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AnimalsTranscript
00:00Thank you for listening.
00:36The relationship between plants and humans is extraordinary.
00:44We've been adapting to each other for as long as we've been on the planet.
00:52We rely upon plants for almost everything.
00:56The air we breathe, the water we drink, the food we eat, much of the clothes we wear,
01:04and some parts of the world, the very buildings in which we live.
01:09But that relationship is now changing.
01:15How it changes next will shape the future of our green planet.
01:35Some plants have the ability to live alongside us.
01:42Even when we make it extremely difficult for them to do so.
01:49This is Piccadilly Circus in the heart of London.
01:55It will be difficult to imagine a more hostile place for a plant.
02:02And yet, even here, plants will find a way.
02:18Plants like this may seem to follow us wherever we go.
02:27We call them, perhaps a little unkindly, weeds.
02:35In fact, these plants are pioneers.
02:39The ones that are most able to take advantage of new habitats,
02:44even very harsh ones.
02:51This wall is at least a hundred years old.
02:55It's like a sheer cliff face with no sign of soil.
03:00And yet, this ivy-leaved toad flax thrives here.
03:06How?
03:08The plant grows towards the light,
03:11with its flowers facing outwards to attract pollinators.
03:16But once they've succeeded in doing that,
03:19and the seed pods start to develop,
03:21its behavior changes.
03:25And now, the pods turn and grow away from the light,
03:30seeking the darkest place they can find.
03:34A crevice, perhaps.
03:35Like this one.
03:42It's all the toad flax needs.
03:45It can now germinate and start to produce a new plant.
04:07Other pioneers have a different strategy.
04:10They, instead, distribute their seeds far and wide in great numbers.
04:17Sow thistles are masters of this trick.
04:22Each of its seeds is equipped with a tiny, downy parachute,
04:26which will catch the slightest breeze.
04:31And they can travel extraordinary distances.
04:36They can rise a mile high in the sky
04:38and reach places hundreds of miles away from the parent plant.
04:47The seeds only need to find the tiniest chink,
04:51and they can take hold.
04:57We barely notice many of these plant invaders.
05:03But here, in the heart of Hong Kong,
05:06strangler fig seeds that landed on a stone wall generations ago
05:11have spread their flexible branching roots far and wide.
05:21They can be anchored so firmly that they become a part of the city's architecture.
05:30This is, perhaps, the ultimate weed.
05:37But there are places where the extraordinary abilities of fig trees
05:42have created a very different relationship with human beings.
06:01Megalea, in northeast India.
06:05A high-altitude plateau riven by dizzyingly steep fathers.
06:14It's home to the Kasi people,
06:20who've learned how to use the remarkable properties of fig trees
06:24to help them live in such difficult country.
06:31As in Hong Kong, the tree's numerous roots anchor it firmly,
06:37here, to steep mountain sides.
06:43These roots can grow up to two and a half centimeters a day.
06:47They are unusually strong, flexible,
06:51and can develop into a multitude of shapes.
06:57The Kasi persuade them to provide them with stairs.
07:07The monsoon season brings a seemingly insurmountable challenge
07:11for Kasi communities.
07:17This is the wettest place in the world.
07:22Nearly 30 centimeters of rain can fall in a day.
07:37Rivers become lethal torrents, dividing communities from each other.
07:43This is when the relationship between fig trees and the Kasi becomes most important.
07:52They deliberately plant fig trees near the rivers.
07:56When they're mature enough to have developed many hanging roots,
08:00shining star Kongthor begins working with them.
08:08The young roots are the best one for starting their project.
08:17These roots grow plenty in number.
08:20They are more flexible.
08:24He guides the roots through bamboo tubes
08:27that are pointed towards the opposite river bank.
08:49These strands will combine as they grow,
08:52sharing nutrients and resources
08:54and becoming stronger than a lone strand could ever be.
09:02The roots that are tying together
09:05are like the connection
09:08between the Kasi people.
09:13So the roots
09:14that are connecting
09:16is like a person
09:18who helps each other.
09:26As the years pass,
09:29the growing roots become
09:31a living bridge.
09:51As they grow,
09:52they become ever stronger
09:54and more stable.
10:02living bridges
10:04are the lifeline
10:05for the Kasi people
10:06as a whole.
10:19This unusual relationship
10:22has allowed the people here
10:24to thrive
10:24in an otherwise challenging landscape.
10:43But there are plants
10:45that have found a deeper partnership with us
10:48and in doing so
10:49have changed landscapes
10:51across the globe.
10:55It began over 10,000 years ago
10:58with plants
10:59that we found
11:00especially good to eat.
11:04At first,
11:05this relationship
11:06created challenges of its own.
11:10Many of the ancestral grasses,
11:13like these wild oats,
11:15Misrael,
11:15have a trick
11:16to ensure
11:17that their seeds
11:18are planted
11:19in the perfect place.
11:21Each seed head
11:23at the top
11:24carries two long bristles
11:26called awns.
11:28And when a seed
11:30drops the ground,
11:31these awns
11:33do something
11:33truly extraordinary.
12:13They walk.
12:21The awns twist
12:23as they dry out
12:24during the day
12:24and then
12:26when they get wet,
12:30they untwist.
12:35Tiny hairs
12:36grip onto the ground
12:37keeping the individual
12:39moving forward.
12:46In this way,
12:47the seeds
12:48work their way
12:49along the ground
12:50until eventually
12:51they find a rock
12:52to hide under
12:53or a crack
12:55to drill into.
13:02This adaptation
13:03is useful for the plant
13:05but not for us.
13:08It's hard
13:09to collect seeds
13:10when they drop off
13:11and walk away.
13:13So our ancestors
13:15selected plants
13:16whose seeds
13:17don't drop off,
13:19don't have legs
13:20and don't bury themselves
13:22out of reach.
13:26They also selected
13:28those individuals
13:29which put their energy
13:30into developing
13:31much larger seeds.
13:35Close relationships
13:37like this
13:37have developed
13:38all over the world
13:41producing the plants
13:42that are now
13:44our crops.
13:50this may seem
13:51a poor deal
13:51from the point
13:52of view of plants
13:53but not so.
13:55We eat their seeds
13:57but in return
13:58we cherish
13:59and cultivate them
14:02and now
14:03they are widespread
14:04and far more abundant
14:06than their wild ancestors.
14:13You might call this
14:15a bargain
14:16between ourselves
14:18and plants
14:19and over the years
14:21it's proved
14:21extraordinarily powerful.
14:33In the beginning
14:35the bargain
14:36operated
14:37on a small scale.
14:47plant,
14:49tend
14:49and harvest
14:51by hand
14:51in small patches.
14:58Over time
14:59these plants
15:00produced more food
15:02increasingly efficiently.
15:09And the partnerships
15:10became more exclusive.
15:16we started doing
15:18more and more
15:19for a small number
15:20of chosen species.
15:30These few
15:31persuaded us
15:32to eliminate
15:33their competitors
15:35cure their diseases
15:38poison their enemies
15:42and keep them
15:44well watered
15:45even when other species
15:47face drought.
15:50Fewer and fewer
15:51plant species
15:52like soy,
15:54wheat and rice
15:55now occupy
15:56more and more land.
15:59So now whole
16:01landscapes
16:02are dominated
16:02by a single
16:04species of plant.
16:08A monoculture.
16:16this is the
16:17central valley
16:18of California.
16:21The biggest
16:22orchard
16:22in the world.
16:25A million acres
16:26of just one
16:27type of tree.
16:30Almonds.
16:40Each flower
16:41if it's fertilized
16:42by pollen
16:43from a different
16:43almond tree
16:45will produce
16:47an almond nut.
17:00The flowers
17:01patterns
17:01and scent
17:02have evolved
17:03to attract insects
17:04and bribe them
17:05to do that job
17:06for them.
17:08The pollen
17:09doesn't have to move
17:10far
17:11it just needs
17:12to reach
17:12a neighboring tree.
17:17There are about
17:1920,000 flowers
17:21on each tree.
17:26And 140 million trees.
17:32That is billions
17:34of flowers
17:35all calling out
17:37at once.
17:41But here
17:42the beauty
17:43of the blossom
17:44is wasted.
17:45To make way
17:46for these almond trees
17:47the land was
17:49in effect
17:49wiped clean.
17:54Countless wild
17:55species
17:56of plants
17:56and animals
17:57were removed
17:58including
17:59critically
18:01pollinators.
18:04So now
18:04the flowers
18:05need help
18:06and lots
18:07of it.
18:18of the
18:21of the
18:22of the
18:4240 billion honeybees
18:46tromped in from all over the United States.
18:58The orchard is only in bloom for a few weeks, so the almonds need the bees to get to work
19:04immediately.
19:21Each bee can visit thousands of blossoms a day.
19:28And while they take most of the pollen they collect back to the hive, they also drop some
19:34pollen at each stop.
19:36And so, with luck, the flowers are all eventually fertilized.
19:44Day after day, the process is repeated.
20:01Flower after flower, tree after tree.
20:30By the time the petals fall, two and a half trillion flowers have been successfully pollinated,
20:37and will now grow into two and a half trillion almonds.
20:44This type of intensive, streamlined agriculture produces amazingly high yields.
20:56But monocultures are fragile.
21:00While they can function effectively when conditions remain stable, it only takes a small change
21:06to create catastrophe.
21:22Lodgepole pine, a very valuable timber tree grown extensively in Western Canada.
21:34Millions of acres of the same species, all the same age and the same size.
21:43For centuries, lodgepole forests have lived in a natural balance with their enemies, including
21:50this one.
21:53The mountain pine beetle.
21:59In summer, female beetles start hunting for a suitable nursery in which to lay their eggs.
22:13The ideal site is a mature lodgepole pine with bark thick enough to feed a female's brood,
22:21and, critically, to protect them from the bitter cold of the coming winter.
22:31Once under the bark, she tunnels upwards,
22:39laying her eggs as she goes.
22:46A single female beetle can lay a hundred eggs in a season.
23:06When the larvae hatch, they grow by feeding on the inside of the bark.
23:13As they do, they damage the channels that transport water and nutrients between the roots and needles.
23:34For centuries, the freezing northern winters killed the majority of larvae, so tree and beetle remained
23:41in balance.
23:43But now, with the climate changing, the winters aren't cold enough to control the beetle numbers.
23:53Needles turning red are a sure sign that the trees are dying.
24:06The beetle plague spreads like wildfire across a landscape covered by a monoculture of similarly vulnerable trees.
24:18Since the first mass outbreak 40 years ago, trillions of trees in North America have been killed by the mountain
24:25pine beetle.
24:33Loss of plant diversity makes any habitat more vulnerable to changing conditions.
24:41Now, with climate changing so fast, we're losing plant diversity just when we need it the most.
24:50Two out of five plants are now facing extinction.
24:57Of course, the loss of any one species is in itself a tragedy.
25:03But such a loss erodes the stability of a whole ecosystem.
25:09And that should be of great concern for all of us.
25:16We need an insurance policy.
25:20A hedge against extinction.
25:26This is Q's millennium seed bank.
25:33Packets of seeds arrive here from all over the world.
25:38These are from a relative of the yucca plant, which grows in central Mexico on the slopes of volcanoes and
25:47nowhere else.
25:52Most of the seeds are from plants that are threatened.
25:57Some, indeed, have gone extinct since their seeds arrived here.
26:02But here, at least, those seeds are safe.
26:08When they arrive, they're processed and sealed into airtight jars.
26:17Seeds are then brought underground to be stored in a vault, like this one, at minus 20 degrees centigrade.
26:32Since the bank was founded, two billion seeds from 40,000 different species have been brought and stored here.
26:51Because the seed contains everything it needs to start a new plant, each and every one of them represents a
26:58little grain of hope.
27:15Hope that one day we will make it possible for the seeds of these rarities to grow in the wild
27:22once again.
27:28The seed bank certainly gives us options when a species becomes rare or even extinct.
27:41But around the world, people are trying ways to keep natural plant populations healthy where they should be.
27:48In the wild.
27:59Hawaii.
28:0490% of the plant species here are found nowhere else in the world.
28:15Many are threatened by a plant invader called Myconia.
28:24It was brought to the island of Maui in the 70s as an ornamental plant.
28:30In its native Mexico, it grows in balance with a rich variety of predators, competitors and diseases.
28:44It grows taller than most native Hawaiian vegetation and little can grow beneath it.
29:00On the island of Maui, with nothing to keep it in check, it creates a stifling monoculture.
29:10Myconia, it would appear, is doing very well for itself.
29:14Myconia, it would appear, is doing very well for itself.
29:19But today, it's under attack.
29:27On level ground, a single dedicated team can keep Myconia in check.
29:41But unfortunately, this plant can spread to places impossible for people to reach on foot.
29:54Just one plant can produce around 10 million seeds a year, enough to cover this entire landscape.
30:04With so much at stake, the team have come up with an extraordinary plan.
30:14We'll see you in the next one.
30:28We can see you in the next 500 in the past.
30:54It's too dangerous to land here.
31:00But they don't need to.
31:08A marksman with great skill can shoot at the Myconia with paintballs full of herbicide.
31:21The perfect shot is one that hits the stem, so ensuring that the herbicide spreads throughout the plant.
31:42The method is so precise that with careful flying and accurate aim, they can kill the intruders without damaging any
31:51wild plants.
32:01They can kill the intruders with the plants.
32:04The
32:04The
32:04The
32:04The
32:25Destroying alien invaders is not the only way to help the native plants here.
32:38This is Waikamoi Preserve, the last surviving fragment of a high-altitude Hawaiian rainforest,
32:47and home to one of the world's rarest plants, Holokea.
32:57There are only 57 fully grown individuals left in the wild.
33:07Their peculiar flowers evolved to suit the beak of a bird found only in Hawaii, the i'ivi.
33:16The bird is now so rare itself that today these partners seldom, if ever, meet.
33:26So the chances of Holokea getting pollinated are very slim.
33:32But a strange new partnership might just save it.
33:38I look at losing a plant as flying in a plane and taking a screw out, and yeah, the plane
33:47will fly and you might be able to take a couple of screws out and keep flying, but eventually
33:54you're going to crash.
34:06Hank knows where to find every one of the last 57 plants.
34:12And he returns every year to act as their pollinator.
34:17We have to step in and play that role as pollinator, batch maker.
34:33Hank collects the pollen from the male flower and dusts it onto a female flower of a different
34:40plant.
34:43He's currently their life support, but his goal is for Holokea to thrive without him.
34:51So before he leaves, he plays the call of the i'ivi bird.
35:10Hank hopes the sound will attract the living birds, and if they come, that they will reconnect
35:16with the last Holokea and rekindle their vital relationship.
35:33I believe all species are important, and I believe we have a duty to act.
35:49We need to act not only in the wild places, but even in those where we live and where
35:57we farm.
36:04Like much of the world, Kenya is losing thousands of native trees annually, ones that local people
36:11rely on for so much, especially fuel.
36:18But here, people have come up with an ingenious way to reverse some of that loss around them.
36:32At a factory in the outskirts of Nairobi, workers collect and sort waste charcoal dust.
36:45The seeds of carefully selected native trees are mixed with the dust.
36:54This carbon coat will protect the seeds from hungry animals until the rains arrive.
37:09These are seed balls.
37:27In the village of Tebuesi, acacia trees are becoming scarce, cut down by previous generations
37:35to make charcoal.
37:57But the students at this school make forest restoration child's play.
38:22The nutrients in the dissolving charred dust will give each little seed a good start.
38:34If only a handful of these seeds grow into a tree, the effort has been well worth it.
38:41Every mature acacia tree can itself produce thousands of seeds a year.
38:5213 million seed balls have been distributed in Kenya alone.
39:01And the methods by which they are dispersed are ever more inventive, to say the least.
39:24This technique is being repeated around the globe.
39:28Seed ball making workshop.
39:32People are choosing seeds of local native plants, giving them a little initial help, and bringing some wild plants back
39:41into the world around them.
39:48But is it possible, even in our most extreme monocultures, to invite a bit of wildness in?
39:58And with it, a bit of resilience.
40:04I have two different kinds of forage growing in my orchard.
40:08The yellow that you see behind me is a variety of different mustards.
40:15And then after the bloom, we're going to see some clover blossom.
40:21This mix of plants means the bees can feed before and after the brief almond bloom.
40:29And they also get a more balanced, healthier diet.
40:34In the meantime, it's going to provide habitat for all sorts of insects and the bees.
40:40Probably some rabbits.
40:43It's a step towards establishing a better, more stable system.
40:49It's about finding balance.
40:51That's what we're trying to do here.
40:53Find a balance.
40:58Can humanity, globally, find a new balance between wild plants and those we have domesticated?
41:10Around half the usable land on Earth is taken up by agriculture.
41:15Do we really need that much?
41:19Maybe not.
41:22It's a remarkable fact, but around 80% of all cultivated land is used for raising livestock for us to
41:34eat.
41:36Raising animals can be a sustainable way to create food.
41:40But in many places, plants can produce the same amount of protein on a fraction of the land that animals
41:48need.
41:51What could it mean for wild plants if the global balance between plant eating and meat eating shifted?
42:01It may sound odd, but the more plants we eat, the more space there will be for wild plants.
42:13Remarkably, it's possible to restock even highly degraded land with wild plants.
42:26In Brazil, the needs of cattle ranching drive most deforestation.
42:38Thirty years ago, the owners of one former cattle ranch wanted to restore their land to the Atlantic rainforest that
42:47once covered it.
42:51They had no idea if it could be done.
42:55The land was so bare and eroded.
43:00But they were determined to try.
43:05First, they cleared the introduced African cattle grasses, invasive plants that outcompete most of the native plants.
43:20The grasses were replaced by seedlings grown from seeds gathered in nearby remnants of Atlantic rainforest.
43:37The Earth Institute, or Instituto Terra, as the ranch is known now, was encouraged by early success and expanded its
43:47scope and ambition.
44:06In five years, trees covered the land again.
44:11And within ten, it was clear something remarkable was happening.
44:36When rain falls, it now no longer simply runs off the land, leaving it parched.
44:47Instead, it clings to the plants, to every root, stem and leaf, and then slowly filters to the forest floor.
45:01And so, previously dry streams burst into life for the first time in decades.
45:13The Institute never introduced animals or plants other than the trees.
45:24The animals came back on their own.
45:29Small ones came first.
45:32Small ones came first.
45:48Small ones came first.
45:49And then, very recently, camera traps left in the forest captured images beyond the hopes of everyone involved.
46:02a maned wolf.
46:04A maned wolf.
46:05An animal that is being driven from its native habitat by deforestation, drawn to its favorite plant, the wolf fruit
46:15tree.
46:18Not only that.
46:25A puma.
46:30With cubs.
46:41The arrival of these precious top predators and their young shows what can happen when we make space for wild
46:50plants.
46:57We have, for centuries, robbed wild plants of the space and time they need to thrive.
47:06That has certainly not been to their benefit.
47:11Nor, ultimately, is it to ours.
47:20Our relationship with plants has changed throughout history and now it must change again.
47:27Whether it's what we eat and cultivate or whether it's what we like, we must now work with plants and
47:35make the world a little greener, a little wilder.
47:47If we do this, our future will be healthier and safer and in my experience at any rate, happier.
47:58Plants are, after all, our most ancient allies and together we can make this an even greener planet.
48:21Throughout the human episode, the green planet crew sought to capture the lives of plants confronted with the human world.
48:30But they also heard the stories of people deeply connected to the plants around them.
48:38Such as those at the front line of the battle to save Hawaii's native endangered plants from invasive species.
48:48If we don't get a handle on Myconia, we could lose everything that makes Hawaii special and unique.
48:57But before the green planet team could start work, they had to undertake some rigorous preparation.
49:04We're going into somewhere that has a very sensitive ecosystem, they're trying to protect it from invasives.
49:11Filming in a place so ravaged by invasive species meant they had to be 100% sure that they were
49:18not spreading any non-native stowaways themselves.
49:22They had to scrub and disinfect every item of equipment.
49:30With kit clean, the team first focus on filming the rare Holokea plant.
49:40Accessible only on foot.
49:49There are few pristine areas like this left in Hawaii.
49:54Only 40% of the land still has native vegetation.
50:00Most of it wiped out by invasive species like Myconia.
50:10Next on the list was to film the team waging war on Myconia, known locally as the Purple Plague.
50:20For crew member Asia, the work is not just a physical battle against this invasive species.
50:27It's deeply personal.
50:29I've been to the pristine areas so I know what it looks like and feels like, you know, to be
50:35in the presence of all that mana and spirituality.
50:43Those aren't just plants.
50:47Those are ancestors, spirits, you know.
50:51Controlling these invasive plants is a relentless job.
50:54And Asia is not just doing this for native Hawaiian ecosystems, but also to protect her ancestral relationship to this
51:02fragile landscape.
51:05So going through this, it feels good just to hack them and pull them out and be like, yeah, okay,
51:09take that, you know.
51:10We can sort of fight back.
51:13Asia's fierce passion to protect these native forests is evident.
51:19But the Purple Plague has spread to places Asia could never reach on foot.
51:26Taking to the sky is the only way to reach the front line of this battleground.
51:33With only enough fuel to stay airborne for two hours, the window for capturing this aerial battle is uncomfortably small.
51:43We have one day of doing the heli operations.
51:47The weather could completely mess us up if we get a system that comes in.
51:51Heli to heli is always dangerous and difficult.
51:56This flight is not just tense for Liz.
51:59For plant sniper Brook Manken, these short flights represent his only opportunity to hold back the invasion.
52:07Myconia left unchecked can be terribly damaging.
52:11The potential for one seeding plant, if it were to get far away from the population, reach maturity and put
52:18seeds out, then it's starting a whole new infestation.
52:22And once it occupies that entire area, then it's completely wiped it out.
52:31The helicopter is really important because you can fly in extreme terrain with these, like, thousand-foot cliffs and find
52:38Myconia that there would be no other way to get to these plants.
52:44The Myconia team are used to the aerial challenges of this battle, but for producer Liz, the pre-flight talk
52:52from the helicopter pilot brings home the lengths that this team go to in order to complete their work.
52:58So you're just going to be in the back here, and it's a hurricane in the backseat, literally a hurricane.
53:04So nothing loose. You don't want to put an arm, a head, a leg or a hand out.
53:08It's just going to blow behind you. And you don't want to stick your head out because if the headset
53:14comes off, then it's into the tail rotor and then it's bye-bye Maui.
53:18Pre-flight checks completed. The clock is now ticking to get into the air.
53:27This matters so much to everyone here. I definitely feel the pressure to get this right.
53:49To get within shooting distance of the plants, the helicopter pilot must carefully maneuver in to one of the area's
53:57deepest canyons.
54:07The target is in sight. Oh, yep, there he is. Okay, I'm, uh, I'm live and ready.
54:17With high winds gusting up from the waterfall, getting into position is tricky enough in one helicopter, let alone two.
54:26To give Brooke the best chance of hitting the Myconia, the pilot must get him within 20 meters of the
54:32plant and, ideally, at eye level.
54:34Any missed shot threatens to become friendly fire, harming the species he aims to protect.
54:41Ready? Yep. Here we go.
54:46Brooke must strike the stem of the plant to have the best chance of completely killing it.
55:08This has been a successful mission for both teams. The pilot's skills and Brooke's sharpshooting has saved another patch of
55:17forest, and Liz is relieved that she has the shot she needs.
55:21To do the story justice. It's over. It's over. It just looked amazing. Yeah, it looks good. It looks good.
55:32For Brooke and Asia, however, their work doesn't stop. Just holding back the tide of invasive species in Hawaii is
55:40more than a lifetime's work.
55:43But Asia believes that her fight is worthwhile.
55:46Everything we do is for the next generation, just like our ancestors and kupuna.
55:51It wasn't for them. It was for the next generation.
55:55And just to have my kids go into areas, like, where they can see they're still natives, where we don't
56:02have to go through all this invasive vegetation.
56:10You know, it's not just my responsibility. It's everyone's responsibility.
56:18You know, the Earth takes care of us, so we have to do the same. We can't just let it
56:23go by.
56:27We've got to take care, too.
56:37The Open University has produced a poster that explores the vital role that plants have for our planet.
56:45To order your free copy, call 0300 303 4200 or go to bbc.co.uk forward slash green planet and
56:58follow the links to The Open University.
57:06So I'm hearing Sister Monica is feeling a strong presence. Let's see what this is all about.
57:11In Call the Midwife, it's next on BBC One.
57:15.
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