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00:10Savannah, pampas, prairie, meadow, even lawn, grassland goes by many names.
00:26Seas of green dominated by one of the most dynamic and successful plant species, grass.
00:36It's so hardy and productive that it can survive flooding, drought, fires, and still feed vast
00:54and hungry animal communities.
01:05Many of nature's most dramatic spectacles occur in this breathtaking wilderness.
01:11The open, endless, and enduring grassland.
01:20Most of us are familiar with the properties of grass.
01:24It's hard wearing and fast growing.
01:27In our gardens, we seem to cut it constantly, and it appears to thrive on this apparent abuse.
01:34It's a plant that does better under pressure.
01:41And it certainly faces plenty of that.
01:51The grasses of the Serengeti and Maasai Mara host the biggest event in the natural history
01:57calendar, the migration of some two million wildebeest.
02:02As the rivers of Northeastern, we see the wildebeest.
02:31As the rivers of life
02:32pour across the plains, they are followed by some of the most iconic creatures on Earth.
03:20As the rivers of life
03:36It's the stage for nature's greatest spectacles.
03:44All of these great animals that define the plains are totally dependent on one thing.
03:53The grass.
03:583.5 billion hectares across the globe are covered by grassland, 40% of the land surface.
04:07Despite their success, grasses are relative newcomers to the plant community.
04:14Fossilized dinosaur poop reveals the grasses first appeared during the Cretaceous period
04:20and might have fueled the evolution of the great beasts themselves.
04:27But it was much later, when climate change brought a reduction in forest cover around the world,
04:33that grasses were poised and ready to take over, colonizing every continent apart from Antarctica.
04:44Some people define grassland as a halfway house between forest and desert.
04:50They exist in areas that don't get enough rain for forests to grow,
04:55but have enough to prevent deserts from forming.
05:02And it's seasonal rains that drive animal migration.
05:08The plains of East Africa, the Masai Mara and Serengeti, are tropical grassland, known as savannah.
05:18It thrives only where there is enough rain,
05:21usually between half to a metre and a half of water a year,
05:25and often all coming at once during a rainy season.
05:39using Parkland, which means how to procent massive ripc殖.
05:40It's really bad who's discovered a lot of dusting...
05:41A faim poisonousedelic straw that hits the part to the坑 seen.
05:45This girl is done and afteranging up on the ground next.
05:47And it's not really well everywhere,
05:53it's really better for us and avenues!
05:59To manage either
06:03This replenishes the plants and animals.
06:40And by storing water in their leaves and roots, the grasses will act like a sponge, holding
06:47on to some of the moisture during the dry season that's yet to come.
06:57The replenishing rains trigger the breeding season, a baby boom on the plains, new lives
07:09starting out, ready to exploit the bounty.
07:16The young grazers must get to their feet quickly.
07:20They'll need to follow the endlessly moving herds.
07:30They'll grow fast on the lush, new plant growth.
07:34But their sudden abundance will also feed them many new arrivals for predatory parents as
07:41well.
07:59So what are they going to do?
08:11They're like, oh, my God.
08:28The circle of life supported by savannas.
08:44Not all grasslands get water from rain.
08:53Parts of the Asian steppe can become bitterly cold.
08:58The Eurasian steppe is a vast grassland spanning from Hungary to China, almost a fifth of the
09:05way around the world.
09:08It's been a major trade route for people between Europe and Asia for centuries, but had long
09:15distance travellers way before that.
09:21The steppe once hosted giant herds of gazelle, horse and camel that migrated in numbers rivaling
09:28the plains of Africa.
09:30The grassland here is cold and dry, receiving less than 50 centimetres of rain a year and
09:37with winter temperatures that can plummet below minus 50.
09:43The extremely cold, dry air has brought about bizarre adaptations in one of the plains' antelope.
09:55The extraordinary snouts of saigas are air conditioning units, taking in the freezing desert air, warming
10:02it and adding moisture to it before it's inhaled into the lungs.
10:10The male's appendage seems particularly impressive during the breeding season, perhaps helping
10:16to amplify his calls.
10:22For the cold winters, the herds gather in large numbers and migrate to the most forgiving areas.
10:32The migration might take them over 1,000 kilometres, disturbing the resident hares.
11:01But as the steppe warms up, they break into smaller herds and they return to their summer
11:07feeding grounds to breed.
11:10When they are ready, the heavily pregnant females gather and synchronise their births to try
11:16and reduce the impact of predators on their numbers.
11:33mums immediately encourage the little fawns to their feet with enticing milk.
11:45even in a crowd, they will recognise one another's scent and calls.
11:57The babies need to quickly get their legs working, ready to join the herd for a life of nonstop walking.
12:21After a bit of walking practice, the fawn instinctively knows to lie low while its mother goes off to feed.
12:37After a few days, the herd gets restless.
12:41The male rounds up his girls and offspring to get the herd back on the move.
13:13grasslands are among the richest habitats on earth.
13:16teeming with the greatest concentrations of big gain, though most of its riches lie beneath their feet.
13:24grasses were an evolutionary breakthrough.
13:27grasslands grew.
13:28Unlike most plants coming before them that grow from their tips, grass grows from its base.
13:36It means plant eaters can munch away on the leaves without killing the plants.
13:44grasses were able to put up with the grazing of dinosaurs, so cope well with the passing herds.
14:10savannah covers almost half of the African continent, but isn't limited to Africa.
14:24It's found in other countries, such as India.
14:31It's found in other countries, such as India.
14:32Parts of South America.
14:40Australia.
14:40And Australia.
14:48In all regions, it supports large animals.
14:53In Australia, antelope herds are replaced by kangaroos and other large marsupials.
15:07savannah is the grassland produced by warm places with distinct wet and dry seasons.
15:14But grasslands have colonized a much more diverse range of climates.
15:20There are tough tundra grasses, able to survive the frozen soils and short growing seasons.
15:27These once fed ice age mammoths.
15:41And there are grasses that take flooding in their stride, like Pantanal of the Amazon basin.
15:49As water runs off the Andean mountains and flows into the Amazon basin, adding to the region's heavy rains,
15:57it causes water levels to rise by up to five meters, submerging the grassland for several months of the year.
16:11But there's another type of grassland that's much more familiar to most of us.
16:18Temperate grasslands go by several names, often called meadows in Europe.
16:31And here, in North America, it's known as prairie.
16:43When plate tectonics thrust up the rocky mountains, they created a rain shadow.
16:49The moisture from the ocean fell when it hit the mountains and no longer drifted further inland.
16:57It meant Middle America became too dry for trees, and so the vast Great Plains of America were born.
17:07800,000 square kilometers, an area the size of France.
17:13The realm of westerns, where cowboy and Indian dramas played out,
17:18was once one of the most productive landscapes on earth.
17:22Like all temperate grasslands, the prairie has a less defined rainy season.
17:29Instead, it's typified by hot, dry summers and very cold winters,
17:35ranging from plus to minus 40 degrees centigrade.
17:43Herds of big game have always migrated across these grasslands to make the best of the seasons.
18:01Their diversity is not as great as on the tropical grasslands.
18:06But their sheer numbers were perhaps the greatest concentration of mammals on earth.
18:16The dominant feature, more than 25 million bison.
18:36European settlers on the continent all but wiped out the bison.
18:43They are not as great as on the planet.
18:44They are not as great as on the planet.
18:44They are not as great as on the planet.
18:45But in their heyday, they defined the plains.
18:50Slowly, they are making a comeback and thrive on the rich grasses.
18:57The presence of these giant grazers might seem like a threat to the plants.
19:02But grasses benefit from them.
19:06The plant eaters crop the plants low to the ground.
19:10It takes other species a while to recover.
19:13But growing from their base, the grasses are quickest to recover.
19:18Because bison tend to graze heavily on some patches and move on, and because they target the grass,
19:25they also create opportunities for other species to seize their chance.
19:30Creating a greater diversity, a patchwork of vegetation.
19:40Where they wallow and roll, they make shallow depressions in the soil.
19:48Sheltered from the wind, they are damper and provide mini-habitats for yet more species.
19:57As they roam, the great beasts stir up insects.
20:02And so have an entourage of feathered friends keen to snatch the fleeing bugs.
20:30On grasslands around the world, many birds have a close association with big-game animals.
20:36And follow the herds to enjoy insects they stir up.
20:40And even plucking parasites, like ticks, directly from the animals' backs.
20:48None are more devoted to their grooming than the African ox-peckers.
20:54For a long time, it was presumed that ox-peckers are the bigger mammals' best friends.
21:01The little birds work over their bodies, combing the fur and consuming up to 100 ticks a day.
21:10Like woodpeckers, they have a stiffened tail to lean back on while they work,
21:15and two toes forwards and two back to improve their grip.
21:21But they might not be as friendly and helpful as we first thought.
21:25New research suggests that the birds don't like the ticks as much as the host's blood that the ticks are
21:32filled with.
21:33And the birds are just as happy to peck at the animals' wounds to cut out the middleman and get
21:40blood straight from the source.
21:45Ox-peckers are bloodthirsty vampires.
21:51But the fact remains that in the long grass, ticks are abundant.
21:56Just one of thousands of insect species on the plains.
22:05The big mammals are the ones we tend to notice.
22:10But in terms of bulk, all of the grassland's insects would outweigh all the mammals combined, including all the elephants.
22:28Perhaps the most numerous, both in terms of numbers and mass, are termites.
22:34The tiny creatures, through their sheer mass and tireless construction, are landscape engineers.
22:43They dig through the soil, aerating, circulating nutrients and improving drainage.
22:54Some build giant mounds, and these create oases, areas of shade and moisture that benefit other plants and animals.
23:05They are the ultimate recyclers, eating dead leaves and fallen wood, helping to break it down and return its nutrients
23:13to the soil.
23:15At least they try to, though the Australian echidna has other ideas.
23:29The colonies are made up of millions of blind workers, using chemical trails to communicate and follow each other.
23:38But sometimes, different termites are born, not workers and not blind.
23:46These are alates, winged warriors, ready to go forth and start colonies of their own.
23:56And when they emerge to fly, they are greeted by many other creatures of the plains.
24:04Because not only are termites good for the environment, but they are packed with fats and proteins,
24:10a much appreciated food source for many.
24:24Bishop birds, kestrels, even colourful rollers flock to the feast.
24:36Clouds of swallows use the bugs to calorie load ready for their migrations.
24:48There are even a few bigger animals that get in on the act.
24:58Africa's famed for its predators, but the smaller ones are often overlooked.
25:05The serval is a secretive member of the lynx family.
25:09His radar-like ears can hear the scurrying insects.
25:14Though he'll tackle most small prey, he has a speciality, and it's not bugs, it's birds.
25:28When the termites fail to fill his stomach, he can turn on some of the other diners.
25:39With radar ears to pinpoint prey, he can triangulate the distance and then use long legs, the longest in relation
25:48to size of any cat, to spring three metres into the air.
25:59Birds are abundant on the plains, and with such rich resources, some have become giant ground dwellers to roam among
26:08the herds.
26:10The biggest bird of all, the ostrich, towers over most of the antelope.
26:16In fact, the mammals like these lofty companions because, with their height advantage, they are quick to spot danger.
26:53The
27:01grassland living is so productive that it fueled the evolution of a whole family
27:11emus strut across the plains of australia
27:24and rears the south american pampas
27:39though these ones are immigrants escapees who have established themselves on farmland in germany
27:49without the benefit of flight they must nest on the ground
27:53using grass to hide their eggs
28:13some of the grassland giants can still fly but only just
28:19there are 26 species of busted including the heaviest flying birds
28:26cori and giant bustards can weigh 20 kilos
28:31the strange birds have elaborate courtship displays using fans of feathers to help them stand out across
28:37the plains
28:40and unique booming calls low frequency to travel further over the grassland
28:49like ostriches they walk everywhere feeding on seeds and insects
28:55they even nest on the ground but when danger threatens can retreat to the skies
29:03the fact that these giant birds thrive here is testimony to the abundant food especially insects
29:14insects are vital to the health of grasslands
29:20not only for the soil's health but also for supporting the base of the food chain
29:35they are the biggest consumers of plants and many plant species are dependent on the insects to pollinate them
29:43they're not the grasses themselves most of them produce pollen that's released into the breeze to hopefully land on
29:51and fertilize neighboring grasses
29:58the insects are also pretty important for tidying up
30:03the bigger inhabitants produce a lot of waste
30:08but there's a fleet of insects waiting in the wings to clean up after them
30:17dung beetles are tireless workers loading up balls of dung to cart away
30:26they're not working for free their fee is to feed on the dung and use it as a nursery to
30:32hatch their eggs in
30:35but in rolling it off and burying it they are distributing the nutrients throughout the soil
30:46the soil
30:47despite their hard work insects aren't treated with much respect just about everything eats them
30:55but they also face a far greater threat
31:03rain isn't the only major factor that shapes this landscape
31:11thunder cracks as storm clouds build towards the end of the dry season
31:17the ground beneath and the plants on it are parched
31:25it's a tinder box
31:28and it doesn't take much of a spark
31:42and it doesn't take much of a spark
31:43warm winds help wildfires spread at a terrifying speed
32:06large animals can run from the inferno
32:14but smaller slower creatures will perish in the flames
32:33it's hard to imagine a force that appears more destructive
32:38but fire is an ancient and vital part of the health of grasslands
32:50without it leaf litter piles up over the ground
32:54it takes years to break down and release its nutrients
32:58and the layer blocks out the light making it hard for new plants to grow and get to sunlight
33:06the fires strip it back clearing the ground
33:11it also takes out shrubs preventing woodland from developing on the plains
33:22animals have long lived with fire some have even learned to exploit it
33:29it's hard to catch the insects
33:31kites soar along the front line waiting to swoop in and catch the insects as they flee before the flames
33:45they have even been reported to pick up burning branches and drop them elsewhere helping to spread the flames
34:00and marabou stalks and baboons follow the fire's wake collecting the barbecued bodies
34:16the scorched landscape looks like a wasteland
34:20a charred mass graveyard
34:28but the fire has converted the slow to rot leaf litter into ash
34:34an ideal fertilizer for plants
34:37and it's cleared the ground
34:39the sunlight can warm the soil
34:41fueling microbial activity which breaks down the ash in the soil
34:45fueling plant growth
34:48and now the new shoots of direct sunlight
34:55within days fresh green growth returns to the plains
35:04because grass grows from its roots
35:07it can quickly re-sprout
35:11the grazers move into recently burned areas for the lush new shoots
35:16the fires also level the playing field giving other species the chance to grow
35:21often from dormant seeds or tubers in the ground
35:38when the rains arrive it doesn't take much for the brown past grassland to become a kaleidoscope of color
35:48as well as it is
35:49painterly masterpieces
35:50brought about by the two essential forces of fire and water
36:02fire drives diversity
36:05and not just of plants
36:10areas that have regular burns can support 30 percent greater mammal diversity
36:16and 40 percent more variety in their bird populations
36:23though fires have been a part of natural landscapes for eons
36:27they played an even greater role in the shaping of grasslands because of people
36:35long before farming hunter-gatherers would set fire to the bush so that they could hunt just like the kites
36:43do
36:44catching the animals fleeing from the flames and to attract big game to the fresh growth afterwards
36:51across the world people have played this role in grasslands for millions of years
36:58today fires are still set but more to clear land for farming and to encourage fresh growth for livestock
37:06there are still humans specialized for a life on the grassland
37:10plains people including the aborigines and native americans and also these maasai pastoralists in east africa
37:19they live semi-nomadic lifestyles instead of following the migrating game as our ancestors did
37:25they leave their cattle to fresh grazing
37:43when humans domesticated both plants and animals it was to change the world and grasslands in particular
37:53today most of the grasslands we see are ones modified by us
37:59be it garden lawns parks sports grounds or most often sprawling farmland we have harnessed the power of
38:10grasslands and grasses to feed the world domesticating cereals and growing hay for our livestock
38:24so
38:25some of the cultivation has been going on for so long
38:28more than 10 000 years that wildlife has adapted to the altered landscapes
38:35the lush meadows cultivated for cattle feed are a powerful draw to wild grazers
38:45Deer emerge from woody edges of the fields to enjoy it, and the meadows support hares
38:52and rabbits.
39:04Different species of grasses are grown for different produce.
39:08In Asia, rice has been the mainstay for at least 13,000 years, and the wet meadows it requires
39:16provide attractive habitat for fish, frogs and insects.
39:31Much of the rest of the world is dominated by cereals like corn, wheat and oats.
39:39Across the world, half of all calories consumed by people come from farmed grasses.
39:56Selectively bred for maximum yield, the grasses produce big seed heads, rich food that's too
40:04tempting to wildlife.
40:09Game birds like pheasant and quail skulk around between rows of crops.
40:17And the nutritious grains are a magnet to rodents.
40:22A hamster family lives under one field.
40:28A mother gathers the cereals in her cheek pouches, her built-in shopping bags, so she can ship
40:34food back in bulk to her burrow and hungry litter.
40:56With such a high-calorie diet, her family, and many others like it, will grow fast on farmland.
41:11Though living here is not without its risks.
41:19Wild meadows are grown so that they can be harvested and stored to feed cattle and other livestock
41:26through winter.
41:27So periodically, the animals experience disaster.
41:37And crops are harvested for human consumption.
41:40With heavy-duty machinery, the fields are suddenly not such great places for animals to hide their
42:02young.
42:04Even once the habitat's been turned upside down, there are animals that have learned to take
42:10advantage of the situation.
42:14As birds follow large mammals on the plains to feast on the insects they kick up, so
42:20too do birds follow tractors.
42:23The white storks will pick up any creatures rendered homeless by the harvest.
42:42Wildlife rarely gets a free ride.
42:48One of the advantages of creating lush pasture is that it attracts plant eaters.
42:54plants, and humans have long exploited this to stock their larders, shaping the land to provide
43:00all the food they need.
43:08Despite the challenges, farm fields have been important for so long that thousands of species
43:15have adapted to them and now can't live without them.
43:18them.
43:20But rural idylls are increasingly rare.
43:29Most farms operate on an industrial scale to meet the demands of the growing human population.
43:39For maximum yield, meadows are cut more often, not allowing wild plants and animals to complete
43:46their life cycles.
43:55countryside birds are disappearing because they are losing the chance to raise their young.
44:10To maximize yields, hedgerows have been cleared and crops are sprayed with pesticides to kill off insects, and artificial fertilizers
44:20to replace nutrients lost
44:22from the soil, so they can be farmed over and over.
44:29Poorly managed soils lose 70% of the carbon stored in it, fueling the climate crisis.
44:40And right now, a third of all global soil is degraded.
44:47Up to 40 billion tons of soil is being lost every year to erosion, reducing its productivity, carbon
44:55storage and cycling of water and nutrients.
44:58One inch of soil can take 500 years to develop, making it an unsustainable resource.
45:07Grasslands are becoming monocultures of single domestic species and no longer provides the habitat countryside
45:15wildlife needs, no feral wildflower meadows here.
45:22Many species of countryside birds, insects and other wildlife, that were common sites just a few decades ago, are racing
45:30into oblivion.
45:37And though grasslands can occur naturally, the need for produce to feed the growing human population as it approaches 8
45:46billion requires the cultivation of more and more land.
46:02Now rainforests are clear cut to open them up to graze cattle and grow soy as cattle food.
46:15Landscapes that were lush and green sources of water and carbon stores are being opened out where they quickly lose
46:22their fragile soil and become hot and dry.
46:25These changes impact global weather for natural grasslands and the rest of the world.
46:42Though big herds of grazing animals have always been a feature of the plains, humans crowd far more animals onto
46:49the land than it can support and don't allow natural migrations.
46:54So the goodness in the soil is quickly exhausted.
47:00All the wild ones, all the whales, elephants, bears, vast herds of wildebeest combined would only weigh 4% of
47:11the weight of all mammals on earth.
47:1596% is humans and our livestock, particularly cattle.
47:22The rearing of meat on this scale is not sustainable.
47:25And changes in human diet are essential to build a healthier world for the future and to ensure the grasslands
47:34can endure.
47:37Out of the nearly 4 million square kilometers of the great American prairie, only 2% remains natural.
47:47A pattern repeated across the world.
47:50And the animals have vanished too.
47:54The great herds of bison that compacted and fertilized the soil.
47:59The elephants of Africa that shaped the landscape, clearing woodland and maintaining open savannah.
48:06Without them, natural ecosystems fail.
48:09We are throwing away biological treasure, but also a powerful friend.
48:17Grass improves air quality and disperses heat, protecting the ground and anchoring the soil together.
48:27Just a tablespoon of rich soil can contain more organisms than there are people on the planet.
48:35More than 10,000 species.
48:38And of course, grass produces oxygen and locks away carbon.
48:47A football field can produce enough oxygen to sustain 12 people.
48:52So it's making enough for at least one of the teams to breathe.
49:03Whether it's the Great Plains, roadside verges or our own backyards, we need this precious resource.
49:12And so does wildlife.
49:20For their sake and ours, it's time to celebrate and protect our glorious grasslands.
49:47For our sake and our soul, offense, and protect our agents and our backyard life.
49:59And it's just a mereницаfolk is alive at night.
50:00For the heavenly lovelyness you may enjoy and protect our ancestors.
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