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Documentary, Nature's Biggest Beasts
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AnimalsTranscript
00:00The gigantic giraffe boasts some impressive stats.
00:21It's the tallest mammal on earth, nearly three times the height of a professional basketball
00:29player. And as heavy as a car. But have you ever considered what it takes to feed such a massive
00:39frame? Or how this giant overcomes the rather difficult problem of drinking?
00:59Being one of Earth's big beasts has its advantages, but also comes with sizable challenges.
01:13How they overcome life's big problems can be truly jaw-dropping. Whether it involves a total meltdown,
01:21a brutal battle, or maintaining their own air conditioning, it seems they've got it licked.
01:41It's time to meet a remarkable group of animals. Nature's biggest beasts.
01:48From the behemoths of a bygone age. To the leviathans of our modern world. It's the biggest beasts
02:01that capture our imagination.
02:08But size is relative. And there are surprising giants lurking in places you might not expect.
02:15Animals whose claim to fame is simply being amongst the biggest of their kind.
02:22But whether they're a titan in a tiny world, or a giant among other giants, they all share
02:28the same basic challenges. Moving their massive bodies.
02:31Moving their massive bodies. Surviving extreme temperatures. Having huge babies.
02:35Having huge babies. And not least, the need to eat. A lot.
02:42And not least, the need to eat. A lot.
02:49And not least, the need to eat. A lot.
02:55Let's begin with an incontestable big beast.
03:20Those giraffes.
03:27Nearly six metres of mostly leg and neck. Perched on feet the size of dinner plates.
03:45Being head and shoulders above the rest does have its perks.
04:04Being for miles around.
04:15Reaching 35 miles an hour with its ground eating strides.
04:19And of course, 1.8 metres of neck and an extra 50 centimetres of tongue means it can reach the food its competitors can't.
04:37Just as well. Because a giraffe has a super-sized appetite.
04:52Which it needs to satisfy by eating foliage.
04:58To get enough nutrients from just a few leaves per bite, a large male must consume up to 65 kilograms daily.
05:13To eat through that many leaves a day can take up to 18 hours.
05:19But never mind feeding.
05:28In dry times, a giraffe can need up to 38 litres of water every few days.
05:34But how to get it, when it's seemingly so hard to come by?
05:39Well, it has a neat trick.
05:44By eating at dawn when condensation is high, it can absorb most of its moisture from leaves.
05:52It also wastes no water sweating or panting.
06:07Instead, its temperature fluctuates with the surrounding air.
06:11But when beaten by the heat, giraffes must join their fellow beasts at the watering hole.
06:28Being tall, it's tricky.
06:35In this pose, the pressure is, quite literally, on.
06:41Pumping blood against gravity up to the head takes a powerful heart.
06:54It beats up to 170 times a minute.
06:57That's twice as fast as ours.
07:11This huge blood pressure, the highest of any mammal, should give a drinking giraffe a bad head rush.
07:24But instead, a clever system of valves regulates blood flow to the brain.
07:29The giraffe controls blood pressure so well that NASA has taken inspiration from these humble goliaths for the design of its spacesuits.
07:47It seems this big beast can even teach us a thing or two.
07:57The unique physical characteristics of a giraffe allow it to feed with relative ease.
08:15Many big beasts, though, have to fight for their food.
08:28This remote Indonesian island is home to an illustrious lizard.
08:33It owes its prehistoric good looks to its age.
08:48It's one of the few living species to have been around for over three million years.
08:53The Komodo dragon.
09:06Earth's largest lizard.
09:13Big enough to hog a king-sized bear.
09:17And then some.
09:32Despite their intimidating credentials, these dragons don't have it easy.
09:38Around 6,000 remain, making them vulnerable to extinction.
09:50To add to their woes, these ferocious beasts have, for their size, a bite that is weaker than that of the average house cat.
09:59Their survival, though, relies on satisfying their insatiable hunger.
10:18These dragons have set their sights on this buffalo.
10:22At ten times a dragon's size, it's a very dangerous dinner option.
10:39One well-aimed kick, and a dragon could die hungry.
10:43So how does a Komodo, with its measly nip, take on such a formidable adversary?
10:56Its bite may be weak, but it's bolstered by around 60 backward-facing serrated teeth.
11:03The grip, and rip-bite.
11:04The grip, and rip-bite.
11:05The grip, and rip-bite.
11:10The grip, and rip-bite.
11:29On prey this size, it just draws a bit of blood.
11:33It's more deadly than it looks, though.
11:45The bite has set the dragon's next weapon in motion.
11:51Tucked either side of this lizard's weak jaw, a venom glands.
11:55A bite releases the poison, preventing the prey's blood from clotting.
12:13Stage two takes days, and days, of patience.
12:18The buffalo's wound is not healing.
12:42Three weeks later, and it's finally time to eat.
12:48These ravenous reptiles can polish off 80% of their body weight in a single city.
13:09No energy gets wasted on chewing, either.
13:12A tube running from the base of the tongue to the lungs, means a dragon can breathe while it swallows each mouthful.
13:20In one.
13:21This combination of clever adaptations means this big beast can take down even bigger beasts to satisfy its need to eat.
13:27and ensure its survival.
13:28This combination of clever adaptations means this big beast can take down even bigger beasts to satisfy its need to eat.
13:34Adaptations means this big beast can take down even bigger beasts to satisfy its need to eat, and ensure its survival.
13:44Enormous appetites have led many sizeable species to target prey that should be out of their league.
14:09And the big bugs of the undergrowth are no exception.
14:17Imagine an insect that's big enough to take on a bird.
14:28Meet the Kalahari's armoured ground cricket.
14:39This hulk of the insect world puts its tiny European cousins to shame.
14:48As an omnivore, it eats plants, insects and crops.
14:53But there's one more thing it really needs.
15:02Red-billed Quilia follow the rain, gorging on crops that spring up in the now fertile ground.
15:08They're feeding not just themselves, but another million tiny mouths back at their nests.
15:27And that is precisely where these immense invertebrates are headed to.
15:42You see, life as a giant cricket is tough.
15:50Protein is crucial for these goliaths to sustain their huge frames.
15:59So they must seize any opportunity to eat meat.
16:19It's hard to slip under the radar, though, when you're massive.
16:32So they've evolved some nifty defences.
16:42A spiny, beak-proof armoured shell protects its insides.
16:49And it can fire blood from paws in its exoskeleton.
17:01Temporarily blinding its assailant.
17:04Temporarily blinding its assailant.
17:14With security out of the way, the meat feast is finally within reach.
17:34This big beast has evolved to use its brawn and its weapons to get the meal it needs to stay alive.
17:41The leaf litter is rife with oversized invertebrates, with appetites to match.
18:11The Kinabalu giant red leech would span the whole length of a grown man's thigh.
18:21It maintains its full figure by eating its next-door neighbour.
18:28The Bornean blue earthworm.
18:32It's even bigger than the leech.
18:36Stretching to below a grown man's knee.
18:41In this battle of the titans, though, it's the smallest that wins.
18:53The leech's muscular mouth crushes the worm, taking the phrase down in one to the extreme.
19:00New Zealand's carnivorous poelephanta is the sumo wrestler of the snail world.
19:12The largest can grow to the size of a fist.
19:16And that is just the shell.
19:17Their unfortunate prey is scraped into the gullet by a rasp-like structure, embellished with 6,000 teeth.
19:31Japan's finger-length giant hornet is one of the largest, heaviest and deadliest insects in the world.
19:50It feeds on the larvae of the humble honey bee.
19:57To get to its meal, it must fight its way into the hive.
20:04A team of 30 can decimate a 30,000-strong hive in just three hours.
20:18SAFE
20:25CALE
20:27SAFE
20:31SAFE
20:33CALE
20:44Our big beasts may have got their dining options sorted, but for some, size poses
20:54another challenge, when nature turns up the thermostat.
21:07The red kangaroo is the world's largest marsupial.
21:35It can grow to a towering height of almost two metres.
21:41A single leap can cover seven metres, allowing them to hit a top speed of 35 miles per hour.
21:56But any exercise generates heat.
22:02Big bodies like these have comparatively small surface areas, making it hard for heat to escape.
22:12As the temperature soars, they head for shade.
22:28To cool their overheating bulk, they pace themselves in their own refreshing saliva.
22:38Their forearms are covered in a cobweb of capillaries.
22:42As the saliva evaporates, their blood cools.
22:47The blue parts of this thermal image are the coldest, showing just how effective their
22:52saliva bath can be.
23:06They also dig down beneath the scorching earth, to the cooler soil below, to sit out the worst
23:12of the day's heat.
23:19Sometimes the simplest solutions are the cleverest.
23:38In Australia's Northern Territory, a famously sun-averse mammal is also wrestling with the temperature.
23:49Staying cool just requires escaping the jaws of death.
23:57The little red flying fox is not so little.
24:15It's a species of megabat, with a body as big as a rat and heavier, and a wingspan of
24:27a metre.
24:33If temperatures hit a tipping point of 40 degrees Celsius, hundreds of these big bats can die.
24:47It's 38 degrees, dangerously near the death zone.
24:53300,000 bats are dehydrating.
24:59Their burly bodies are producing more heat than make and release.
25:05What they really need is water.
25:16Skimming the river's surface with their chests is refreshing.
25:21But more importantly, it collects water in the hairs, to lick off back at the roost and quench
25:26their thirst.
25:28But they're not the only ones making the most of the river.
25:44This is the Australian freshwater crocodile, or freshy to the locals.
25:51The sun makes these cold-blooded reptiles alert and ready to hunt.
26:19This deadly game of tag is non-negotiable.
26:24If they don't risk becoming fodder for a freshie, they'll die in the heat.
26:44But the fortune favours these brave bats.
26:49Most of the time.
27:05So being big is not so great when it's hot.
27:11But can a bulky frame help stave off the cold?
27:18Well if you're warm-blooded, the answer is yes.
27:24Mammals tend to be beefier in cooler climes.
27:30Take the biggest bear on earth, the polar bear.
27:36This huge volume stores the heat in temperatures as low as minus 37 degrees Celsius.
27:45And their 10 centimetre blubber layer is such an effective insulator, these mighty mammals
27:50sometimes need a good rub in the snow to cool down.
28:02But if you're cold-blooded, you rely on a daily dose of sun to warm up your insides.
28:10So reptiles and insects generally fare better in the cold when they're small.
28:18Some species, though, just can't help but defy convention.
28:25Remember the gargantuan bird-eating cricket of the Kalahari?
28:29Well, it has a distant cousin that beats it hands down in the size stakes.
28:39This colossal beast is the mountain stone wetter.
28:45An insect that's grown as big as a mouse.
28:49For one simple reason.
28:54Wetters evolved back when there were no native mammals.
28:59So they took the ecological niche normally reserved for small rodents and matched them for size.
29:09Wetters evolved back when there were no native mammals.
29:10Being a massive insect is fine when it's warm.
29:14But this monster species lives high in New Zealand's southern alps.
29:22It had to evolve a way to survive being big in the cold.
29:38By doing something no other insect this large can.
29:47Even in the shelter of a cave, it can be below zero.
29:52When ice sets in around it, this ingenious hulk of an insect does something very strange
29:58indeed.
30:01It freezes itself to death, nearly.
30:15This wetter species actually encourages ice to form in its body.
30:23Ice crystals are sharp.
30:25If they form inside a cell, they'd tear through the membrane like razor blades in a balloon.
30:34So the key to survival is to ensure ice only forms outside its cells.
30:43First, the wetter dehydrates the cells, drawing water out.
30:50There the combination of water and special proteins trigger the formation of ice crystals.
31:07In this state of suspended animation, a mountain stone wetter can survive temperatures as low as
31:14minus 10 degrees Celsius.
31:20An extraordinary 80% of its body can be frozen solid.
31:35When temperatures rise and the ice thaws, a wetter can gradually re-enter the land of the living.
32:03Having got their temperature under control, our big beasts can go about their day.
32:09But the simple act of moving can be challenging in itself.
32:19Generally, the bigger the beast, the more it weighs.
32:25Even the heavier the beast, the harder it finds lifting its weight against the downward pull of gravity.
32:40It's one of the largest earth's largest land animal, the six-ton African elephant.
32:49Tracking down food in the Namibian desert can mean lugging its eye-watering load for 25 miles
32:56a day, two-thirds of an elephant's weight is channelled through its front legs.
33:14The solution?
33:16Fatty pads in its dustbin-sized feet to absorb the shock.
33:25With each step, they spread the load, protecting the skeleton from the impact of its monumental weight.
33:38Even with the help of ingenious evolutionary adaptations, though, the fact remains that gravity limits how big a land animal can get.
33:56So how do big beasts fare beneath the waves?
34:11On here, water's buoyancy helps support nature's heavyweights.
34:22Which is why this is the domain of the most enormous animal ever to have existed.
34:33The 150-ton blue whale outdoes even the biggest dinosaurs for size.
34:44Its tongue alone weighs as much as its largest land rival, the elephant.
34:52Its heart is almost as big as a golf buggy.
34:59Its major artery is as wide as a human head.
35:05And it's thought they're still growing.
35:11As long as the blue whale has enough food, this species may just keep on getting bigger.
35:22Despite its eye-popping stats, the blue whale can move with ease.
35:31Which is more than can be said for excessively heavy beasts that want to get airborne.
35:44Some birds have found benefits to growing big, but in the process, they've lost the ability to fly.
35:56Take the kakapo, the world's heaviest parrot.
36:08To reach the fruit and leaves that maintain its full figure, it has no choice but to climb.
36:22The ostrich has a similar problem.
36:27It's the largest living bird, nearly 3 metres tall, with a vast 2 metre wingspan that is useless for flying.
36:39Instead, it's perfected the art of running away from predators.
36:49With a top speed of over 40 miles per hour, it's the fastest two-legged animal on earth.
36:56It could complete a marathon in 45 minutes.
37:11Being big, though, doesn't have to make air travel impossible.
37:18Over 65 million years ago, a beast far larger and heavier than an ostrich proudly displayed
37:25its aerial skills in the skies above what is now Europe.
37:36Hatsa gottrix may well be the largest flying animal ever known.
37:50If it were alive today, it'd be tall enough to peer into a first-floor window.
37:59And they could take off from a standing start, owing to the sheer power of their wing muscles.
38:11Despite their impressive aerial antics, it seems they didn't hunt on the wing, but fed on the ground.
38:20They're supporting their great weight with extra feet on each wing.
38:40Back in the 21st century, the bird that comes closest to a Hatsi is the albatross.
38:47At 3.5 metres, the wandering albatross has the longest wingspan of any bird alive today.
39:04And an albatross can do something Hatsi apparently couldn't.
39:14Hunt from the air.
39:19These big birds spend most of their lives at sea, scouring the ocean's surface for food.
39:25They only come in to land to breed.
39:44This royal albatross has made a pit stop on New Zealand's South Island, where her two-month-old chick is waiting for food.
39:57This big baby can polish off half a kilo of fish in a single sitting.
40:16To find its next meal, mum will have to scour a mere 600 miles of ocean.
40:29So given she weighs as much as a small dog, how does she manage to fly?
40:35Her enormous wings get her big body airborne.
40:44The secret to the albatross staying up there, though, is in its nostrils.
40:50Special sensory organs measure the speed of the surrounding air.
40:59What they're searching for are changes in airspeed.
41:03At the water's surface, the air is almost still, slowed as it hits the waves.
41:1310 metres up, it's windier.
41:23As an albatross climbs into the faster air, it gets free lift.
41:29Then, turning sharply, it plunges down into the slower air.
41:36Gravity has helped it accelerate to over 70 miles per hour.
41:43Downward momentum catapults it back up again, like a roller coaster, into the lift of the faster air.
42:04It's called dynamic soaring.
42:09And crucially, it means they can fly without flapping their wings.
42:18By exploiting the energy of the wind, they expend almost none of their own.
42:33This aerial efficiency is what makes such a big body capable of flying non-stop for over 10,000 miles without the need to set foot on dry land for years at a time.
42:45For a mother, though, it's straight back to the nest, to satisfy the big appetite of her chunky chick.
43:03The demands of rearing massive offspring is something many a big beast can appreciate.
43:22The challenges often begin at birth.
43:39Because of her size, a hippo keeps cool in water.
43:44It's here that she'll usually deliver her 45-kilo, metre-long baby.
43:54Which leaves her with a problem.
43:59Her little one can't breathe underwater.
44:03Giving mum just 40 seconds to get her newborn to the surface for its first gulp of air.
44:09Elephant babies spend nearly two years in the womb to reach their record-breaking 100-kilo birth weight.
44:32They take so long to grow that mum has to nurse them for up to four years.
44:55For some big beasts, though, the trials of the mating game begin long before the birth.
45:08It's the breeding season on the beaches of northern Patagonia.
45:13Over 15,000 female southern elephant seals have flocked here to find themselves a truly massive mate.
45:34A bull seal can be a staggering eight times his suitor's size.
45:40He can weigh as much as six dairy cows.
45:54And yet she's not the one in danger of getting injured in this game.
45:58He is.
46:01To secure his legacy, a male must mate with as many lucky ladies as possible.
46:10He is.
46:14These females are all under the watchful eye of one bull.
46:23He's the beach master of a harem that can number 150.
46:28To protect his exclusive mating rights, he has to stay on his beach territory 24-7, without food or drink, for three months.
46:42Luckily for him, he's really fat.
46:48His 15-centimetre blubber, born of a diet of just seafood, provides him with energy and water.
46:56For an extra boost, while napping, he holds his breath for minutes at a time.
47:10Every ounce of energy must be saved.
47:12Competitors are always nearby.
47:23Competitors are always nearby.
47:26Let's go.
47:56It's a battle of bulk... and teeth.
48:10His fat suit can't protect him from his rival's eight centimetre canines.
48:26But even after months of fasting, the beachmaster defeats his challenger.
48:42His prize? To father most of the pups this season.
49:00For the loser, it's game over. Three quarters of bulls each year never get to mate.
49:15It's the bigger the better in the elephant seal mating game.
49:19Securing the next generation is a risky business. Not just for males.
49:25One beast has grown so big that having babies means gambling with her life.
49:35Securing the next generation is a risky business. Not just for males.
49:40One beast has grown so big that having babies means gambling with her life.
49:55One beast is a humble hermit crab. Harmless and traditionally small.
50:04Except for this member of the family.
50:10The coconut crab. Or robber crab. The largest land crab on earth.
50:21The South Pacific islands of Vanuatu are pretty hard to reach.
50:25So having the place mostly to themselves, it seems these critters have taken the opportunity to grow as big as medium sized mammals.
50:40Their legs can span a metre.
50:43And they're strong enough to lift the equivalent of ten house bricks.
50:51Being big has allowed them to cultivate some rare talents.
51:01True to their name, they can crack a coconut.
51:08And they've been known to kill and eat rats.
51:10But there's one thing these crabs simply can't do.
51:17And that is swim.
51:26This crab lives its adult life entirely on land.
51:30So you'd think this wouldn't be too much of a problem.
51:33And for most of their days, it isn't.
51:40But once a year, the females of these colossal crustaceans have no choice but to brave the waves in order to pass on their genes.
51:52This female has been nursing her fertilised eggs on her abdomen, having mated some weeks ago.
52:04But tonight's the night to release her precious cargo.
52:05This female has been nursing her fertilised eggs on her abdomen, having mated some weeks ago.
52:17But tonight's the night to release her precious cargo.
52:21And like all crabs, that's done in water.
52:35She must tread carefully.
52:36She's so well adapted to land, that she's evolved a form of lung that can no longer breathe underwater.
52:49And her great weight means if she gets out of her depth, she'll sink and drown.
53:02Clinging for life, she releases her eggs into the waves.
53:17They'll hatch into swimming larvae.
53:20But in a month's time, they'll be back on land.
53:32There they too will grow into terrestrial giants.
53:35Across the coral sea from the coconut crab's paradise isle is an immense sea beast that also reproduces just once a year.
54:01When it does, it gets even bigger.
54:12This springtime full moon is the trigger for a submarine spectacular.
54:20When the perfect tide height, day length and sea temperature all align, this happens.
54:31400 species of coral across 3,000 reefs reproduce over a series of nights.
54:51Tucked inside their limestone armour, millions of coral polyps release their eggs and sperm simultaneously.
54:59Tucked inside their eggs.
55:06You may be wondering what's big about these tiny floating jewels.
55:10Well together, they're responsible for growing the world's largest single living structure.
55:18The Great Barrier Reef.
55:30At 1400 miles long, it's over twice the length of Great Britain.
55:36Making it the only living thing visible from space.
55:40Each time the reef reproduces, its gigantic scale increases.
55:46The resulting coral larvae travel back down to make their home on the reef.
56:00This monumental structure once grew by several centimetres each year.
56:13Of course, there's a twist to this tale.
56:24In recent years, it's thought that half the coral in this big beast has died.
56:30It's believed rising sea temperatures are responsible for driving away the colourful algae that live inside coral.
56:43Without nutrients and its distinctive hues, it's left bleached white.
56:50It appears our modern world is taking its toll on this great beast.
57:00We may not be amongst nature's biggest beasts, but we do so often have the biggest impact on our planet and on the animals we share it with.
57:18Our fascination with the Goliaths of our world can prove catastrophic for them.
57:31And nature's giants can't survive without ample space to roam, plenty to eat and prime habitat.
57:39Half the remarkable titans featured here are threatened with extinction.
57:59When you consider the astonishing solutions nature's biggest beasts have come up with to life's big problems.
58:09Ingenious ways to find food, to keep warm or stay cool, to move around and to reproduce.
58:23We should not only celebrate their success, but also do what we can to ensure they stick around for generations to come.
58:39We're grateful for the last couple of years.
58:42Let's talk about the glory.
58:43We'll see you next time.
58:45We'll see you next time.
58:48Bye.
59:09You
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