Madeira: Island Ark Nature's Wonderlands: Islands of Evolution

Created by fire and titanic upheavals of the earth,

islands make up one sixth of the landmass of our planet.

They are lenses through which to study the complex workings

of evolution.

Tropical islands have been important in the understanding

of evolution ever since Charles Darwin visited the Galapagos

early in the 19th century.

We're going to visit three very different tropical islands

to see what THEY can tell us about evolution, even today.

Islands are natural laboratories.

Full of novel experiments in natural selection

and evolutionary wonders.

But there's much more to evolution than the survival of the fittest.

The phrase wasn't even in Darwin's first edition

of The Origin Of Species.

'I'm exploring other major influences - geology, geography...'

Hello!

'..isolation and time.'

-You found this?

-Yes.

-Giants' bones.

I'll be charting the life cycle of islands -

from birth and colonisation to the burst of evolutionary creativity

that often accompanies maturity...

They take the leaves so delicately.

..and what eventually happens when an island grows old

and nears its end.

You can almost feel this unforgiving rock return ultimately to sea level.

Places of extinction as well as creation.

Our story will reveal evolution in action...

We just discovered new species of the mouse lemurs.

-So mouse lemurs are still actively evolving?

-Yeah.

..and how life generates abundance, even from a blank slate.

Islands are the ideal place to understand

the rules that govern evolution.

So far in this series, I've been to Hawaii,

and seen how a freshly born volcanic island is formed

and colonised by life, and how species adapt to new environments.

Then, in Madagascar's rainforest,

I investigated how a large island matures,

and the extraordinary diversity of habitats,

plants and animals that long periods of time engender.

In this third and final episode, I travel to Madeira -

an island far into the geological ageing process,

and one that is a refuge for species that are elsewhere extinct.

It's easy to be seduced by Madeira as a holiday paradise.

The land of flowers.

In fact, it's something of an ark,

but it's an ark where time has not stood still.

Where evolution is still in action.

It's a wonderful place to understand the processes underlying

the origin of species.

500 miles from the southern tip of Europe

and 360 from the west coast of Africa,

Madeira is the largest of a group of ancient volcanic islands.

And at its heart is the laurisilva.

Millions of years ago,

this forest struck root in Madeira's rich volcanic soil.

And while the biting cold of the last ice age wiped it out

almost everywhere in Europe,

fragments of special forest survived on this subtropical island.

Today this remote and ancient forest can be reached

following the traditional man-made water channels known as levadas.

Built over centuries, there are more than 1,000 miles of them,

lined by invasive agapanthus brought here by the Portuguese settlers.

The levadas irrigate crops far below.

But they also provide gateways.

On the south side of the mountain, the laurisilva is mixed with

troublesome foreign weeds, but on the other side of the mountain

there is a secret Eden,

and I can reach it through an underground tunnel.

Ooooh...

It's a bit narrow here. Bloody hell.

'The levada tunnels are a treacherous walk for the unwary,

'but others have made a home here.'

I've just found, in the most unlikely place, in the dark,

a spider.

Maybe it's one of those special dark-adapted cave spiders.

After several hundred feet, I spot distant daylight.

Oh, wow.

It's like suddenly going back three million years.

A designated UNESCO World Heritage site,

the laurisilva is a living relic of Europe

as it was millions of years ago.

Guided by palaeobotanist Carlos A Gois Marques,

who probably knows more about the island's ancient plants

than anyone else,

I first examine the tree from which the forest derives its name.

Laurisilva means forest of laurels.

Well, now, that is a fine-looking...old tree.

-And which one is it?

-Well, it's called the stink laurel because

of its wood, it's very smelly. It smells. It stinks, really.

And do we know why that might be?

Most probably it could be like a defence for the tree.

I gather this has a history, though, this particular tree.

Yes, this tree once lived in Europe and became extinct

because of climate change, but they are still living here in Madeira.

So it really is true

-that we have walked into a sort of time warp here.

-Exactly.

These tall and ancient laurel species are not alone.

Other strange and special endemic plants evolved alongside them.

Even turning into giants.

This is the common or garden spurge, you probably know,

but look what it does in the laurisilva.

It's evolved into a tree.

Turning into a tree, evolving what is called woodiness,

is an evolutionary strategy

also adopted by this relative of the dandelion.

From seeds carried by bird or by wind,

such plants had to compete for light

with the evergreen laurisilva forest,

and one strategy available to them was to become giants themselves.

Oh, yes!

This is a foxglove.

It's a foxglove that's turned into a tree.

The flowers are yellow, not pink, like our native foxgloves,

but it's a real tree hanging out of a cliff.

Ha! Well, let's see if we can get one. Yes, we can.

Look at that.

It's a pretty...

I suppose a raceme is the technical term for it.

A bundle of flowers all put together in a terminal bunch,

and very attractive too.

In the laurisilva forest, size matters.

In the absence of grazing animals, defences such as prickles

and spines became redundant.

A case of "use it or lose it".

It's a special bramble.

Yes. It's a bramble that only grows in laurisilva.

And has it got some particular features?

Oh, yes. As you can see it, it has big leaves.

Very large leaves. Yes.

And also we have fewer prickles on it.

Not many spines, and is that because of not much browsing pressure?

Yeah, most probably this plant evolved in the...in a place

where there are no mammals to eat the leaves away.

So it doesn't need much defence.

And also, it has big blackberries.

Big blackberries. That sounds good.

Yes. Unfortunately you are not on the season of the blackberries.

Back in his lab in the University of Funchal, Carlos shows me how long

it has taken some of the newer forest plants to evolve into giants.

So, as you can see, you have here an example of a fossil bramble.

-A fossil bramble? Can I look down the...?

-Yeah, of course.

Oh, yeah. Three leaflets.

These are the tips of the bramble itself.

It was found in the north part of the island

and it's 1.5 million years old.

So we're looking back all that time at what you might say is

an ancestor of what we have on the island today.

-Exactly.

-So over the last million-and-a-half years,

-this has become bigger.

-Exactly.

And is now a part of the laurisilva flora that is

-so special to the island.

-Exactly.

1.5 million years was time enough to this bramble

to evolve into something new.

And deposits like this are extremely rare

because we are in a volcanic island.

-So you must have been really pleased when you found it.

-Oh, yeah, very.

Very pleased. It's so rare to find something like this.

In one-and-a-half million years, the leaves of this fossil have

grown to be five times larger than when it first arrived.

A similar growth spurt has accompanied

the evolution of another Madeiran giant.

Spiders can be carried far and wide by the wind, and wolf spiders,

like this nocturnal hunter,

have possibly been here for millions of years.

But on the nearby Desertas archipelago -

a group of small islands off the coast of Madeira -

they have evolved into an arachnophobe's nightmare.

The island's only residents are two park rangers.

One of them, Isamberto Silva, has been ferried back to Madeira

by the Portuguese navy, with special permission to show me one.

Since she can give a very nasty bite, I'm taking no chances.

I'm about to meet Europe's largest spider,

Hogna ingens, which lives on a small island just off Madeira.

And I am looking forward to the prospect in a grisly kind of way.

Hogna ingens is a wolf spider.

Cousin of the familiar arachnids found in nearly all houses.

The world's fastest spiders can move at 50cm a second.

And as you can see, Hogna ingens isn't far behind.

Every island in this group of islands has an endemic species,

and they're all a little scary and rather large.

A wonderful example of island gigantism.

Will he come on my glove, do you think?

'According to Mediterranean tradition, it was the bite

'of the wolf spider that gave rise

'to the frenzied dance of the tarantella.

'So when European explorers found even larger spiders

'in the New World, they called them tarantellas, or tarantulas.'

Well, I hope she's comfortable.

I'm a little uncomfortable. HE CHUCKLES

Well, I think, charming though it is, I don't want to move too fast,

so maybe I can hand it back to Daddy.

And have you been bitten by this spider?

Yes. They have a poison.

They have a...

coagulation...

-Oh, I know, it breaks down the tissue and produces a big scar.

-Yes.

'Having collected spiders like this since he was a boy,

'Isamberto has built up immunity to their venom.

'But it's lethal to the small lizards it preys on.

'Moving from a diet dominated by insects to one including lizards

'no doubt helped nudge Hogna ingens to become larger.'

Giants are a common feature of island life,

but evolution does place limits on a spider's size.

Even with unlimited resources and no threat of predators,

there is still a ceiling on how big you can get.

Spiders - like insects or crustaceans - are arthropods.

That is, they have jointed legs.

They carry their skeleton on the outside,

so their legs, for example, are like tubes with the muscles inside.

This imposes a real limit on how large they can grow.

Surprisingly, it's not just gravity

which imposes limits on the size of arthropods.

Oxygen also has a crucial role to play.

Because they have their skeleton on the outside,

arthropods have to absorb oxygen, as it were, through the skin.

This too imposes severe limits on the size to which they can grow.

In some arthropods, there are little tubes inside the animal

that increase the surface area,

but even they can only operate up to a certain size.

As an arthropod gets bigger, the volume increases

disproportionately to the surface area.

In other words, once you get large,

it's harder and harder to get enough oxygen into the system.

Today, the biggest living arthropods are found in the oceans.

Water contains roughly 12% more oxygen than air,

and its buoyancy neutralises the limits gravity imposes on land,

which means that these spider crabs can grow legs six feet long

and weigh upwards of 40 pounds.

Nevertheless, in the past, terrestrial arthropods have

certainly grown much bigger than they do today.

300 million years ago,

the atmosphere was exceptionally rich in oxygen

and that allowed for giants to appear.

Dragonflies larger than any that have lived on earth.

Millipedes two metres long.

It must have been a rather wonderful, if bizarre, world.

Today the giants of the Madeiran archipelago live in a kind of ark.

Laurisilva forest was once found

all over the Mediterranean and North Africa.

What remains is just a fragment.

A time capsule isolated from the outside world whose inhabitants,

both large and small, have been spared from the predators

and competitors that might otherwise have led to their extinction.

If a special habitat persists, then so will the species adapted to it.

And nowhere proves this better

than the wonderful laurisilva forest in Madeira.

But the laurisilva isn't the only persistent habitat on Madeira.

Directly beneath it lies another ancient ark

of a very different kind.

This subterranean world was created by the island's last gasp

of volcanic activity nearly one million years ago.

I'm in a cave deep beneath the mountains of Madeira.

It's a special kind of cave. It's a lava tube.

And once it was flowing with red-hot liquid volcanic rock.

Hot basalt magma is extremely liquid and fluid. It flows very fast.

As it cools, though, it produces a crust on top

which actually seals the lava in,

so you could say that the basalt makes its own burial chamber.

And then eventually it drains out in the further edge of the eruption,

leaving behind the tube, but here you can see on the base

of the tube the last moments of the magma as it froze.

Like an island within an island, these lava tubes have been

isolated from the outside world for almost a million years.

And only a few creatures have evolved to survive in them.

But sightings are so rare,

I'll need to track one down in the island's capital, Funchal.

I'm told that in the nice, old natural history museum

here in Funchal, it is one of these denizens of the deep lava tubes

which I'm going to try and discover.

The museum is almost as difficult to navigate as the island's

labyrinthine lava tubes.

The object of my quest - a beetle as rare as the most precious gem.

So, which is the famous cave species in here? That one?

It's absolutely minute.

And it rejoices in the name of Thalassophilus pieperi,

which just goes to prove that the Latin name is in inverse proportion

to the size of the animal, but then, you know,

I'm not surprised it's small because after all, in a cave,

there's very little to eat and

it doesn't come along very often, so you might say of course it's small.

To survive stark subterranean environments, many insects shrink,

becoming dwarfs, which is exactly what this beetle has done.

But Madeira is home to other invertebrates whose size has

also been determined by their habitat.

This tiny snail is one of 180 different snail species.

It's become a dwarf because it's adapted to living

on the island's high peaks, where food is scarce.

In contrast, these much larger snails live close to sea level,

where there is food in abundance.

Its large size and hard shell also has a secondary benefit.

It acts as a deterrent against all but the largest birds.

Yet it is largely thanks to birds

that snails colonised Madeira in the first place.

Recent research suggests that up to 15% of snails can survive

passing through a bird's digestive system to emerge alive in droppings.

But oddly, Madeira has almost no native birds.

While Charles Darwin's finches in the Galapagos

evolved into many species,

here in Madeira there's another bird that bears the name of finch.

The Madeira chaffinch.

But it's tremendously similar to the European chaffinch

and is only recognised as a different subspecies.

In other words, it's almost the same thing.

'Hawaii's iconic honeycreeper birds are also finches.

'Yet on Hawaii,

'an island group younger than Madeira, honeycreeper are not only

'native but they have diversified into more than 50 endemic species.'

And each one of them has a specialist ecological niche to fill.

So why haven't the numerous birds of Madeira evolved

into endemic species?

The answer lies here in the natural history museum at Funchal.

People come to Madeira to watch birds,

and there are plenty of birds to be seen.

But walking around this collection, I noticed

that most of them are actually the same as those in Europe.

But why is that?

Birds of passage moving from Africa to northern Europe

pass through Madeira

and then most of the common European birds are also found on Madeira.

Probably because they island-hopped at an earlier stage.

There is a big difference, in fact,

how evolution has behaved on Madeira, compared with Hawaii.

Most of the ecological niches are actually occupied,

filled by European birds.

There's not so much opportunity

for evolution to generate its own novelties.

Unlike Hawaii, which is located 3,000 miles from the nearest

continent, Madeira is only 360 miles from Africa and 500 from Europe.

This proximity means its ecological niches are filled by regular

immigrations from the nearby continents.

One other species has moved into Madeira's ecological niches,

which has arrested the natural processes of evolution.

Homo sapiens.

Human development on the island has been a major

factor in its evolution for well over half a millennium.

In 1419, Captain Zarco,

in the service of Henry II of Portugal -

sometimes called Henry the Navigator -

set foot on Madeira for the first time.

Within a few years, huge swathes of its natural forest had been burned.

One fire is supposed to have burned for seven years.

Soon, sugar cane was being cultivated in vast areas.

It made the fortunes of many.

So with the dawn of the age of discovery for Portugal,

it was the end of the age of innocence for Madeira.

The loss of innocence that accompanies humankind's arrival and

settlement of any island was however not without its benefits to science.

It's a little-known fact

that Charles Darwin's The Origin Of Species

refers to Madeira more often than the Galapagos.

And that was because his close friend, the pioneering naturalist

Thomas Vernon Wollaston, spent many years studying endemic insects here.

In the year 1847 he named

and described many of the species that are peculiar to the island.

He was a friend of Darwin's, perhaps not so well-known,

made a huge contribution in providing the scientific name

still in use today for the insect fauna of this island,

and of course Wollaston realised that some of the species on Madeira

were different from those of anywhere else.

In other words, he recognised endemics.

Now, some of those endemics still survive.

This rather attractive speckled brown butterfly,

which you can still see flying in some of the highlands here.

But other species were not so fortunate.

And just to show how the island has been influenced by human arrival,

this large white butterfly is named after Wollaston himself.

And rather poignantly, it is extinct.

Pieris brassicae wollastoni wasn't the only insect Wollaston was

interested in studying.

His great passion was for naming endemic beetles.

He was particularly intrigued by the prevalence of flightlessness.

One of the things that happens with endemic speciation is that

particular characteristics are lost,

and one of the beetles in front of me,

which rejoices in the name of Meloe austrinus,

belongs to a family, most of which have good capacity for flight.

This particular beetle has become flightless.

It's an example of what you might term

the "use it or lose it" principle.

Why has it become flightless?

Well, it lives in the high part of the island,

where the wind hardly ever stops,

and actually it helps the beetle to stay more on the ground.

If it took to the air, it would

probably be blown away to some place it didn't like,

so this particular endemic species evolved

to cope with a very particular adaptive problem.

Wollaston noted that of the 550 beetle species

he was aware of in Madeira, 200 were flightless.

This and other evidence of island variation

proved invaluable to Darwin.

Even though Wollaston himself, as a conservative Christian,

could never bring himself to accept evolution.

Sadly, like Pieris brassicae wollastoni,

many of his beloved beetles became extinct

because of the spread of agriculture over Madeira.

The extent to which humans have transformed the island

is apparent everywhere.

Because 90% of the island is steep cliffs,

the airport is an engineering wonder, extends into the sea.

Even much of Funchal, the island's capital,

clings to the precarious slopes of a deep ravine.

The lower slopes are covered with rich volcanic soil.

Any crop can grow here. There are bananas, there are grapes,

a profusion of vegetables,

and there's practically no room for wildlife of any kind.

But there is one creature that is more than happy to cohabit

with the human population.

The Madeiran wall lizard.

Since the arrival of these lizards,

like humans, they have spread to every corner of the island...

and can be found in all shapes and sizes.

'As Dr Jose Jesus from the University of Funchal shows me.'

They have an extremely high colour diversity.

For example, the colour of the belly is very...

They're lively as well.

Oh, yeah.

For example, you've got here one that is greenish.

That brilliant greenish colour.

Yes, and then you have got this one that is darker.

But dorsal colour pattern...

-The back.

-..is important. We call this reticulatus.

-Reticulatus.

-Yes.

Whereas this guy...

Now, in some cases,

-those kind of differences would be a species difference.

-Yes.

In many other lizards.

Yes, but here it's only one species.

'All these lizards are the SAME species.'

Madeiran wall lizards found in cultivated areas are usually

green and brown, indicating their livery is adapted for camouflage.

But it's not always the case.

Darker lizards have been found by the coast, possibly to

protect their skin against the more violent UV radiation from the sun.

Though they are one species,

they have several different approaches to reproduction.

I understand that lizards are quite often territorial animals.

Does this play out here on Madeira as well?

Here sometimes when territorial species arrive to the islands,

they have different answers.

Some become non-territorial species.

Ah, this is the sneak strategy, isn't it?

So it's rather like a man who sneaks in through the back door

while the husband is away.

Yes, and it's curious that they have higher reproductive success.

The Madeiran wall lizard arrived

nearly three million years ago from Africa.

Probably on a natural raft of vegetation.

Since then, the island has become a sort of lizard Shangri-La.

Although there's only one species,

they are different in some ways from lizards that don't live on islands.

Yes, some of these animals, they can reach 16 years.

16 years.

Yes, that is more or less

four times more than most of mainland species of this size.

So they're the same size but they are four times older, if you like.

-Yes.

-So that's equivalent to us landing on a desert island

and finding human beings aged maybe 300 years.

-Yes. Can you imagine?

-I can imagine it!

Unlike mainland species,

island lizards can't count on rich resources

to sustain a high birth-rate.

The Madeiran wall lizard has elected instead to produce fewer young

and consequently needs to live longer to keep up the population.

Island life has served to extend their lifespan.

But islands have a lifespan of their own.

'To try and grasp the vast geological time periods

'entailed in the volcanic island's life cycle, I head out to sea.'

Madeira and the other much-smaller islands surrounding it

first began to rise from the sea floor 18 million years ago.

It took a further ten million years for eruptions to raise

the volcanic pile 4,000 metres to sea level,

and another seven for Madeira to reach high into the skies.

It's an extraordinary thought that these magnificent cliffs

more than 1,800 feet tall, built up layer by layer by volcanic eruption,

are just the tip of an enormous iceberg.

The cliffs carry on down, as it were, beneath where I'm standing.

Today, only 4% of Madeira is above the water line.

The remaining 96% forms

one of the largest sea mountains in the North Atlantic.

This giant geological formation has created a rich deepwater habitat

that attracts aquatic mammals from all over the world.

The dolphins and their close cousins, the whales, are living here

and enjoying life so much because of the geology of Madeira.

The rock that plunges so deeply down to the abyssal floor

brings up cold nutrient-rich currents from the depths

that nourish shoals of fish,

which, of course, provide their favourite food.

Back on land, I discover how weathering helps erosion.

Madeira was built up from a whole series of explosive eruptions,

and the basalt rock seems so hard and so unforgiving, but even hard,

unforgiving rock weathers away over geological time,

and basalt weathers in a most particular style,

known as onion-skin weathering.

Here's a largely unweathered centre

to a concentrically more-weathered area,

and you can almost feel this unforgiving rock turning into soil.

Indeed these plants are living on it.

So you can begin to understand how even a high structure

like an island like Madeira can return ultimately to sea level.

Madeira is geological proof that what goes up...

must go down...

Wow.

It feels completely out of control

but actually I'm sure they know exactly what they are doing.

That's one way to go round a corner.

That just shows how steep the...

..sides of a volcanic pile are, when lava flows

a pile on top of one another, as we've been

sliding down on this extraordinary journey.

'As Madeira's volcanism has come to an end,

'so the island has begun slowly sinking under the combined force

'of its own massive weight and the erosive effects of wind and rain.'

So I suppose for every...foot or so

we go down here, we're talking about another thousand years of erosion.

And... Oh, I nearly met the wall then.

Ah...

And here we are. Phew.

But that's far from the end of Madeira's story.

After all, 96% of the island is beneath the sea.

I can see some of the unusual species found in these waters

in the fish market in Funchal.

These espada... obviously deepwater fish

because they've got great eyes

to make use of whatever light there is at that depth,

and the needle-like teeth don't leave much doubt

that this is a serious predator.

So it's quite an ugly critter,

but actually tastes really rather wonderful.

Which gives me an idea.

-Hello. Good afternoon.

-Good afternoon.

-Please.

-Thank you.

Ah. Thank you very much.

Thank you.

Roast sweet pepper too. Quite nice.

Well, this is the famous espada,

a black scabbard fish which I've seen in the market,

and I can't help wondering

whether its taste lives up to its reputation.

As indeed it does.

No, it's really delicious.

It's not quite as firm as cod,

but just as kind of succulent on the tongue.

It's a really delicious fish.

And the Madeirans don't want to eat anything else. It's hugely popular.

And it's served here with a banana,

which, of course, is one of the great crops of Madeira.

So we've got a large part of Madeiran history on my plate here.

Actually, the banana's pretty good too.

Rather less edible examples

of Madeira's deepwater evolutionary oddities

are kept in the Marine Biological Station of Funchal.

The station was originally established more than 70 years ago

to study deep-sea fish, particularly sharks and rays,

and as a window onto the marine habitat surrounding Madeira.

Among the most-prized specimens in their collection is this monster.

It's an anglerfish.

The largest specimen ever found,

and, in a way, the strangest imaginable example

of how in evolution, if you don't use it, you lose it.

In this case, the male of the species.

It has dwindled to virtually nothing.

You can recognise this as an anglerfish

by the strange little fishing rod contraption at the top,

which has a lure to attract its prey.

It's an extraordinary and rather bizarre looking fish,

and it's the one in which the male of the species has become

more reduced than in almost any other organism.

In fact...this tiny little appendage hanging off the corner here

is the male.

It's been reduced to little more than a tiny stump.

And its function, really, is just to produce sperm.

So in some ways, this fish is the ultimate feminist icon.

Today, one of the most important aspects of the centre's work

is monitoring the effects of human pressure

on the ecosystem around Madeira.

Here, often swimming beneath the oblivious tourists above,

the divers scout for local species like these large starfish.

Spiny and a little intimidating,

there are 700 known species of sea urchins.

Sea urchins and starfish can be good indicators

of the health of the sea.

Changes in their abundance can be correlated with pollution levels.

Although these cloudy waters near the shore would normally

carry some sediment, washed here by soil erosion,

in recent years the concentrations have increased.

And numbers of endemic invertebrates are declining

due to the changing nature of the coastal waters.

Two of the divers, Pedro Neves and Claudio Correa Ribiero,

both marine biologists, have brought back samples.

So what have we found today?

Here we have two sea urchins and two starfishes.

And we normally use these animals for exhibitions.

Especially with the kids, so that they can feel how it feels to touch.

So how often do you go out on these dives?

Lately we have been diving three, four week...

four times in a week, to survey new spots

along south coast of Madeira also,

trying to see if there's a new habitat

with a different type of species.

And what particular changes have you noticed

since you've been doing these kind of studies?

Right now, we have big thick layer of sediment just on top of all

the rocks, and that prevents marine organisms from growing as abundantly

as they used to, so that's one cause for concern right now.

But one group of specialist filter feeders seems to find

the marine conditions of Madeira exactly to their taste.

Joao Canning Clode

is leading a team investigating animals called bryozoans.

These minute creatures, some only a millimetre across, band together

forming large colonies which can abound on parts of the ocean floor.

Not surprisingly, they are easy to catch.

We attach this settling plate to a brick and basically, we suspend

this in a marina or a harbour, and after a certain period of time -

usually it's three months -

we already have a pretty mature community of bryozoans.

Madeira has a wealth of endemic bryozoans,

but thanks to shipping containers, a huge influx of new invaders

are arriving from as far afield as Brazil.

And how do these introduced species arrive here in Madeira?

A cargo ship comes to Madeira.

It needs to discharge the water from another part of the world,

and discharges into Madeira waters.

And are they ever a problem, these new invasive species?

They can constitute harm for others, for other native communities,

but also they could impact what we humans are doing.

For example, they are... there is a bryozoans species

which is known as the spaghetti bryozoan.

It looks like spaghetti, and they can get attached

to propellers of boats, and this can constitute a problem.

So how many species are there here, if you count them up?

We are not 100% sure, but we believe hundreds.

Just in one family of bryozoans we get 140 species.

-Good Lord!

-We are getting new records for Madeira every two months

and I'm not exaggerating.

Just in this plate I can count seven different species.

Madeira's waters are no longer a persistent

and slow-changing habitat,

but one that is undergoing rapid environmental change.

This deepwater long-snouted lancetfish has a voracious appetite

and will eat almost anything.

'Because of this, the centre's director, Manuel Biscoito,

'conducts regular dissections of its stomach contents.

'What he finds inside is probably the best available

'record of how the undersea environment is changing,

'and whether deep-sea invasive species

'are entering Madeiran waters.'

It's a sort of a needlefish.

Another species, that lives in this mid-water...

-With a very obvious needle on the front.

-Absolutely.

That's the delicate shell of an argonaut. That's one I do know.

The female.

Ooh, is that...? That looks suspiciously like something human.

That is something human indeed.

Well, absolutely as you said, and it's an identifiable species too.

-It's plastic.

-It's got a barcode.

Well. It's a wrapping of some sort of product.

So the fish would have seen that

-floating down through the water...

-And mistaken it...

a jellyfish, for example, or other organisms of the plant. It must...

And we've got another piece.

Do you think it's the same wrapper or a different one?

It's probably the same.

I can't recognise the writing on there.

No, it seems Greek or Arab.

So we need a linguistic expert now!

The invasive species in this case is man-made.

What makes this find so disturbing is that the lancet hunts

at depths of over 200 metres,

and incidences of eating plastic have only appeared

in the last decade or so.

Well, that's an amazing inventory from one dissection

but it's only part of a really long-term series of data.

It is indeed. It started in 1945.

Have you got your books for that?

Yes, we actually have the original registers from there. Which we have.

Here are the original records,

and it says here "report on the contents...

"stomach content of the lancetfish."

-On March 1945, one of these had six argonauts.

-Like those.

Large argonauts, and some other cephalopods, what is here.

And it goes on and on and on, along the...

since 1945, up to now.

My handwriting, because in the meantime I arrive here...

I just pick up 2010.

April... August 17, and I say here, "Plastic debris...

-"and a piece of newspaper."

-HE CHUCKLES

Madeira is in just the right place, is it not,

to monitor global changes, perhaps due to climate change?

Absolutely. We are really in a privileged site to witness that

and monitor that change and we have been writing new records of fish.

Tropical species that are appearing here that we've not seen before

and we know, we are noticing that some fish that are more typical

from the colder, from the temperate areas, are just slowly vanishing.

All this proves to me,

the importance of a long-term vision for science.

Long-term research is very valuable.

It's very much known now as old-fashioned science.

Very hard to get finance for this,

but it is absolutely crucial to do this, to continue these efforts.

If we really want to understand what is happening

to our oceans and our planet.

Madeira's location on the borders between the temperate

and tropical zones of the Atlantic Ocean give it a uniquely global

overview on how climate change is impacting on marine evolution.

We can only hope that just as the Madeirans have learned

lessons from their past, so can the rest of us.

Because the deep blue waters that surround this tiny island

once ran red with the blood of whales and dolphins.

Within living memory, Madeira has turned from being

one of the most prolific whaling islands in the world

to one of the most popular for dolphin and whale watching.

It's a story we have also seen on the two other islands of our series.

That's a lovely view. A lovely view.

On Madagascar, we joined a small group of dedicated

conservationists struggling to preserve what remains

of the rainforest so many of the unique animals and plants depend on.

While on Hawaii, we witnessed the strenuous efforts being made

to save rare species after the devastating

effects of invasive diseases and new predators.

Here too we saw how modern science is trying to use pioneering

techniques to bring back species almost from beyond the grave.

Extinction on islands is ever present.

Here in the laboratory on Hawaii,

dedicated to saving their rare plants from extinction,

might be a good place to ponder what we should think

about the extinction of species on the planet as a whole.

Extinction is part of the history of life.

Always has been, always will be.

In fact, you could say you can't have evolution without extinction.

As we have seen throughout this series, islands beautifully

illustrate how many species can evolve from a single founder.

Yet many of those ancestors have themselves long since gone extinct.

What is unprecedented, though,

is the rate at which these species are now going extinct.

This probably hasn't happened...

well, since the extinction of the dinosaurs.

But islands are particularly vulnerable.

The introduction by humankind of lethal invasive species has swiftly

and profoundly transformed Hawaii's long-isolated fauna and flora.

While Madagascar's rainforest is threatened

by eucalyptus plantations

which encourage the slash and burn of native forest.

But these islands are the very place, as we've seen,

where we can understand how evolution works most clearly.

So to save a few plants on Hawaii, for example,

is not just to save a few pretty organisms,

but it's to save important evidence

for the very workings of evolution itself.

If islands are places where paradise has so often been lost,

they may also remain our best hope

for learning how paradise might be regained.

It's pretty adorable.