitless chase.

439
00:46:30,044 --> 00:46:32,180
Then her attention is diverted

440
00:46:32,513 --> 00:46:34,715
to a slower-moving target.

441
00:46:41,888 --> 00:46:45,158
Slow but not defenceless,

442
00:46:46,426 --> 00:46:49,328
she backs off and tries
a different approach.

443
00:46:58,805 --> 00:47:01,207
There's obviously a meal in there,

444
00:47:01,308 --> 00:47:02,842
but how to get to it?

445
00:47:12,351 --> 00:47:14,152
She homes in on the head

446
00:47:15,220 --> 00:47:17,422
and bites straight
through the skull.

447
00:47:29,368 --> 00:47:31,270
The glyptodont is dead,

448
00:47:31,637 --> 00:47:34,206
but the jaguar still goes hungry.

449
00:47:35,040 --> 00:47:38,276
Unable to crack
her victim's tough armour,

450
00:47:38,443 --> 00:47:42,713
all she manages to walk away
with is a bony scute.

451
00:47:43,214 --> 00:47:46,016
The jaguar will vanish
from North America,

452
00:47:47,251 --> 00:47:50,689
and glyptodonts,
like many Ice Age beasts,

453
00:47:50,822 --> 00:47:52,224
become extinct.

454
00:47:53,892 --> 00:47:55,393
But at the bottom of a spring,

455
00:47:55,460 --> 00:47:58,496
one tiny fragment
of an Ice Age giant

456
00:47:58,563 --> 00:48:02,867
will remain undisturbed
for 13,000 years,

457
00:48:03,000 --> 00:48:09,239
while above it the landscape of Florida
will change forever.

458
00:48:09,920 --> 00:48:13,420
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