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00:00Plants
00:26have a family tree stretching back nearly half a billion years.
00:35They have developed an extraordinary range of strategies to survive.
00:43This tree is a bristlecone pine.
00:45It's taken thousands of years to reach this size.
00:50It has seen empires rise and fall, kings, queens and presidents come and go, and may
00:56have seen the sun rise more than one and a half million times.
01:04Bristlecone pines are the oldest living things on earth.
01:17Bamboo is the fastest growing plant.
01:23It will be full grown 30 metres tall in just 90 days.
01:38Like animals, plants are constantly competing for food.
01:45Striving to produce offspring, and battling against predators.
02:00They will deceive, and in some cases, they will even hunt.
02:30We often don't notice such dramatic behaviour, because to our eyes it happens so slowly.
02:39But if time is compressed, and you shift perspective to the plant's point of view, their world
02:45comes spectacularly to life.
02:48The events in this woodland can build to a view of half a year in less than a minute.
03:16Like animals, plants need food and water.
03:47But what sets them apart, is their struggle for light.
04:10Plants must have light in order to grow, and will do anything to get as much as they
04:15need.
04:20The forest might appear to be the perfect place for plants to thrive, yet down here
04:27on the forest floor, is one of the hardest places imaginable for a young plant to begin
04:34its life.
04:37The canopy above is so thick, that only a little sunlight can filter through.
04:47For this sapling, too little light means death.
05:02The plants on the forest floor need not be passive.
05:12If the light won't come to them, they can go to the light.
05:23But they still have a problem.
05:26The light is 50 metres above them, so they must climb.
05:42It's much easier to use another plant as scaffolding.
05:55But they won't get very high, unless they can hold on tight.
06:05Like fingertips searching for a hold, this ivy's adhesive pads grip the bark.
06:13Instead of sticking to the trees, some climbers use sharp claws.
06:22The cat's claw creeper hooks its tendrils into the tiniest crevices and hauls itself
06:28to the top.
06:38With every metre it climbs, the light gets a little stronger, fuelling more growth.
06:49This tendril of a passionflower seems to flail aimlessly in mid-air, but in fact it's
06:55searching for an anchor point.
07:05Its tendril coils on itself, pulling the plant towards its support.
07:19In a matter of just days, these climbers make it to the canopy.
07:27Now with light in plentiful supply, these plants are able to flower.
07:37Other plants have a different strategy to find the light they need in the crowded forest.
07:46These are air plants.
07:48They grow on the upper branches of tall trees and spend their whole lives basking in the
07:53light.
07:56But growing 50 metres above the ground does have its drawbacks.
08:02Most plants get water and nutrients through their roots in the ground.
08:07For an air plant, with their roots planted in the treetops, this isn't an option.
08:14But they have a solution.
08:18First, the bare roots have an extraordinary ability to soak up water like blotting paper.
08:27The slightest rain or mist and they absorb every drop.
08:35They also have a way of gathering nutrients.
08:42The roots trap falling leaves, which eventually rot and provide the plants with their own
08:47personal supply of compost.
08:57Twenty thousand different plants, orchids, bromeliads and ferns, have taken up this remarkable
09:03lifestyle.
09:27For a plant to thrive it must not only get enough nutrients, but also the right balance
09:33of nutrients.
09:35The soil in this waterlogged bog is very poor quality, lacking in nitrogen.
09:43But these strange plants have an ingenious strategy.
09:49Their leaves are covered in tentacles, tipped with droplets of what appears to be morning
09:54dew.
09:59These droplets give the plant its name, the sun dew.
10:09They're sweet smelling and attractive to many insects, but they're also extremely sticky.
10:22Mosquitoes emerge in huge numbers from the boggy water and the sun dews are ready.
10:52The sun dew's tentacles are living flypaper.
11:12Struggling only makes matters worse.
11:18With each contact the plant tightens its grip.
11:29As more and more tentacles envelop the prey, the droplets spread across its body.
11:38Eventually the insect is smothered and drowns in sticky fluid.
11:45These enzymes break down the body into a nitrogen-rich meal, which is absorbed by the plant.
11:52Without animal tissues, this plant would not survive.
12:01But there's another carnivorous plant that's an even more sophisticated predator.
12:16The Venus flytrap.
12:26Like the sun dew, it makes itself very attractive, oozing nectar across the brim of each leaf.
12:46But any visiting insect had better watch out for these six tiny hairs.
13:04This fly has to tread carefully.
13:14If it strikes one hair, it can carry on feeding, but a timer has been set.
13:30A second strike in less than 20 seconds and the fly is doomed.
13:44An electrical impulse is triggered and the leaf snaps shut in just a fraction of a second.
13:52The tips lock together like prison bars.
14:04If the fly is very big or very small, it may just manage to escape.
14:10But most are trapped and die.
14:37Ten days later, the trap reopens.
14:44All that remains is a husk.
14:48The plant has finished its meal and resets itself for its next victim.
14:58But there is one time of year when the Venus flytrap needs some of the visiting insects
15:03to live.
15:05It needs their help to be pollinated.
15:10It sends up flowers on tall stems well away from the danger of the traps below.
15:30Here insects can feed safely on nectar.
15:35In return, they provide a vital service, carrying pollen from flower to flower.
15:46But the truce is only temporary.
15:50When pollination is over, it's back to business as usual.
16:04Eighty percent of plant species on Earth have flowers.
16:10Flowers have just one role, to enable the plant to produce offspring.
16:15Colour, perfume, nectar and shape all act to make a flower irresistible.
16:25Sunflowers grow to face the rising sun.
16:29The warmth of the rays speeds the production of nectar, and this lures pollinators.
16:38One after another, hundreds of individual florets produce pollen-covered stamens.
16:56Like most flowers, sunflowers establish a close relationship with animals in order to
17:02ensure their reproduction.
17:10As these bees busily feed on nectar, they unwittingly brush against the stamens, collecting
17:15pollen, and then carry it from flower to flower.
17:24The sunflower is fertilised.
17:33In the sun-drenched fields of southern France, the flowering season is a long one.
17:39But not all plants have this luxury.
17:44Cradle Mountain in Tasmania is blasted by bitter Antarctic winds.
17:53To reproduce, the richier honeybush must flower.
17:58But the delicate parts of the flowers risk being damaged by the cold.
18:05The plant appears to have an ingenious solution.
18:10The flower petals fuse together, forming an insulated protective case around its stamens.
18:17However, this creates another problem.
18:21The flower case is so well-sealed that, unfortunately, it also keeps out pollinating insects.
18:29During brief sunny spells, the flowers warm up and suddenly start producing nectar.
18:39This attracts a bird, the black curawan.
18:44It has the strength to rip open the flower's outer casing and gets its reward of nectar.
18:50But at the same time, it exposes the delicate stamens to waiting insects.
19:01With luck, there's enough time for pollination before the biting wind kills the flowers.
19:16For some plants, the relationship with their pollinators is not collaborative.
19:22It's war.
19:25Butterflies, and in such numbers, would seem to be perfect pollinators for any flower.
19:33The Sandhill milkweed blooms every spring in the sandy meadows of Florida.
19:40At times, it's flowering perfectly to match the arrival of monarch butterflies migrating here from Mexico.
19:49The monarchs search out milkweed plants, but they have something other than pollination on their minds.
19:56Rather than collect pollen, this female lays her eggs on the milkweed leaf.
20:06This is the only plant the caterpillars can eat.
20:18But the milkweed has a defense mechanism.
20:27As the caterpillar bites into a vein, a kind of latex swells out, engulfing it.
20:38If the caterpillar isn't quick, it will drown, or find its jaws glued together.
20:49The plant's defense is so effective that only one-third of the monarch caterpillars make it through the first day.
20:58But the caterpillars that survive grow in size and strength.
21:12And they go for the jugular.
21:16By carefully chewing through the main vein, the caterpillar drains the leaf of latex and cuts off its supply.
21:25The milkweed's leaf is now defenseless, and the caterpillar eats in safety before preparing to pupate into a butterfly.
21:40But after about ten days, it becomes clear why the plant has endured this onslaught.
21:49A newly hatched monarch simply can't resist the nectar-filled cups of the milkweed flowers.
21:56As it moves across the flower heads, its feet slide between grooves in the petals, where the flower's pollen sacks are waiting.
22:07As it flies off, the monarch's feet hook out the pollen and carry it to the next flower, and pollination is achieved.
22:17Although the milkweed has paid a heavy price, in the end it used the monarch to get its way.
22:27Here in Dominica, there's a plant that is so manipulative that it has enslaved its pollinator.
22:36The bright red structures of the heliconia are actually modified leaves.
22:44These are its flowers.
22:47They may be small, but they play a very important role, keeping nectar well guarded at the very bottom of their long stems.
22:55The purple-throated carib hummingbird, with its long, curved beak, is the only bird capable of reaching this energy-rich food.
23:05But cleverly, the heliconia rations the amount of nectar it produces to force the hummingbird into returning to the flower time and time again.
23:20Every time it makes a visit, it picks up more pollen on its beak and feathers.
23:32The hummingbird is like an addict. Not only does it never stray, but it will aggressively defend the flowers from thieves.
23:41The plant is the master in this relationship.
23:47To ensure it gets pollinated, heliconia has made the hummingbird its prisoner.
24:00The plant's problems don't end once it's been pollinated.
24:06Plants need to spread their seeds as far away as possible, otherwise the adults will be in direct competition with their offspring.
24:16Here in South Africa, one flower achieves this by performing a remarkable trick.
24:29The plant waits dormant underground for more than a year.
24:36The first heavy rains for many months are the trigger the plant has been waiting for.
24:56Bronze vigia burst into flower.
25:07Their timing is perfect. These conditions are ideal for insects, too.
25:16The flowers enjoy a few days of frenzied pollination.
25:31But it's not long before the searing heat returns. The flowers start to wilt, shrivel and die.
25:45Bronze vigia now needs to disperse its seeds widely, yet the flowers still have their seeds trapped inside.
25:55But the flower isn't finished yet.
26:01There are strong winds that blow across this landscape.
26:05They snap the dry, dead stalks, sending each and every plant cartwheeling across the ground, casting seeds as it goes.
26:35With the heat threatening to dry them out, the seeds germination has to be immediate.
27:06Deep in the forests of Borneo, some plants also use the wind to disperse their seeds, but in a completely different way, by giving their seeds wings.
27:20Some are helicopters that twist and turn their way down to the ground.
27:38But there is one that has a design that enables it to travel greater distances than all the others.
27:47This is Alsomytra. Its football-sized pod is packed full of hundreds of extraordinary seeds.
27:58Each is an almost aerodynamically perfect glider that can be supported by even the slightest breeze.
28:10Its paper-thin, upswept wings allow it to travel hundreds of meters through the forest.
28:38As the seed hits the ground, the wings rot away and the seed starts to germinate.
28:58The new Alsomytra vine starts to grow up towards the canopy and into the light, well away from its parent.
29:10There are other ways to disperse seeds, and plants have evolved different tactics depending on where they live.
29:19In the desert of Arizona lives a master, the saguaro cactus.
29:28In the cool of the night, the cacti open their radiant flowers.
29:43They're soon visited by nectar-feeding bats, and as the bats move from cactus to cactus, they pollinate them.
30:12Each flower only lasts a night, but over three weeks each cactus will produce more than 200 flowers.
30:28Every pollinated flower immediately begins to form a fruit at its base, packed with thousands of seeds.
30:50The mature saguaro cacti are superbly adapted to survive out in the intense heat of the Sonoran desert.
30:59But their seeds are delicate and must find shade or they will scorch to death before they germinate.
31:06The seeds are covered with succulent sweet flesh, a meal that all sorts of desert creatures find irresistible.
31:17White-winged doves are among the first to reach the ripening fruit.
31:23The seeds survive in the birds' stomachs and will be carried many miles before being deposited in their droppings, their own little packet of fertilizer.
31:36But the cactus doesn't just rely on birds. Fallen fruit provides a bonanza for creatures on the ground.
31:47Foraging ants quickly gather seeds and flesh. That's if a tortoise doesn't get there first.
31:57The greater range of animals the cactus can get to eat its fruit, the more likely the seeds within will be carried to the perfect place to germinate.
32:06The ants carry the seeds underground into their nests, often excavated among the roots of trees.
32:16The tortoise, too, will head for shade. It spends much of its day cooling off under trees, where it's sure to leave undigested seeds in its dung.
32:30Now the seeds wait for the rains to come.
32:46Of the 14 million or so seeds a cactus produces in its lifetime, the chances are that only one will develop into a plant that outlives its parent.
32:58If it was lucky enough to find shade, a seed will still take ten years to become a five centimetre tall cactus.
33:08To reach the size of its parents, possibly ten metres, will take at least a hundred years.
33:19Plants can survive in the most unlikely and inhospitable places on earth.
33:26Here on Socotra, a remote island in the Arabian Sea, the dry season is brutal.
33:33But this strange tree has a strategy to survive it.
33:43The dragon's blood tree.
33:50The key to their success lies in their bizarre shape.
33:55They live on the mountaintops where there's little soil, but there are critical compensations.
34:04Occasional morning mists sweep across the high ground.
34:17The mist condenses on the skyward pointing waxy leaves.
34:23The droplets run down to the centre of the trunk and down to its roots.
34:34Water is so precious that the tree cannot afford to waste any.
34:43Drops that do escape and fall to the ground are not totally lost.
34:49The tree's huge, densely packed crown acts as a parasol.
34:57It shades the ground so effectively it allows time for the water to seep into the sand.
35:08And it also shades the network of trees.
35:13And it also shades the network of roots that lie just under the surface.
35:21Another plant shares this parched desert, but survives in a very different way.
35:30The desert rose.
35:33In really harsh conditions, it jettisons its leaves to minimise water loss.
35:43Strangely, it chooses this time to flower.
35:48Its bulbous trunk is like a barrel that stores water all year round.
35:57It's so hardy it can grow out of bare rock.
36:05It might seem that conditions can't get much tougher for a plant than here.
36:13But for some, the conditions are even harsher.
36:21Six hours ago, here on the coast of Australia, this tree was high and dry on a sandy beach.
36:28For almost all plants, saltwater is lethal,
36:32so submersion of this tree's roots by the tide twice a day should kill it.
36:43Yet this red mangrove is flourishing.
36:53The retreating tide reveals the key to surviving the sea's assault.
37:01The mangrove's roots are covered in warty growths.
37:06The growths surround pores that take in oxygen from the air
37:10when the roots are above water.
37:17But the pores become useful in a quite different way when they're submerged again.
37:28They allow water into the plant, but filter out 99% of the salt as it passes through.
37:35Any salt that gets in is pumped into a few sacrificial leaves that turn yellow and are discarded.
37:50Plants can not only cope with being poisoned, parched and scorched,
37:55but they can also survive being frozen.
37:58In the world's northern forests, the changing of the seasons creates its own challenges.
38:15As summer moves to autumn, plants prepare themselves for the toughest time of their lives.
38:22Broadleaf trees unveil what seems to us a colourful spectacle.
38:27But for these plants, it's the beginning of a series of urgent and drastic survival strategies
38:33to cope with the coming cold.
38:37They begin by pulling all the water and nutrients within the plant
38:41to ensure that it can survive the cold.
38:44The last rays of useful sunlight are channelled into making a sugary antifreeze
38:49that will protect the body of the tree.
38:56The green pigment, chlorophyll, disappears, leaving purples, reds, oranges and yellows.
39:04The leaves are then placed in a container,
39:08The green pigment, chlorophyll, disappears, leaving purples, reds, oranges and yellows.
39:16Finally, the leaves die and the trees discard them.
39:28As temperatures drop below freezing, the plants of broadleaf forests settle down to hibernate until spring.
39:39Pine trees can survive much colder conditions.
39:45They have antifreeze in the leaves themselves that means that they can keep them all winter.
39:53The needle-like leaves also have a thick, waxy coating
39:57that leaves can be used to protect them from the cold.
40:01The winters here are long and hard.
40:06The trees have to survive temperatures of down to minus 40 centigrade for five months.
40:22The trees have to survive temperatures of down to minus 40 centigrade for five months.
40:32Woah!
40:37That's cool!
40:42Apparently, warm air heals them well,
40:45and the tree is still strong enough to survive a Winter with this condition.
40:51The trees have to live all the way up through winter
40:55to hit Probopet's Garden's Meadows twice a year in order to get its huge sauce of leaves.
41:01But one pine tree is capable of surviving even harsher conditions.
41:21These pines live at the limit of life, above 3,000 metres in the mountains of Western
41:28America.
41:31Almost continuous freezing temperatures and savage winds make life so tough that these
41:37bristlecones only manage to grow for six weeks of the year.
41:45Everything is about conserving energy.
41:48They hardly ever shed their needles, which can last more than 30 years.
41:55After centuries of being blasted by storms, a full-grown tree still survives with only
42:00a strip of bark a few inches wide.
42:08These trees live life at such a slow pace that they can reach great age.
42:14Some are over 5,000 years old.
42:20It's been said of the bristlecones that to live here is to take a very long time to die.
42:35As the northern spring approaches, the warming temperatures and increased day length release
42:40the land from winter.
42:48Plants that have lay in dormant begin to grow again.
42:59Plants have overwintered, buried in the mud at the bottom of this frozen lake.
43:14The retreating ice allows the water to warm and this white water lily to flourish for
43:20another season.
43:38And as all the trees come out of their winter rest, the vivid green of new leaves returns
43:44to the land.
44:07From the frozen north to the southern deserts, the spring bloom symbolizes the success of
44:12plants in surviving against the odds.
44:42But the most successful type of flowering plant is one that makes up 20% of all plant
44:48life on the planet, grass.
44:55There are 10,000 different species.
45:04Today they form the diet of many thousands of different animals.
45:13And a few grasses, particularly rich in nutrients, have developed a relationship with one animal
45:21and together the two have changed the world.
45:35Ten thousand years ago, we humans started to cultivate rice in order to harvest its
45:41food rich seeds.
45:49Now half of the world's population depends on it.
46:03But there is one other grass that has spread even further across the planet due to its
46:08relationship with humans, wheat.
46:17Wheat underpinned the development of western civilization.
46:31Today it covers more of the land than any other kind of plant.
46:44Plants have been residents on land longer than animals and have had nearly half a billion
46:49years to evolve.
46:54During that time they've diversified into countless forms and have colonized every habitat.
47:10As well as collaborating with animals, plants are sometimes their masters, exploiting them
47:16to their own advantage.
47:30Plants capture energy from the sun and all life on land, directly or indirectly, depends
47:37on them.
47:39So ultimately, plants fuel the diversity of life on earth.
47:55To see the behavior of plants as they struggle to survive presented a unique challenge.
48:07The plants team had to employ many techniques including time lapse and high speed photography.
48:19They filmed in jungles, deserts, swamps and plains, but they also spent many hours shooting
48:24in a converted barn just outside Exeter.
48:39All under the watchful eye of green fingered cameraman Tim Shepard.
48:49Filming plants in time lapse takes so long and is so susceptible to changes in light
48:53levels and weather conditions that some key sequences had to be filmed in this studio.
49:06In time lapse a camera takes a series of pictures over an extended period of time, so when played
49:12back the action appears speeded up.
49:16These sunflowers actually take three days to open, but are seen opening in a matter
49:21of seconds.
49:26The most complex time lapse the team attempted showed an entire growing season in an English
49:34woodland in one continuous shot, a shot that took two years to create.
49:51As the producer, Neil Lucas, leads Tim and Mick Conair, the graphic designer, out to
49:56the location he explains his idea.
50:07It will be a tracking shot through the wood with plants growing, flowers blooming and
50:12the woodland coming to life over the course of a year.
50:17We're condensing that one year down into less than a minute, we're going to have to have
50:20them all coming out at the same time and that's going to be multiple passes isn't it?
50:24How long does a foxglove take to grow?
50:26Well if we start just before the buds are about to open and you've got the whole long
50:30spike from top to bottom that's probably about three weeks.
50:34So even if you wanted to you couldn't shoot the plants actually here because I mean three
50:38weeks the weather's going to change, you've got the day and night and also just leaving
50:42the equipment here running, it's not feasible is it?
50:46You just have to imagine the changes that would happen here in three weeks and if that
50:50was all joined together and one frame the plant might be there and you take a shot of
50:56it an hour later and if the wind's blowing it's over here somewhere and then you join
50:59those two shots together.
51:01So what we've got to do is not only have we got to produce a move that is exactly the
51:06same repeatable move, a track that can be built exactly the same again in a studio,
51:12build exact models of every object in here so we can put plants in the right places and
51:17then time everything so they grow just as the camera happens to be pointing at them.
51:22The scale of the challenge is dawning on them.
51:25Months of planning lie ahead.
51:30The following spring the team head back to the wood.
51:33With no road access, manpower is the only way to get the tonnes of equipment into position.
51:47Everyone's wondering how this will turn out, including the locals.
52:17That's pulled it, hang on, that's pulled it terribly.
52:32Oh, what's that?
52:36No, it's pulled this wheel round.
52:41Two days of building, levelling, test runs and even a few minor disasters and finally
52:48the track is ready to run.
52:50OK, that's just, that's pretty close, if you move your, can you see that little bit
52:56of lichen?
52:57Go to 8,900.
53:02Accuracy is paramount.
53:04Yeah, I mean whatever we shoot in the studio it's got to match this landscape exactly
53:10so unless we know precisely where everything is relative to the camera there's no way
53:14of placing the plants in the studio in the right place.
53:18So we have to measure the hell out of it.
53:20Oh, bloody hell, it's spot on, look at that.
53:24So, 250, OK.
53:35Shot by shot and step by step, the camera inches its way back up the 30-metre track.
53:41Well, that's working.
53:46This is only the background shot, there is still a huge amount of other filming to be
53:50done.
53:51The track has to be rebuilt exactly as it is on location back in the studio, a task
54:00that will take weeks to get right.
54:26Using the detailed measurements taken in the wood, the position, size and shape of
54:30every structure has to be matched precisely.
54:34What point?
54:37Thirty-five.
54:39Thirty-five, yeah.
54:42The slightest discrepancy will put the team back to square one.
54:50Chicanoir and polystyrene form the rocks and trees of the woodland.
54:55Blue screen is used to cover every inch of the set to allow the original shot to be mapped
55:01on later in graphics.
55:04Once built and with the plants placed in their exact locations, filming can start.
55:10The stars of the show finally make an appearance.
55:33Timing is everything.
55:35With each plant taking up to three weeks to flower, there's only one chance of getting
55:40it right.
56:05A year later, and thankfully, so far, all had gone to plan.
56:17The final stage is to bring all the pieces together seamlessly, a challenging task for
56:22any graphic designer.
56:24We've got things overlapping that wouldn't necessarily grow at the same time, but all
56:29the growth of each individual plant is absolutely accurate.
56:31It's exactly what they would do.
56:32We've just seen it in a short space of time.
56:35That big rock in the foreground at the end of the shot that we wanted to try and get
56:38stuff climbing on, well, that's worked really, really well.
56:43This is the bramble pass here.
56:45We had to measure it so carefully so we knew exactly where these things were, how round
56:49they were, how deep they were from the camera.
56:52And then when we take the blue out of that, you can see that the plants start to sit into
56:57the shot exactly where we wanted them to be.
56:59The plants disappearing from behind the tree, crawling on the top of the rock.
57:02That's fantastic.
57:03So here they go.
57:04And if I switch those off, you can see how just how neatly they slot into the shot.
57:08It's amazing.
57:09If we play it, you can see that everything's sticking in pretty well.
57:16Ninety-six layers, fifteen tracks, and two years later, the shot is finally complete.
57:27A sixty-second shot that proved to be one of the most complex ever attempted in natural
57:34history filmmaking.