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(CHIRRUPING AND ANIMAL CALLS)
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(SQUAWKING AND CHIRPING)
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DAVID ATTENBOROUGH: The natural world
is filled with sound.
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(THUNDERCLAP)
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(CLUCKING)
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(BELLOWS AND SCREECHES)
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(ROARS HOARSELY)
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But so far,
we've been hearing only part of it.
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(CHIRRUPS AND CLICKS)
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(PULSATING SQUEAKS)
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The most advanced audio technology
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can now record sounds
that we can't even hear.
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(DEEP VIBRATING HUM)
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(RATTLING)
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(WHOOPING CALL)
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(SOFT CLICKING)
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(CHIRPS)
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For some animals,
sound is the key to survival.
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(BUZZING)
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(CLICKS AND SQUEAKS)
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They use sound to hunt...
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(FRANTIC SCREECHING)
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(DEEP GROWLING)
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...and escape.
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(PADDING AND RUSTLING)
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(SOFT THUDDING)
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Sound can make the difference
between life and death.
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(SCUFFING)
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(SCUFFING AND PATTERING)
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(HISSES)
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It's time to open your ears
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to life
as you've never heard it before.
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(GRUMBLING AND TRUMPETING)
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(CHIRRUPING AND TWITTERING)
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(SQUAWKING AND SCREECHING)
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(DEEP RUMBLING GROWL)
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(CHIRRUPING)
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(SQUAWKING AND SCREECHING)
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(GRUNTING)
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(CHITTERING AND CROAKING)
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(CACOPHONY OF ANIMAL CALLS)
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(SOFT MOANING)
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(CHIRPS)
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Dawn on the African savanna.
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(GRUNTING)
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(BELLOWING)
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(GRUNTING AND BELLOWING)
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It's the best time of the day
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for lions to broadcast their message.
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(GRUNTS)
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(BELLOWS HOARSELY)
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(BELLOWS HOARSELY)
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(BELLOWING CONTINUES)
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As the sun rises,
cold air is trapped near the ground.
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Because it's denser than warm air,
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it allows sound to travel further
before dissipating.
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(GRUNTING ECHOES)
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(GRUNTS)
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It's a declaration to other prides
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of his ownership
of these hunting grounds...
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...and the key to his
and his pride's survival.
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(RUMBLING GROWL)
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(BELLOWS)
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It's one of the greatest
acoustic displays of power in nature.
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(HIGH-PITCHED BELLOW)
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(DEEP RUMBLING ROAR)
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(GRUNTS AND ROARS)
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(GRUNTS AND ROARS)
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(GRUNTS)
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He can be heard
up to five miles away.
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(RUMBLING ROAR)
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(DEEP GRUNTING)
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But even this isn't far enough
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to reach the boundaries
of their territory.
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It spans over 150 square miles.
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To defend an area
as immense as this,
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the pride must roam and roar.
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(SONOROUS RUMBLING ROAR)
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But some members are too small
to get very far.
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(YOWLS)
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This pride is protected
by three brothers.
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Together, they head off on patrol.
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A lion's roar sends a clear message
to other prides.
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But sound can also be used
in more subtle ways.
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(CHIRRUPING)
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(TWITTERING AND CHIRPING)
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(LOW BUZZING)
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(BUZZING CONTINUES)
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(BUZZING AND HUMMING)
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(INTENSE BUZZING)
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This garden is filled with the sound
of the buzzing of bees.
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It's a sign that the plants have been
successful in attracting pollinators
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with their brightly-coloured flowers
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and seductive smells.
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(INTENSE BUZZING)
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The buzzing sound
we associate with bees
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is a by-product created by
the beating wings as they fly.
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(BUZZING)
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(BUZZING)
100
00:05:40,360 --> 00:05:43,960
But some bees
take advantage of their buzz,
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and use it,
in a surprisingly sophisticated way,
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to get to a supply of food
that others can't reach.
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(BUZZING)
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One such bee lives underground.
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(BUZZING THRUM)
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These are buff-tailed bumblebees.
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For the colony to survive,
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each worker must collect
as much pollen as she can
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with which to feed their young.
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(CONTINUOUS BUZZING THRUM)
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Searching for it
is a constant preoccupation.
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(SOFT RUSTLING)
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(INTREPID MUSIC)
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(BUZZING)
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It's spring in England...
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(BUZZING)
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(SOFT FLUTTERING)
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(FLUTTERING AND CLICKING)
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(GENTLE BUZZING)
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...and she is not the only one
in search of food.
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Competition for pollen and nectar
is high.
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And poppies are putting on a show.
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Packed full of pollen,
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they flaunt it at the top
of long filaments called anthers.
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(BUZZING)
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These flowers are a free-for-all...
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...and everyone
is seeking a share of the bounty.
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(BUZZING)
129
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(HARMONIOUS BUZZING)
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But she doesn't need to compete
with other species
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if she can find
a particular kind of flower.
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(SOFT FLUTTERING)
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She's found
what she's been looking for...
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(SOFT BUZZING AND FLUTTERING)
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...a type of nightshade.
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(BUZZING)
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Its flowers are less striking
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and, unlike poppies,
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its pollen is locked up
inside long yellow anthers.
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The only way for it to escape
is through tiny holes.
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The bumblebee holds the key
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that unlocks this treasury of pollen.
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Sound.
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Locking in her wings,
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she uses her flight muscles
to vibrate her whole body,
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buzzing up to 370 times a second.
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(INTENSE BUZZING)
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This sonic assault
blasts the pollen loose.
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(BUZZING CONTINUES)
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She then grooms the pollen
down into sticky sacs on her legs
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and flies off to the next flower.
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(INTENSE BUZZING)
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Very few species
can buzz-pollinate in this way,
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so bumblebees have nearly exclusive
access to the nightshades' pollen.
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(INTENSE BUZZING)
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The bee's pollination buzz
is higher pitched
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than that made during flight.
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It's the same frequency
as the musical note D.
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(HIGH-PITCHED BUZZING)
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She's like a living tuning fork.
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00:10:18,240 --> 00:10:21,720
Some buzz pollinators
can vary their pitch,
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fine-tuning it
to suit different flowers.
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So pollen is released
in the most efficient way.
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Fully loaded,
she returns to the hive.
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She has successfully used sound
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to help secure the pollen
her colony needs.
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(CONTINUOUS HUMMING)
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We tend to take bees for granted...
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but it's not just plants
that depend on them, we do too.
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00:11:05,200 --> 00:11:08,240
Many of our crops rely on pollinators
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00:11:08,240 --> 00:11:10,720
like bees and other insects.
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00:11:12,120 --> 00:11:15,360
Worryingly, bee populations,
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together with those
of many other insect pollinators,
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are in serious decline
around the world.
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00:11:23,520 --> 00:11:25,360
And with their numbers plummeting,
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00:11:25,360 --> 00:11:29,920
both the natural world and our own
food supplies are in danger.
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00:11:29,920 --> 00:11:31,640
(CONTINUOUS BUZZING)
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00:11:31,640 --> 00:11:34,240
Bees need our help
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00:11:34,240 --> 00:11:37,320
and without them
and the sound of their buzz,
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00:11:37,320 --> 00:11:40,400
the future for us all
would look bleak.
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(INTENSE BUZZING)
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Sound provides the key
to this partnership
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between bumble bees and plants.
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But not all relationships in nature
are as harmonious.
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(BIRDSONG)
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00:12:01,360 --> 00:12:03,400
(DISTANT BIRD CALLS)
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The Bahama Islands in the Caribbean.
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The sand flats here are the home
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of garden eels and razorfish.
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(WATER BURBLES GENTLY)
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(FAINT SQUEAKING)
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But there is trouble in paradise.
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(ECHOEY CLICKING AND SQUEAKING)
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The sound of approaching danger.
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00:12:38,600 --> 00:12:42,560
(ECHOEY RHYTHMIC SQUEAKING)
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It's a cue to hide.
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00:12:44,600 --> 00:12:47,160
(ECHOEY WHISTLING AND SQUEAKING)
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00:12:52,280 --> 00:12:54,440
(SQUEAKING AND CLICKING)
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00:12:54,440 --> 00:12:58,640
A mixed groups
of spotted and bottlenose dolphins.
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00:12:58,640 --> 00:13:00,880
(SQUEAKING AND WHISTLING)
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Their whistles and squeaks are part
of their continuous conversations...
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(CLICKING)
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...with a range of frequencies
seven times greater than ours.
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00:13:13,520 --> 00:13:15,560
(HIGH-PITCHED SQUEAKING)
205
00:13:16,720 --> 00:13:18,720
(CLICKING AND SQUEAKING)
206
00:13:25,760 --> 00:13:28,400
To hunt for food, they must split up.
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00:13:28,400 --> 00:13:30,960
(CLICKING AND WHISTLING)
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Each dolphin
needs 15 kilograms of fish a day.
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00:13:36,600 --> 00:13:39,080
(CHIRRUPING)
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00:13:39,080 --> 00:13:41,400
But, thanks to their rowdy arrival,
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00:13:42,360 --> 00:13:44,360
there isn't a morsel in sight.
212
00:13:47,080 --> 00:13:49,080
The hunt is on.
213
00:13:51,240 --> 00:13:54,200
(LOW GRUMBLING)
214
00:13:56,245 --> 00:13:58,240
(LOW GRUMBLING)
215
00:13:59,240 --> 00:14:01,640
(CLICKING AND CHIRRUPING)
216
00:14:01,640 --> 00:14:04,880
The bottlenose dolphins
now switch from whistles
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00:14:04,880 --> 00:14:07,240
to bursts of fast clicks,
218
00:14:07,240 --> 00:14:09,440
up to 200 per second.
219
00:14:09,440 --> 00:14:11,480
(RAPID CLICKING)
220
00:14:14,240 --> 00:14:16,280
(INTENSE HIGH-FREQUENCY CLICKING)
221
00:14:18,600 --> 00:14:22,880
These high-frequency clicks
are sent out like a sonar beam
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00:14:22,880 --> 00:14:25,880
through an organ in the forehead
called a melon,
223
00:14:25,880 --> 00:14:28,720
with which
they can scan the ocean floor.
224
00:14:28,720 --> 00:14:30,760
(RAPID CLICKING)
225
00:14:38,520 --> 00:14:42,400
When the beam of sound
hits a fish hiding beneath the sand,
226
00:14:42,400 --> 00:14:46,400
it's reflected back,
revealing its location.
227
00:14:46,400 --> 00:14:47,920
(CLICKING)
228
00:14:47,920 --> 00:14:49,560
Using echolocation,
229
00:14:49,560 --> 00:14:52,640
the dolphins are able
to create a visual map
230
00:14:52,640 --> 00:14:54,880
of what is hidden
under the sea floor.
231
00:14:54,880 --> 00:14:57,560
(RAPID CLICKING)
232
00:15:06,360 --> 00:15:09,280
Some of these clicks
are ten times higher
233
00:15:09,280 --> 00:15:12,160
than the sounds our ears can detect.
234
00:15:12,160 --> 00:15:14,400
(HIGH-PITCHED CLICKING)
235
00:15:14,400 --> 00:15:15,760
(SILENCE)
236
00:15:15,760 --> 00:15:19,840
High-frequency sounds
are most effective at close range,
237
00:15:19,840 --> 00:15:24,240
enabling the dolphins to pinpoint
their prey with great precision.
238
00:15:31,920 --> 00:15:36,720
But there is more to these
pirouettes than meets the eye.
239
00:15:36,720 --> 00:15:38,840
(CLICKING)
240
00:15:38,840 --> 00:15:43,560
Scientists have recently discovered
that bottlenose dolphins
241
00:15:43,560 --> 00:15:46,880
favour their
right side when scanning the seabed.
242
00:15:49,360 --> 00:15:54,040
The right side of the head
usually produces the sonar clicks.
243
00:15:54,040 --> 00:15:58,360
And the right side is also better
at detecting the returning echo.
244
00:15:58,360 --> 00:16:00,400
(CLICKING)
245
00:16:01,480 --> 00:16:03,480
(MELLIFLUOUS MUSIC)
246
00:16:11,920 --> 00:16:15,840
The only evidence that there has been
a sonar search here
247
00:16:15,840 --> 00:16:18,720
are small craters in the sand.
248
00:16:33,080 --> 00:16:36,000
Dolphins use sound with great effect
249
00:16:36,000 --> 00:16:38,040
to find their food.
250
00:16:38,880 --> 00:16:41,960
But in other places,
a quieter approach
251
00:16:41,960 --> 00:16:44,240
is the key to a successful hunt.
252
00:16:45,800 --> 00:16:47,800
(DISTANT SQUAWKING)
253
00:16:48,800 --> 00:16:50,840
(DISTANT CHIRRUPING)
254
00:16:50,840 --> 00:16:52,640
(SQUAWKING)
255
00:16:52,640 --> 00:16:54,680
(SOFT RUSTLING)
256
00:16:55,320 --> 00:16:58,160
In the forests of Manitoba
in Canada,
257
00:16:58,160 --> 00:17:02,560
the great grey owl
is a master of silence.
258
00:17:11,480 --> 00:17:13,840
Specially-adapted flight feathers
259
00:17:13,840 --> 00:17:16,280
allow him to approach silently.
260
00:17:17,000 --> 00:17:19,000
(WIND GUSTS GENTLY)
261
00:17:28,320 --> 00:17:31,920
His prey is hidden
under a blanket of snow.
262
00:17:38,640 --> 00:17:40,640
(SOFT SNUFFLING)
263
00:17:43,000 --> 00:17:44,920
Voles.
264
00:17:47,480 --> 00:17:51,080
Finding them in this vast,
snow-covered landscape
265
00:17:51,080 --> 00:17:53,480
seems an impossible task.
266
00:17:57,040 --> 00:17:59,960
To combat the extreme cold,
267
00:17:59,960 --> 00:18:02,680
he must catch seven voles a day.
268
00:18:04,440 --> 00:18:07,320
His ears will be
his most effective weapon.
269
00:18:09,920 --> 00:18:11,680
(SNUFFLES AND SQUEAKS)
270
00:18:13,240 --> 00:18:16,080
Voles need to feed continuously
271
00:18:16,080 --> 00:18:18,040
or they will freeze to death.
272
00:18:18,840 --> 00:18:20,840
(HIGH-PITCHED SQUEAKING)
273
00:18:21,640 --> 00:18:23,840
(PATTERING FOOTSTEPS)
274
00:18:23,840 --> 00:18:28,040
They constantly dig tunnels
to find new food supplies...
275
00:18:29,800 --> 00:18:32,120
...unaware of the danger above.
276
00:18:32,120 --> 00:18:34,160
(SNUFFLING AND SCUFFLING)
277
00:18:37,200 --> 00:18:40,400
Hidden under a face
covered by feathers,
278
00:18:40,400 --> 00:18:42,880
the owl's ears are positioned
279
00:18:42,880 --> 00:18:46,720
at slightly different levels
on either side of his head.
280
00:18:49,040 --> 00:18:51,640
Sound will hit one ear
before the other,
281
00:18:51,640 --> 00:18:55,600
allowing him to pinpoint his prey
with great accuracy.
282
00:19:01,640 --> 00:19:04,360
His acoustic arsenal
doesn't stop there.
283
00:19:07,680 --> 00:19:10,040
The large facial ruff,
284
00:19:10,040 --> 00:19:13,440
formed from feathers that are
particularly stiff and dense,
285
00:19:13,440 --> 00:19:17,480
help to amplify sound
and funnel it towards the ears.
286
00:19:26,440 --> 00:19:28,440
(RUSTLING AND SQUEAKING)
287
00:19:30,800 --> 00:19:33,280
Through half a metre of snow,
288
00:19:33,280 --> 00:19:37,000
the sound of scampering feet
is inaudible to us.
289
00:19:40,400 --> 00:19:42,680
But it's loud enough for him.
290
00:19:48,440 --> 00:19:50,440
With the help of a specialist camera
291
00:19:50,440 --> 00:19:54,720
equipped
with 60 highly-sensitive microphones,
292
00:19:54,720 --> 00:19:57,480
we can reveal
what the owl is hearing.
293
00:19:58,480 --> 00:19:59,880
(FAINT SCUFFLING)
294
00:19:59,880 --> 00:20:03,920
The camera visualises
where the vole is beneath the snow.
295
00:20:06,680 --> 00:20:07,680
(SNUFFLES)
296
00:20:18,720 --> 00:20:20,720
And he's off.
297
00:20:24,880 --> 00:20:26,720
(SCUFFLES AND SNIFFS)
298
00:20:31,800 --> 00:20:33,800
(CRUNCHING)
299
00:20:38,200 --> 00:20:40,280
This time he's missed.
300
00:20:46,560 --> 00:20:48,560
(RUSTLING)
301
00:20:49,840 --> 00:20:54,920
Despite his acute hearing,
hunting in snow is a challenge.
302
00:20:57,920 --> 00:21:00,440
The snow not only muffles sound,
303
00:21:00,440 --> 00:21:02,480
it bends it too.
304
00:21:05,400 --> 00:21:08,280
While it appears
as if the vole is here,
305
00:21:08,280 --> 00:21:10,320
it's actually over there.
306
00:21:15,160 --> 00:21:18,800
The only way to defeat
this acoustic illusion,
307
00:21:18,800 --> 00:21:22,240
is for the owl
to get directly above the vole,
308
00:21:22,240 --> 00:21:25,280
where sound is no longer distorted
by the snow.
309
00:21:25,280 --> 00:21:27,320
(WIND GUSTS SOFTLY)
310
00:21:37,720 --> 00:21:41,880
As he flies,
he tracks the sound as it changes.
311
00:21:43,880 --> 00:21:45,960
(SUSPENSEFUL MUSIC)
312
00:21:49,280 --> 00:21:53,160
The closer he gets,
the less the sound is bent.
313
00:21:55,720 --> 00:21:59,760
Directly above the vole,
he can pinpoint his target.
314
00:22:06,080 --> 00:22:07,440
(VOLE SQUEAKS)
315
00:22:18,520 --> 00:22:20,520
The great grey owl's hearing
316
00:22:20,520 --> 00:22:23,000
is its key to securing a meal.
317
00:22:25,160 --> 00:22:28,880
For others,
it's crucial to avoid being eaten.
318
00:22:29,920 --> 00:22:32,320
(CHIRRUPING)
319
00:22:32,320 --> 00:22:35,680
In the Arizona desert,
it's the height of summer.
320
00:22:38,560 --> 00:22:42,520
Daytime temperatures
are over 40 degrees Celsius.
321
00:22:43,840 --> 00:22:46,520
So it's best to be active at night.
322
00:22:48,640 --> 00:22:51,960
Filming under infra-red lights
with a specialist camera...
323
00:22:53,240 --> 00:22:55,240
...we can see everything.
324
00:22:55,240 --> 00:22:57,040
(WIND GUSTS SOFTLY)
325
00:22:59,160 --> 00:23:01,520
But to a kangaroo rat,
326
00:23:01,520 --> 00:23:03,560
it's nearly pitch black.
327
00:23:06,960 --> 00:23:10,720
In the dark,
her most valuable ally is sound.
328
00:23:10,720 --> 00:23:12,760
(WIND GUSTS AND PLANTS RUSTLE)
329
00:23:13,720 --> 00:23:15,280
(SNIFFS)
330
00:23:19,560 --> 00:23:23,560
Her mission tonight is to collect
as many seeds as she can.
331
00:23:26,680 --> 00:23:28,680
But food is scarce...
332
00:23:30,720 --> 00:23:32,720
...and competition fierce.
333
00:23:33,720 --> 00:23:35,080
(SNIFFS)
334
00:23:36,760 --> 00:23:39,800
And, in the dark,
it's hard to spot danger.
335
00:23:40,560 --> 00:23:42,200
(SCUFFLING)
336
00:23:42,200 --> 00:23:44,240
(FOREBODING MUSIC)
337
00:23:45,440 --> 00:23:47,520
(SOFT RUSTLING)
338
00:23:48,600 --> 00:23:52,040
Her ears are 90 times
more sensitive than ours...
339
00:23:52,800 --> 00:23:54,800
and hollow spaces in her skull
340
00:23:54,800 --> 00:23:56,840
act like an echo chamber,
341
00:23:56,840 --> 00:23:59,400
amplifying the faintest of sounds.
342
00:23:59,400 --> 00:24:01,240
(RUSTLING)
343
00:24:02,760 --> 00:24:04,440
(RUSTLING)
344
00:24:05,640 --> 00:24:07,840
But she has
another problem tonight.
345
00:24:08,520 --> 00:24:10,520
(WIND HOWLS)
346
00:24:11,880 --> 00:24:13,880
(WIND GUSTS AND SAND RUSTLES)
347
00:24:13,880 --> 00:24:15,200
Wind.
348
00:24:15,200 --> 00:24:17,200
(WIND HOWLS)
349
00:24:17,960 --> 00:24:20,160
(SAND RUSTLES)
350
00:24:23,200 --> 00:24:26,920
She might not hear a predator
until it's too late.
351
00:24:32,080 --> 00:24:34,480
This time, it's just a stick.
352
00:24:36,080 --> 00:24:39,200
But, in the darkness,
she's right to be cautious.
353
00:24:43,520 --> 00:24:46,760
Snakes can pick up
the sounds of scampering feet
354
00:24:46,760 --> 00:24:48,760
through their lower jaw.
355
00:24:49,520 --> 00:24:51,080
(SOFT RUSTLING)
356
00:24:55,200 --> 00:24:56,200
(SNIFFS)
357
00:24:57,320 --> 00:25:00,320
She's made it
to her favourite feeding spot.
358
00:25:01,800 --> 00:25:04,280
But she's not alone for long.
359
00:25:13,640 --> 00:25:19,600
She warns him to stay away
by drumming her foot on the ground.
360
00:25:19,600 --> 00:25:21,640
(TAPPING)
361
00:25:24,880 --> 00:25:27,920
(TAPPING ECHOES)
He can decipher her size and strength
362
00:25:27,920 --> 00:25:29,960
from her signal.
363
00:25:29,960 --> 00:25:32,000
(TAPPING)
364
00:25:35,320 --> 00:25:37,040
He drums back.
365
00:25:37,040 --> 00:25:39,280
(TAPPING)
366
00:25:39,280 --> 00:25:41,880
It's a battle of beats.
367
00:25:41,880 --> 00:25:43,920
(TAPPING ECHOES)
368
00:25:45,200 --> 00:25:47,520
(TAPPING CONTINUES)
369
00:25:50,560 --> 00:25:51,840
Stalemate.
370
00:25:52,840 --> 00:25:54,880
There's only one
way to resolve this.
371
00:25:55,640 --> 00:25:57,640
(DRAMATIC ORCHESTRAL MUSIC)
372
00:26:17,040 --> 00:26:18,840
(MUSIC FADES)
373
00:26:21,800 --> 00:26:23,800
Dinner time at last.
374
00:26:36,080 --> 00:26:37,840
She hears something.
375
00:26:39,560 --> 00:26:41,560
(OMINOUS MUSIC)
376
00:26:45,200 --> 00:26:48,760
Just out of striking range,
she drums again...
377
00:26:49,560 --> 00:26:51,560
(TAPPING)
378
00:26:52,800 --> 00:26:56,920
...this time to alert the snake
it's been spotted.
379
00:26:58,840 --> 00:27:00,840
But just to be sure...
380
00:27:00,840 --> 00:27:02,280
(SCUFFING AND RUSTLING)
381
00:27:04,120 --> 00:27:06,680
(RUSTLING)
382
00:27:06,680 --> 00:27:08,240
(HISSES)
383
00:27:11,640 --> 00:27:13,640
Message received.
384
00:27:20,760 --> 00:27:23,480
While kangaroo rats
use the ground as a drum
385
00:27:23,480 --> 00:27:25,840
to drive their enemies away...
386
00:27:26,560 --> 00:27:29,840
others are summoned
by seismic sounds.
387
00:27:33,880 --> 00:27:35,880
(LOW GRUMBLING)
388
00:27:38,881 --> 00:27:40,880
(LOW GRUMBLING)
389
00:27:41,880 --> 00:27:43,880
(WIND WHISTLES)
390
00:27:46,200 --> 00:27:48,200
(WHOOSHING)
391
00:27:50,720 --> 00:27:53,320
Amboseli National Park in Kenya.
392
00:27:54,920 --> 00:27:57,840
It hasn't rained here
in nearly a year...
393
00:27:57,840 --> 00:27:59,880
(DEEP GRUMBLING)
394
00:28:01,160 --> 00:28:04,720
...and the dry season
has turned into a severe drought.
395
00:28:06,480 --> 00:28:08,800
(CACOPHONY OF SCREECHING
AND SQUAWKING)
396
00:28:12,320 --> 00:28:15,520
For elephants,
the situation is desperate.
397
00:28:15,520 --> 00:28:18,040
(LOW GRUMBLING)
398
00:28:19,040 --> 00:28:21,760
With no food or water
for miles around,
399
00:28:21,760 --> 00:28:24,640
the matriarch
must wait for a message...
400
00:28:25,680 --> 00:28:28,760
...a sound that will travel
through the ground.
401
00:28:29,520 --> 00:28:31,240
(LOW GRUMBLING)
402
00:28:31,240 --> 00:28:33,280
(HUFFING)
403
00:28:37,520 --> 00:28:40,800
If it arrives,
it will guide them from disaster.
404
00:28:44,680 --> 00:28:47,520
The young calves
are especially vulnerable.
405
00:28:49,480 --> 00:28:50,880
(GRUNTING)
406
00:28:51,680 --> 00:28:56,240
Their mother's milk will dry up
if rain doesn't arrive soon.
407
00:28:58,680 --> 00:29:00,680
(WIND WHISTLES)
408
00:29:03,080 --> 00:29:05,080
(LOW GRUMBLING)
409
00:29:09,760 --> 00:29:11,560
(RUMBLING AND GUSTING)
410
00:29:11,560 --> 00:29:15,800
A hundred miles away,
a storm has broken...
411
00:29:15,800 --> 00:29:17,840
(THUNDERCLAP)
412
00:29:21,440 --> 00:29:23,520
...and the elephants have heard.
413
00:29:24,840 --> 00:29:26,040
(THUNDER RUMBLES)
414
00:29:26,040 --> 00:29:28,000
(LIGHTNING CRACKLES)
415
00:29:29,280 --> 00:29:31,280
Not with their ears...
416
00:29:32,960 --> 00:29:34,880
...but with their feet.
417
00:29:35,600 --> 00:29:37,800
(RAIN SPLATTERS)
418
00:29:38,760 --> 00:29:42,040
The sound of the storm
sends low-frequency vibrations
419
00:29:42,040 --> 00:29:44,480
through the ground.
420
00:29:44,480 --> 00:29:46,960
(AMPLIFIED RUMBLING)
421
00:29:48,800 --> 00:29:50,960
The herd picks up the vibrations
422
00:29:50,960 --> 00:29:54,560
through a network of nerves
in the fatty pads of their feet.
423
00:29:54,560 --> 00:29:56,600
(AMPLIFIED RUMBLING)
424
00:29:57,600 --> 00:29:59,640
(HEAVY SPLASHING)
425
00:30:02,600 --> 00:30:04,160
By lifting one foot,
426
00:30:04,160 --> 00:30:07,400
they can make better contact
on the ground with the other.
427
00:30:09,640 --> 00:30:12,040
(STEADY PATTERING)
428
00:30:12,040 --> 00:30:15,560
It's the message the matriarch
has been waiting for.
429
00:30:15,560 --> 00:30:17,600
(LOW GRUMBLING)
430
00:30:18,640 --> 00:30:21,480
She gives a low "let's go" rumble.
431
00:30:22,960 --> 00:30:24,960
(LOW GRUMBLING)
432
00:30:25,640 --> 00:30:28,000
It's echoed by her sisters.
433
00:30:28,000 --> 00:30:30,040
(GRUNTING AND GRUMBLING)
434
00:30:34,080 --> 00:30:36,640
The journey ahead is treacherous...
435
00:30:38,080 --> 00:30:41,040
...but the sound of the storm
will be their guide.
436
00:30:41,040 --> 00:30:42,480
(TRUMPETING)
437
00:30:44,160 --> 00:30:45,480
(GRUNTS AND SCREECHES)
438
00:30:47,920 --> 00:30:49,920
(LOW GRUMBLING)
439
00:30:53,800 --> 00:30:55,800
(WIND WHOOSHES)
440
00:30:56,520 --> 00:30:59,080
Finally,
after two days on the move...
441
00:31:00,080 --> 00:31:02,080
...they've made it.
442
00:31:04,880 --> 00:31:08,840
Their ability to detect sound
a hundred miles away
443
00:31:08,840 --> 00:31:10,880
has saved the herd.
444
00:31:12,800 --> 00:31:14,800
(THUNDER RUMBLES)
445
00:31:16,760 --> 00:31:20,960
Elephants aren't the only ones
who respond to the sound of rain.
446
00:31:23,920 --> 00:31:26,680
But sometimes
sounds can be deceptive.
447
00:31:30,720 --> 00:31:34,600
In Vancouver, in Canada,
it's also raining.
448
00:31:36,480 --> 00:31:39,080
(HISSING AND PATTERING)
449
00:31:46,160 --> 00:31:48,160
(STEADY PATTERING)
450
00:32:07,400 --> 00:32:11,800
Underground the soil
is teeming with earthworms.
451
00:32:13,600 --> 00:32:18,160
Some rise to the surface
in search of food or mates.
452
00:32:20,920 --> 00:32:24,760
But if the ground isn't wet enough,
they risk drying out.
453
00:32:26,960 --> 00:32:30,080
Sound helps them
pick the opportune moment.
454
00:32:31,680 --> 00:32:33,440
(SPLASHING)
455
00:32:33,440 --> 00:32:35,240
As the rain hits the ground,
456
00:32:35,240 --> 00:32:39,520
it creates vibrations
that travel down into the soil.
457
00:32:44,720 --> 00:32:48,720
They are picked up by sensitive
nerve cells in the worm's skin.
458
00:32:50,800 --> 00:32:54,120
As they rise,
the tumultuous pitter-patter
459
00:32:54,120 --> 00:32:56,160
is music to their senses.
460
00:32:57,360 --> 00:32:59,360
(STEADY PATTERING)
461
00:33:01,240 --> 00:33:04,760
But it is also a sound
that can seal their fate.
462
00:33:06,320 --> 00:33:09,760
Worms aren't the only ones
on the move.
463
00:33:11,640 --> 00:33:13,440
(GULLS SQUAWKING)
464
00:33:13,440 --> 00:33:15,960
Outside the city, a flock of gulls
465
00:33:15,960 --> 00:33:19,200
are co-ordinating their
morning departure from the roost.
466
00:33:19,200 --> 00:33:22,240
(CACOPHONY OF SQUAWKING
AND SCREECHING)
467
00:33:32,040 --> 00:33:36,160
Thanks to the rain, they've got
a special meal on the menu today.
468
00:33:37,600 --> 00:33:38,920
Worms!
469
00:33:40,760 --> 00:33:43,160
But by the time they arrive,
470
00:33:43,160 --> 00:33:45,480
the downpour is over...
471
00:33:48,640 --> 00:33:51,520
...and the worms
are already retreating.
472
00:33:56,000 --> 00:33:58,160
Dining options look scarce...
473
00:33:59,320 --> 00:34:02,080
...but the gulls have a crafty trick.
474
00:34:04,280 --> 00:34:07,160
For it to work,
they must find their rhythm.
475
00:34:07,840 --> 00:34:09,840
(SOFT RHYTHMIC TAPPING)
476
00:34:15,520 --> 00:34:20,520
Paddling creates vibrations that
likely mimics the sound of rain.
477
00:34:24,520 --> 00:34:27,240
It's a dance of deception.
478
00:34:29,120 --> 00:34:32,360
(MUFFLED TAPPING)
The worms rise once again.
479
00:34:32,360 --> 00:34:34,400
(MUFFLED TAPPING)
480
00:34:39,320 --> 00:34:42,440
They can't resist
the rhythmic rain dance.
481
00:34:48,520 --> 00:34:50,000
(RHYTHMIC TAPPING)
482
00:35:00,880 --> 00:35:02,440
(STEADY PATTERING)
483
00:35:02,440 --> 00:35:06,280
Another shower
brings an acoustic climax.
484
00:35:07,120 --> 00:35:08,760
(RHYTHMIC TAPPING)
485
00:35:14,560 --> 00:35:17,160
The rainy season
will last all winter,
486
00:35:17,160 --> 00:35:20,320
so worms are on the menu
until spring.
487
00:35:23,840 --> 00:35:27,040
For these gulls,
the cunning use of sound
488
00:35:27,040 --> 00:35:29,280
helps them win an easy meal.
489
00:35:34,200 --> 00:35:36,200
But in other parts of the world,
490
00:35:36,200 --> 00:35:39,720
the stakes are higher
for both predator and prey.
491
00:35:41,880 --> 00:35:43,880
(LOW GRUMBLING)
492
00:35:46,885 --> 00:35:48,880
(LOW GRUMBLING)
493
00:35:49,880 --> 00:35:51,200
(INSECTS CHIRRUPING)
494
00:35:51,200 --> 00:35:52,760
(LION GRUNTS)
495
00:35:52,760 --> 00:35:55,960
As night falls
on the African savanna,
496
00:35:55,960 --> 00:36:00,080
the air is filled
with sounds of a formidable hunter.
497
00:36:01,720 --> 00:36:03,440
(LIONS BELLOW)
498
00:36:04,760 --> 00:36:06,920
(BELLOWING CONTINUES)
499
00:36:07,960 --> 00:36:10,480
(BELLOWING)
500
00:36:11,360 --> 00:36:14,880
(DEEP RUMBLING GROWL)
501
00:36:14,880 --> 00:36:16,960
On the other side of the territory,
502
00:36:16,960 --> 00:36:20,320
the females of the pride
are preparing to hunt.
503
00:36:22,280 --> 00:36:26,400
Over 30 strong,
they must make a kill every night.
504
00:36:30,000 --> 00:36:32,000
(SOFT GROWLING)
505
00:36:32,000 --> 00:36:34,760
Close by, a hyena den.
506
00:36:34,760 --> 00:36:36,880
(SOFT SQUEAKING)
507
00:36:38,920 --> 00:36:42,840
The adults must also head out
to find their next meal.
508
00:36:47,480 --> 00:36:51,080
Hyenas will often steal
if the opportunity arises...
509
00:36:53,640 --> 00:36:56,360
...even from their deadliest foes.
510
00:36:57,600 --> 00:37:02,040
But separated from the males,
this pride is vulnerable.
511
00:37:06,280 --> 00:37:10,960
For a successful heist,
the hyenas rely on sound.
512
00:37:13,560 --> 00:37:16,320
First,
the lionesses need to make a kill.
513
00:37:16,320 --> 00:37:18,360
(GROWLING AND GRUNTING)
514
00:37:18,360 --> 00:37:21,880
With a noisy family in tow,
that can be tricky.
515
00:37:21,880 --> 00:37:23,520
(YOWLING)
516
00:37:23,520 --> 00:37:25,400
(MOOING AND GRUNTING)
517
00:37:25,400 --> 00:37:28,160
Wildebeest have gathered
together for safety.
518
00:37:28,160 --> 00:37:30,320
(MOOING AND GRUNTING)
519
00:37:34,120 --> 00:37:37,880
In the darkness,
they have to rely on their hearing.
520
00:37:40,040 --> 00:37:42,040
(DISTANT MOOING AND GRUNTING)
521
00:37:50,720 --> 00:37:53,760
The lioness
makes a stealthy approach...
522
00:38:02,760 --> 00:38:05,000
...but there is a problem
523
00:38:05,000 --> 00:38:07,440
(SNUFFLING AND RATTLING)
524
00:38:07,440 --> 00:38:11,480
A porcupine is a playful distraction
for the youngsters.
525
00:38:11,480 --> 00:38:13,240
(QUILLS RATTLE)
526
00:38:13,240 --> 00:38:16,160
The sound of shaking quills
is a warning...
527
00:38:16,160 --> 00:38:17,600
(QUILLS RATTLE)
528
00:38:17,600 --> 00:38:19,800
(SNARLING)
529
00:38:19,800 --> 00:38:21,480
(YOWLING)
530
00:38:22,240 --> 00:38:24,720
...and the wildebeest
have heard the commotion.
531
00:38:29,240 --> 00:38:31,240
(THUNDERING HOOVES)
532
00:38:35,160 --> 00:38:37,160
They have blown it for her.
533
00:38:38,960 --> 00:38:40,440
(GRUNTING AND GROWLING)
534
00:38:40,440 --> 00:38:44,320
They will take the rattle of shaking
quills more seriously next time.
535
00:38:46,280 --> 00:38:48,400
(MOOING AND GRUNTING)
536
00:38:54,360 --> 00:38:57,520
The pride
have detected another opportunity.
537
00:39:00,200 --> 00:39:02,200
A warthog burrow.
538
00:39:08,920 --> 00:39:10,080
(GROWLING)
539
00:39:10,080 --> 00:39:12,120
(WARTHOG SCREECHES)
540
00:39:12,120 --> 00:39:14,120
(SNARLING)
541
00:39:14,120 --> 00:39:16,160
(WARTHOG SCREECHES)
542
00:39:17,680 --> 00:39:19,680
(SLURPING AND CRUNCHING)
543
00:39:20,520 --> 00:39:24,920
The sound of their feast
carries far in the cool night air...
544
00:39:26,920 --> 00:39:29,320
...and the hyenas have heard.
545
00:39:30,440 --> 00:39:32,440
(CRUNCHING AND SLURPING)
546
00:39:38,200 --> 00:39:42,840
But there are too many lions here
to steal this meal alone.
547
00:39:46,920 --> 00:39:49,480
She will need the full force
of her clan.
548
00:39:50,480 --> 00:39:52,920
(LOW WHOOPING CALL)
549
00:39:52,920 --> 00:39:56,000
She sends a message
to rally her troops.
550
00:39:56,000 --> 00:39:58,040
(WHOOPING CALL)
551
00:40:02,440 --> 00:40:04,440
(WHOOPING CALL)
552
00:40:05,920 --> 00:40:09,840
Directed at the ground, her message
resonates further and faster
553
00:40:09,840 --> 00:40:11,720
than it would through air.
554
00:40:11,720 --> 00:40:13,280
(CHITTERING AND SQUEAKING)
555
00:40:13,280 --> 00:40:15,320
(CHITTERING)
556
00:40:16,720 --> 00:40:18,720
(HIGH-PITCHING SQUEAKING)
557
00:40:20,720 --> 00:40:22,160
(CHITTERING)
558
00:40:22,160 --> 00:40:24,560
Even with numbers now on their side,
559
00:40:24,560 --> 00:40:27,680
sound is critical
if they're to steal this meal.
560
00:40:27,680 --> 00:40:29,720
(WHOOPING AND CHITTERING)
561
00:40:31,320 --> 00:40:33,760
(SNARLING)
562
00:40:33,760 --> 00:40:36,200
Calling unites the clan.
563
00:40:36,200 --> 00:40:38,360
They must approach
as a tight-knit group,
564
00:40:38,360 --> 00:40:40,720
making as much noise as they can.
565
00:40:40,720 --> 00:40:43,000
(CACOPHONY OF WHOOPING AND
CHITTERING)
566
00:40:48,000 --> 00:40:49,840
(LOW GROWL)
567
00:40:49,840 --> 00:40:51,880
(HYENAS SCREECH)
568
00:40:55,360 --> 00:40:57,360
(HYENA SCREECHES)
569
00:40:59,800 --> 00:41:01,800
(LION SNARLS)
570
00:41:03,600 --> 00:41:05,120
(YELPING AND WHIMPERING)
571
00:41:05,120 --> 00:41:06,840
(SNARLS)
572
00:41:07,680 --> 00:41:09,680
(SCREECHING AND ROARING)
573
00:41:11,200 --> 00:41:14,680
The noise of the battle
has alerted more lions.
574
00:41:16,080 --> 00:41:17,440
(SNARLING)
575
00:41:17,440 --> 00:41:18,760
(FRANTIC SCREECHING)
576
00:41:19,640 --> 00:41:21,640
(YOWLING)
577
00:41:22,360 --> 00:41:23,960
(YELPING)
578
00:41:23,960 --> 00:41:25,240
(LOW GROWL)
579
00:41:25,240 --> 00:41:28,120
It's game over for the hyenas.
580
00:41:28,120 --> 00:41:30,000
(HIGH-PITCHED SCREECHING)
581
00:41:30,880 --> 00:41:32,880
The brothers have returned.
582
00:41:33,720 --> 00:41:35,960
(YELPING)
583
00:41:42,720 --> 00:41:44,720
(BIRDS TWITTERING)
584
00:41:49,880 --> 00:41:54,040
After a successful night,
the pride is well fed.
585
00:41:57,560 --> 00:42:00,120
Some will spend the day dozing.
586
00:42:03,200 --> 00:42:06,480
But for others,
it's time to reaffirm
587
00:42:06,480 --> 00:42:08,880
the prides' ownership
of their territory.
588
00:42:08,880 --> 00:42:09,960
(GROWLS HOARSELY)
589
00:42:15,000 --> 00:42:16,000
(GRUNTS)
590
00:42:23,760 --> 00:42:26,520
We are only
just beginning to understand
591
00:42:26,520 --> 00:42:29,560
the many ways that animals use sound.
592
00:42:32,480 --> 00:42:35,160
For us,
the sound of the natural world
593
00:42:35,160 --> 00:42:38,080
is a source of peace
and tranquillity.
594
00:42:40,120 --> 00:42:44,280
For other animals,
it's a tool they have to master
595
00:42:44,280 --> 00:42:47,160
in order to hunt and survive.
596
00:43:06,680 --> 00:43:09,400
MAN: Yep.
WOMAN: It is so cold out here.
597
00:43:10,240 --> 00:43:13,120
MAN: I think just over here
to the left looks pretty good.
598
00:43:13,120 --> 00:43:15,640
OK.
We have picture.
599
00:43:15,640 --> 00:43:19,240
Our film crew have come
to Manitoba in Canada
600
00:43:19,240 --> 00:43:21,560
in search of the great grey owl.
601
00:43:23,120 --> 00:43:26,920
Yeh, that looks like
- a promising spot.
- Oh, OK.
602
00:43:27,880 --> 00:43:30,280
I think there were
some owls here last week.
603
00:43:32,120 --> 00:43:33,920
But, like many of our shoots,
604
00:43:33,920 --> 00:43:37,520
we rely on the work of others
who've come before us.
605
00:43:39,280 --> 00:43:41,840
For years, scientists have wondered
606
00:43:41,840 --> 00:43:46,640
exactly how the owl penetrates the
layers of snow that conceal its prey.
607
00:43:51,040 --> 00:43:55,080
Biologists Chris Clark and Jim Duncan
are on a mission.
608
00:43:55,080 --> 00:43:57,720
This is excellent.
There's a plunge hole right here
609
00:43:57,720 --> 00:44:00,200
where the great grey hit the snow.
610
00:44:01,840 --> 00:44:04,360
They are armed with a special tool.
611
00:44:04,360 --> 00:44:06,000
I'll grab the battery.
OK.
612
00:44:06,000 --> 00:44:08,080
An acoustic camera.
613
00:44:08,080 --> 00:44:12,160
This version
has 40 sensitive microphones
614
00:44:12,160 --> 00:44:17,680
that pinpoint sound, while a tiny
camera films its exact location.
615
00:44:18,480 --> 00:44:21,720
It should allow them to see exactly
what the owl is hearing.
616
00:44:21,720 --> 00:44:23,800
(RUSTLING)
617
00:44:23,800 --> 00:44:26,320
This camera is wonderful
because it visualises
618
00:44:26,320 --> 00:44:28,280
where the sound is coming from.
619
00:44:28,280 --> 00:44:30,320
So I'm able to look and see,
620
00:44:30,320 --> 00:44:32,760
how does the environment
affect the sound.
621
00:44:32,760 --> 00:44:34,320
(MUFFLED RUSTLING)
622
00:44:38,200 --> 00:44:40,560
Snow is a formidable barrier.
623
00:44:44,360 --> 00:44:47,840
For the vole,
it's a cloak of invisibility.
624
00:44:47,840 --> 00:44:49,400
(SNUFFLING)
625
00:44:49,400 --> 00:44:54,480
To the owl, it's an obstacle that
must be overcome by hearing alone.
626
00:44:55,640 --> 00:44:57,680
52cm?
Yeah.
627
00:44:58,840 --> 00:45:01,920
The researchers
bury a speaker under the snow
628
00:45:01,920 --> 00:45:04,640
which will play the sound
of a foraging vole.
629
00:45:04,640 --> 00:45:06,680
(HIGH-PITCHED SQUEAKING)
630
00:45:07,560 --> 00:45:09,600
They will bury it
at different depths
631
00:45:09,600 --> 00:45:13,640
and use the acoustic camera to see
how the snow affects the sound.
632
00:45:15,520 --> 00:45:17,960
The speaker is now visible
in the camera view.
633
00:45:17,960 --> 00:45:20,280
This black thing right here,
that's the speaker.
634
00:45:20,280 --> 00:45:22,840
And the acoustic camera,
that blob of colour,
635
00:45:22,840 --> 00:45:25,360
is localising the sound
coming from the speaker.
636
00:45:27,600 --> 00:45:30,200
But the playback
from the snow-covered speaker
637
00:45:30,200 --> 00:45:32,200
reveals a surprise
638
00:45:32,200 --> 00:45:36,160
the snow dramatically alters
the location of the sound.
639
00:45:37,320 --> 00:45:41,160
(MUFFLED SQUEAKING)
That metre stick
is above the speaker
640
00:45:41,160 --> 00:45:44,320
and there's a blob of colour
where the acoustic camera
641
00:45:44,320 --> 00:45:47,080
perceives the sound
to be coming out of the snow.
642
00:45:47,080 --> 00:45:51,000
It's amazing. The snow is bending
the path that the sound is taking.
643
00:45:51,800 --> 00:45:56,400
As a result, if an owl were to try
to localise the sound of the vole,
644
00:45:56,400 --> 00:46:00,280
from where it hears the sound, it
would miss and hit the wrong spot.
645
00:46:01,480 --> 00:46:05,960
But Chris realises there is a way
for the owl to overcome this problem.
646
00:46:13,000 --> 00:46:14,600
As the owl is coming in,
647
00:46:14,600 --> 00:46:17,560
it's listening to pinpoint
the location of the vole.
648
00:46:19,600 --> 00:46:22,880
Because of the snow,
it sounds like the vole is here...
649
00:46:24,200 --> 00:46:26,200
...when it's actually there.
650
00:46:28,680 --> 00:46:30,760
But as the owl gets closer,
651
00:46:30,760 --> 00:46:34,560
it starts to overcome the effect
that snow has on the sound.
652
00:46:38,280 --> 00:46:43,240
For the first time Chris realises
why, at this point in its attack,
653
00:46:43,240 --> 00:46:45,320
the great grey owl hovers.
654
00:46:46,880 --> 00:46:51,560
The acoustic camera reveals that
it's now in the perfect position.
655
00:46:53,240 --> 00:46:56,360
The sweet spot for the owl
is when it's right above the prey.
656
00:46:57,360 --> 00:47:00,400
Directly above the vole,
the snow doesn't bend the sound
657
00:47:00,400 --> 00:47:02,760
so the owl can pinpoint
exactly where the vole is.
658
00:47:04,480 --> 00:47:06,240
(SQUEAKING)
659
00:47:06,240 --> 00:47:09,080
Only then does the owl plunge.
660
00:47:10,360 --> 00:47:11,680
(VOLE SQUEAKS)
661
00:47:11,680 --> 00:47:13,080
Wow!
662
00:47:13,080 --> 00:47:16,160
It's completely amazing that
these owls can localise their prey
663
00:47:16,160 --> 00:47:17,800
just by listening.
664
00:47:22,960 --> 00:47:25,840
I love doing this kind of research
and, through that,
665
00:47:25,840 --> 00:47:28,520
understand the natural world
and the amazing things
666
00:47:28,520 --> 00:47:31,160
that species
like the great grey owl are doing.
667
00:47:33,480 --> 00:47:35,960
For decades,
researchers had believed
668
00:47:35,960 --> 00:47:40,160
that there was more to discover about
the great grey owl's acute hearing.
669
00:47:42,560 --> 00:47:45,560
Now they've finally uncovered
the complex ways
670
00:47:45,560 --> 00:47:49,360
it uses sound
to hunt its prey in snow.
671
00:47:52,560 --> 00:47:54,080
Alrighty.
672
00:47:56,280 --> 00:47:58,120
(THUNDERCLAP)
(CROAKS)
673
00:47:58,800 --> 00:48:01,280
As the story of sound continues...
674
00:48:01,280 --> 00:48:02,560
(DEEP HUMMING)
675
00:48:03,560 --> 00:48:08,240
...we reveal how animals use sound
to fight off competition...
676
00:48:08,240 --> 00:48:09,320
(WHOOPING)
677
00:48:09,320 --> 00:48:11,120
(RAPID THUDDING)
678
00:48:11,120 --> 00:48:14,640
...and use songs
in their quest to win a mate.
679
00:48:14,640 --> 00:48:16,120
(STRIDENT SQUAWKS)
680
00:48:17,800 --> 00:48:19,360
(INSECTS CHIRRUPING)
681
00:48:21,000 --> 00:48:23,000
(SOFT RUMBLING ROAR)
682
00:48:23,000 --> 00:48:25,040
(SQUAWKING AND CHIRRUPING)
683
00:48:25,040 --> 00:48:27,080
(WHOOPING CALL)
684
00:48:29,000 --> 00:48:32,160
(ANIMAL SOUNDS CONTINUE)
685
00:48:33,800 --> 00:48:35,920
AccessibleCustomerService@sky.uk
46185
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