Nature's Strangest Mysteries: Solved (2019–…): Season 1, Episode 18 - Rattleless Rattlesnake - full transcript

Narrator: Why does this elephant
look like it's smoking?

This behavior is
completely unique.

Narrator:
How is the brazilian rainforest

Suddenly submerged?

Why are fish swimming
through the trees?

Narrator:
And what has happened

To this snake's
most defining feature?

Nelson: It's a rattlesnake
without a rattle.

I don't know if that's even
a rattlesnake anymore.

Narrator:
Nature is awe-inspiring,

But sometimes it just
doesn't make sense.



Man: I have never seen
anything like this.

Our team of experts investigates
the weirdest animal behavior...

That's amazing.

...And the most unexpected
events...

What is causing that?

...Ever caught on camera.

My god!

These are...

Captions paid for by
discovery communications

Jardim, brazil, February 2018.

Overnight, a forest footpath
in an ecopark

Takes on a slightly surreal
and soggy look.

What you're looking at is not
a crystal-clear aquarium,

So why are fish
swimming through the trees?



Riskin:
So, this is a weird one.

It looks like some kind
of alien world

Where everybody lives
underwater,

But there are walkways,
but it's not.

This is nature,
so why is it like that?

Narrator: The question is, where
did all this water come from

And why is is
so perfectly crystal clear?

Clues may lie on
the other side of the globe.

Every year, green lake
in austria

Is transformed
into a scuba divers' playground.

The park's trees and benches
are totally submerged.

So, green lake floods every
spring and summer

When the glaciers melt,

So it's that clean, clear runoff
from glacial melt,

And the streams and the rivers
all adding to green lake,

Which is why it's so clear.

Narrator: Could the flooded
ecopark in brazil

Be the result
of something similar?

This is like that,
but it can't be the same thing

Because green lake is water
that comes from a glacier.

It's fresh, clear water
with nothing in it

Because it comes from snow.

Narrator: The jardim area
doesn't get any snow.

The ecopark is in a rainforest
and it gets really hot here

In February...
Up to 85 degrees fahrenheit.

If this water is not from snow,
could it be from a recent flood?

Riskin:
Maybe the river swelled up.

It's a big flood and now
everything's underwater.

Narrator: Flooding does happen
in other parts of brazil.

Nearly 100,000 square miles
of amazon rainforest

Are submerged every year as the
famous river spills its banks

And rises by 30 feet.

Yellow-spotted river turtles
swim through the trees,

While caiman become
temporary forest dwellers,

And arboreal animals
like sloth have to swim

Rather than climb
through the branches.

So, is something similar
happening in jardim?

This isn't part of the amazon.

This is south of that, so that
shouldn't be happening here.

Narrator: The amazon is over
1,000 miles north of jardim,

But the source of the amazon's
floods may still hold clues

To what's happening here.

Riskin:
Another possibility

Is that there's just been
a lot of rain.

Narrator: Well, in early 2018,

The area was indeed hit
by a deluge of heavy rain.

Increased rainfall could cause
flooding in the area.

Narrator: But normally, heavy
rain transforms a river

Into a murky mess,

The opposite of the
crystal-clear water of jardim.

In reality, it can't just be

The run-of-the-mill
flash flooding

Because very quick flooding

Really always brings in
a lot of sediment.

You would really expect
the water

To be much more cloudy
and murky and full of debris,

But that was definitely
not the case here.

Riskin: It's almost like this
water's been filtered.

There's something else going on.

The region is made up of bedrock

That is comprised
of porous limestone,

And that filters mud and sand
and silt beautifully.

Narrator: Usually, the water
comes up through springs

That supply the famously
transparent rio de prada,

Which makes this river

And its amazingly transparent
tributaries

A snorkeler's paradise.

But heavy rains
overloaded the system.

All the extra water
filtered down

Through the limestone bedrock,
supercharging the springs,

And causing the river level
to rise from below.

The result...
A crystal-clear filtered flood.

But there's one more thing.

So, the underlying bedrock of
the area acts as a water filter,

Making the water the nice clear
that we see,

And on top of that,
the limestone particles

In the water
actually refract the light

And make it
this nice blue color.

Narrator: But the phenomenon
is short-lived.

Within a day or two,

This submerged dream world
disappears,

Taking the fish with it
as the flooding subsides

And the water
flows back down the river.

It's incredibly rare
for this to happen.

The rainforest only gets
transformed

About once every four years,

Turning a walk in the park
into a swim.

♪

Isla santa catalina,
sea of cortez.

A scientific expedition

Stumbles upon a strange
species of rattlesnake.

It's a rattlesnake
without a rattle.

I don't know if that's even
a rattlesnake anymore.

Riskin: So, here's a mystery...
You've got a snake

That looks like a rattlesnake.

It's got the head
of a rattlesnake,

It's got the body
of a rattlesnake,

It even shakes its tail
like a rattlesnake,

But there's no rattle.

So what's going on?

Narrator: Animal planet host

And wildlife biologist
forrest galante is also curious.

All other living species
of rattlesnake

Have an active rattle.

That's why they're called
rattlesnakes.

But this one doesn't.

Why?

Narrator: With no rattle,
how do we even know

The santa catalina rattler
is a rattlesnake to begin with?

Well, aside from a rattle,

Rattlers have a triangle-shaped
head and vertical pupils,

Just like our catalina rattler.

They also share
the same type of venom

And give birth to live young...
Another check.

So the santa catalina snake
is indeed a type of rattlesnake.

Question is, how and why
did it become rattleless?

Nelson: So, it might be
as a form of camouflage.

Being camouflage means you can't
be seen in the environment.

Narrator:
Unlike other rattlesnakes,

The santa catalina rattler's
tail is camouflaged,

Just like the rest of its body.

So, did the catalina rattlers
lose their rattles

In order to become more stealthy
in pursuit of their prey?

Perhaps not.

But this wouldn't make sense
because every other rattlesnake

Everywhere else in the world
is a very efficient predator.

Narrator: They can strike
in just 50 milliseconds.

So fast that if you blink,
you really would miss it.

So, why would a rattlesnake need
to lose his rattle

To be a good predator?

Doesn't make sense.

Narrator: If losing your rattle

Doesn't make you
a better hunter,

Maybe we need to go back
to the reason

That rattlesnakes have rattles
in the first place.

Galante: They're a snake that
has evolved itself

An entirely unique
defense mechanism...

An object on the end of its tail
that it can shake like crazy

And rattle to send off
a warning signal to say,

"hey, I'm venomous,
I'm dangerous.

Leave me alone."

Narrator:
Most animals avoid tangling

With these snakes'
venom-filled fangs,

But there may be a downside

To the rattlesnakes'
early warning system.

Could the rattle actually
attract unwanted attention?

[ Bird screeches ]

So, perhaps in this instance,

When the isla catalina
rattlesnake rattles its tail,

It's actually alerting predators
to its whereabouts.

It's creating a beacon, saying,

"I'm right here,
come and eat me."

Riskin: So, maybe it's possible
that predators are the reason

That these snakes
have lost the rattle.

There are predators
that do eat snakes.

Things like hawks...

All kinds of animals
that will go after an easy meal,

And that rattle might be a way
of attracting predators.

Narrator: Isla santa catalina,
sea of cortez.

A scientific expedition
encounters

A rather unusual reptile.

Of the 36 species
of rattlesnake,

The santa catalina
snake has no rattle.

Why?

Well, despite their
fearsome reputation,

Some animals will prey
on rattlesnakes,

So maybe the rattle
was lost to avoid detection.

On catalina, one of those
predators is a surprise.

The rattlesnakes coexist
with feral pigs.

Narrator: So, one theory is...

Galante: Because pigs harass
rattlesnakes, that over time,

The rattlesnakes
have lost their rattles.

This would enable them
to hide better from these pigs

That are messing with them.

So could it be that pigs
have literally scared

The rattle out of rattlesnakes?

This is an interesting theory
because...

Well, pigs,
they love to eat snakes.

They will search out
rattlesnakes,

Stomp them, eat them.

It would be a good meal
for a little pig.

Narrator: Pigs are only one of
a handful of mammals resistant

To snake venom and they
can survive snake bites.

So, if pigs are not scared
of attacking snakes,

Could this be why the santa
catalina rattlers

Lost their rattles?

Maybe, but...

It's doubtful, though,
that pigs are the whole story.

There just aren't enough pigs

Where there are
these rattlesnakes.

Narrator: In fact, there are
very few predators

Of any kind living
on this island,

Making santa catalina
a pretty safe place

For the snakes to call home.

So instead, could this lack
of predators

Have caused the snakes
to shed their rattles?

Riskin: Places where there are
dangerous animals,

That rattle really comes
in handy to ward them off,

But on this island, there were
no animals to worry about.

So, it's not all that big
of a benefit to have the rattle.

Narrator: But why are the
island's missing predators

Important to our mystery?

The answer may lie in how
a rattlesnake's rattle

Is normally made.

So, what I have here is

One of the most beautiful
rattlesnake species on earth.

This is the spectacled
rattlesnake and look at him go.

Listen to that rattle hum away,

And when you look
at that rattle,

You realize there's a little
tiny bead in every single ring.

So what you can assume is that
the body's genes

Are telling it
to make that little bead.

Narrator:
A new bead or rattle segment

Is added every time
the snake sheds its skin.

The distinctive rattle sound
is made

Whenever these segments
smash into one another.

Galante: Now, in an area with
very few predators, over time,

What happens
is the snakes stop wasting

That valuable biological energy
to create this bead.

Narrator: Since arriving
on santa catalina,

These snakes have
gradually evolved

To stop growing
the one body part

They simply don't need anymore.

Over time, more snakes
continued to lose their rattle

Because it wasn't having
an adverse affect on them.

Now you have an entire
population

Of rattleless rattlesnakes.

A rattlesnake without a rattle.
How cool is that?

♪

Narrator: April 2016.

Nagarhole national park, india.

Scientists from the wildlife
conservation society

Are on a safari when they
stumble upon something strange.

Okay, so, it's putting
something in its mouth

And it's puffing it out.

Smoking, not good.

Narrator: April 2016.

Nagarhole national park, india.

Scientists encounter an elephant
acting strangely.

I have never seen
this behavior before.

To see an elephant blow
out a plumage of smoke,

That was very interesting.

Narrator: The elephant seems
to repeat this action

Again and again.

This indian elephant is picking
something up off of the ground,

Clearly chewing on it,
and then on his exhale,

This huge cloud of smoke

Is coming out
either side of his mouth

And just engulfing
his whole head,

And then he chews,
picks up another piece,

And does it again.

And it looks like he's smoking.

Narrator: But could this
elephant really be smoking?

I mean, when you look at it
at first,

It looks like it's pulling
on a cigarette

Or something like that,
but there's too much smoke

And there's no cigarette.

This is something else.

Narrator:
The local forestry department

Recently burnt areas
of the jungle

In an attempt to prevent future
forest fires from spreading.

This left behind
burnt wood and ash.

In this case, the elephant is
not foraging its typical diet,

But it is in fact
picking up with its trunk

And chewing on
and eating charcoal.

Narrator:
So, the elephant isn't smoking,

It's blowing the ash off pieces
of charcoal and chewing it.

This is new.

Until this video,

No one else had ever seen
an elephant eating charcoal.

Narrator: The mystery is,

Why eat charcoal
in the first place?

Perhaps it's using the charcoal
to help clean its teeth.

There's actually a lot of
different instances of animals

Using tools as dental tools
to aid in hygiene.

Narrator:
And charcoal is something

That can be used to clean
and even whiten our smiles.

So, is the smoking elephant
caring for its teeth?

Well, perhaps.

Daly: Teeth are a vital part
of an animal's life.

If a tooth was to become loose
or if it was to become sore,

That could really impede
the feeding of that animal

And they could also be in pain.

It's so important, actually,
that in some species,

They use tools to actually help
clean and maintain those teeth.

Galante: Long-tailed macaques
live in thailand,

And these animals
are very adaptable.

They live near a shrine
where people often frequent.

Narrator:
These monkeys have adopted

A strangely familiar routine

For their dental care...
Flossing.

Galante: They've learned that
if they collect human hair,

They can actually use it
as dental floss.

They sit around and actually
floss with human hair,

And just like you're human,

Kind of check it out
and then discard it.

Be like,
"yeah, my teeth are clean."

Narrator: So, is this elephant
using charcoal

To clean its ivories?

To find out,
we need to understand

How elephants' teeth work.

Elephant teeth are not
like our teeth.

They're weird.

New teeth come in
at the back of the mouth

And then everything
shifts forward

And then old teeth
fall out the front,

And they just
keep rotating through.

Daly: Elephants have six sets
of teeth

To keep up with
the sheer amount of food

That they're going through.

Narrator: With new teeth
growing all the time,

Elephants don't have the same
oral-hygiene concerns as we do,

So tooth care is ruled out.

So, we need to consider
something else.

Narrator: Perhaps there's
something inside the charcoal

The elephant is after.

After all, wood ash
does hold some minerals.

Maybe the charcoal
contains nutrients

That are in short supply,

And so maybe it's just trying
to fill out its diet.

It's like a vitamin.

Narrator: One of the most
sought-after minerals

In the natural world is salt.

Elephants have been known
to go to extreme lengths

To get salt in their diet.

Narrator: In kenya's mount
elgon national park,

Some exceptional elephants
have become experts

In harvesting salt
from the earth itself,

And they've passed the knowledge

Of how to reach it down
through generations.

Every evening, they descend deep
into dark cave tunnels

For six-hour shifts,
mining the salt-rich rocks.

These are the only elephants
in the world to do this.

The elephants will dig
into soft rock with their tusk,

Wearing down their tusk
while they do it,

Just to break up the dirt
so that they can eat it

And get the salt.

Narrator: They have been mining
like this

For thousands of years,

And in that time,
they've extended the entire cave

By over 170 meters
into the mountainside.

Such is the importance
to elephants of salt.

So, if there's salt in this
charcoal that the elephants

Are picking up,
it would make total sense

For them
to be putting it in their mouth.

Narrator: So, could this
elephant be after salt

In the charcoal?

Galante: I'm not convinced.

Charcoal does contain some salt
but not that much.

Not enough that an elephant
would be chewing on it.

Narrator:
As the largest land mammal,

An elephant would have to eat
a lot of charcoal

To supplement its diet.

So, if not for the salt,
why else are they eating it?

Might the charcoal
contain chemicals

That could benefit
the elephants' health?

Narrator: April 2016.

Nagarhole national park, india.

Scientists record
never-before-seen behavior...

An elephant eating charcoal.

Why is it doing this?

Is it possible the elephant is
using it as a type of medicine?

Animals across the world
use a variety of plants

And materials
to help stave off infection

Or protect themselves
from disease.

Narrator: Many animals have been
seen chewing charcoal.

Maybe they hold the answer
to the smoking elephant.

Red colobus monkeys in zanzibar

Have been seen
to ingest charcoal,

Which is meant to help
with settling their stomachs.

What charcoal can do
is it can treat poisoning

If an animal has
ingested toxins.

It can also act as a laxative
and it can help with digestion.

Narrator: So, it seems that
eating charcoal

Is not for tooth care

Or to consume
the salt minerals it contains.

Instead, it's a medicine
that will neutralize toxins

In the elephant's stomach.

Until now, we've seen
colobus monkeys eating charcoal

To presumably
settle their stomachs,

And now we have
this elephant footage

Showing that they may do
exactly the same thing.

It's pretty special.

Galante:
Charcoal is a natural filter.

It helps with stomach problems,

And, in fact, human beings
will buy charcoal pills

When they're having
upset stomachs.

Narrator:
So, this puffing pachyderm

Has raided nature's
medicine cabinet

To treat indigestion.