Plants Behaving Badly (2014) s00e01 Episode Script
Murder and Mayhem
Once the world seemed full of strange natural wonders.
Griffins, dragons, unicorns, human headed beasts.
But few more stranger, then mysterious plants that ate people.
In the 19th century explorers described the ya-te-veo-tree from Madagascar.
They said it had tentacles like great green serpents with the savage tenacity of anacondas.
Of course ya-te-veo tree was only Victorian fiction, but like all good fiction it contained the germ of truth.
When Victorian naturalist explored the slopes of Mount Kinabalu in Borneo, they found something just as bizarre.
Plants bearing huge pitches.
And one of these contained the partially digested body of the rat.
The discovery caused a sensation, it fared the imagination of the greatest Victorian naturalist, Charles Darwin.
Through painstaking experiments he showed that many kinds of plants trapped and killed insects and then digested their bodies.
And they did this with methods as macabre as any dreamed up in the Victorian fiction.
PLANTS BEHAVING BADLY Murder and Mayhem To be carnivorous plants must catch and kill prey and they've evolved three ways of doing this.
Many work like flypaper, covered in sticky blobs to simply glue insects to the leaves.
Others have leaves shaped into pitches.
The pitches are full of liquid, which drowns and digests trapped insects.
Some of these plants have evolved traps of elaborate design.
The third method snap-traps, like old-fashioned mousetraps they snap shot on their prey.
When first discovered, these plants caused up row.
Do plants really catch and kill insects? A specimen was sent to the greatest botanist of the time.
Swedish botanist Carl Linnaeus thought it was an abomination.
Blasphemy, it went against the way God had ordered the world.
The Linnaeus created the system of classifying all living things that we still use today.
But he flatly refused to believe, that plants could be carnivores.
More than a century later Charles Darwin would prove him wrong.
He cultivated lots of carnivorous plants for his detailed experiments.
But he worked mostly on a little plant called sundew or drosera.
Darwin is most famous for explaining how new species originate.
But was so fascinated by these extraordinary plants that he said: âI care more about drosera than the origin of all the species in the worldâ.
The sundew is one of the sticky flypaper traps it gets its name from the tiny droplets of sticky liquid a kind of mucus on the end of stalks on its leaves.
Insects get stuck in this glue but at the time most people thought this was just an accident.
Darwin showed it was far more sinister than this.
These results both astounded and frightened him.
He put different substances on the leaves.
Milk, meat, paper, stone, even urine and recorded the plants reactions.
Milk caused the tentacles the fold over.
So did meat and urine.
But the plant didn't react to stone or paper.
Darwin showed that any substance containing nitrogen triggered a reaction.
He also found that the plants absorb these nutrients through its leaves.
It was a real carnivore like an animal.
But why have some plants turn carnivorous? Most of them live in places like this; bogs, swamps or marshes with soils are poor in nutrients like nitrogen.
Yet thereâs plenty of nitrogen here.
Itâs just walking around on six legs.
All the plant has to do is catch and kill bugs and it has plenty of fertiliser.
Just as Darwin saw, the sundew leaf reacts, when an insect gets stuck.
Over an half an hour or so the closest tentacles curled towards, a struggling insect gluing it more firmly.
Then the leaf folds right over the victim.
This holds the prey against the glands on the leaf that release chemicals to dissolve and digests the insect.
On seeing this Darwin wrote by Jove: âI sometimes think drosera is a disguised animalâ.
And in a way he was right.
In the swamps of Florida sundew is compete with other predators, with animals, for prey.
In places the ground is carpeted by pink sundews.
For most of the time there was no shortage of pray.
The sundews have plenty to eat.
But the plants have competition.
A wolf spider.
The spider builds a network of threads over the forest floor.
Anything walking on the web sends vibrations back to the spider hiding in a borrow at itâs centre.
The attack is lightning fast.
Sticky leaves provide all the nutrients this plants need to survive in wet forests and swamps.
But one plant has taken this further.
In the wild it only lives in small pattern of wet pine forest in North Carolina.
The Venus flytrap.
It evolved from the sticky tribal of sundew.
That slow curl of the sundewâs leaf is transformed into reaction so quick it can trap an insect.
Darwin was sent specimens whom you grew in his greenhouse to study in detail.
On close examination he saw that as well as spines around the edge of the leaves there were three fine hairs on the surface of each lobe.
He assumed they were triggers to close the leaf.
To find out he touched one likely but this didn't always far the trap.
But touching a second hair the trap always fared immediately.
Thereâs a good reason for this.
Firing the trap needs energy.
In the wild they live where it rains hard and often.
The last thing the plant needs is for the trap to fire when hit by nothing more than a raindrop.
If true hairs must be touched its less likely that the trap far by accident.
To spring the trap two of the hairs must be triggered within 20 seconds of each other.
The bug triggers the first hair.
Now the time bomb is ticking.
Just one more touch there.
And the trap snapshot.
Insects have fast reactions but the flytrap is even faster.
Slowing down the action 80 times shows the trap closing in around a third of the second.
The spines along the leaf edge slam closed like a prison gate.
But the gate isn't tightly closed.
Not yet.
And there is also a good reason for this.
The trigger hairs are sensitive enough to be triggered by even small insects.
Too small to make a decent meal for a growing flytrap.
But the gaps in the prison bars are wide enough for a small insect to escape.
And over the next few days with nothing to keep touching the hairs the trap is reset.
But more substantial meals are logged in and this struggling continues to stimulate the leaf hairs.
Over a few hours the sides of the trap squeezed together and selves on the inside release chemicals to kill and digest the insect.
It's easy to see why Darwin called this the most wonderful plant in the world.
The familiar flytrap has a lesser-known relative, an aquatic flytrap.
The waterwheel plant.
It gets its name from the spoke-like arrangement of branches, but paddles on this waterwheel are lethal traps.
Each trap is fringed with sensitive trigger hairs.
The traps are only a few millimetres long and work just like the flytrap.
But the waterwheel plant targets tiny creatures like seed shrimps and copepods.
Touch the fringe of hairs and the trap fires nearly as quickly as a Venus flytrap.
Even more amazing because this trap operates in water, which is much denser than air.
Caught this copepod will be slowly digested.
Darwin studies of sticky traps and snap traps prove that these plants were true carnivores.
But there is a third way to trap insects and Darwin was less sure about these The pitfall traps of pitcher plants.
He thought they might be carnivorous but we know now that they include some of the most elaborate and sophisticated traps of all.
Pitchers evolved separately several times.
In the America.
In the Australia and in Southeast Asia.
They are all beautiful but it's a deadly beauty.
Hiding fiendish devices to attract and kill the unwary.
Such design seemed too perfect for Darwin.
Could something so complex really evolve by natural selection? He need not worried.
The answer lies in the swamp forests of tropical America.
The trees here are aliening with bromeliads relatives of the pineapple.
Many growers epiphytes, clinging to the branches and trunks of trees high off the ground, where they bathed in sunlight.
But with the roots dangling so high in the air they can't absorb water and nutrients from the soil, like normal plants.
Instead the leaves form a well at the centre of the plant, which fills with water when it rains.
The well also catches leaves falling from the trees so the plant can absorb all the water and food it needs from its own private reservoir or not so private.
Many creatures see bromeliads wells as miniature ponds.
In South America poison dart frogs search from plant to plant looking for a well not yet claimed by anyone else.
A safe place to rear tadpoles.
But some bromeliads are not so welcoming.
Like most bromeliads Brocchinia has a central well deep in the heart of the plant.
But this one is acid and full of digestive enzymes.
Its leaves are coated in wax making them slippery as ice.
Ants exploring these leaves can't get a grip, slipping and sliding towards the deadly pit where there digested and turned into plant food.
From such simple beginnings natural selection has created more elaborated traps.
Several of the most elegant are hidden in remote areas of swampy pine forest in the southeast of the United States.
The sarracenia pitchers.
Stewart McPherson is a botanist and explorer who is discovered many new species of pitcher plants.
He is tramped and squelched through miles of the swamps to find some amazing places.
This is the North American pitcher plant of the sarracenia.
They produce this tall upright pitches and attract insects by having honey sweet nectar.
And as they trying get out of them they slip inside.
The prey then forced straight down to the bottom of the trap.
They can't escape from that.
They simply can't climb out of the inside pitcher.
So it dies and then the plant secretes enzymes and acids and breaks up the bodies of those trapped animals.
This is the yellow pitcher but this particular swamps not all of them live up to their name.
This species in particular is incredibly variable.
Every population pretty much as a bit different but as many different varieties is one over here, which is red with a yellow lid.
You see these red veins and patterns.
This advertises the trap to its insect pray that is what attracts it.
And there is another one.
And this is the third one within just a few metres is pure blood red.
This really stands out from all the other surrounding plants as the perfect advertising deadly trap.
Beeds of tempting sweet nectar standout on the underside of the lip, which is also covered in fine downward pointing hairs, to make it hard for an insect to keep itâs footing.
The tall conspicuous pitches advertise the nectar drawing insects, as would any bright flower.
Theyâre so busy gorging themselves on the nectar they don't notice that it's getting harder to hang on.
The slippery sides of the pitcher mean there's no escape as a plant secretes digestive enzymes to slowly dissolve its victim.
The meal more than repays the costs of making all that sweet nectar.
But sometimes the effort is wasted.
The sweet droplets are stolen by swallowtail butterflies- far too big to fall into the trap.
And many pitches have a resident green lynx spider waiting to snatch smaller prey before they caught by the plant.
There are eight or so different kinds of saraccenia pitches growing mostly in the warm and humid south-east corner of the United States.
But this the purple pitcher goes all the way up into Canada.
The purple pitcher is unusual for another reason.
It doesnât produce enzymes to digest its pray.
Yet it still a carnivore.
It's lid produces nectar and is clothed in downward pointing hairs.
It's just as lethal and efficient as itâs relatives.
But like Roridula the purple pitcher relies on help to digest itâs pray.
Trapped insects drown and sink to the bottom where the snakelike larvae of a mosquito called Metriocnemus chew and shred the bodies releasing small particles into the water.
Floating above Metriocnemus are other mosquitosâ larvae wyeomyia.
These have mouthparts like brushes that create strong currents of water drawing in the small particles.
Both mosquitoes release their waste products into the water full of nutrients that the plant can absorb.
The purple pitcher is a unique habitat.
This kind of mosquito larva is only found inside these pitchers.
All North American pitcher plants live in wet places and sometimes that can be a problem.
Heavy storms are common here during the summer.
The parrot headed pitcher has a lid that forms a hood, covering the pitcher and stopping it filling up with rain.
But it lives in swampy hollows that often flood during downpours.
Its hood can't stop it being completely submerged.
But this doesn't mean it can't catch prey.
The hood creates a narrow entrance hall leading to tube lined with backward pointing hairs.
This pitcher works like a lobster pot in miniature.
There are no miniature lobsters here.
But there are tadpoles.
They graze on the surface of the pitcher but if they enter into the trap they can't back out.
The only way is onward to the bottom of the pitcher.
There are relatives of the sarracenia pitches elsewhere in the New World.
The largest variety is found in South America.
But to find them means climbing to the tops of vast blocks of ancient sandstone rising thousands of metres into the air above the jungles of Venezuela, Brazil and Guyana.
These isolated mountains are called tepuis a local word meaning âhouse of the Godsâ.
The tops of the tepuis are flat plateaus lost worlds high above the rainforest.
This is the only home of the sun pitchers.
Like all American pitches the trap is formed from a leaf.
In some pitches it looks like a flat leaf that simply rolled up to form the tube with seem still visible down the front.
But that doesn't mean that they are primitive.
They're quite the opposite.
They're beautifully adapted to life on these isolated mountaintops.
Moisture from the rainforest below is forced to rise by the sheer cliffs, releasing torrents of rain.
It rains nearly all the time up here giving the sun pitches a problem.
Unlikely North American relatives they don't have a lid to act as an umbrella.
So the pitches could overflow with water washing out valuable nutrients or making the pitcher so heavy it falls over.
But even as it rains the water level in the pitcher starts to drop.
The scene down the pitcher hides a small hole that drains water into a flat channel.
A drain pipe that carries water safely away to the base of the pitcher, keeping the water level just right.
The rainforests of Southeast Asia, home to the Nephentes pitches.
These plants growers find often tens of metres long trailing through the trees.
And the exquisite pitches grow from tendrils of the tips of their leafs.
There are around a 130 different kinds of the Nephentes pitches.
The diversity is amazing.
The most spectacular lives here on the slopes of Mount Kinabalu in Borneo.
A mountain climb many times by Stuart MacPherson in his search for new kinds of carnivorous plants.
This is Nephentes rajah.
Itâs actually the largest of all the pitcher plants in the world.
This is juvenile trap and can get that twice this size, and this species is known only from four small sites like this one.
Each site consists of maybe 300, 400, 500 plants so in total the entire world population is just about 2000 plants, and thatâs it globally.
Like the North American pitches these elaborate structures had evolved to trap and digest insects.
But in the last few years botanists have realised that Nephentes pitches are more than just predators.
This is the fanged pitcher, name for two snakelike fangs projecting down beneath the lid.
The fangs produce nectar to attract insects, which then slide off the pointed chips into the pitches digestive juices.
But there are also insects living in the pitcher a species of ants.
They have no problem walking on the slippery walls and help themselves to the plants pray.
They even swim in the pitcherâs fluid to steal food.
But there are no such things as a free lunch.
The ants congregate beneath rim and every now and then emerged to clean the rim of the pitcher, which keeps it slippery.
So the ants helped the pitcher catch food and later they get their own share.
In return the pitcher provides the ants for the home a hollow loop in its stem.
The ants chew an entrance hall and build their nests inside.
Only one species of ant lives with fang pitcher like this.
All other insects are merely dinner.
And other pitches to form partnerships just as close but with a more sinister outcome.
The white band pitcher named for an unusual band white hairs just below the rim.
Chen Lee is a botanist who knows these rich forests intimately.
Heâs discovered several new kinds of pitcher plants and now knows how this one collects its food.
This is Nepenthes albomarginata.
It is one the most unusual pitcher plants.
Itâs got very distinctive white band in the edge of peristome here which is unique in the entire genus.
And only recently did we find out that this white band is attracted to termites.
They feed on this band and in so doing a lot of them falling inside the pitcher so it is the termite specialist.
Itâs very difficult to observe in the wild.
You see pitches that have missing band and youâll find termites inside but actually witnessing them doing it yet be quite lucky.
One reason is that the pitcher specialises on just one kind of termite, which is mostly active after dark.
Millions of termites fan out from their nest across the forest floor moving in flowing columns that never seem to end.
If a scout finds white band pitcher it recruits other workers and they call up the side of the pitcher.
The white hairs are irresistible and they gorge themselves.
As more termites swarm onto the pitcher the first arrivals get pushed towards the slippery rim of the pitcher.
Itâs not long before the inevitable happens.
Itâs purely chance if termites find a white band pitcher so not all pitchers have a successful night.
But itâs not hard to spot the ones that have feasted well.
Look at this.
Here is one right here missing the white band actually.
So this is definitely have some termite inside.
Letâs have a look.
Look at that.
There is hundreds of drowned termites inside.
These look like theyâve had been already partially digested by the plant so hardly meal for this pitcher plant.
Some pitcher plants are given up being carnivores.
Theyâve turned vegetarian.
This is the flask-shaped pitcher it has a tiny lid bent back to expose the flask to the forest canopy above.
The gaping mouths of the flask have evolved, to catch leaves and twigs that drop from the trees above.
Inside the pitcher a whole varied community of creatures helps break down the leaves, releasing nutrients for the plant to absorb.
Different kinds of mosquito larvae even tadpoles.
These belong to the matang narrow-mouthed frog a species, which prefers to breed in the sanctuary of these private ponds.
But it's not entirely safe here.
This is Toxorhynchites, another mosquito larvae.
But this one is predator.
It devours other mosquito larvae.
A miniature world hidden inside the pitcher.
Far from just being carnivorous nepenthes pitches are formed all kinds of complex relationships with animals and the most astonishing has only just been discovered.
Whilst working in the rainforest on Mount Kinabalu in Borneo Chen realised that the biggest of all pitches the giant rajah pitcher had some unusual visitors.
What makes this pitcher plant unusual is not just that it's carnivorous but it also attracts mammals to visit the pitcher.
There is nectar secreted on the under surface of the lid here.
And you can see all these glands on the end of surface here and they constantly secreting nectar, actually both, day and night.
And very recently the first research was done on the species.
And that is where we got footage and photographs proving that these animals are actually visiting the pitcher.
The creature Chen saw was the mountain tree shrew.
They balance on the rim of the pitcher and reach up to lick of the nectar.
Each tree shrew knows where all the pitches are in its territory and visit each one in turn.
But what's in it for the plant? As it feeds the tree shrew urinates and defecates into the pitcher.
And these nutrients supplement for the plants normal diet of insects.
Tree shrews are only active during the day.
But nightfall doesn't mean an end to the rajah pitcher supply of fertiliser.
After dark it continues to produce nectar.
Which now feeds the summit rat.
Just like the tree shrew it straddles the pitcher to feed and drops it's scats into the bowl.
These pitches are enormous and summit rats are small.
If it slips it will end up trapped inside the pitcher where it will become plants next meal.
Though as Stuart MacPherson explains that's not the plant's intention.
The truth of the matter is so that it's not quite as dramatic as that.
The plants didn't evolve to catch vertebras.
They evolved trap and kill insects.
It just under certain circumstances the same bite also attracts larger play.
A many rats by accident they just simply slip inside.
They are very biggest of pitches.
The traps are so big that vertebras like rodents and mammals they just canât climb up so drown and digested within the plant.
In some cases you can even find skeletons within the pitches.
So that original discovery of a dead rat on the slopes of Mount Kinabalu was probably an accident.
But a happy one at least for our understanding of carnivorous plants.
It caused a sensation and inspired Charles Darwin to reveal the remarkable lives of these plants.
Times have hardly changed.
Recently Stewart made a similar discovery.
A rat trapped in a giant pitcher.
He took this photograph and it cause just as much of a sensation.
I was really amaze surprised because this image went viral.
It went into newspapers all around the globe and on websites.
And really get to show that people are really fascinated by these plants, capturing and killing animals just like back in Victorian days, when first reported discovery was made.
It seems our fascination with these strange plants is just as great now as it was when they were first discovered.
And there are certainly even more surprises hidden in this mountains.
I climb about 200 or so mountains in search of new species.
And found about dozen or so in last few years.
But there are literally hundreds and hundreds more mountains still to be explored.
There must be dozens and dozens more species, awaiting discovery.
It is also these incredibly complex relationships with different animals and other organisms that we are only beginning to understand.
There is incredible chapter of new exploration.
The Victorian accounts of man-eating plants were entertaining stories.
By the discoverers of the last few years have shown that in the world of carnivorous plants truth is much stranger than fiction.
Griffins, dragons, unicorns, human headed beasts.
But few more stranger, then mysterious plants that ate people.
In the 19th century explorers described the ya-te-veo-tree from Madagascar.
They said it had tentacles like great green serpents with the savage tenacity of anacondas.
Of course ya-te-veo tree was only Victorian fiction, but like all good fiction it contained the germ of truth.
When Victorian naturalist explored the slopes of Mount Kinabalu in Borneo, they found something just as bizarre.
Plants bearing huge pitches.
And one of these contained the partially digested body of the rat.
The discovery caused a sensation, it fared the imagination of the greatest Victorian naturalist, Charles Darwin.
Through painstaking experiments he showed that many kinds of plants trapped and killed insects and then digested their bodies.
And they did this with methods as macabre as any dreamed up in the Victorian fiction.
PLANTS BEHAVING BADLY Murder and Mayhem To be carnivorous plants must catch and kill prey and they've evolved three ways of doing this.
Many work like flypaper, covered in sticky blobs to simply glue insects to the leaves.
Others have leaves shaped into pitches.
The pitches are full of liquid, which drowns and digests trapped insects.
Some of these plants have evolved traps of elaborate design.
The third method snap-traps, like old-fashioned mousetraps they snap shot on their prey.
When first discovered, these plants caused up row.
Do plants really catch and kill insects? A specimen was sent to the greatest botanist of the time.
Swedish botanist Carl Linnaeus thought it was an abomination.
Blasphemy, it went against the way God had ordered the world.
The Linnaeus created the system of classifying all living things that we still use today.
But he flatly refused to believe, that plants could be carnivores.
More than a century later Charles Darwin would prove him wrong.
He cultivated lots of carnivorous plants for his detailed experiments.
But he worked mostly on a little plant called sundew or drosera.
Darwin is most famous for explaining how new species originate.
But was so fascinated by these extraordinary plants that he said: âI care more about drosera than the origin of all the species in the worldâ.
The sundew is one of the sticky flypaper traps it gets its name from the tiny droplets of sticky liquid a kind of mucus on the end of stalks on its leaves.
Insects get stuck in this glue but at the time most people thought this was just an accident.
Darwin showed it was far more sinister than this.
These results both astounded and frightened him.
He put different substances on the leaves.
Milk, meat, paper, stone, even urine and recorded the plants reactions.
Milk caused the tentacles the fold over.
So did meat and urine.
But the plant didn't react to stone or paper.
Darwin showed that any substance containing nitrogen triggered a reaction.
He also found that the plants absorb these nutrients through its leaves.
It was a real carnivore like an animal.
But why have some plants turn carnivorous? Most of them live in places like this; bogs, swamps or marshes with soils are poor in nutrients like nitrogen.
Yet thereâs plenty of nitrogen here.
Itâs just walking around on six legs.
All the plant has to do is catch and kill bugs and it has plenty of fertiliser.
Just as Darwin saw, the sundew leaf reacts, when an insect gets stuck.
Over an half an hour or so the closest tentacles curled towards, a struggling insect gluing it more firmly.
Then the leaf folds right over the victim.
This holds the prey against the glands on the leaf that release chemicals to dissolve and digests the insect.
On seeing this Darwin wrote by Jove: âI sometimes think drosera is a disguised animalâ.
And in a way he was right.
In the swamps of Florida sundew is compete with other predators, with animals, for prey.
In places the ground is carpeted by pink sundews.
For most of the time there was no shortage of pray.
The sundews have plenty to eat.
But the plants have competition.
A wolf spider.
The spider builds a network of threads over the forest floor.
Anything walking on the web sends vibrations back to the spider hiding in a borrow at itâs centre.
The attack is lightning fast.
Sticky leaves provide all the nutrients this plants need to survive in wet forests and swamps.
But one plant has taken this further.
In the wild it only lives in small pattern of wet pine forest in North Carolina.
The Venus flytrap.
It evolved from the sticky tribal of sundew.
That slow curl of the sundewâs leaf is transformed into reaction so quick it can trap an insect.
Darwin was sent specimens whom you grew in his greenhouse to study in detail.
On close examination he saw that as well as spines around the edge of the leaves there were three fine hairs on the surface of each lobe.
He assumed they were triggers to close the leaf.
To find out he touched one likely but this didn't always far the trap.
But touching a second hair the trap always fared immediately.
Thereâs a good reason for this.
Firing the trap needs energy.
In the wild they live where it rains hard and often.
The last thing the plant needs is for the trap to fire when hit by nothing more than a raindrop.
If true hairs must be touched its less likely that the trap far by accident.
To spring the trap two of the hairs must be triggered within 20 seconds of each other.
The bug triggers the first hair.
Now the time bomb is ticking.
Just one more touch there.
And the trap snapshot.
Insects have fast reactions but the flytrap is even faster.
Slowing down the action 80 times shows the trap closing in around a third of the second.
The spines along the leaf edge slam closed like a prison gate.
But the gate isn't tightly closed.
Not yet.
And there is also a good reason for this.
The trigger hairs are sensitive enough to be triggered by even small insects.
Too small to make a decent meal for a growing flytrap.
But the gaps in the prison bars are wide enough for a small insect to escape.
And over the next few days with nothing to keep touching the hairs the trap is reset.
But more substantial meals are logged in and this struggling continues to stimulate the leaf hairs.
Over a few hours the sides of the trap squeezed together and selves on the inside release chemicals to kill and digest the insect.
It's easy to see why Darwin called this the most wonderful plant in the world.
The familiar flytrap has a lesser-known relative, an aquatic flytrap.
The waterwheel plant.
It gets its name from the spoke-like arrangement of branches, but paddles on this waterwheel are lethal traps.
Each trap is fringed with sensitive trigger hairs.
The traps are only a few millimetres long and work just like the flytrap.
But the waterwheel plant targets tiny creatures like seed shrimps and copepods.
Touch the fringe of hairs and the trap fires nearly as quickly as a Venus flytrap.
Even more amazing because this trap operates in water, which is much denser than air.
Caught this copepod will be slowly digested.
Darwin studies of sticky traps and snap traps prove that these plants were true carnivores.
But there is a third way to trap insects and Darwin was less sure about these The pitfall traps of pitcher plants.
He thought they might be carnivorous but we know now that they include some of the most elaborate and sophisticated traps of all.
Pitchers evolved separately several times.
In the America.
In the Australia and in Southeast Asia.
They are all beautiful but it's a deadly beauty.
Hiding fiendish devices to attract and kill the unwary.
Such design seemed too perfect for Darwin.
Could something so complex really evolve by natural selection? He need not worried.
The answer lies in the swamp forests of tropical America.
The trees here are aliening with bromeliads relatives of the pineapple.
Many growers epiphytes, clinging to the branches and trunks of trees high off the ground, where they bathed in sunlight.
But with the roots dangling so high in the air they can't absorb water and nutrients from the soil, like normal plants.
Instead the leaves form a well at the centre of the plant, which fills with water when it rains.
The well also catches leaves falling from the trees so the plant can absorb all the water and food it needs from its own private reservoir or not so private.
Many creatures see bromeliads wells as miniature ponds.
In South America poison dart frogs search from plant to plant looking for a well not yet claimed by anyone else.
A safe place to rear tadpoles.
But some bromeliads are not so welcoming.
Like most bromeliads Brocchinia has a central well deep in the heart of the plant.
But this one is acid and full of digestive enzymes.
Its leaves are coated in wax making them slippery as ice.
Ants exploring these leaves can't get a grip, slipping and sliding towards the deadly pit where there digested and turned into plant food.
From such simple beginnings natural selection has created more elaborated traps.
Several of the most elegant are hidden in remote areas of swampy pine forest in the southeast of the United States.
The sarracenia pitchers.
Stewart McPherson is a botanist and explorer who is discovered many new species of pitcher plants.
He is tramped and squelched through miles of the swamps to find some amazing places.
This is the North American pitcher plant of the sarracenia.
They produce this tall upright pitches and attract insects by having honey sweet nectar.
And as they trying get out of them they slip inside.
The prey then forced straight down to the bottom of the trap.
They can't escape from that.
They simply can't climb out of the inside pitcher.
So it dies and then the plant secretes enzymes and acids and breaks up the bodies of those trapped animals.
This is the yellow pitcher but this particular swamps not all of them live up to their name.
This species in particular is incredibly variable.
Every population pretty much as a bit different but as many different varieties is one over here, which is red with a yellow lid.
You see these red veins and patterns.
This advertises the trap to its insect pray that is what attracts it.
And there is another one.
And this is the third one within just a few metres is pure blood red.
This really stands out from all the other surrounding plants as the perfect advertising deadly trap.
Beeds of tempting sweet nectar standout on the underside of the lip, which is also covered in fine downward pointing hairs, to make it hard for an insect to keep itâs footing.
The tall conspicuous pitches advertise the nectar drawing insects, as would any bright flower.
Theyâre so busy gorging themselves on the nectar they don't notice that it's getting harder to hang on.
The slippery sides of the pitcher mean there's no escape as a plant secretes digestive enzymes to slowly dissolve its victim.
The meal more than repays the costs of making all that sweet nectar.
But sometimes the effort is wasted.
The sweet droplets are stolen by swallowtail butterflies- far too big to fall into the trap.
And many pitches have a resident green lynx spider waiting to snatch smaller prey before they caught by the plant.
There are eight or so different kinds of saraccenia pitches growing mostly in the warm and humid south-east corner of the United States.
But this the purple pitcher goes all the way up into Canada.
The purple pitcher is unusual for another reason.
It doesnât produce enzymes to digest its pray.
Yet it still a carnivore.
It's lid produces nectar and is clothed in downward pointing hairs.
It's just as lethal and efficient as itâs relatives.
But like Roridula the purple pitcher relies on help to digest itâs pray.
Trapped insects drown and sink to the bottom where the snakelike larvae of a mosquito called Metriocnemus chew and shred the bodies releasing small particles into the water.
Floating above Metriocnemus are other mosquitosâ larvae wyeomyia.
These have mouthparts like brushes that create strong currents of water drawing in the small particles.
Both mosquitoes release their waste products into the water full of nutrients that the plant can absorb.
The purple pitcher is a unique habitat.
This kind of mosquito larva is only found inside these pitchers.
All North American pitcher plants live in wet places and sometimes that can be a problem.
Heavy storms are common here during the summer.
The parrot headed pitcher has a lid that forms a hood, covering the pitcher and stopping it filling up with rain.
But it lives in swampy hollows that often flood during downpours.
Its hood can't stop it being completely submerged.
But this doesn't mean it can't catch prey.
The hood creates a narrow entrance hall leading to tube lined with backward pointing hairs.
This pitcher works like a lobster pot in miniature.
There are no miniature lobsters here.
But there are tadpoles.
They graze on the surface of the pitcher but if they enter into the trap they can't back out.
The only way is onward to the bottom of the pitcher.
There are relatives of the sarracenia pitches elsewhere in the New World.
The largest variety is found in South America.
But to find them means climbing to the tops of vast blocks of ancient sandstone rising thousands of metres into the air above the jungles of Venezuela, Brazil and Guyana.
These isolated mountains are called tepuis a local word meaning âhouse of the Godsâ.
The tops of the tepuis are flat plateaus lost worlds high above the rainforest.
This is the only home of the sun pitchers.
Like all American pitches the trap is formed from a leaf.
In some pitches it looks like a flat leaf that simply rolled up to form the tube with seem still visible down the front.
But that doesn't mean that they are primitive.
They're quite the opposite.
They're beautifully adapted to life on these isolated mountaintops.
Moisture from the rainforest below is forced to rise by the sheer cliffs, releasing torrents of rain.
It rains nearly all the time up here giving the sun pitches a problem.
Unlikely North American relatives they don't have a lid to act as an umbrella.
So the pitches could overflow with water washing out valuable nutrients or making the pitcher so heavy it falls over.
But even as it rains the water level in the pitcher starts to drop.
The scene down the pitcher hides a small hole that drains water into a flat channel.
A drain pipe that carries water safely away to the base of the pitcher, keeping the water level just right.
The rainforests of Southeast Asia, home to the Nephentes pitches.
These plants growers find often tens of metres long trailing through the trees.
And the exquisite pitches grow from tendrils of the tips of their leafs.
There are around a 130 different kinds of the Nephentes pitches.
The diversity is amazing.
The most spectacular lives here on the slopes of Mount Kinabalu in Borneo.
A mountain climb many times by Stuart MacPherson in his search for new kinds of carnivorous plants.
This is Nephentes rajah.
Itâs actually the largest of all the pitcher plants in the world.
This is juvenile trap and can get that twice this size, and this species is known only from four small sites like this one.
Each site consists of maybe 300, 400, 500 plants so in total the entire world population is just about 2000 plants, and thatâs it globally.
Like the North American pitches these elaborate structures had evolved to trap and digest insects.
But in the last few years botanists have realised that Nephentes pitches are more than just predators.
This is the fanged pitcher, name for two snakelike fangs projecting down beneath the lid.
The fangs produce nectar to attract insects, which then slide off the pointed chips into the pitches digestive juices.
But there are also insects living in the pitcher a species of ants.
They have no problem walking on the slippery walls and help themselves to the plants pray.
They even swim in the pitcherâs fluid to steal food.
But there are no such things as a free lunch.
The ants congregate beneath rim and every now and then emerged to clean the rim of the pitcher, which keeps it slippery.
So the ants helped the pitcher catch food and later they get their own share.
In return the pitcher provides the ants for the home a hollow loop in its stem.
The ants chew an entrance hall and build their nests inside.
Only one species of ant lives with fang pitcher like this.
All other insects are merely dinner.
And other pitches to form partnerships just as close but with a more sinister outcome.
The white band pitcher named for an unusual band white hairs just below the rim.
Chen Lee is a botanist who knows these rich forests intimately.
Heâs discovered several new kinds of pitcher plants and now knows how this one collects its food.
This is Nepenthes albomarginata.
It is one the most unusual pitcher plants.
Itâs got very distinctive white band in the edge of peristome here which is unique in the entire genus.
And only recently did we find out that this white band is attracted to termites.
They feed on this band and in so doing a lot of them falling inside the pitcher so it is the termite specialist.
Itâs very difficult to observe in the wild.
You see pitches that have missing band and youâll find termites inside but actually witnessing them doing it yet be quite lucky.
One reason is that the pitcher specialises on just one kind of termite, which is mostly active after dark.
Millions of termites fan out from their nest across the forest floor moving in flowing columns that never seem to end.
If a scout finds white band pitcher it recruits other workers and they call up the side of the pitcher.
The white hairs are irresistible and they gorge themselves.
As more termites swarm onto the pitcher the first arrivals get pushed towards the slippery rim of the pitcher.
Itâs not long before the inevitable happens.
Itâs purely chance if termites find a white band pitcher so not all pitchers have a successful night.
But itâs not hard to spot the ones that have feasted well.
Look at this.
Here is one right here missing the white band actually.
So this is definitely have some termite inside.
Letâs have a look.
Look at that.
There is hundreds of drowned termites inside.
These look like theyâve had been already partially digested by the plant so hardly meal for this pitcher plant.
Some pitcher plants are given up being carnivores.
Theyâve turned vegetarian.
This is the flask-shaped pitcher it has a tiny lid bent back to expose the flask to the forest canopy above.
The gaping mouths of the flask have evolved, to catch leaves and twigs that drop from the trees above.
Inside the pitcher a whole varied community of creatures helps break down the leaves, releasing nutrients for the plant to absorb.
Different kinds of mosquito larvae even tadpoles.
These belong to the matang narrow-mouthed frog a species, which prefers to breed in the sanctuary of these private ponds.
But it's not entirely safe here.
This is Toxorhynchites, another mosquito larvae.
But this one is predator.
It devours other mosquito larvae.
A miniature world hidden inside the pitcher.
Far from just being carnivorous nepenthes pitches are formed all kinds of complex relationships with animals and the most astonishing has only just been discovered.
Whilst working in the rainforest on Mount Kinabalu in Borneo Chen realised that the biggest of all pitches the giant rajah pitcher had some unusual visitors.
What makes this pitcher plant unusual is not just that it's carnivorous but it also attracts mammals to visit the pitcher.
There is nectar secreted on the under surface of the lid here.
And you can see all these glands on the end of surface here and they constantly secreting nectar, actually both, day and night.
And very recently the first research was done on the species.
And that is where we got footage and photographs proving that these animals are actually visiting the pitcher.
The creature Chen saw was the mountain tree shrew.
They balance on the rim of the pitcher and reach up to lick of the nectar.
Each tree shrew knows where all the pitches are in its territory and visit each one in turn.
But what's in it for the plant? As it feeds the tree shrew urinates and defecates into the pitcher.
And these nutrients supplement for the plants normal diet of insects.
Tree shrews are only active during the day.
But nightfall doesn't mean an end to the rajah pitcher supply of fertiliser.
After dark it continues to produce nectar.
Which now feeds the summit rat.
Just like the tree shrew it straddles the pitcher to feed and drops it's scats into the bowl.
These pitches are enormous and summit rats are small.
If it slips it will end up trapped inside the pitcher where it will become plants next meal.
Though as Stuart MacPherson explains that's not the plant's intention.
The truth of the matter is so that it's not quite as dramatic as that.
The plants didn't evolve to catch vertebras.
They evolved trap and kill insects.
It just under certain circumstances the same bite also attracts larger play.
A many rats by accident they just simply slip inside.
They are very biggest of pitches.
The traps are so big that vertebras like rodents and mammals they just canât climb up so drown and digested within the plant.
In some cases you can even find skeletons within the pitches.
So that original discovery of a dead rat on the slopes of Mount Kinabalu was probably an accident.
But a happy one at least for our understanding of carnivorous plants.
It caused a sensation and inspired Charles Darwin to reveal the remarkable lives of these plants.
Times have hardly changed.
Recently Stewart made a similar discovery.
A rat trapped in a giant pitcher.
He took this photograph and it cause just as much of a sensation.
I was really amaze surprised because this image went viral.
It went into newspapers all around the globe and on websites.
And really get to show that people are really fascinated by these plants, capturing and killing animals just like back in Victorian days, when first reported discovery was made.
It seems our fascination with these strange plants is just as great now as it was when they were first discovered.
And there are certainly even more surprises hidden in this mountains.
I climb about 200 or so mountains in search of new species.
And found about dozen or so in last few years.
But there are literally hundreds and hundreds more mountains still to be explored.
There must be dozens and dozens more species, awaiting discovery.
It is also these incredibly complex relationships with different animals and other organisms that we are only beginning to understand.
There is incredible chapter of new exploration.
The Victorian accounts of man-eating plants were entertaining stories.
By the discoverers of the last few years have shown that in the world of carnivorous plants truth is much stranger than fiction.