- 2 days ago
地球一日
Category
🐳
AnimalsTranscript
00:03The Sun.
00:12It creates the daily rhythm for life on Earth.
00:23A player in almost every drama that unfolds across our planet.
00:32Hour by hour, its exact position is critical.
00:52For some, it brings moments of enormous opportunity.
00:56For others, it can spell disaster.
01:04All over the world, animals' lives are governed by the Sun's journey through the sky.
01:13How they respond can make the difference between success and failure, life or death.
01:23This is just an ordinary day on our extraordinary planet.
01:43It's dawn.
01:58The Sun hasn't arrived yet, but its power will soon be felt.
02:04And the world is waking.
02:14The day starts with a love song.
02:36Lar Gibbons.
02:44With each note, they renew their bond after the long night.
02:50And remind other gibbons that this patch of forest is theirs.
02:58They've discovered that the hour before sunrise is the perfect time for their duet.
03:14Because sound travels furthest in cool air.
03:22And at dawn, a warm layer sits above the cool air.
03:27Reflecting and amplifying every note.
03:33It's the best time of the day to be heard.
03:36And the gibbons aren't the only ones making the most of it.
03:58All over the planet, nature's dawn chorus heralds the moment the world's been waiting for.
04:20thyHH
04:24Nodi
04:26Asher
04:26By eve
04:32By eve
04:50Our star, a burning giant, reappears above the horizon.
05:04Its rays, travelling at over 180,000 miles per second, flick the switch and the world is flooded with light.
05:44This meerkat family is up early to greet the sunrise.
05:52It's not high enough to warm them up just yet.
05:57And they're finding it difficult to get going.
06:07But unbeknown to them, the early light is having an extraordinary effect inside their bodies.
06:27Sunlight triggers the brain to shut off drowsy hormones, replacing them with waves of energizing ones, kick-starting their metabolism
06:36and preparing them for the day ahead.
06:43Suddenly, they're wide awake.
06:48Time to find breakfast.
06:56All over the world, the rising sun is making its presence felt, forcing animals into action.
07:10For the last eight months, South Africa's rocky shoreline has been a nursery for this young Cape fur seal.
07:24He too is hungry, but the need to fuel his body is about to get him into trouble.
07:37Each morning with the rising sun, the current moving past the mouth of the bay brings rich pickings.
07:51But with opportunity comes danger.
08:04A killer patrols these waters.
08:11Waiting for inexperienced pups to take the plunge.
08:17The older seals know the great whites are out there.
08:20But by midday, the biggest fish shoals will be out of range.
08:26The seals must leave.
08:29Now.
08:30Now.
08:31Now.
08:37The pups' best chance is to fall in with a convoy of adults.
08:44Experienced seals are notoriously hard to catch.
08:50But in the first two hours of the day, the great white has a better chance.
08:55Thanks to an ally.
08:59The sun itself.
09:03The early morning light is strong enough to silhouette the pup from below.
09:13But the slanting rays can't penetrate the depths.
09:19The shark can see the pup, but the pup can't see the shark.
09:25The shark comes in from below.
09:25I don't know.
09:55I don't know.
10:03This time the pup is just small and speedy enough to slip through the shark's jaws.
10:12Away from the coastline, he's safe.
10:21And as the sun rises higher, illuminating the shadowy depths, the shark's window of opportunity closes.
10:35At least until tomorrow.
10:42As the sun climbs higher in the sky, its character is changing.
10:50For the first time in the day, it's not just sensed as light, but as radiant heat.
11:10Clusters of monarch butterflies huddle close together against the chilly Mexican night.
11:21Up until now, the morning has been too cold to leave the branches.
11:27But as the sun hits their wings, warming their bodies to a crucial 12 degrees, they can finally fly.
11:46Each cluster revealing tens of thousands of individual butterflies.
12:01The first warmth of the day is just as important to small mammals.
12:10These Madagascan lemurs aren't meditating.
12:15They're sunbathing.
12:24Too small to regulate their body temperature well.
12:29They lie back and soak up the warmth through their thinly coated underbellies.
12:35A much needed morning heat fix.
12:42But nowhere is the warming of the landscape felt more keenly than in the desert of Namibia.
13:00Overnight, the temperature hit freezing point.
13:03But this morning, the sun is radiating heat directly onto the sand dunes.
13:10Three hours after sunrise, and already the temperature has climbed by 30 degrees.
13:18Exactly what this desert inhabitant has been waiting for.
13:29The Namaqua is unusual, which for a chameleon is really saying something.
13:40Somewhere in its evolution, it drew the short straw.
13:50So whilst its cousins around the world live hidden in trees, the Namaqua is exposed on sand-blasted dunes.
14:02Just surviving the freezing night has left the cold-blooded chameleon sluggish.
14:10Its energy supply is so drained that breakfast passes right under its nose.
14:18It's going to need to get warm before it can eat.
14:41By angling its dark brown, scaly skin towards the light, it becomes a reptilian solar panel.
14:47By angling its dark brown, scaly skin towards the light, it becomes a reptilian solar panel.
14:57An hour or two on charge, and it will be good to go.
15:09In less extreme parts of Africa, this change in air temperature has burnt the hanging morning haze away.
15:18In just a couple of hours, the ground will become so hot that it will begin to generate a heat
15:24haze of its own.
15:26But right now, in this brief window of clarity, with nothing to spoil her view, conditions for this cheetah are
15:35perfect.
15:40She's a mother, with responsibilities, three of them.
15:48They're growing fast, and they're hungry.
15:54Mum needs to make a kill.
16:11The lions who share her territory have excellent night vision.
16:16But the cheetah's eye is designed for sunlight.
16:21Packed full of colour receptors, she sees the world in razor-sharp detail.
16:28The lions could threaten her cubs, but they're stuffed full from the night's hunt.
16:37Right now is her best chance.
16:50Black tear stains under her eyes combat glare and help her focus in the crisp morning air.
17:06Watches these caricatures move them all together.
17:12Water.
17:32How it is, it's rational it's not the evil for us.
17:42Just in time, the heat haze will soon be shimmering above the ground, making it difficult
17:50to see in any detail.
17:53Then the time for hunting will be over.
17:58And the best option? To spend the rest of the day in the shade.
18:14In more temperate parts of the world, plants have been working hard since dawn.
18:25Photosynthesizing light into energy.
18:30In the next hour, the sun's intensity will peak.
18:40These light harvesters are gearing up for what should be the most productive moment of
18:45the day.
18:47But it's also when the sun becomes its most dangerous.
18:56As damaging to plant cells as it is to our skin.
19:01As the sun blasts down from overhead.
19:09These sunflowers are carefully monitoring its intensity.
19:15Flooding each leaf with a sunscreen.
19:18Protecting the plant from sun damage.
19:23At 90 degrees, directly overhead.
19:28The sun's rays pass through the least atmosphere.
19:31as it is Lululd's new one.
19:31The sun sl gladiants have!
19:33If you have done it.
19:34They look후 at all the clouds.
19:58Their sun, their perception of water, valt João, etc., etc., etc.
20:19to the earth in the australian outback temperatures have soared past 50 degrees
20:28out in the open these kangaroos are becoming dangerously hot
20:41the shade gives some relief but it's not enough the air surrounding them is baking
20:54to prevent heat stroke these roos have a trick or two up their sleeves
21:03along their forearms vessels full of hot blood run close to the skin
21:13they lick themselves
21:25as their saliva evaporates a little body heat is lost with it
21:33and by digging away the hottest layers of earth and resting on the cooler layers below
21:45these resourceful roos have found a way to survive the midday onslaught
22:01shade is hard to come by in the namibian sand dunes
22:12our cold-blooded chameleon is in danger of being cooked in his own skin
22:34but life in this uncompromising place has forced an incredible adaptation
22:51doing what chameleons all over the world do best it's changed color dark brown to brilliant white
23:05reflecting the heat off its skin and keeping its internal temperature just cool enough to survive
23:15and to hunt
23:25a solar-powered turbocharged chameleon
23:35well relatively speaking
23:53not everyone finds the midday sun such a challenge
24:00in a lake on a remote island in the pacific
24:05a golden jellyfish is sunday
24:17this is no ordinary jelly
24:24over 12,000 years ago its ancestors were marooned here
24:33faced with starvation this seafarer became a farmer
24:41absorbing lake algae into its body and cultivating
24:48the algae use light to photosynthesize sharing the energy generated with their hosts
24:58the jellies carefully tend the algae following the path of the sun across the lake
25:07it's such a successful relationship that now there are 13 million jellies
25:25all clustered under the midday sun
25:29gently spinning to give their crop just the right amount of light
25:45from midday onwards the angle of the sun begins to wane
25:51but it becomes no less dangerous
25:57the ground temperature carries on rising
26:07while most animals wait for the earth to cool
26:13amongst the craggy peaks of the ethiopian mountains
26:18a quirky looking crowd is gathering
26:23lamagaias are vultures scavengers
26:30collectors of bones
26:34partial to the marrow found inside them
26:39heavy duty stomach acid dissolves small bones
26:42but they're not exactly nutritious
26:49a lamb femur full of marrow is much more like it
26:55but there's a problem
26:56the bones far too big to swallow
27:03in the warmth of the afternoon
27:06this lamagaias senses an opportunity
27:14heat radiating from the plains below has built into huge columns rising into the atmosphere
27:26warm air thermals perfect for flight
27:44the lamb bone matches her own body weight
27:47but the early afternoon thermals create an invisible elevator
27:51making flight possible
27:53the
27:55the
27:58the
27:59the
27:59the
27:59the
28:00the
28:03the
28:04the
28:05the
28:05the
28:07the
28:07the
28:08the
28:09the
28:14the
28:17at any other time this maneuver would prove dangerous and costly energy
28:27but by seizing her chance she's been rewarded
28:39it. Delicious.
28:57While the Lama Gaia rides early afternoon thermals close to the equator, a polar bear right
29:05at the top of the Earth is facing a very different challenge.
29:15Because of the tilt of the Earth on its axis, the Arctic summer is filled with almost endless
29:20light.
29:37Hunting seals under the sea ice, he's in no rush.
29:45At three o'clock in the afternoon, the sun is still high in the sky.
29:52But the radiant heat from days of endless summer is melting his arctic world.
29:59The Earth is still high in the sky.
30:04The Earth is still high.
30:24Oh, my God.
30:56Oh, my God.
31:24The sun will stay high over the Arctic for another two months.
31:29Soon, there'll be no ice left to hunt on.
31:32He will have to fast until the seasons change again.
31:40It's this seasonal journey of the sun in the sky that causes the greatest movement of animals across the planet.
31:46The sun will die.
32:21Driven by changes in weather, by opportunity and danger, migrants crisscross the planet, across continents and through oceans.
32:43Even the lives of the greatest travellers are ruled by the sun.
32:54This family of humpback whales spent the winter breeding in tropical waters, which made the perfect nursery for the new
33:04calf.
33:07But are low on stocks of krill and small fish, the things 30-ton adults like to eat.
33:19The calf is now strong enough to swim the 3,000 miles north, towards the family's next big meal.
33:56of miles of featureless ocean is an incredible challenge.
34:00And with the adults running on empty, they can't afford to get lost.
34:06But the sun throws them a lifeline.
34:13Humpbacks are expert navigators.
34:26They use the sun to keep their bearings.
34:33Its changing position in the sky,
34:35combined with information sensed from the Earth's magnetic field,
34:39creates a reliable compass.
34:50So effective is their reckoning
34:52that between sunrise and this point in the afternoon,
34:57the family will have deviated less than one degree from last year's course.
35:12Late afternoon.
35:16The sun's time in the sky is running out.
35:19Its power is fading.
35:27Animals face an urgent new challenge.
35:30To make the most of the remaining light and warmth before it disappears.
35:41Back in Namibia, the sand is beginning to cool.
35:47the sun's time in the sky.
35:48And the chameleon has undergone his most bizarre transformation yet.
35:59He split himself right down the middle.
36:12Black's side face towards the sun to absorb every last bit of remaining warmth.
36:22White in the shade to stop his body heat being lost.
36:32Being two chameleons at once will help him survive the cold night ahead.
36:43And he's not the only animal torn between the heat of the day and a chilly desert night.
36:57In the mountains of Oman,
36:59a rock hyrax family are soaking up all the late afternoon heat they can get.
37:08They could also be accused of having a bit of an identity problem.
37:20They could also be accused of having a bit of an identity problem.
37:32And although they're mammals, they need to bask to keep warm, just like lizards.
37:42Sunbathing in the late afternoon is a serious business.
37:49Every extra minute spent absorbing warmth from the rocks gives them a better chance of surviving the cold night ahead.
37:59But stretching out in the open like this is dangerous.
38:04They've no choice but to make themselves targets.
38:10And stone-baked hyrax is a black eagle favourite.
38:18The family are on high alert.
38:26The eagle's only chance is a stealth attack.
38:32And the afternoon sun provides the perfect disguise.
38:37Diving at the same angle.
38:41The glare is an invisibility cloak.
38:45But hyrax have a unique adaptation.
38:49In their eye, the coloured iris slightly shields the top of the pupil.
38:57An in-built sun visor.
38:59Perfect for eagle spotting.
39:12There won't be hyrax on the menu tonight.
39:25There's less than two hours left before sunset.
39:29The sun has lost its strength.
39:32But it has not lost its grip on our planet.
39:36It has one last hand to play.
39:46The phenomenal energy absorbed by the ground during the hottest parts of the day is released back into the atmosphere.
39:56Fast rising unstable hot air colliding with higher colder air creates weather.
40:04Weather.
40:33Guitar
40:34equator rain in the afternoon is just something you've got to put up with
41:07a waterproof makes it all much more bearable although this young orangutan hasn't quite
41:16got the hang of making his just yet but over drier parts of our planet
41:34all this pent-up heat energy can spell disaster
41:44turbulent air creates static charges
41:52lightning each strike five times hotter than the surface of the Sun
42:10parched forests take like tinder to a match
42:26the fire will eventually burn itself out but the smoke lingers scattering all but the very longest
42:35wavelengths of light reds and oranges while the earth smolders the Sun set burns extra deep
42:52it takes on average just two minutes for the Sun to sink below the horizon
42:59such a short time in which everything changes for life on earth
43:15the Sun's great energy its light and heat is suddenly lost
43:28all over our planet families regroup and find the safety of their beds
43:37as drowsy hormones flood back into their bodies pulling them into sleep
43:49but not everyone's quite ready to let the day go above a limestone cave in Borneo a hawk a day
43:59flyer
43:59has not yet flown to its roost what it's waiting for is just beginning to stir
44:20inside the cave a storm is brewing
44:35the beating wings of millions of wrinkle-lipped bats
44:49they use sound more than sight to navigate
44:52so leaving the cave before dark won't help them find food
44:58but there's just so many of them that flying any later would cut into valuable feeding time
45:24by pushing out into this last brief window of light they're taking a huge risk
45:33the hawk is just one of many that's ready for them
45:42the hawk is just one of many that's ready for them
46:14it's a twilight battle of the senses
46:17sonar versus eyesight
46:26in the last moments before complete blackness eyesight still wins
46:32and their lives
47:02and again
47:12As the very last of the sun's rays are lost behind the horizon,
47:18for the first time, the planet is in true darkness.
47:25The night-time world.
47:38The darkness holds a lure for a whole host of permanent night dwellers.
47:57They've acquired very different senses that don't rely on sunlight.
48:10This scorpion has spent the daylight hours hiding deep in crevices to avoid being eaten.
48:21But when the sun's quite absent, she becomes the predator.
48:39Her small eyes are all but useless in the darkness.
48:44Instead, she senses prey through vibrations.
48:53The movement of a single grain of sand gives her all the information she needs to attack.
49:12But just as she closes in on her first meal of the night, she freezes, sensing danger.
49:26Even in the dead of night, our sun is still not lost.
49:35Its rays pass by the dark side of the earth and reflect off its moon.
49:56A ghost sun.
50:06The full moon rises high and bright.
50:14And the scorpion begins to glow.
50:32Ultraviolet light reacts with fluorescent chemicals in the scorpion's armour.
50:41Her eyes can't see moonlight.
50:44But her whole body is a warning system, telling her that her cover is blurred.
50:51She needs to hide before a predator sees her.
50:55So she uses the fluorescence to her advantage.
50:57So she uses the fluorescence to her advantage.
51:01As a light sensor.
51:05As a light sensor.
51:09Any part of the...
51:17telling her she's found safety.
51:29Telling her she's found safety.
51:32the moon.
51:36Known as Lunophobia.
51:39Many nocturnal species around the world will hide away.
51:47And choose to go hungry.
51:50Rather than risk coming out under the reflected sunlight.
52:01But to a hunter in Southeast Asia, a bright lit night is an opportunity to be seized.
52:19Every night, the rainforest's insect population comes under attack.
52:23From a palm-sized primate.
52:34Don't let the wide eyes fool you.
52:36This family of spectral tarsiers are ruthless hunters.
52:51With saucer-like eyes, each as big as their brain.
52:55This family use the faintest of starlight to see the forest in incredible detail.
53:17And when your eyes are this sensitive, all this reflected sunlight is a gift.
53:38The family aren't about to miss a moment of the best hunting night of the month.
53:52In the moonlit forest, the family might triple their hunting success.
54:03But it's all too easy for a tarsier to have eyes bigger than its stomach.
54:12In the early hours, full to bursting, the family call it a night.
54:28It's nearly morning.
54:30The moon is hanging just above the horizon.
54:34Soon it will be overwhelmed by the first light of dawn.
54:45But in the Arctic, the sun is casting a new and different power over the last few hours of darkness.
54:58Particles thrown from the sun's surface cross 90 million miles of empty space to reach the earth.
55:09They are directed by the earth's magnetic field to the poles.
55:16This cosmic storm creates a magical aurora.
55:23The spectacular northern lights.
55:32But behind this beautiful light show is a sinister force.
55:47That impacts on whales with potentially lethal consequences.
55:57The humpbacks have been relying on the earth's magnetic field to chart their nighttime course.
56:16But the earth's magnetism is becoming distorted under this barrage of solar energy.
56:31It's believed whales can become disorientated.
56:40Thrown off course.
56:44They might even strand onto the land.
56:51But soon it will be morning.
56:54And the sun compass will bring them back on track.
56:57Fallback
56:57umm
57:26partir
57:27The very first light of a new day.
57:36The sun's power will soon be felt.
57:42And the world is waking.
57:47Ready to begin another ordinary day.
57:51On our extraordinary planet.
58:01Nothing can prepare each other.
Comments