- 18 minutes ago
Secrets of the Enchanted Forests | Extreme
2023 | Επ. 6/6 | HD
Διασχίζουμε τα πλουσιότερα και πιο ποικιλόμορφα δάση του πλανήτη, από την τροπική ζώνη μέχρι τους πόλους και παντού ενδιάμεσα. Γνωρίζουμε τους άγριους κατοίκους αυτών των μαγικών οικοσυστημάτων και μαθαίνουμε πώς τα δάση συνδέουν και θρέφουν τις ζωές αμέτρητων ειδών.
Μαθαίνουμε πώς τα φυτά και τα ζώα επιβιώνουν σε μερικά από τα πιο ξηρά εδάφη της Γης. Συναντάμε διψασμένα δέντρα που λειτουργούν ως οδοδείκτες για τους ελέφαντες, βλέπουμε έντομα να συνεργάζονται με φυτά για να καταφέρουν να επιβιώσουν και γινόμαστε μάρτυρες του χημικού πολέμου που λαμβάνει χώρα στη φύση.
2023 | Επ. 6/6 | HD
Διασχίζουμε τα πλουσιότερα και πιο ποικιλόμορφα δάση του πλανήτη, από την τροπική ζώνη μέχρι τους πόλους και παντού ενδιάμεσα. Γνωρίζουμε τους άγριους κατοίκους αυτών των μαγικών οικοσυστημάτων και μαθαίνουμε πώς τα δάση συνδέουν και θρέφουν τις ζωές αμέτρητων ειδών.
Μαθαίνουμε πώς τα φυτά και τα ζώα επιβιώνουν σε μερικά από τα πιο ξηρά εδάφη της Γης. Συναντάμε διψασμένα δέντρα που λειτουργούν ως οδοδείκτες για τους ελέφαντες, βλέπουμε έντομα να συνεργάζονται με φυτά για να καταφέρουν να επιβιώσουν και γινόμαστε μάρτυρες του χημικού πολέμου που λαμβάνει χώρα στη φύση.
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00:02Υπότιτλοι AUTHORWAVE
00:33Υπότιτλοι AUTHORWAVE
01:01Υπότιτλοι AUTHORWAVE
01:31Υπότιτλοι AUTHORWAVE
01:35Υπότιτλοι AUTHORWAVE
01:40Υπότιτλοι AUTHORWAVE
01:58The Namib
02:00is one of our planet's driest deserts.
02:08Dominated almost entirely by sand,
02:13sources of water are scarce here.
02:19Yet it is home to one of the world's thirstiest animals.
02:33The elephant.
02:36The elephant.
02:41This herd is led by its oldest female,
02:46the matriarch.
02:49The matriarch.
02:50She has one of the toughest jobs of any mother.
02:55She must find water for her family.
03:00in this parched wilderness.
03:08The herd are all counting on her and her knowledge of this extreme environment to lead the way.
03:23So she looks to the most reliable guide she knows.
03:29The desert's sparse and scattered forest.
03:36only specialist desert adapted tree species such as ana and mopane have any hope of surviving here.
03:48The ana tree's secret weapon is a long taproot that can seek out secret pockets of water buried 60 metres
03:59below ground.
04:02Keeping their thirst quenched and leaves green for most of the year.
04:10So they shine like a beacon against the dry sand.
04:18The elephants use these trees as signposts.
04:24This dispersed forest lines the root of a river hidden deep underground.
04:33And the healthier the tree, the closer it must be to water.
04:45To stave off dehydration, the elephants feed on moist leaves.
04:53But they eat sparingly.
04:58Every tree is precious.
05:01And they can't risk destroying future supplies.
05:13After days of walking.
05:17The heat and physical effort of this make or break journey.
05:23Brings the herd to its knees.
05:38The matriarch knows to trust the trees.
05:44They tell her she's getting closer.
05:48And soon, she spots the final sign.
05:55A forest of lush, new-growth mapani trees is a rare sight in this desert.
06:05These young trees have shallow roots.
06:10If water is within their reach, that means it's within the reach of elephants too.
06:31There's even enough water for a cooling bath.
06:41The Namib desert never stands still.
06:47The coastal winds shift the sand dunes daily.
06:51So the location of these sporadic sources of water are never guaranteed.
07:00The green markers in this desert forest may change their course over time.
07:07But they will always lead to water.
07:21From deserts to jungles, prairies to mountains, the crucible of extreme environments has created some real forest icons.
07:41Surviving volcanic eruptions, outliving the dinosaurs, and crushing rocks.
07:53The more inhospitable the location, the more remarkable the tree that grows there.
08:10The Chilean pine, also known as the monkey puzzle tree, is one of the longest surviving species of tree in
08:18the world.
08:22Endemic to the slopes of Patagonia's volcanoes, this danger-loving forest thrives in its perilous location.
08:32It actually requires a certain level of volcanic disturbance to prosper.
08:39Often referred to as living fossils, time appears meaningless for these trees.
08:46They have been growing here since the Jurassic period, when dinosaurs ruled.
08:54Its dagger-like leaves can remain on the tree for up to 30 years.
09:01And individual trees can live for thousands of years.
09:07Standing as silent witnesses to a changing world.
09:18An icon of Africa's dry forests is the impressively sturdy baobab.
09:28Often described as the tree of life, these extraordinary monoliths are the generous providers in these empty lands.
09:40With roots that stretch out over 50 metres, they draw up water and store it in their soft, hollow trunks.
09:51Keeping the soil humid so other plants can grow in its shadow.
09:59Their bark and branches create homes.
10:03Their fruit is a nutrient-packed superfood.
10:07They can even withstand the elephant's torture.
10:12Standing firm where few else can.
10:18But the elder statesman of the savannah is on a path to extinction.
10:26Although fully adapted to its extreme home, it is unable to cope with the rate of climate change.
10:35As they slowly disappear, so does the vital support they offer to hundreds of species and tribespeople in this area.
10:52But there are still many other unstoppable trees out there.
11:00The rock fig doesn't let anything get in its way.
11:06Not even a giant boulder.
11:10Its drive for water is so strong, it uses its roots to seek out every crack and crevice as it
11:18defiantly grips the edge of a rocky ridge.
11:26As the tree grows, it secretes special organic acids that weaken the rock.
11:37Then, as the roots expand like a living wedge, entire boulders are split in two.
11:54These are the extreme trees that forged an existence against all the odds.
12:15Even in the gentlest of climes, a forest must endure a daily onslaught from hungry beasts.
12:28In a dense, lush woodland with plenty to go around, trees can share the burden of having their leaves munched
12:35and branches stripped.
12:41But in extreme forests, trees are few and far apart.
12:49In a land with limited food and water, a lone tree can be a rare source of sustenance for wandering
12:57herbivores.
13:00And there is a real danger of it being completely devoured.
13:08So these trees need to fight back.
13:15One such tree is the camel-thorn acacia.
13:20This desert stalwart is locked in an escalating arms race with its greatest foe.
13:30The giraffe.
13:37A giraffe needs to eat more than 30 kilograms of vegetation per day.
13:45And very little is out of its reach.
13:49To counter these attacks, the tree has armed itself, covering its branches in six-centimeter-long punishing spikes.
14:03But the giraffe evolved dexterous lips and a half-a-meter-long prehensile tongue to deftly navigate around the spikes.
14:13And still pluck away at the leaves.
14:21So the acacia enlisted some backup.
14:28Its second line of defence comes from within the thorns themselves.
14:35Tiny bodyguards.
14:40Each tree in this woodland has several ant species living within it.
14:50Housed inside the hollow thorns, these ants will protect the tree in return for a regular supply of nectar.
15:05As the giraffe's lips move in, the ants swarm, delivering a barrage of painful stings.
15:20But this only works on young giraffes.
15:26Adults have toughened, leathery lips and appear undeterred by the pain.
15:33For these hard-mouthed adults, the tree has one final tactic.
15:40Chemical warfare.
15:45Once the tree senses it's under attack, it floods its leaves with a bitter-tasting toxin.
15:54In high doses, these chemicals could kill the giraffe.
15:59But they take a huge amount of energy for the tree to produce.
16:03So it releases just enough to render the leaves unpalatable.
16:13Finally, this works.
16:17But the giraffe simply goes in search of another acacia to eat.
16:23This may be a sparse forest, but the trees within it still look out for each other.
16:31So the beleaguered acacia sends out a warning.
16:36Through pores on its leaves, it releases a waft of ethylene gas into the air.
16:43The surrounding trees pick up this airborne message and follow suit, filling their leaves with toxins.
16:53Within 15 minutes, all the leaves in this woodland have turned distasteful.
17:01The herd is forced to move on, and the forest can stand down and reset.
17:10The tree's defences give the giraffe just enough time to eat, but never enough to destroy any one tree.
17:21Both sides have called a truce, for now at least.
17:34Even a tree so hell-bent on defence needs to soften up for the sake of its offspring.
17:45Once a year, the camel-thorn acacias need the help of a certain herbivore if their woodland is to survive.
17:58These are acacia seed pods.
18:01The tough outer casing is designed to protect the smaller, more delicate seeds inside.
18:09And the acid inside an animal's gut is the most effective way to soften them up and kickstart their germination.
18:23As the tree drops its ripened pods, the fate of its offspring lies in the jaws of others.
18:33And the crucial element of success comes down to who is doing the eating.
18:41Something the tree has no control over.
18:46Many seed pods are doomed before they even hit the ground.
18:52These round holes are the work of the bruchid beetle.
18:58It lays its eggs directly onto the pod's outer casing.
19:04The newly hatched larva burrows its way inside and starts eating.
19:12By the time it re-emerges, all fattened up, there's little left but a potholed, empty husk.
19:25The remaining healthy seeds have caught the eye of a ground squirrel.
19:34But the squirrel's teeth and jaws are just too strong.
19:39And they grind down the pods.
19:43Husk, seeds and all.
19:47Turning any chance of a new seedling into dust.
19:55But there is one set of animals in the desert that can help the acacia.
20:01This grey duiker is a welcome diner.
20:06A portion of the seeds will safely pass through its four stomachs unharmed and reappear ready to be planted.
20:17Dikers, along with hemsbock and springbok, are the acacia woodland's salvation.
20:27And the seeds are an important food source for them during the long periods of drought.
20:34As they continue their search for food, they scatter the unscathed seeds far and wide across the desert.
20:44Planting the next generation of tough little trees to preserve this rare forest in the unforgiving Kalahari.
21:05If a tree can't tempt an animal to eat its seed, it must come up with an alternative solution.
21:12One tree in particular has taken their unusual dispersal strategy to a lethal level.
21:2680 kilometres off the coast of southern Australia
21:33lies Lady Elliot Island.
21:39In the heart of the Great Barrier Reef, this coral kay island is one of the few that supports its
21:48own forest.
21:57Just one species of tree has managed to get a foothold here.
22:02The Pisonia grandis.
22:06An entire forest sprung from a few deposited seeds.
22:13But on such a tiny secluded island, once the forest has reached capacity, how does it expand into new lands?
22:27The nearest island is over 35 kilometres away.
22:32Too far for the seeds to be transported on the wind, and they won't survive in salt water.
22:41The trees need a seed carrier.
22:50During the summer months, this forest plays host to some 50,000 migratory seabirds as they flock to this island
23:00to find a mate.
23:06The trees offer an attractive site to build a nest.
23:11At over 20 metres tall, they provide shade and a protective buffer against the winds that batter the coastline.
23:23But it's a small forest, and there are many seabirds.
23:30Over 40 pairs of noddies may nest in a single tree.
23:37In return for acting as hosts, the seabirds gift the trees tons of nutrient-rich droppings.
23:50On a sandy coral island, it is this guano that sustains the forest and fuels its growth.
24:02It's a match made in paradise.
24:07And these long-distance seabirds make the perfect seed carrier.
24:12They can fly from island to island and spread the Pisonia's influence throughout the archipelago.
24:22But this is where the plan hits a snag.
24:28Seabirds don't eat fruit or seeds.
24:32So the tree has to find another way for the birds to carry its offspring.
24:40Glue.
24:43The Pisonia coats its seeds in a sticky substance.
24:48Strong enough to hold firm on the birds' feathers whilst flying over the sea to another island.
24:56But weak enough, so the seed eventually drops off in its new home.
25:06However, in their ambitious quest to colonize new islands, the tree has gotten overzealous.
25:16And its dispersal strategy has spiraled.
25:24The trees produce so many sticky seeds that they often smother the birds.
25:35With their feathers glued together and loaded down with seeds, they can no longer fly.
25:47The forest is unwittingly sabotaging its own expansion plan.
25:55So far, few trees have managed to sprout on other nearby islands.
26:03This remains the only forest for kilometers.
26:09So they keep returning to this one island, despite the toll.
26:17The forest and bird are stuck on an evolutionary path that's hit a dark, dead end.
26:40When forest and animal do work in harmony,
26:43the results can bring a secret sweet relief to life in a bitter landscape.
26:51There are very few species of tree that can survive in Australia's brutal interior.
27:02Even the tough eucalypts have failed to conquer these lands.
27:11Again, it is an acacia forest that dominates this desert.
27:21This Australian species is known as the mulga tree.
27:30Hardy and efficient, it is one of this arid zone's most successful inhabitants.
27:36Partly due to its own partnership with not one, but two insect species.
27:45The tree's branches are sprinkled with lerps.
27:50These crystallised honeydew bubbles protect juvenile psyllid bugs that live off the tree's sap.
28:00Patrolling between the lerps is the honeypot ant.
28:05They won't harm the psyllids.
28:08But instead, they drink the honeydew encased within the protective shells.
28:16Diligently, the ants bring supplies of this sweet nectar back to the nest,
28:22located at the base of the mulga tree.
28:28Down here, in their underground network of tunnels,
28:33the ants stockpile their precious elixir for when times are lean.
28:43The honeydew is kept in living larders that hang from the burrow ceiling.
28:53Specialist ants, known as repletes, are overfed with this syrup
29:00until their dangling, extended bellies stretch to bursting.
29:10These are the eponymous honeypots.
29:16When the desert drought reaches extreme measures,
29:20the worker ants stroke a replete's antennae
29:25and receive a ration of the sugary liquid.
29:35The mulga tree sustains the ant colony through tough times.
29:42And in return, the ants help the tree to thrive.
29:48Honeypot ants act like earthworms in the Australian desert.
29:53They till the soil,
29:56recycling valuable nutrients
29:58and breaking down organic matter.
30:04Their burrows act as funnels,
30:06transporting precious drops of rain straight to the tree's roots.
30:15In the unpredictable and extreme nature of the Australian outback,
30:19this two-way relationship between insect and tree
30:26enables both to survive where little else can.
30:41As we walk through any forest, we can be unaware of the extreme nature
30:47of what lies just beneath our feet.
30:52In broadleaf forests, down amongst the layers of fallen leaves and broken tree trunks,
31:01lies a world that is rotten to the core.
31:13This is where hidden terrors live.
31:18This is where hidden terrors live.
31:29and no-one is safe.
31:36This giant centipede in New Zealand can only survive in a moist environment.
31:44So the damp forest floor is his chosen realm.
31:50At 20 centimetres long, it is the stuff of nightmares.
31:57It's pincer-like legs that move in a hypnotic rhythm.
32:04The fact it has eyes, but can't see.
32:13It's killer instinct.
32:19The skink is safe.
32:23As long as it stays still.
32:27The centipede can't see it, but it can detect movement through its antennae.
32:35Do.
32:38Not.
32:40Move.
32:53The centipede subdues its victim,
32:57before using its specially adapted front limbs to inject it with venom.
33:06Having feasted on its innards,
33:12The centipede returns to its darkened lair until it's time to hunt again.
33:23In this underworld, nothing is what it seems.
33:34Perfectly camouflaged against the forest floor.
33:38This is a Brazilian wandering spider.
33:46This spider doesn't build a web to wait for her food to arrive.
33:50She goes out and hunts.
33:54And she uses the leaf litter to help her.
34:00Her fangs are packed with the most potent venom of any spider in the world.
34:06And her legs can detect the slightest vibration from several meters away.
34:14So if any hiding insect rustles a single leaf...
34:25It's game over.
34:29But as these mini-monsters consume their next victims, they are helping the forest deal with its litter problem.
34:40A build-up of dead leaves could choke a forest.
34:45All this leftover organic matter needs to be reduced and recycled.
34:52Whilst the fungi and bacteria living in the soil take on the bulk of the decomposing work...
35:05Spiders prop up the process by hunting the insects that eat the fungi.
35:13And also supporting this vital service is a very specialist band of invertebrates...
35:18known as the detritivores.
35:24Each member has its own role to play on the forest floor.
35:32Millipedes feast on the tougher leaves, breaking them down for the microorganisms to recycle.
35:41Leaf-cutter ants use their mandibles to cut up discarded fruit and carry huge loads back to their nest.
35:48To feed their fungi farms.
35:55Veracious grubs chew through the dead wood...
36:00Accelerating its decay and returning its nutrients to the soil.
36:08Where it continues to fuel the forest.
36:13These hard-working critters are paramount to the success of our forests worldwide.
36:21By keeping the soil healthy and reworking every nutrient...
36:27Woodland ecosystems simply could not work without them.
36:40A healthy, fully functioning forest can be a powerful force.
36:46It can influence our climate, support life...
36:50And even...
36:53Cover up our remains.
36:56As humans, we have undoubtedly left our mark on this world.
37:02But those marks are not always indelible.
37:08So what happens when we're not there to maintain our dominance?
37:14Over time, nature returns to take back what is rightfully hers.
37:25This former prison on Gorgona Island off the coast of Colombia...
37:31Detained some of the country's most notorious offenders.
37:36But 40 years after the last inmates left...
37:41The surrounding forest has reclaimed the area.
37:51Trees need to expand in order to grow.
37:56Its living tissues simply flow around and engulf anything in its way.
38:03Binding itself to man-made structures...
38:06Until the two become one.
38:11The forest gradually swallowed the buildings.
38:17And the wildlife returned.
38:25This process of ecological succession...
38:30Is when nature is allowed to follow its own path...
38:35And regenerate an entire environment.
38:41Across the globe, wherever humans move out...
38:45Fast-growing, pioneer species of trees move in.
38:51In just a matter of years, empty urban spaces...
38:55Revert back into forests.
39:00Drawing in...
39:02A different set of residents.
39:22In the face of human encroachment...
39:25Life always finds a way.
39:30Even a forest full of man-made ghosts...
39:34Can create a life worth fighting for.
39:43This forest in Yala National Park in Sri Lanka...
39:48Was deliberately flooded by residents...
39:51About eight years ago.
39:57The trees...
39:59Slowly and silently...
40:01Drowned in the newly created lake.
40:09Preserved in the salt water...
40:11They remain upright.
40:15Stripped bare and knee-deep in the water.
40:21But a lifetime's worth of nutrients...
40:24Once stored in their trunks...
40:27Now leeches into the water.
40:33Even as a ghost forest...
40:35The trees have created...
40:38A surprisingly fertile habitat.
40:45Meaning it's still hot property for many animals.
40:54And for a bird of prey...
40:57It's the perfect forest.
41:02This juvenile white-bellied sea eagle...
41:05Recently left his nest.
41:07And is now looking to establish...
41:10His own territory.
41:13And these ashen skeletons...
41:16Will suit him very nicely.
41:20The rigid branches support his weight.
41:23And the lack of leaves and twigs...
41:26Is far more accommodating...
41:29Of his two-metre wingspan.
41:33There is no requirement...
41:35For a leafy canopy to hide from predators.
41:38He is the predator.
41:43And he has a clear line of sight...
41:46To pick out a target from the lake below.
41:55But if he wants to claim...
41:57This highly desirable area as his own...
42:00He is going to have to fight for it.
42:07A rival young male...
42:09Has also set his sights...
42:10On this forest graveyard.
42:15So he attempts to run this new arrival...
42:18Out of town.
42:27In an effort to throw off his pursuer...
42:30The trespasser lets go of the fish.
42:35But this isn't about food.
42:37This...
42:39Is a battle for real estate.
42:43This is a battle for real estate.
42:57When his competitor drops out...
42:59The new arrival...
43:01Chocks up a win.
43:05But his victory lap does not last long.
43:12The young eagles have failed to realise...
43:15They are squabbling over a territory...
43:18That is already taken.
43:22By these resident adults.
43:29With far superior flying...
43:33And fighting skills...
43:36The fully grown seagulls...
43:38Have secured this coveted spot...
43:40As their own.
43:43And they are not prepared to share.
44:08The youngster will fare better...
44:11In a less competitive neighbourhood.
44:18Even a drowned forest...
44:20Is a useful one.
44:21Of their own...
44:23These grey ghosts...
44:24Still have a huge ecological value...
44:27To the surrounding wildlife.
44:31And competition...
44:32To call them home...
44:34Is just as rife...
44:35As in a living forest.
44:49Υπότιτλοι AUTHORWAVE
45:07Υπότιτλοι AUTHORWAVE
45:37Υπότιτλοι AUTHORWAVE
45:42Υπότιτλοι AUTHORWAVE
45:47Υπότιτλοι AUTHORWAVE
45:47που έτσι χρειάζουν, όταν ήρθαν,
45:50επίσης χρειάζοντας χρειάζοντας.
45:53Υπότιτλοι AUTHORWAVE
45:55Υπότιτλοι AUTHORWAVE
45:56και η φορή αρκετή αρκετή αρκετή,
46:00σε ένα νοημένο σημείο.
46:02Συμπέντες από σαπλή.
46:06Συμπέντες, η φορή αρκετή αρκετή αρκετή αρκετή,
46:11μεταφεύει 15 χλμ.
46:26Υπότιτλοι AUTHORWAVE
46:46Υπότιτλοι AUTHORWAVE
47:14As we lose our forests, we lose a huge ally in the battle to slow the warming of our planet.
47:22Over millennia, they have fought to thrive in every environment, however extreme.
47:29But the limits to those extremes now lie in our hands.
47:37If allowed, our precious woodlands can continue to work their magic, shape our world, and nurture all life within them.
47:51We'll be right back.
47:55We'll be right back.
47:59We'll be right back.
48:00We'll be right back.
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