Nature (1982–…): Season 36, Episode 12 - Sex, Lies and Butterflies - full transcript
An exploration of the diversity of moths and butterflies from caterpillars to larva to chrysalis to winged flight. Camouflage and other anti-predatory tactics and uniqueness of different species and amazing feats and colors are de...
♪♪
If you had never
seen a butterfly,
you might not
believe they were real.
They are so colorful, they
can't help but be noticed,
and so fragile that being
noticed should spell their doom.
Yet butterflies are
truly among nature's
most surprising survivors...
taking on unique
powers of flight.
From a dark and
dangerous past...
butterflies have triumphed in
almost every place the planet.
They are masters of
deception and seduction,
and they're indispensable
to much of life on Earth.
This is the story
of how butterflies
have become one of the
great wonders of the world.
♪♪
♪♪
We don't really know
where the name
"butterfly" came from.
The origin of the
word is lost to time...
And in many respects,
butterflies themselves
are a mystery.
But we do know
they are remarkable.
There are butterfly
stories from every culture.
One Chinese legend
turned two tragic lovers
into butterflies some
1,600 years ago.
And that's what they've
come to symbolize most...
Transformation...
metamorphosis...
the ability to abandon
an earthbound body...
and take to the air
on gossamer wings.
Squint into a midsummer
meadow in bloom.
It's as though
the flowers can fly.
♪♪
But what if we followed
not our imaginations,
but real butterflies into the
worlds they actually live in?
What would we see then?
How did these incandescent
creatures come to be?
♪♪
In the wilds of
Mozambique, Africa,
a team of scientists
are tracking down
the story of how
butterflies began.
They've come to
Gorongosa National Park,
one of the world's great
centers of biodiversity.
♪♪
Armed with the tried and true
tools of the collection trade,
the team tries to get a sense
of all the butterflies
that live here.
♪♪
Oh!
Ho ho ho.
♪♪
Akito Kawahara
of the Florida Museum
of Natural History
studies the evolution and
diversity of invertebrates.
Especially of moths
and butterflies,
a vast group called
the Lepidoptera.
In Mozambique, we see
all kinds of new species
all the time and we're
also sampling butterflies
to try to get an idea of
when butterflies
evolved and came about.
We still don't know
much about them at all.
♪♪
It's thought that the
Lepidoptera arose
as flowering plants began
to flourish across the planet.
But there are so few traces
of these delicate creatures
in the fossil record,
Akito can only
discover their origins
by looking at the
ones alive today.
Yet, he can still step
deep into the past...
in the primal darkness
of the African night.
♪♪
The very air is thick with life.
These are creatures
from an ancient world.
♪♪
Akito and his team are
attempting to reach back
into the story of the
butterfly's older cousins...
Moths.
A Mantis. There's a mantis.
There's a mantis
on the lens here.
I know.
160,000 species of
moths described so far
and probably 500,000, maybe
a million species in the world.
We are just, just beginning to
understand what's happening.
This is a moth we want.
We want to cup that.
This is a white pyralid.
This is a white crambid.
From the astonishing
gathering of insects
drawn to the lights,
he handpicks the
characters he's interested in.
This is a noctuid...
about 150 maybe, 200?
Moths are primarily
creatures of the night.
The key to their connection
with brightly colored butterflies
may lie in the predators
that are also drawn
to this midnight swarm.
Bats.
They're hunting up high.
Yeah.
The bats have
brought Jesse Barber
of Boise State
University here tonight.
He's an expert on
the ecology of sound.
Together, Jesse and Akito
are investigating how a predator
and its prey shape each other.
We're trying to
figure out how bats
are driving moth evolution.
There's a bat. Is it in view?
Yep, Yep, right
through the space.
Nice!
As fast, insect hunting bats
course through the air,
Jesse and his team record
what we cannot hear...
The sounds of bat sonar.
The recordings are slowed down
to a frequency within our range.
Flying with mouths open,
the bats generate
high-speed sound signals
from their larynx,
"seeing" with sound
waves and echoes.
Pinpointing the
moths' locations,
the bats scoop them up in a
catcher's mitt-like membrane
that stretches
between their feet.
♪♪
Then Jesse's
ultrasonic microphones
pick up something
more surprising...
Moths sending out
their own signals
pitched at the same
frequencies as the bats' sonar.
♪♪
To try and understand
which moths are making
ultrasound back at bats,
we bring them into a
lab setting in the field
and play echolocation
calls back at them
and try and understand
who makes sound.
We then have to figure out why,
and we know form lab work
back at our
universities in the States
that part of the reason
they make sound
is to jam sonar.
Rolling.
Jesse and Akito are
attempting to unravel
millions of years
of a sonic arms race
we've never been able to hear.
Bats hunting with sonar, moths
fighting back by jamming it.
These moths are
actually screaming
at incredibly high
intensities back at bats.
Oh, my gosh!
Wow! Turning the gain down.
Lots of sound!
While there are still so
many mysteries to solve,
Akito and his team
of collaborators
have made an
extraordinary breakthrough.
Using DNA sequencing, he
is tracing the genetic origin
of all the butterflies
we've identified.
Remarkably, they all
share a single ancestor...
A tiny brown moth
that fled the night
some 50 million years ago,
driven, perhaps,
by the rise of bats
relentlessly hunting
the dark skies.
In a world full of light,
moths burst into color.
We call these daytime
fliers butterflies,
but they are really some
20,000 species of colorful moths
that have spread across every
continent except Antarctica.
♪♪
The most cosmopolitan
of all is the painted lady.
♪♪
She can be found throughout
Europe, from India to Asia,
from North into South
America, and all across Africa.
♪♪
With its bright
splashes of orange,
her body is both
beautiful and alien...
and it's equipped with
keen butterfly senses.
The tips of her legs can
"taste" the leaf she stands on.
♪♪
Her eyes have more
than 30,000 lenses.
Instead of a nose,
she has antennae that
catch the faintest scent.
And she hears with
membranes in her wings.
Our painted lady isn't just
resting with wings folded,
she's listening for danger.
But one of her most
remarkable features is what
we think of as a
tongue— A proboscis.
It's made of two long strands
that zip together
to form a tube.
She usually carries it
coiled, just below her head.
♪♪
♪♪
To eat is to drink,
so a butterfly simply
uncoils her proboscis,
and with the aid of a
micro-pump inside her head,
pumps liquid nourishment
up into her body.
♪♪
And it's not just
nectar they're drinking.
They can imbibe all
kinds of beverages
from lots of different surfaces.
Sap from tree bark
and mineral-rich waters
from sand banks and tidal edges.
Some even sip the blood, sweat,
and tears of various
hapless neighbors.
♪♪
Being able to mop
up many liquids
has helped butterflies
thrive all around the world.
And what's been good for
butterflies has been very good
for all the plants they feed on.
♪♪
Flowers prepare
for butterfly visits.
They make nectar
to offer a meal,
but it's actually a
form of seduction.
The real takeaway is pollen,
the agent of procreation.
Pollen resembles
a sticky powder,
and as the butterfly
sips from the flower,
its proboscis can't
help but pick some up.
But the butterfly
doesn't seem to mind...
or even seem to notice
that its proboscis is
encrusted with pollen.
It coils it up in the usual way,
and it's off to the next flower.
♪♪
The plant is counting
on the butterfly
to bring its pollen to
flowers of the same kind,
completing a sexual
connection the plant needs.
♪♪
That's how the
birds and the bees...
And butterflies, too...
Have helped plants
reproduce for a very long time.
♪♪
But then, there's the intriguing
case of the flame azalea tree.
♪♪
Flame azaleas are native
to the Appalachian
Mountains of Virginia,
and from late spring
to midsummer,
it's easy to see how
they got their name.
All along the high ridges,
bright yellow to blazing orange
blossoms burst
out like signal fires,
unmistakable beacons
to pollinators far and wide.
But while the flowers
are showy and obvious,
just how they are
pollinated is not.
Mary Jane Epps of
Mary Baldwin University
reveals that the mystery lies
in the flowers'
unusual architecture.
So, one of the
really cool things
about flame azalea flowers
is the way the reproductive
parts are situated.
So, you have the petals, which
are fused into this long tube,
and the nectar is actually born
down at the bottom of that tube.
And here, we have the anthers,
which are the pollen-bearing
part of the plant.
And sticking even
farther out of the flower...
And you'll notice
it's sort of curved
at a slightly different
angle often...
Is what's called the stigma,
that's the female
reproductive organ.
And so, for
pollination to occur,
which, of course, is
required for fruit to set
and seeds to form on a plant,
you have to have pollen
deposited on this stigma.
There are lots and
lots of different insects
that come to flame
azaleas... Various bees,
butterflies, flies,
even beetles.
Noticing a lot of these bees
would gather lots of pollen
but never make
contact with that stigma.
So, we started wondering
who actually does
the pollination here.
♪♪
The flower's design foils
even a large eastern
tiger swallowtail
as it comes for
a drink of nectar.
So here's a swallowtail...
coming right in to this azalea.
Then Mary Jane discovered
the telltale fingerprints
a butterfly leaves behind.
Wow. All of these have
butterfly wing scales on them.
As the butterfly drinks,
its wings constantly
brush against the anthers.
The faintest touch pulls
out a chain of pollen,
like a party streamer...
and with another wing beat,
deposits some on
the sticky stigma.
Pollination has begun!
This discovery
was a true surprise.
It's just the third case of
wing pollination ever recorded.
But as the swallowtails
flutter from tree to tree,
it appears their wings have
become an essential partner
in the sex life of
the flame azaleas.
♪♪
♪♪
A painted lady has her
own offspring to create...
and lays dozens of tiny
eggs of a surprising blue.
♪♪
Each egg is attached to
a leaf with a special glue
that keeps it in
place at any angle.
♪♪
They are jewel-like and
almost microscopically small.
She clusters them on leaves
the babies will be able to eat
when they hatch.
And that's the end
of her motherly duties.
♪♪
But in just five days,
a little caterpillar begins
to break out of its shell.
♪♪
The eggs were only
the size of a pinhead.
The baby caterpillars are
smaller than a grain of rice.
♪♪
Even the plant hairs
sprouting from the leaf
are giant obstacles for them.
♪♪
Almost nothing about
this little caterpillar
resembles its parents.
With 8 pairs of legs,
a black spiky suit,
and no wings at all,
it's an entirely
different animal.
♪♪
And its whole world is
confined to its host plant.
And so it eats.
The more it eats,
the faster it grows,
and thus begins a life of one
transformation after another.
Little painted ladies will
transition through 5 stages
called instars,
building a new body each time.
Every stage is a
mini metamorphosis
as hormones trigger
ongoing changes in
the caterpillar's body.
But unable to fly away,
they're an easy target.
♪♪
A young blue jay, no longer
being fed by its parents,
can make a good start on its own
with helpless
little caterpillars.
♪♪
But some caterpillars
are able to fight back.
A monarch is already set
on an elaborate
course of self-defense.
The milkweed it feeds on
is full of noxious chemicals,
and the caterpillar will store
them up and become noxious, too.
Some caterpillars are so toxic,
they can make their
predators really sick.
These plump, juicy-looking
characters are busy
weaponizing black cherry leaves
into a version of
hydrogen cyanide.
♪♪
All across the
butterfly kingdom,
20,000 species known so far,
20,00 different
caterpillars parade.
♪♪
Some glow a leafy green...
others wear
elaborate disguises...
or simply taste terrible.
♪♪
This one tries
looking like a snake!
♪♪
Sometimes, it's hard to see
what look they're going for.
♪♪
Others just look disgusting...
like bird droppings...
or even an
unappetizing fur ball.
♪♪
It's all to give them a chance
to eat and not be eaten.
It's a problem they
face all their lives.
So if they carry their noxious
chemicals into adulthood,
they want their
predators to know it.
♪♪
That foul-tasting
monarch caterpillar
passes its milkweed
toxins on to its butterfly form.
Predators learn
quickly not to eat it.
And so its cousin,
the queen butterfly,
has converged on the same look.
It, too, feeds on milkweed
and tastes just as bad.
By looking so similar,
it doubles down on
the warning signal
the monarch sends to predators.
But some butterflies get
away with a bold-faced lie.
This highly toxic
pipe-vine swallowtail
is loaded with plant acids.
Its beautiful markings
are copied by the
black swallowtail...
and a dark version of the
eastern tiger swallowtail.
It's very hard to
tell them all apart,
and that's precisely the point.
Two of them are
perfectly good to eat...
but they're hoping to
scare predators away
simply by looking like their
poisonous cousin, the pipe-vine.
But whether your
colors are true or false,
you can't fool all of the
predators all of the time.
Butterflies are such
an important prey
for so many creatures,
they live in constant danger
in every field and forest.
♪♪
When you're
surrounded by enemies,
it good to have an ally.
From deep in the
Peruvian Amazon,
a report has surfaced
of some strange behavior
between a butterfly
and one of the most
formidable creatures
in all the rainforest.
They're organized, disciplined,
relentless, adaptable.
The collective power of ants is
enough to intimidate anybody.
But Aaron Pomerantz,
a PhD student at the
University of California,
has come to Peru to follow up
on a startling
account of a butterfly
braving such an army.
So a collaborator of mine,
his name is Phil Torres,
he noticed that there
were these butterflies
that were sort of hanging out
with ants on bamboo stalks,
which was kind of odd because
ants usually treat butterflies
as they would anything else.
They'll attack them.
They'll, you know, use
them as a food source.
The bamboo itself is an
important part of the story.
From what I've been reading,
not a lot of things eat bamboo.
It's really tough, you
know, old, woody cellulose.
But Aaron began searching for
just the right young stalks
and made a
fascinating discovery.
Tiny ants swarm all over
the ends of the stalks,
drinking a sugary nectar
seeping from the tips of the shoots.
♪♪
At the base of the bamboo
there are these leaves.
So, as I pulled one back...
Oh, we got caterpillars!
There were ants
hovering over them,
and I thought, oh, man, this
might be the first time anyone
has ever seen the larval
stage for this butterfly.
Aaron had uncovered a
story that was new to science.
He had discovered the
unusual life cycle of a butterfly
called Adelotypa annulifera.
Its tiny caterpillars are
doted on by ferocious ants.
♪♪
Oh, very cool.
Then, Aaron noticed
that the caterpillars, too,
were drinking the bamboo sap,
all the while under the
protection of the ants.
If we actually
tried to get in there
and handle the caterpillar,
the ants would attack us.
You know, whether
you're a parasitoid wasp,
or a bird, or a human,
these ants are going to protect
them until their last breath.
♪♪
The caterpillars earn
this security service
by producing a sweet nectar of
their own from the bamboo sap.
It's highly nutritious
and rich in energy,
and the ants mob
the caterpillars
to gain access to
this special brew.
♪♪
But what of the butterflies?
How does this story end?
Aaron sets up a
time-lapse camera
focused on the tip
of a bamboo shoot.
The butterflies are very rare.
They're very skittish, so it
could be that our presence
is preventing them
from coming by,
but we're going to let
this sit and take an image
every set half hour or so.
And, if we're lucky, maybe
the butterfly will come by.
♪♪
Ah, there we go!
Left undisturbed for
hours in the rainforest,
the camera has
captured a glimpse
of these most
remarkable butterflies.
They, too, come to bamboo to
sip the nectar in a rare instance
of butterflies
and their caterpillars
relying on the same food.
The nectar appears
to fuel their entire lives.
And amazingly,
the ants allow it.
It's the only example
we know of where ants
and butterflies feed together.
And look closely at
the butterfly's wings.
Red spots grouped in threes
may be mimicking the ants
and doubling the
butterfly's defenses.
Instead of a butterfly, a bird
might look down and see nasty,
stinging insects,
while the ants, looking up,
see a reassuring
version of themselves.
With or without
bodyguards, a caterpillar's job
is to store up enough energy
to undergo one of the
greatest rites of passage
in all of nature.
♪♪
A painted lady has
reached her last instar
and finally stops eating.
She spins a bit of silk,
attaches herself to a stem,
and hangs head down.
Underneath her
final caterpillar skin,
she is once more
creating a new body,
but this time, it's
stunningly different
than the 5 bodies
she has made before.
♪♪
When she finally
wriggles free...
she is no longer
a caterpillar at all.
She has become a
chrysalis, a butterfly pupa.
Her new shape is already
a blueprint for the creature
she will ultimately be.
But now she's in the midst
of a transformation so radical,
science is still attempting
to decipher how she does it.
Her outer skin
dries and hardens.
For most of the next two weeks,
the dull casing of
skin looks dormant.
But inside, special cells
send out instructions
that complete a
miraculous metamorphosis.
♪♪
Then...
suddenly...
she splits that skin
open and is born again
as a fully formed butterfly!
♪♪
She seems surprised
by her unfamiliar body.
How strange her new
extended legs must feel.
♪♪
Her head now has
large, complex eyes.
Her jaws have been
replaced with a long proboscis.
Its two unruly strands
must be zipped together,
and she struggles to
get them under control.
♪♪
And now she has the
ultimate in new parts... wings!
Slowly, they unfurl.
♪♪
Finally, she takes flight,
joining a new
cohort of butterflies
trying out their wings
for the very first time.
♪♪
And the way they fly is unique.
♪♪
Butterflies have such
large wings for their size,
they contract their entire
bodies to move them.
♪♪
They lurch and flop around,
big wings laboring
through the air.
Their flight may look awkward,
but none of it is a mistake.
They are so maneuverable,
and their flight plan so erratic,
they're very hard for
predators to catch in the air.
Their large wings act
like an enormous rudder,
enabling a change in
direction with almost every flap.
♪♪
They hover by stroking
back through the swirling wake
they just created.
♪♪
They often clap their
wings behind their backs,
squeezing out a jet of air
to push themselves forward.
♪♪
Despite what it looks like,
they fly with complete control.
♪♪
Now they can feed on nectar.
But a butterfly doesn't
go through metamorphosis
just for a new kind of food.
If caterpillars were
made for eating,
butterflies are made for mating.
Caterpillars are just
juveniles, unable to breed,
their lives limited
to a leaf or two.
Now they are adults,
and wings open up a
world of possibilities.
They compete...
and flirt...
dancing in the air...
circling skyward
in a butterfly ballet.
♪♪
When they do mate,
they join at the abdomen,
facing away from each other.
♪♪
How long they stay
together varies widely
from couple to couple.
Incredibly, some partners
stay joined for hours.
♪♪
But not long after they part,
the female must find
the right host plant
on which to lay her eggs.
Painted ladies
are able to choose
among a hundred different plants
their caterpillars will eat.
Adults can survive on nectar
from thorny acacia trees.
And that brings their
story here to the edge
of the great Sahara
Desert in North Africa.
♪♪
This harsh, remote landscape in
the Anti-Atlas region of Morocco
is more of a moonscape
than a butterfly garden,
but it's the starting
point of a butterfly tale
so astonishing,
it's hard to believe.
Hey, hey, yes!
This is a... well, a very,
very old painted lady.
When you see one
butterfly like this,
you have to think what
happened during his life or her life.
Because you see all these
wings that are so broken?
So it's really a mystery what
happened to this butterfly.
Constanti Stefanescu
of the Natural History
Museum of Granollers
has come from Spain to
unravel the painted ladies'
remarkable story.
Intriguingly, the first to
appear here in the fall
are already at the
end of their lives.
They have to be coming
from someplace else.
So Constanti analyzed
stable isotopes of hydrogen
in their wings
to identify the region where
the butterflies were born.
The results were a revelation.
These worn and torn
painted ladies, he discovered,
had undertaken an
impossible journey,
some arriving in Morocco from
as far away as the Arctic Circle.
Their amazing feat of
flying and endurance begins
as the cool, wet
winter in the desert
turns to a hot, dry spring.
Host plants and nectar
sources begin to wither.
Painted ladies suddenly depart,
turning north with
an urgent purpose,
looking for fresh
food for themselves
and their caterpillars.
After crossing the
Atlas Mountains,
it's a short hop from
Morocco to Spain.
But painted ladies
even farther south
departed months ago from
the tropical edge of the Sahara,
riding warm African winds
all the way across the desert
and the Mediterranean Sea.
They arrive in Rome, Marseille,
and Barcelona,
and seek out some
much needed nectar.
Then they mate and lay eggs.
In six to eight weeks, a new
generation picks up the baton
and continues north.
They cross the
Alps, fly up the Rhine,
spreading all throughout Europe,
stopping to create new
generations all along the way.
By the end of summer,
they finally reach
high into Scandinavia...
and then suddenly disappear!
What happens next has been
one of the long-standing mysteries
in natural history.
No one had ever witnessed
the return flight south
of the painted ladies.
They simply flew to
the north and vanished.
It was long thought they
all died in the autumn.
But Constanti Stefanescu knew
that somehow they
were returning to Africa.
So he turned to Jason Chapman
of Rothamsted Research in the UK.
Jason studies the emerging
field of aeroecology...
How animals travel
up in the atmosphere.
♪♪
This green drum-like apparatus
is Jason's Vertical
Looking Radar.
It sends pulses of
electromagnetic waves
straight up, 4,000
feet into the sky.
♪♪
Any insect, bird, or bat
that flies through its beam
will bounce a signal
back to the dish.
Okay.
But to interpret
what the radar sees
and physically confirm
which animals are
up in the atmosphere,
Jason and his team send
aloft a series of aerial nets
attached to
high-flying balloons.
Well, the really
exciting thing about
the new field of aeroecology
is that we now have the tools
that can allow us to figure out
how insects are
using wind currents
or being affected
by wind currents
to carry out their migrations.
Are we up?
♪♪
The sampling goes
on day and night,
and as the nets go up,
they recede into a sky so
vast, it seems an impossible task
to measure and understand
what's going on up there.
But Jason and his radar and nets
have revealed an
unimagined global highway
and solved the mystery
of the vanishing butterflies.
At any given hour, thousands
of feet above our heads,
there are literally trillions
of insects riding the winds.
Among them are
millions of painted ladies.
As autumn arrives
high in Northern Europe,
and their resources
are running out,
painted ladies do disappear.
They launch themselves
into prevailing winds
1,500 feet above the ground.
Guided by internal
compasses set on the sun,
they begin to stream south,
flying at 30 miles per hour
and up to 300 miles a day.
Though these butterflies
have never been there before,
they are returning to the
land of their ancestors.
If conditions are good,
this one generation will
reach Africa in a week.
Millions will
continue flying south,
across the Sahara
to the tropics.
From Africa to Scandinavia
and back, painted ladies
will have travelled
some 9,000 miles,
3,000 miles farther than their
famous cousins, the monarchs.
They are champions
of distance and altitude,
completing the longest migration
of any insect ever discovered.
♪♪
Many are bound for Morocco,
where Constanti
Stefanescu and his team
have been waiting for them.
He can only imagine
what they've been through
and how such a
small, fragile creature
has accomplished
such an enormous feat.
♪♪
This is a very old painted lady
that has been attacked
by a bird, probably.
But she's still
visiting the flowers
and trying to obtain food.
Hmm.
That's a male,
a migrant that has come
probably from Europe.
In a one hour or so, he
will start to defend territories
and try to obtain a mate.
♪♪
And so, as one butterfly's story
comes to an end,
another's is just beginning.
Painted ladies pass their torch
on in a never-ending journey...
from butterfly...
to egg...
to caterpillar...
to chrysalis...
to butterfly...
in a ceaseless cycle
of transformation.
♪♪
They are both
ephemeral and eternal.
And perhaps that's what we see
when we look at
real butterflies...
delicate but enduring heroes
in the long game of life.
♪♪
♪♪
To learn more about what you've
seen on this "Nature" program,
♪♪
If you had never
seen a butterfly,
you might not
believe they were real.
They are so colorful, they
can't help but be noticed,
and so fragile that being
noticed should spell their doom.
Yet butterflies are
truly among nature's
most surprising survivors...
taking on unique
powers of flight.
From a dark and
dangerous past...
butterflies have triumphed in
almost every place the planet.
They are masters of
deception and seduction,
and they're indispensable
to much of life on Earth.
This is the story
of how butterflies
have become one of the
great wonders of the world.
♪♪
♪♪
We don't really know
where the name
"butterfly" came from.
The origin of the
word is lost to time...
And in many respects,
butterflies themselves
are a mystery.
But we do know
they are remarkable.
There are butterfly
stories from every culture.
One Chinese legend
turned two tragic lovers
into butterflies some
1,600 years ago.
And that's what they've
come to symbolize most...
Transformation...
metamorphosis...
the ability to abandon
an earthbound body...
and take to the air
on gossamer wings.
Squint into a midsummer
meadow in bloom.
It's as though
the flowers can fly.
♪♪
But what if we followed
not our imaginations,
but real butterflies into the
worlds they actually live in?
What would we see then?
How did these incandescent
creatures come to be?
♪♪
In the wilds of
Mozambique, Africa,
a team of scientists
are tracking down
the story of how
butterflies began.
They've come to
Gorongosa National Park,
one of the world's great
centers of biodiversity.
♪♪
Armed with the tried and true
tools of the collection trade,
the team tries to get a sense
of all the butterflies
that live here.
♪♪
Oh!
Ho ho ho.
♪♪
Akito Kawahara
of the Florida Museum
of Natural History
studies the evolution and
diversity of invertebrates.
Especially of moths
and butterflies,
a vast group called
the Lepidoptera.
In Mozambique, we see
all kinds of new species
all the time and we're
also sampling butterflies
to try to get an idea of
when butterflies
evolved and came about.
We still don't know
much about them at all.
♪♪
It's thought that the
Lepidoptera arose
as flowering plants began
to flourish across the planet.
But there are so few traces
of these delicate creatures
in the fossil record,
Akito can only
discover their origins
by looking at the
ones alive today.
Yet, he can still step
deep into the past...
in the primal darkness
of the African night.
♪♪
The very air is thick with life.
These are creatures
from an ancient world.
♪♪
Akito and his team are
attempting to reach back
into the story of the
butterfly's older cousins...
Moths.
A Mantis. There's a mantis.
There's a mantis
on the lens here.
I know.
160,000 species of
moths described so far
and probably 500,000, maybe
a million species in the world.
We are just, just beginning to
understand what's happening.
This is a moth we want.
We want to cup that.
This is a white pyralid.
This is a white crambid.
From the astonishing
gathering of insects
drawn to the lights,
he handpicks the
characters he's interested in.
This is a noctuid...
about 150 maybe, 200?
Moths are primarily
creatures of the night.
The key to their connection
with brightly colored butterflies
may lie in the predators
that are also drawn
to this midnight swarm.
Bats.
They're hunting up high.
Yeah.
The bats have
brought Jesse Barber
of Boise State
University here tonight.
He's an expert on
the ecology of sound.
Together, Jesse and Akito
are investigating how a predator
and its prey shape each other.
We're trying to
figure out how bats
are driving moth evolution.
There's a bat. Is it in view?
Yep, Yep, right
through the space.
Nice!
As fast, insect hunting bats
course through the air,
Jesse and his team record
what we cannot hear...
The sounds of bat sonar.
The recordings are slowed down
to a frequency within our range.
Flying with mouths open,
the bats generate
high-speed sound signals
from their larynx,
"seeing" with sound
waves and echoes.
Pinpointing the
moths' locations,
the bats scoop them up in a
catcher's mitt-like membrane
that stretches
between their feet.
♪♪
Then Jesse's
ultrasonic microphones
pick up something
more surprising...
Moths sending out
their own signals
pitched at the same
frequencies as the bats' sonar.
♪♪
To try and understand
which moths are making
ultrasound back at bats,
we bring them into a
lab setting in the field
and play echolocation
calls back at them
and try and understand
who makes sound.
We then have to figure out why,
and we know form lab work
back at our
universities in the States
that part of the reason
they make sound
is to jam sonar.
Rolling.
Jesse and Akito are
attempting to unravel
millions of years
of a sonic arms race
we've never been able to hear.
Bats hunting with sonar, moths
fighting back by jamming it.
These moths are
actually screaming
at incredibly high
intensities back at bats.
Oh, my gosh!
Wow! Turning the gain down.
Lots of sound!
While there are still so
many mysteries to solve,
Akito and his team
of collaborators
have made an
extraordinary breakthrough.
Using DNA sequencing, he
is tracing the genetic origin
of all the butterflies
we've identified.
Remarkably, they all
share a single ancestor...
A tiny brown moth
that fled the night
some 50 million years ago,
driven, perhaps,
by the rise of bats
relentlessly hunting
the dark skies.
In a world full of light,
moths burst into color.
We call these daytime
fliers butterflies,
but they are really some
20,000 species of colorful moths
that have spread across every
continent except Antarctica.
♪♪
The most cosmopolitan
of all is the painted lady.
♪♪
She can be found throughout
Europe, from India to Asia,
from North into South
America, and all across Africa.
♪♪
With its bright
splashes of orange,
her body is both
beautiful and alien...
and it's equipped with
keen butterfly senses.
The tips of her legs can
"taste" the leaf she stands on.
♪♪
Her eyes have more
than 30,000 lenses.
Instead of a nose,
she has antennae that
catch the faintest scent.
And she hears with
membranes in her wings.
Our painted lady isn't just
resting with wings folded,
she's listening for danger.
But one of her most
remarkable features is what
we think of as a
tongue— A proboscis.
It's made of two long strands
that zip together
to form a tube.
She usually carries it
coiled, just below her head.
♪♪
♪♪
To eat is to drink,
so a butterfly simply
uncoils her proboscis,
and with the aid of a
micro-pump inside her head,
pumps liquid nourishment
up into her body.
♪♪
And it's not just
nectar they're drinking.
They can imbibe all
kinds of beverages
from lots of different surfaces.
Sap from tree bark
and mineral-rich waters
from sand banks and tidal edges.
Some even sip the blood, sweat,
and tears of various
hapless neighbors.
♪♪
Being able to mop
up many liquids
has helped butterflies
thrive all around the world.
And what's been good for
butterflies has been very good
for all the plants they feed on.
♪♪
Flowers prepare
for butterfly visits.
They make nectar
to offer a meal,
but it's actually a
form of seduction.
The real takeaway is pollen,
the agent of procreation.
Pollen resembles
a sticky powder,
and as the butterfly
sips from the flower,
its proboscis can't
help but pick some up.
But the butterfly
doesn't seem to mind...
or even seem to notice
that its proboscis is
encrusted with pollen.
It coils it up in the usual way,
and it's off to the next flower.
♪♪
The plant is counting
on the butterfly
to bring its pollen to
flowers of the same kind,
completing a sexual
connection the plant needs.
♪♪
That's how the
birds and the bees...
And butterflies, too...
Have helped plants
reproduce for a very long time.
♪♪
But then, there's the intriguing
case of the flame azalea tree.
♪♪
Flame azaleas are native
to the Appalachian
Mountains of Virginia,
and from late spring
to midsummer,
it's easy to see how
they got their name.
All along the high ridges,
bright yellow to blazing orange
blossoms burst
out like signal fires,
unmistakable beacons
to pollinators far and wide.
But while the flowers
are showy and obvious,
just how they are
pollinated is not.
Mary Jane Epps of
Mary Baldwin University
reveals that the mystery lies
in the flowers'
unusual architecture.
So, one of the
really cool things
about flame azalea flowers
is the way the reproductive
parts are situated.
So, you have the petals, which
are fused into this long tube,
and the nectar is actually born
down at the bottom of that tube.
And here, we have the anthers,
which are the pollen-bearing
part of the plant.
And sticking even
farther out of the flower...
And you'll notice
it's sort of curved
at a slightly different
angle often...
Is what's called the stigma,
that's the female
reproductive organ.
And so, for
pollination to occur,
which, of course, is
required for fruit to set
and seeds to form on a plant,
you have to have pollen
deposited on this stigma.
There are lots and
lots of different insects
that come to flame
azaleas... Various bees,
butterflies, flies,
even beetles.
Noticing a lot of these bees
would gather lots of pollen
but never make
contact with that stigma.
So, we started wondering
who actually does
the pollination here.
♪♪
The flower's design foils
even a large eastern
tiger swallowtail
as it comes for
a drink of nectar.
So here's a swallowtail...
coming right in to this azalea.
Then Mary Jane discovered
the telltale fingerprints
a butterfly leaves behind.
Wow. All of these have
butterfly wing scales on them.
As the butterfly drinks,
its wings constantly
brush against the anthers.
The faintest touch pulls
out a chain of pollen,
like a party streamer...
and with another wing beat,
deposits some on
the sticky stigma.
Pollination has begun!
This discovery
was a true surprise.
It's just the third case of
wing pollination ever recorded.
But as the swallowtails
flutter from tree to tree,
it appears their wings have
become an essential partner
in the sex life of
the flame azaleas.
♪♪
♪♪
A painted lady has her
own offspring to create...
and lays dozens of tiny
eggs of a surprising blue.
♪♪
Each egg is attached to
a leaf with a special glue
that keeps it in
place at any angle.
♪♪
They are jewel-like and
almost microscopically small.
She clusters them on leaves
the babies will be able to eat
when they hatch.
And that's the end
of her motherly duties.
♪♪
But in just five days,
a little caterpillar begins
to break out of its shell.
♪♪
The eggs were only
the size of a pinhead.
The baby caterpillars are
smaller than a grain of rice.
♪♪
Even the plant hairs
sprouting from the leaf
are giant obstacles for them.
♪♪
Almost nothing about
this little caterpillar
resembles its parents.
With 8 pairs of legs,
a black spiky suit,
and no wings at all,
it's an entirely
different animal.
♪♪
And its whole world is
confined to its host plant.
And so it eats.
The more it eats,
the faster it grows,
and thus begins a life of one
transformation after another.
Little painted ladies will
transition through 5 stages
called instars,
building a new body each time.
Every stage is a
mini metamorphosis
as hormones trigger
ongoing changes in
the caterpillar's body.
But unable to fly away,
they're an easy target.
♪♪
A young blue jay, no longer
being fed by its parents,
can make a good start on its own
with helpless
little caterpillars.
♪♪
But some caterpillars
are able to fight back.
A monarch is already set
on an elaborate
course of self-defense.
The milkweed it feeds on
is full of noxious chemicals,
and the caterpillar will store
them up and become noxious, too.
Some caterpillars are so toxic,
they can make their
predators really sick.
These plump, juicy-looking
characters are busy
weaponizing black cherry leaves
into a version of
hydrogen cyanide.
♪♪
All across the
butterfly kingdom,
20,000 species known so far,
20,00 different
caterpillars parade.
♪♪
Some glow a leafy green...
others wear
elaborate disguises...
or simply taste terrible.
♪♪
This one tries
looking like a snake!
♪♪
Sometimes, it's hard to see
what look they're going for.
♪♪
Others just look disgusting...
like bird droppings...
or even an
unappetizing fur ball.
♪♪
It's all to give them a chance
to eat and not be eaten.
It's a problem they
face all their lives.
So if they carry their noxious
chemicals into adulthood,
they want their
predators to know it.
♪♪
That foul-tasting
monarch caterpillar
passes its milkweed
toxins on to its butterfly form.
Predators learn
quickly not to eat it.
And so its cousin,
the queen butterfly,
has converged on the same look.
It, too, feeds on milkweed
and tastes just as bad.
By looking so similar,
it doubles down on
the warning signal
the monarch sends to predators.
But some butterflies get
away with a bold-faced lie.
This highly toxic
pipe-vine swallowtail
is loaded with plant acids.
Its beautiful markings
are copied by the
black swallowtail...
and a dark version of the
eastern tiger swallowtail.
It's very hard to
tell them all apart,
and that's precisely the point.
Two of them are
perfectly good to eat...
but they're hoping to
scare predators away
simply by looking like their
poisonous cousin, the pipe-vine.
But whether your
colors are true or false,
you can't fool all of the
predators all of the time.
Butterflies are such
an important prey
for so many creatures,
they live in constant danger
in every field and forest.
♪♪
When you're
surrounded by enemies,
it good to have an ally.
From deep in the
Peruvian Amazon,
a report has surfaced
of some strange behavior
between a butterfly
and one of the most
formidable creatures
in all the rainforest.
They're organized, disciplined,
relentless, adaptable.
The collective power of ants is
enough to intimidate anybody.
But Aaron Pomerantz,
a PhD student at the
University of California,
has come to Peru to follow up
on a startling
account of a butterfly
braving such an army.
So a collaborator of mine,
his name is Phil Torres,
he noticed that there
were these butterflies
that were sort of hanging out
with ants on bamboo stalks,
which was kind of odd because
ants usually treat butterflies
as they would anything else.
They'll attack them.
They'll, you know, use
them as a food source.
The bamboo itself is an
important part of the story.
From what I've been reading,
not a lot of things eat bamboo.
It's really tough, you
know, old, woody cellulose.
But Aaron began searching for
just the right young stalks
and made a
fascinating discovery.
Tiny ants swarm all over
the ends of the stalks,
drinking a sugary nectar
seeping from the tips of the shoots.
♪♪
At the base of the bamboo
there are these leaves.
So, as I pulled one back...
Oh, we got caterpillars!
There were ants
hovering over them,
and I thought, oh, man, this
might be the first time anyone
has ever seen the larval
stage for this butterfly.
Aaron had uncovered a
story that was new to science.
He had discovered the
unusual life cycle of a butterfly
called Adelotypa annulifera.
Its tiny caterpillars are
doted on by ferocious ants.
♪♪
Oh, very cool.
Then, Aaron noticed
that the caterpillars, too,
were drinking the bamboo sap,
all the while under the
protection of the ants.
If we actually
tried to get in there
and handle the caterpillar,
the ants would attack us.
You know, whether
you're a parasitoid wasp,
or a bird, or a human,
these ants are going to protect
them until their last breath.
♪♪
The caterpillars earn
this security service
by producing a sweet nectar of
their own from the bamboo sap.
It's highly nutritious
and rich in energy,
and the ants mob
the caterpillars
to gain access to
this special brew.
♪♪
But what of the butterflies?
How does this story end?
Aaron sets up a
time-lapse camera
focused on the tip
of a bamboo shoot.
The butterflies are very rare.
They're very skittish, so it
could be that our presence
is preventing them
from coming by,
but we're going to let
this sit and take an image
every set half hour or so.
And, if we're lucky, maybe
the butterfly will come by.
♪♪
Ah, there we go!
Left undisturbed for
hours in the rainforest,
the camera has
captured a glimpse
of these most
remarkable butterflies.
They, too, come to bamboo to
sip the nectar in a rare instance
of butterflies
and their caterpillars
relying on the same food.
The nectar appears
to fuel their entire lives.
And amazingly,
the ants allow it.
It's the only example
we know of where ants
and butterflies feed together.
And look closely at
the butterfly's wings.
Red spots grouped in threes
may be mimicking the ants
and doubling the
butterfly's defenses.
Instead of a butterfly, a bird
might look down and see nasty,
stinging insects,
while the ants, looking up,
see a reassuring
version of themselves.
With or without
bodyguards, a caterpillar's job
is to store up enough energy
to undergo one of the
greatest rites of passage
in all of nature.
♪♪
A painted lady has
reached her last instar
and finally stops eating.
She spins a bit of silk,
attaches herself to a stem,
and hangs head down.
Underneath her
final caterpillar skin,
she is once more
creating a new body,
but this time, it's
stunningly different
than the 5 bodies
she has made before.
♪♪
When she finally
wriggles free...
she is no longer
a caterpillar at all.
She has become a
chrysalis, a butterfly pupa.
Her new shape is already
a blueprint for the creature
she will ultimately be.
But now she's in the midst
of a transformation so radical,
science is still attempting
to decipher how she does it.
Her outer skin
dries and hardens.
For most of the next two weeks,
the dull casing of
skin looks dormant.
But inside, special cells
send out instructions
that complete a
miraculous metamorphosis.
♪♪
Then...
suddenly...
she splits that skin
open and is born again
as a fully formed butterfly!
♪♪
She seems surprised
by her unfamiliar body.
How strange her new
extended legs must feel.
♪♪
Her head now has
large, complex eyes.
Her jaws have been
replaced with a long proboscis.
Its two unruly strands
must be zipped together,
and she struggles to
get them under control.
♪♪
And now she has the
ultimate in new parts... wings!
Slowly, they unfurl.
♪♪
Finally, she takes flight,
joining a new
cohort of butterflies
trying out their wings
for the very first time.
♪♪
And the way they fly is unique.
♪♪
Butterflies have such
large wings for their size,
they contract their entire
bodies to move them.
♪♪
They lurch and flop around,
big wings laboring
through the air.
Their flight may look awkward,
but none of it is a mistake.
They are so maneuverable,
and their flight plan so erratic,
they're very hard for
predators to catch in the air.
Their large wings act
like an enormous rudder,
enabling a change in
direction with almost every flap.
♪♪
They hover by stroking
back through the swirling wake
they just created.
♪♪
They often clap their
wings behind their backs,
squeezing out a jet of air
to push themselves forward.
♪♪
Despite what it looks like,
they fly with complete control.
♪♪
Now they can feed on nectar.
But a butterfly doesn't
go through metamorphosis
just for a new kind of food.
If caterpillars were
made for eating,
butterflies are made for mating.
Caterpillars are just
juveniles, unable to breed,
their lives limited
to a leaf or two.
Now they are adults,
and wings open up a
world of possibilities.
They compete...
and flirt...
dancing in the air...
circling skyward
in a butterfly ballet.
♪♪
When they do mate,
they join at the abdomen,
facing away from each other.
♪♪
How long they stay
together varies widely
from couple to couple.
Incredibly, some partners
stay joined for hours.
♪♪
But not long after they part,
the female must find
the right host plant
on which to lay her eggs.
Painted ladies
are able to choose
among a hundred different plants
their caterpillars will eat.
Adults can survive on nectar
from thorny acacia trees.
And that brings their
story here to the edge
of the great Sahara
Desert in North Africa.
♪♪
This harsh, remote landscape in
the Anti-Atlas region of Morocco
is more of a moonscape
than a butterfly garden,
but it's the starting
point of a butterfly tale
so astonishing,
it's hard to believe.
Hey, hey, yes!
This is a... well, a very,
very old painted lady.
When you see one
butterfly like this,
you have to think what
happened during his life or her life.
Because you see all these
wings that are so broken?
So it's really a mystery what
happened to this butterfly.
Constanti Stefanescu
of the Natural History
Museum of Granollers
has come from Spain to
unravel the painted ladies'
remarkable story.
Intriguingly, the first to
appear here in the fall
are already at the
end of their lives.
They have to be coming
from someplace else.
So Constanti analyzed
stable isotopes of hydrogen
in their wings
to identify the region where
the butterflies were born.
The results were a revelation.
These worn and torn
painted ladies, he discovered,
had undertaken an
impossible journey,
some arriving in Morocco from
as far away as the Arctic Circle.
Their amazing feat of
flying and endurance begins
as the cool, wet
winter in the desert
turns to a hot, dry spring.
Host plants and nectar
sources begin to wither.
Painted ladies suddenly depart,
turning north with
an urgent purpose,
looking for fresh
food for themselves
and their caterpillars.
After crossing the
Atlas Mountains,
it's a short hop from
Morocco to Spain.
But painted ladies
even farther south
departed months ago from
the tropical edge of the Sahara,
riding warm African winds
all the way across the desert
and the Mediterranean Sea.
They arrive in Rome, Marseille,
and Barcelona,
and seek out some
much needed nectar.
Then they mate and lay eggs.
In six to eight weeks, a new
generation picks up the baton
and continues north.
They cross the
Alps, fly up the Rhine,
spreading all throughout Europe,
stopping to create new
generations all along the way.
By the end of summer,
they finally reach
high into Scandinavia...
and then suddenly disappear!
What happens next has been
one of the long-standing mysteries
in natural history.
No one had ever witnessed
the return flight south
of the painted ladies.
They simply flew to
the north and vanished.
It was long thought they
all died in the autumn.
But Constanti Stefanescu knew
that somehow they
were returning to Africa.
So he turned to Jason Chapman
of Rothamsted Research in the UK.
Jason studies the emerging
field of aeroecology...
How animals travel
up in the atmosphere.
♪♪
This green drum-like apparatus
is Jason's Vertical
Looking Radar.
It sends pulses of
electromagnetic waves
straight up, 4,000
feet into the sky.
♪♪
Any insect, bird, or bat
that flies through its beam
will bounce a signal
back to the dish.
Okay.
But to interpret
what the radar sees
and physically confirm
which animals are
up in the atmosphere,
Jason and his team send
aloft a series of aerial nets
attached to
high-flying balloons.
Well, the really
exciting thing about
the new field of aeroecology
is that we now have the tools
that can allow us to figure out
how insects are
using wind currents
or being affected
by wind currents
to carry out their migrations.
Are we up?
♪♪
The sampling goes
on day and night,
and as the nets go up,
they recede into a sky so
vast, it seems an impossible task
to measure and understand
what's going on up there.
But Jason and his radar and nets
have revealed an
unimagined global highway
and solved the mystery
of the vanishing butterflies.
At any given hour, thousands
of feet above our heads,
there are literally trillions
of insects riding the winds.
Among them are
millions of painted ladies.
As autumn arrives
high in Northern Europe,
and their resources
are running out,
painted ladies do disappear.
They launch themselves
into prevailing winds
1,500 feet above the ground.
Guided by internal
compasses set on the sun,
they begin to stream south,
flying at 30 miles per hour
and up to 300 miles a day.
Though these butterflies
have never been there before,
they are returning to the
land of their ancestors.
If conditions are good,
this one generation will
reach Africa in a week.
Millions will
continue flying south,
across the Sahara
to the tropics.
From Africa to Scandinavia
and back, painted ladies
will have travelled
some 9,000 miles,
3,000 miles farther than their
famous cousins, the monarchs.
They are champions
of distance and altitude,
completing the longest migration
of any insect ever discovered.
♪♪
Many are bound for Morocco,
where Constanti
Stefanescu and his team
have been waiting for them.
He can only imagine
what they've been through
and how such a
small, fragile creature
has accomplished
such an enormous feat.
♪♪
This is a very old painted lady
that has been attacked
by a bird, probably.
But she's still
visiting the flowers
and trying to obtain food.
Hmm.
That's a male,
a migrant that has come
probably from Europe.
In a one hour or so, he
will start to defend territories
and try to obtain a mate.
♪♪
And so, as one butterfly's story
comes to an end,
another's is just beginning.
Painted ladies pass their torch
on in a never-ending journey...
from butterfly...
to egg...
to caterpillar...
to chrysalis...
to butterfly...
in a ceaseless cycle
of transformation.
♪♪
They are both
ephemeral and eternal.
And perhaps that's what we see
when we look at
real butterflies...
delicate but enduring heroes
in the long game of life.
♪♪
♪♪
To learn more about what you've
seen on this "Nature" program,
♪♪