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AnimalsTranscript
00:00Thank you for listening.
00:41Thank you for listening.
01:21Thank you for listening.
02:22There are few places where it's more difficult to make a permanent home than a freshwater torrent like this one.
02:51Violent currents drip across the riverbed, scouring it clean.
03:03Ripping land plants from their margins and drowning them.
03:12How could any plant survive in a place like this?
03:28Yet even here, some do manage to, quite literally, hold on.
03:38They can grasp the bare rock with remarkable strength.
03:49This ability allows plants to thrive in these otherwise hostile environments.
04:00This is the Caño Cristales River in Colombia.
04:20These plants are red macarhenia, sometimes called the orchid of the falls.
04:37They cling to the riverbed not with their roots, but with their stems, glued to the rock surface by one
04:45of the most powerful adhesives in nature.
04:55The rock itself will break before these anchors lose their grip.
05:10These feathery filaments are their modified leaves, and they do what roots normally do.
05:17Gather the minerals and nutrients they need that are dissolved in the water.
05:28With such spectacular colors, it's hardly surprising that the Caño Cristales is sometimes called the most beautiful river on Earth.
05:45But being rooted to the spot is not always the best strategy for living in a water world.
05:54This is a water lettuce, and it has some remarkable adaptations.
06:02Its roots hang free, so it's not anchored to the ground.
06:09And its leaves are thick and spongy, and covered in fine hairs, so that the plant itself is more or
06:17less unsinkable.
06:27This combination of characteristics enable the water lettuce to do something that almost no land plant can do.
06:35It can travel.
06:40It is an ability that becomes invaluable when, during the wet season, flooded rivers become great highways, as they do
06:50here in South America.
06:57This is the largest inland water world on Earth, the Pantanal.
07:04For a few months every year, it provides water plants with ideal conditions.
07:12But all too soon, it becomes a battleground.
07:25Plants are racing to claim their space on the surface.
07:30The water lettuce rapidly expands its network of hanging roots, so that it starts absorbing nutrients before other competitors arrive.
07:56Water hyacinth appears.
08:07Water hyacinth appears.
08:10Water hyacinth is incredible in the other focus, the
08:16The race for space intensifies.
08:20A new competitor arrives.
08:23Ludwigia.
08:24It spreads by developing a chain of tiny rafts.
08:30And jostles to space with the densely packed leaves of mosaic plants.
08:42...or are racing to claim as much sunlight as possible.
08:57They flower quickly before the floodwaters recede.
09:12And these surface dwellers also have competitors, including one that has been waiting in the depths and is now stirring.
09:34It's a monster.
10:04It's well armed.
10:06It's well armed.
10:21It clears space for itself...
10:26...by wielding one of its buds...
10:29...like a club.
10:36And now...
10:39...it dominates the surface.
11:00This is a leaf of the giant water lily.
11:24It expands by over 20 centimeters a day...
11:29...and eventually measures more than two meters across.
11:37Its immense leaves are supported by a network of air-filled struts...
11:42...and protected by spines two centimeters long.
11:51The leaves float high in the water...
11:53...and their surfaces are dotted with tiny holes...
11:57...drains...
11:58...that help them ensure that rainwater doesn't accumulate and sink them.
12:17Nutrients from the fertile mud below...
12:19...are carried up by tubes in its stem...
12:22...to fuel the leaf's expansion.
12:33Over the next few months...
12:35...the lily will produce some 40 or so of these gigantic leaves.
12:49And as each one reaches the surface and expands...
12:53...more and more light is taken from those plants...
12:56...that are trying to grow beneath.
13:11Competitors are pushed aside.
13:37Some are crushed...
13:40...or secured.
13:58Some were типа-
14:20Eventually, its immense leaves pressed their margins against one another...
14:25Totally cutting off the light from the plants beneath them.
14:32The battle is over.
14:36And victory is total.
14:57The frozen water world of Lake Akan in northern Japan.
15:06Home to one of the strangest and most primitive of plants.
15:13It's an alga, like those that appear so mysteriously in our ponds.
15:22But this one is truly extraordinary.
15:32Each spring, the melting ice releases soft,
15:36velvety balls of interwoven threads called marimos.
15:45This one is small, no bigger than a walnut.
15:51But there are lots of them here.
15:59They attract the attention of visiting hooper swans.
16:32But there is one way for the marimo to escape from the danger.
16:37And it depends on a change in the weather.
16:40But there is one way for the marimo to escape from the danger.
16:44Fortunately, in the spring, winds sweep across the lake.
16:51Creating currents that carry some of the marimos
16:55beyond the reach of hungry swans.
17:01It's the start of a remarkable journey.
17:22They are gently carried back and forth by the currents
17:25so that the marimos become more and more spherical.
17:36And slowly, they travel into deeper water.
17:53Here, there are great numbers of them.
17:56Certainly, many millions.
17:59Some are the size of basketballs.
18:08They are safe from swans,
18:11and the water is still shallow enough
18:13for some sunlight to reach them.
18:16It seems a perfect home.
18:19And so it is.
18:22Almost.
18:25The snag is that these waters also carry a fine sediment
18:30that can clog the marimo's surface,
18:33cutting off the all-important light.
18:39But the marimos are not entirely immobile.
18:51They dance.
19:02The winds blowing over the lake's surface create currents beneath
19:07teeth that are sufficiently strong to move the marimos.
19:18They rub against each other,
19:21and in just a couple of hours of gentle movement,
19:24they're all clean once more.
19:33As they spin, every part of their surface gets enough time in the sunlight to keep growing.
19:39the wind blowing.
19:58This is the heart of the Amazon.
20:18There are water worlds here that are so remote that even today few people have ever seen them.
20:27This barely explored tributary is the Rio Claro.
20:33And here, when conditions are just right,
20:37it's possible to witness a rare and remarkable spectacle.
20:51The river is so crystal clear that its bed is bathed in sunlight.
21:03The magical landscape of miniature mountains and valleys.
21:22It's carpeted by pipewort, fanwort, and star grasses.
21:39As the sun climbs in the sky,
21:45bubbles of gas appear.
21:49Evidence of photosynthesis.
22:03Deep inside the plant cells, tiny structures called chloroplasts move towards the light.
22:14They absorb carbon dioxide,
22:16and use the sun's power to synthesize the sugars that the plant needs to grow.
22:26And, as a by-product, they release oxygen.
22:33The gas that we, and all other animals, must have in order to breathe.
23:01Now, in late afternoon, bubbles of oxygen make the river water fizz, like champagne.
23:12Wood��는 teasers, �ordbold's air nourished by the sea of delight
23:13even with the resc gicios that we waste each day.
23:13By Helloestому, this is wam- CHEAP,
23:14From a-c Policy switch to paint,
23:35Now today is the gem-Chap of the stars.
23:37I was hoping to their last name's experience for healing.
23:56The plants can become so buoyant with gas that they rise to the surface, even carrying
24:05the bedrock with them.
24:17Only in this remote water world can this spectacular natural wonder be seen.
24:32EASTERN VENEZUELA Here, rectangular table mountains known as Te Puy stand above the tropical forest.
24:49There are more than 50 such isolated mountain plateaus here, each home to a unique community
24:56of plants.
25:01Downpours are so torrential that no soil can accumulate on their broad rocky summits, and
25:08some plants living up here have to find their nutrients from another source.
25:21These are bromeliads.
25:28Their leaves are shaped like a funnel and collect grain water which accumulates in the center.
25:40This small pond is colonized by all kinds of tiny animals.
25:54And it is their bodies when they die that provide some of the nutrients the bromeliads need.
26:02This makes a good partnership in which both parties can thrive.
26:08But it can be exploited by a plant predator.
26:17Oh, and that's what we have.
26:18I have to hold for the kingdom to the San Francisco.
26:18And that's basically the land of the San Francisco.
26:25So our friends will not be pots and Voratina.
26:26And we're going to get the best possible prey to the benefits of the sea.
26:27Bye.
26:27Bye.
26:30Bye.
26:31Bye.
26:33Bye, bye.
26:37Bye, bye.
26:42Bye, bye, bye.
26:44This probing stem belongs to a plant called a bladderwort.
26:51It, too, is in need of nutrients.
27:02And a well-stocked Promeliad pool is just the place to find them.
27:10This one is full of aquatic animals.
27:41The bladderwork begins to change into a hunter.
27:50It develops bladders and removes sufficient of the water within them to create a partial vacuum.
28:04Each bladder has a trapdoor beside it with trigger hairs.
28:12Now, all the bladderwort has to do...
28:18...is to bite its time.
28:38It only takes one touch...
28:41...for the trapdoor to snap open...
28:47...and suck in its prey.
28:55It's all over...
28:57...in a millisecond.
29:09And after it is fed...
29:11...a bladderwort has enough energy to produce another tendril...
29:16...to search for another Promeliad pool.
29:35Swamps and bogs are also poor in nutrients.
29:41So several plants that live in such places catch insects, too, if they can.
29:59The leaves of sundews are covered with long red hairs, each tipped with a droplet.
30:27These glistening globules are, in fact, glue.
30:48Once the sundews detect the taste of their victim's body...
30:53...they flood it with digestive enzymes.
31:07The little body disintegrates.
31:14And the sundew gets the nutrients it needs.
31:24Another plant has an even more elaborate way of catching a meal.
31:35The Venus flytrap has leaves that are lined with interlocking teeth.
31:47It attracts insects by producing a sweet perfume...
31:50...just as a flower does.
31:54It, too, has a hair-trigger.
31:58It, too, has a hair-trigger.
32:09And another insect is caught.
32:25But the technique is more complex than it might seem.
32:33The Venus flytrap has a problem.
32:36It needs to avoid false alarms.
32:40Snapping shut on something inedible.
32:43Like a raindrop or a little bit of twig.
32:47That would be a waste of both time and energy.
32:51So how does it avoid that?
32:54Well, it does it by counting.
32:57If I touch this one, sensitive hair just there...
33:05...no reaction.
33:06That could be a false alarm.
33:09But the plant remembers that for 20 seconds.
33:12And if I touch it a second time within that time...
33:17...then that's much more likely to be worth eating.
33:20And so...
33:24It closes.
33:28So far, so good.
33:31But now it needs to be absolutely certain...
33:34...that it's got something worth eating.
33:36So it continues counting.
33:39Only after it has totted up five separate touches to those hairs...
33:44...will it give the final squeeze.
33:48And then begin to produce the liquid from the surface of the leaf.
33:51...which will dissolve the body of its unfortunate victim.
33:58The flytrap now has enough energy to produce flowers...
34:03...and attract pollinating insects.
34:16Wind and insects between them pollinate virtually all land plants.
34:22But neither method can be used by plants that live entirely underwater.
34:28So some lead double lives.
34:34A chalk stream in southern England...
34:37...and swaying in the current is a plant for which these rivers are famous.
34:43This is water crowfoot.
34:46A kind of aquatic buttercup.
34:48For most of the year, it is underwater.
34:52And if I take this underwater camera...
34:58...you can see its floppy stems grow horizontally.
35:03That reduces the risk of being swept away by the current.
35:09But each spring, when it's time to flower, it produces something crucially different.
35:17A stem that is stiff enough to resist the current...
35:22...and lift its flowers into the air above.
35:46And now, of course, they can get help from insects.
36:06So, every year, in part at least, water crowfoot becomes a land plant.
36:15And provides us with one of the loveliest natural spectacles of the early English summer.
36:31Water crowfoot is not the only water plant to lift its flowers above the surface.
36:42Plants do so all around the world.
36:50From the swamps of the Pantanal...
36:58...to the lakes of Thailand...
37:01...they all burst into spectacular bloom.
37:15Once they've been pollinated, they produce seeds.
37:31And now their flowers have done their job.
37:34Some return to a life...
37:38...underwater.
37:44Now they must ensure...
37:47...that some of their seeds will find suitable places in which to germinate.
38:06Bulrushes, every year, produce these long, brown, velvety objects.
38:14Look what happens when I break one open.
38:20It contains almost a quarter of a million seeds.
38:32Each seed is attached to a delicate parachute.
38:42Even the slightest breeze will lift it, and may carry it for very long distances indeed.
38:51So, even though suitable stretches of fresh water are few and far between, there's a good chance that at least
38:59one will end up in a place where it can grow.
39:11Much bigger seeds, of course, can't travel by air.
39:22A river can provide transport, but it's a one-way journey, downstream, that often ends up in the sea.
39:35And that's not ideal.
39:39So how can any riverside plant avoid this and travel upstream?
39:48Here, along the Bonito River in Brazil, a variety of trees manage to do exactly that.
40:02They embed their seeds in the middle of soft, sweet fruit.
40:24Monkeys, such as these capuchins, make a meal of them just as soon as they're ripe.
40:36But monkeys are very wasteful feeders, and what's not eaten ends up in the river and is washed away.
41:01But not all.
41:21In the fruiting season, hundreds of Pirraputanga fish gather beneath these trees.
41:37But the Pirraputanga want more than the monkeys' leftovers.
41:44The brightly colored fruits are clearly visible even to the fish in the water below.
42:00And some manage to claim them even before a monkey does.
42:18This isn't a skill mastered by just one particularly successful acrobatic fish.
42:24Many of the Pirraputanga can do this.
42:33Nor is this a disaster for the tree.
42:42Far from it.
42:49These Pirraputanga are migratory, heading many miles up-river to spawn.
43:04The trees by enticing the fish to eat their fruits have a perfect means of
43:09transport for their seeds. With luck the seeds will be deposited many miles upstream.
43:36The ability to colonize new habitats has allowed one group of flowering plants to venture out
43:43of freshwater and into a world that may look the same to us, but for a plant is crucially
43:51different. The much greater, saltier world, the sea. This is a fruit from one of the most
44:07important plants on the earth today, the seagrass.
44:20This particular one is floating off the coast of Formentera in the Mediterranean.
44:37A hundred thousand years ago, a seagrass seed like this sank to the sea floor just here.
45:00And eventually it produced a great meadow. A meadow that is still flourishing today.
45:17It did so by cloning itself. Now, over ten miles across, it's not only one of the largest
45:28living organisms on earth, it's also one of the oldest.
45:41And it supports a rich community of many kinds of animals.
45:51It's become a kind of marine savanna.
45:59Over a thousand species now live here. Some, like these elegantly camouflaged pipefish,
46:07live nowhere else but amongst the seagrass.
46:20Seagrass fringes many of the world's coasts.
46:31Turtles depend upon it too.
46:37And so do dugong, animals that are sometimes called, very appropriately, sea cows.
46:53Today, seagrass plays a critical role in maintaining the health of our planet.
47:01It creates stores of carbon around its roots at an enormous rate.
47:0635 times faster, in fact, than plants that live on the floor of a tropical rainforest.
47:16Here, off Formentera, it's possible to see beneath the living seagrass,
47:21layer upon layer of trapped carbon that the plants have accumulated over the past 2,000 years.
47:36Seagrass, however, is easily destroyed by human disturbance.
47:40A third of the world's underwater meadows have already been lost,
47:44and many more are in decline.
47:55Biologists are now striving to not only protect the remaining meadows, but to restore them.
48:04One plant at a time.
48:07One plant at a time.
48:14Seagrass could be a valuable ally in our fight against climate change.
48:23Today, water worlds everywhere are under threat.
48:33Many of their inhabitants are disappearing without us even being aware of their existence.
48:48The plants that grow in water are probably the least noticeable.
48:52They're certainly the least studied.
48:55But the more you know about the problems of living in that way,
48:59the greater the wonder of their success.
49:03Surely, they deserve more of our attention and, most importantly, our care.
49:26This vast wetland is the Pantanal.
49:30The water worlds team are heading to a plant battlefield.
49:36The home of Brazil's giant water lily.
49:42This is like seeing the end of a war.
49:45There are leaves growing on top of each other, flowers going through leaves.
49:48It's unbelievable.
49:52To capture this story in all its detail would take over a year,
49:57and require a unique green planet approach, both filming here and in a parallel mini Pantanal,
50:05in deepest darkest Devon.
50:12This is the unique world of specialist time-lapse cameraman, Tim Shepard.
50:20Tim has the reputation of being able to think like a plant.
50:26It's absolutely crucial that you get the plant really happy.
50:30And to make the giant lily feel totally at home,
50:33Tim must build a little piece of Brazilian wetland.
50:39First, a 10,000-litre tank.
50:45Hundreds of bricks, almost a thousand kilos of soil, and countless cups of tea later,
50:52the foundations are complete.
50:55So far, so good.
50:58Now, time to prepare for the new green planet camera system.
51:03We're trying to assemble the main gantry framework,
51:07so that we can mount the moving rig on top of it.
51:10So it's a bit of a fiddle to get all the screws in all the right place, basically.
51:16After a few weeks, the building works are complete.
51:21The flood can now begin.
51:30Tim needs to be sure everything in the room is heated to tropical temperatures.
51:40Before the star of the scene can move in.
51:46Carefully grown at the Royal Botanic Gardens at Kew,
51:50especially for us.
51:56Everything depends on this one plant.
51:59There will be no time for a second attempt.
52:04And even more important for Tim,
52:06to keep his guests happy and healthy.
52:10This big monster needs a lot of feeding.
52:13We found we need about high sandbags full of compost
52:17every two or three weeks.
52:19So we just sort of lower them in,
52:21and stick them down by the roots.
52:23There we go.
52:24Once the Devon giant settles in,
52:28the Pantanal crew are continuing to get their shots.
52:33Time to see some giant water lilies underwater.
52:37And I hope there's no anaconda.
52:51The pressure is now on Tim.
52:57After months of pampering, the giant lily is ready for action.
53:04First thing to film is a leaf spike rising up from the depths.
53:11Luckily, there are no anacondas here.
53:16The special camera weighs over 40 kilos.
53:23The new rig means Tim will be able to follow the emerging plant in any direction.
53:34Oh, fancy!
53:37The technology is working well, but nature is starting to derail Tim's plans.
53:44We've got really tangled up with all these weeds.
53:48What happens is we've got a bit of an ecosystem developing here.
53:53Before you know it, you get masses and masses of algae growing in amongst it all.
54:02We've got to release some anaerobic gases there.
54:05No, not me, the algae.
54:10State-of-the-art tools help keep the algae at bay.
54:16Good kitty!
54:25Just in time for Tim to film Levi's.
54:28Liftoff.
54:40that's quite nice coming out of water look at that
54:43jim stokers can now shift to the battle that's starting to take place on the surface
54:52i'm trying to film this new bud coming out on this lily leaf it'll take about three days to
54:57grow from where it is now somewhere in this zone between these two other leaves i want that to last
55:03about 10 seconds 10 seconds is about 250 frames that works out about one frame maybe 20 minutes
55:12the plants don't read scripts it's nature it doesn't always do what you think it's gonna do
55:26we've had a few full starts where the leaf has swung out of shot and gone somewhere else
55:36or it just grows a lot quicker than you thought
55:43it's a challenge to get things right but with the combination of tim's expertise and the new
55:48camera system results are starting to look good i think the difference now with this series is we
55:55can bring the plants much more to life as characters and tell their story in a much more dynamic way
56:04it's great to be able to follow them around much more in the way you'd film an animal behaving
56:19these rigs have given us a whole new realm of possibilities
56:24after over a year of filming and recording a hundred thousand separate images
56:29the secret life of the giant water lily and the battle of the pantanal has been revealed
56:42next time on the green planet the ever-changing seasonal world full of hunters tricksters
56:51and unlikely alliances
56:57plants here are in a race against the clock timing is everything
57:07the open university has produced a poster that explores the vital role that plants have for our planet
57:15to order your free copy call 0300 303 4200 or go to bbc.co.uk forward slash green planet and
57:27follow the links to the open university
57:32you can hear david's guide to the green planet with music from the series a mindful mix
57:38on the bbc sounds app now and including one of the finest classical actors anthony
57:43share who died last month henry the fourth over on bbc four now next here a homeless man in desperate
57:50need
57:50need of help on call the midwife
57:53you
57:53you
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