All language subtitles for Insect Worlds 1of3 1080i Them And Us

Our planet is the greatest
living puzzle in the universe.

A collection of worlds

within worlds.

Each one a network of relationships

and connections

between all their living parts

leading to the diverse
and complex world we live in.

And at the heart
of many of these worlds

is a very special group of animals.

The insects and their close
relatives,

the arachnids and crustaceans,

classed together as the arthropods.

Together, they account for 80%
of all animal species on our planet.

In these three specials,

we're going to explore
the connections and relationships

that they have with us,
our planet

and with each other.

Ultimately to understand
how this group

hold the key to life itself

inside nature's microworlds.

Humans evolved around
200,000 years ago

into a world that was dominated
by the arthropods.

In that time, we've learnt
to live alongside each other,

taking the benefits and putting up
with some of the annoyances.

But do we understand
what life would be like

without this group of animals?

How many of us really know

how intricately linked
our lives have become

that, without the arthropods,
life as we know it would not exist?

Some even question

if survival of the human race
would be possible at all.

But how can this be?

What have the arthropods
ever done for us?

The ways they affect human life
are diverse and far reaching

and to really understand
the importance of this influence,

we need to unpick the relationships,

both good and bad,

that we have with the arthropods.

One of the most intriguing ways
they influence us

occurs in the forests of Kenya.

These driver ants
are searching for food.

They're efficient hunters

moving through the forest
like a tidal wave.

They'll eat any living animal
in their path.

Colonies can number up to 22 million

and it's said that even elephants
will turn and flee

when they see them coming.

These lethal predators
are actually totally blind.

They rely on touch, smell and
chemical signals to find their way.

The soldiers flank the raiding
columns of workers

with immense jaws raised.

Anything that can't outrun them

risks becoming their prey.

This is perhaps how most of us
view arthropods -

creepy crawlies that are
nothing more than a problem.

But their presence is actually

a real asset for these villagers.

The ants can capture up to
100,000 insects in a single raid,

providing invaluable pest control
for the farmers.

Pests inside homes and
in surrounding fields are removed,

dismembered and devoured.

In fact, the whole place is given
a five-star ant clean-up.

Thanks to their highly effective
cleaning raids,

these ants play a key role

in the lives of the locals.

But arthropods can provide us

with something even more important
than a service.

They can provide us with one
of the essential elements of life.

900 miles south of Kenya

lies Lake Malawi.

Beneath the water,
something's stirring.

Trillions and trillions of lake fly
larvae are getting ready to emerge.

After many months buried
in the sediment on the lake floor,

they'll take to the air to mate.

Towers of mating flies stretch
hundreds of metres into the air.

Like smoke, they rise

from the surface of the lake.

The towers of flies are swept
by the wind towards the shore

and towards human habitation.

Here, they cloak vegetation

and engulf whole forests
and villages in their path.

This may seem like an annoyance,

but, actually, these flies
present great opportunity.

Villagers sweep baskets
through the air to catch the flies.

The biomass of these flies
is equivalent to huge herds of game

that roam the surrounding plains,

but they're far easier to catch.

The flies are then made into patties

and fried in hot oil.

Each patty contains
half a million flies

and has seven times more protein
than the average beef burger.

For people who have little
protein in their diet,

this can be a lifesaver.

It may feel a long way from our idea
of a perfect meal,

but the importance
of eating arthropods

shouldn't be underestimated.

Over 11 million tonnes
of crustaceans

are consumed by humans every year.

In Botswana, the mopane worm
collection industry

is worth millions of pounds
each year.

For 2.5 billion people worldwide,

insects are a vital source of food.

More than a thousand insect species

form a regular part
of the human diet.

Rich in vitamins,
protein and minerals.

It's mainly in the West

that people are uncomfortable
with the idea of eating insects.

But the United Nations believe

that eating insects
instead of mammal meat

may provide a solution
to stamping out famine

and reducing climate change.

The raising of livestock
such as cows, pigs and sheep

occupies two thirds
of the world's farmland

and generates 20%
of all greenhouse gases.

With the human population
projected to reach nine billion

in just 40 years' time,

the consumption of arthropods

could provide a healthy Earth-saving
measure.

So, in the future,
arthropods have the potential

to address our global food crisis.

That's no small claim.

But they've also played
an enormous role in shaping our past

to such an extent that human life,
as we know it,

would not exist if it weren't
for this next arthropod product.

It all started with a cocoon

and a beautiful piece of cloth.

China - home to a billion people

and a very special arthropod.

This is a silk worm caterpillar.

They eat only mulberry leaves.

And, after 50 days of feeding,

they'll be 10,000 times heavier
and ready to transform.

25% of their body mass
is made up of silk glands.

They spin a cocoon
using a single thread

which can be over 900 metres
in length.

And it's this silk that forms
the basis of an industry

that's shaped our history

and today, has a commercial value

of up to £300 million.

The cocoons are boiled and precious
silken threads begin to unwind.

But this arthropod product is not
only responsible for human clothing.

It's shaped our culture
for over a thousand years.

The transport of silk
from Asia towards Europe

led to the establishment of
the famed Silk Road around 200 BC.

This 4,000-mile trade route

forged relationships between
different and diverse cultures.

And was pivotal in the development
of the civilisations

in China, India, Europe and Arabia.

So silk has shaped human culture
and distribution,

but there's another arthropod
product that's valued so highly

humans will risk their life
trying to collect it.

The Himalayas, in Nepal.

These men are climbing 400 metres
up sheer cliffs

to steal from giant honey bees.

They're the largest honey bee
in the world

and their stings are notoriously
painful.

So what could make men
risk their lives in this way?

Honey!

These bees, like honey bees
the world over,

take nectar from the surrounding
flowers

and spit it into the cells
in the comb.

Enzymes in their saliva
break down the sugars

and water evaporates
until the condensed honey remains.

This honey will be the colonies'
sole source of food

during the colder winter months

and they'll give up their lives
to protect it.

So the honey gatherers will not only
have to deal with perilous heights,

but also with angry bees.

When the men finally reach the comb,

they must manoeuvre sticks

to work free a section of honey.

With little protection
against the stings,

they must work quickly before
being overcome by the bees venom.

The honeycomb is dropped
into a suspended basket

and then lowered to the ground.

They leave a large section
of the comb intact

so the colony can rebuild
its honey supplies.

Job complete, the men can descend
to enjoy their hard-won prize.

Honey's made up
of 80% natural sugars

and so, provides a vital
energy-rich food source

for these mountain dwellers.

So prized is this product

that the farming of arthropods
for their honey has now gone global.

Around 1.2 million tonnes of honey
is produced worldwide each year.

When you think that one little
bee in its entire lifetime

produces only about
a spoonful of honey,

that's a humbling amount of work

from our arthropod friends.

But honey isn't the only product
that bees provide us with.

Bees and their relatives

have a much more far reaching
and significant effect on us humans.

Without which, it's questionable
if humans would survive at all.

And to see what this is,

we must examine a wonderful process
happening all around us

and responsible for shaping
the world we live in.

The coastal cliffs of Sardinia,

in the Mediterranean,

are home to an unusual plant.

The dead horse arum.

It looks like a dead rotting animal

and has a smell to match.

This canny flower even raises
its temperature

by as much as 20 degrees
above the surrounding vegetation

to complete its disguise.

The smell is taken by the wind

and it's not long
before the arum is noticed.

These flies are hoping
they've found a carcass

on which to lay their eggs,

but, instead, they become trapped.

Inside the flower,

they brush against the female stigma

releasing any pollen
they're already carrying.

This flower is now pollinated.

Spines prevent the flies' escape
and they're trapped.

Overnight, when the flies
are inactive,

the spines wither and the male
pollen above them ripens

ensuring that, in the morning,

each exiting fly is coated with
pollen to take to the next flower.

This flower has invested everything

in the process of cross-pollination.

It's modified its appearance,

its smell, its temperature

and its internal barriers,

all to ensure the transfer
of pollen grains

from one plant to another.

And it's this process of pollination

that's the next key

to why the arthropods are pivotal
to human success

and to our very own food chain.

As much as 35% of all human food

is dependent on pollination
by arthropods.

Across the world, the value of crops
pollinated by insects

is over £120 billion a year.

Without them, we wouldn't have
apples, almonds, cherries, oranges,

tomatoes or squash
on our supermarket shelves.

84% of crop species grown in Europe

still depend on insect pollination.

Without insects,
our crops would flounder,

supermarket stocks would plummet

and life on Earth
would irreversibly suffer.

But to really understand our
relationship with the arthropods,

we need to examine their negative
effects as well as the positive.

The deserts of West Africa.

Moisture in the soil
and increased temperatures

provide the triggers
for a mass hatching.

Eggs that may have lain dormant
for 20 years hatch

and flightless locusts,
called hoppers emerge.

These hoppers follow the smell
of freshly sprouting grass.

After about 20 days of feasting,

they transform into winged adults
and form a swarm.

A swarm can cover an area
of 1,000 square miles

and can literally blot out the sun.

They eat their own body weight
in food each day.

En masse, they can get through
200,000 tonnes of crops,

enough to feed
half a billion people.

Many arthropods have the potential
to reach biblical proportions.

Their ability to reproduce quickly
and prolifically

means their numbers,
left unregulated,

can snowball out of control.

For us humans, that can present
a real problem.

And there's a parasite that's
utilised this breeding success

and today, it's the biggest cause
of human fatality on our planet.

It kills 3,000 people every day

and without arthropods,
it wouldn't exist.

Throughout history,

this relentless killer has claimed
more victims than any other disease.

It's killed more people than
both the world wars put together

and at least 40% of the world's
population are at risk.

The disease is carried
by the Anopheles mosquito

and it's called malaria.

But, really, this mosquito

is just a pawn in a parasite's game.

The parasite lives
by eating the red blood cells

of the victim it attacks.

When a mosquito bites
an infected person,

it sucks up the blood containing
the parasite into its gut.

The parasite multiplies...

..then, burrows into the mosquito's
saliva gland...

..where it's squirted into the blood

of the mosquito's next victim.

And so, the cycle continues.

But can we really blame
the mosquito?

It gains nothing
from carrying the parasite.

And, ironically, mosquitoes,

along with other arthropods,

might be the ultimate solution
to this deadly disease

in their ability
to regulate each other.

An example of this is played out

in a field in the South Downs.

These aphids are doing
what aphids do best -

multiplying.

They're breeding machines

and, by the end of a season,

a single aphid can have produced
over a billion descendants.

Each aphid uses their specialised
mouth parts

to suck out the plants' juices.

Left uncontrolled, they can
devastate a whole field of crops.

Luckily for farmers and gardeners,

there's a crack team of predators
on standby.

Firstly, the colourful
but ferocious ladybird.

One ladybird can eat over
5,000 aphids in a lifetime.

But working alone,
they'd have their work cut out

to keep up with the prolific
breeding of the aphids.

Luckily, they've got backup.

Money spiders parachute in from
surrounding fences and hedgerows.

The spiders spin delicate
but lethal orb webs

and wait for their prey to arrive.

When the bumbling ladybird
has had her fill,

her movements dislodge
further aphids

that drop into the silken traps
below.

This natural balance
of predators and prey

may seem only relevant
to gardeners and farmers,

but the global importance
of this natural biological control

is not to be underestimated.

Pest control services
provided by insects were valued

at over 60 billion dollars a year,
in the USA alone.

This is a service
we really can't afford to lose.

And the arthropod regulators
could potentially provide some hope

against the worst disease
the human race has ever faced.

There are plans for
a non-malaria-carrying mosquito

to be released to outcompete
the deadly malaria-carrying ones.

So we've seen how arthropods
provide us with food and products.

How they've shaped
our distribution and culture.

We've seen how pivotal they are
to our own food chain

and how their presence can regulate
pests and even fatal diseases.

But there's one final key
to how they influence our lives...

..one final offering
from the arthropods

that could shape the way we exist
and operate in years to come.

In this vast colony,

every army ant appears
to be following a master plan,

like tiny cogs in a huge machine.

They allocate resources depending
on environmental conditions.

If a rich food source is found,

workers will appear
to deal with the bounty.

They build organised highways
with no congestion.

They construct shelter
and a place to rear their young

using their own bodies.

They stage foraging raids

and vacate an area of forest
when food sources dwindle.

They're efficient,
responsive and smart.

Everything our human organisations
strive to be.

But this colony doesn't function

like any organisation we humans
are familiar with.

There's no central control,
no figure of authority.

The queen ant may have
her lofty title,

but plays no role in coordination.

And we're just starting to learn
how such efficiency is achieved.

Haulage companies and airports
are learning to operate like ants.

Abandoning pre-determined
master plans

and instead focusing on smaller,

smarter decisions.

And it's not just the ants
that we're learning from.

Bees are teaching us how to build
honeycomb-style structures

providing maximum strength
while using minimal materials.

Spiders are helping us design
crawling robots

for inspecting ship hulls

and nuclear reactors.

Butterflies hold the key
in their wings

to harnessing the sun's energy
more efficiently than ever before.

And termites, with their unpowered
air conditioning towers,

are inspiring architects.

It seems that arthropods
really do have a lot to teach us.

Arthropods have been pivotal
in shaping our culture

and distribution.

Without them, our food chains
would collapse

and pests would multiply
beyond control.

We humans would do well to remember

that arthropods could survive
perfectly well without us.

But life as we know it
could not continue without them.

Subtitles by Red Bee Media Ltd