Original subtitles

♪♪

Narrator: ANIMALS...

DO THE MOST INCREDIBLE THINGS.

[ GOAT BLEATS ]

LIKE THIS...

AND THIS.

I BET YOU'RE WONDERING, "HOW DO THEY DO THAT?"

WE'RE REVEALING ANIMALS' BIGGEST SECRETS, LIKE...

HOW DO DOGS SNIFF OUT UNDERWATER TARGETS?

HOW DO SLOTHS AVOID PERMANENT HEADRUSH?

AND WHAT MAKES THESE BIG BIRDS NATURE'S BEST MARATHON RUNNERS?

THESE WONDERS AND MORE.

--Captions by VITAC-- www.vitac.com

CAPTIONS PAID FOR BY DISCOVERY COMMUNICATIONS

SOME DOGS ARE SO MUCH MORE THAN PETS.

THEY'RE HEROES.

SEARCH-AND-RESCUE DOGS SAVE THOUSANDS OF LIVES EVERY YEAR.

WHETHER IT'S AN AVALANCHE, DISASTER ZONE,

OR THE MIDDLE OF NOWHERE, FIDO WILL FIND YOU.

BUT NOT ALL CANINE SEARCHERS ARE ON LAND.

SOME DOGS CAN FIND YOU EVEN IF YOU'RE UNDERWATER.

THERE ARE AROUND 80 MILLION DOGS BOUNCING AROUND AMERICAN HOMES,

AND EVERY DOG HAS A SUPERPOWER IN ITS NOSE.

THEIR SENSE OF SMELL CAN BE 100,000 TIMES

MORE POWERFUL THAN HUMANS',

AND SO POWERFUL SOME CAN EVEN SMELL A TASTY CHICKEN SANDWICH

FROM TWO MILES AWAY.

THIS SUPER-SENSE COMBINED WITH A TRAINABLE INTELLIGENCE

HAS GIVEN BIRTH TO A NEW BREED OF RESCUE SUPERSTARS.

MEET INDY, A SEARCH-AND-RESCUE DOG IN TRAINING.

Berry: HE'S A PUPPY, AS YOU CAN SEE.

HE STILL LIKES TO PLAY A LOT,

BUT THERE'S SOMETHING HE LOVES EVEN MORE,

AND THAT'S FINDING SCENT.

OH, GOOD BOY. GOOD BOY.

Narrator: MARY HAS BEEN TRAINING INDY FOR NEARLY TWO YEARS,

AND THIS CLEVER CANINE IS CLOSE TO GRADUATING TOP OF HIS CLASS.

GOOD BOY!

BUT THE ULTIMATE TEST IS YET TO COME --

FINDING SCENT UNDERWATER.

WE'RE GOING TO PUSH INDY'S NOSE

AND SCENTING ABILITY TO THE LIMIT

BY PLACING THIS BOOT,

WHICH HAS HUMAN DECOMPOSING ODOR IN IT,

AND WE'RE GOING TO PUT IT IN THE LAKE

AND SEE IF HE CAN FIND IT.

Narrator: TIME TO SUIT UP.

ON THE OTHER SIDE OF THE LAKE, NEARLY 1,500 FEET AWAY

AND COMPLETELY OUT OF INDY'S SIGHT,

THE DIVE TEAM HEADS OUT WITH THE BOOT

AND SINKS IT 15 FEET DOWN.

IT'S GO TIME. LET'S GO.

GOOD BOY.

Narrator: INDY'S NOSE IS OFF TO WORK.

MARY SYSTEMATICALLY CRISS-CROSSES THE LAKE,

ALLOWING INDY TO SMELL THE WHOLE AREA,

JUST AS HE WOULD DO IN A REAL-LIFE SEARCH.

AND, INCREDIBLY, EVEN THOUGH THE BOOT IS DEEP UNDER

THIS VAST, EXPANSIVE WATER, THERE WILL BE A SCENT SOMEWHERE.

REALLY SMALL GAS BUBBLES ARE BEING RELEASED

FROM THE SOURCE RIGHT NOW,

AND THAT'S WHAT THE DOG IS DETECTING

WHEN IT COMES TO THE SURFACE.

Narrator: NO HUMAN COULD EVER PICK UP THESE TINY BUBBLES.

IT'S LIKE TRYING TO SNIFF OUT A PAIR OF SOCKS

IN AN AREA THE SIZE OF MANHATTAN.

BUT INDY'S NOSE HAS A CHANCE BECAUSE IT IS EQUIPPED

WITH INCREDIBLE SCENT-HUNTING SKILLS.

HIS NOSE SPLITS THE FLOW OF AIR INTO TWO SEPARATE STREAMS --

ONE FOR BREATHING, AND ONE FOR SMELLING,

ALLOWING HIM TO FILTER OUT THE MOST MINUTE AND DISTANT ODORS.

AND USING THIS SENSATIONAL SMELLING SENSE,

INDY'S ONTO SOMETHING.

HIS TAIL IS WAGGING, HE'S DOING SOME BARKING.

[ INDY WHINES ]

Narrator: BUT IT'S ONE THING GETTING THE SCENT.

IT'S ANOTHER HOMING IN ON A TARGET

THAT'S SOMEWHERE 15 FEET BELOW THE SURFACE.

SO HOW WILL INDY FIGURE OUT WHERE THE ODOR IS?

♪♪

WELL, HIS NOSE HAS ANOTHER SUPER-ABILITY.

EACH NOSTRIL CAN BE CONTROLLED INDEPENDENTLY,

ALLOWING INDY TO DETECT PRECISELY THE DIRECTION

THAT THE SMELL IS COMING FROM.

THIS MEANS HE CAN CREATE A SCENT MAP,

LEADING HIM TO WHERE THE SMELL IS STRONGEST

AND RIGHT TOWARDS HIS TARGET.

[ INDY BARKS ]

OH, YOU'VE GOT SOMETHING NOW.

GOOD BOY.

Narrator: INDY SHOWS HIS FELLOW RESCUE TEAM

THE WAY TO STEER BY MOVING AROUND THE BOAT,

POINTING THE WAY WITH HIS NOSE

AND BARKING TO TELL MARY THEY'RE GETTING CLOSER.

IF HE'S CONFIDENT, I'M CONFIDENT.

Narrator: IT'S TAKEN 20 MINUTES,

AND INDY INDICATES THEY'RE RIGHT ON TOP OF THE TARGET.

[ INDY BARKS ]

IT MUST BE RIGHT ON A JACKPOT

'CAUSE HE IS GOING NUTS IN HERE.

[ INDY BARKS AND WHINES ]

Narrator: INDY'S BARKING MEANS, "BRING IN THE DIVE TEAM."

♪♪

GOOD JOB, INDY!

CONGRATULATIONS! GOOD JOB!

WHAT A GOOD BOY!

WHOO-HOO!

YAY, INDY!

Narrator: INCREDIBLE.

WATER IS NO BARRIER TO THIS CANINE.

HE'S TRACKED DOWN SCENT PARTICLES

WHICH TRAVEL FROM DEEP UNDER THE WATER 15 FEET TO THE SURFACE

AND FOUND IT WITHIN A 17-SQUARE-MILE LAKE.

GIVE THAT NOSE A CAPE BECAUSE IT IS TRULY SUPER.

OR JUST GIVE INDY HIS FAVORITE TOY.

HE'LL LIKE THAT BETTER.

[ INSECTS BUZZING ]

AS THE SUN GOES DOWN ON A BALMY SUMMER'S EVENING,

ALL ACROSS ASIA AND AMERICA, MILLIONS OF TINY ANIMALS

ARE PUTTING ON ONE OF THE GREATEST SHOWS ON EARTH.

AS DAZZLING AS ANYTHING ON BROADWAY,

THIS SPECTACULAR DISPLAY IS COURTESY

OF SOME OF NATURE'S BRIGHTEST STARS --

FIREFLIES.

THESE LEADING LIGHTS OF THE ANIMAL KINGDOM

ALWAYS GET GLOWING REVIEWS. BUT...

♪♪

DESPITE THE NAME, FIREFLIES AREN'T FLIES,

AND THEY'RE NOT ON FIRE.

THEY'RE A TYPE OF BEETLE

THAT PRODUCES THE MOST EFFICIENT LIGHT IN THE WORLD.

ORDINARY LIGHT BULBS LOSE 90% OF THEIR ENERGY TO HEAT.

IF FIREFLIES CREATED THIS KIND OF HEAT,

THEY WOULD SIMPLY BURST INTO FLAMES.

BUT AS ALMOST 100% OF THE CHEMICAL ENERGY

THEY EMIT IS LIGHT,

THESE BRIGHT SPARKS CREATE LIGHT THAT IS COLD.

BRILLIANT!

INSIDE THEIR BODIES IS A COMPOUND CALLED LUCIFERIN.

AS OXYGEN RUSHES INTO A FIREFLY'S ABDOMEN,

IT REACTS WITH THE LUCIFERIN, CREATING LIGHT WITHOUT HEAT.

A FIREFLY CAN VARY THE LENGTH AND RHYTHM OF THE FLASH

BY OPENING AND CLOSING TUBES CALLED TRACHEOLES

THAT LET OXYGEN INTO ITS LIGHT-ORGAN.

SO WHY ALL THE FLASHING?

WELL, IT'S A TYPE OF COMMUNICATION.

BUT THEY'RE NOT ENGAGING IN LIGHT CONVERSATION.

THESE FIREFLIES ARE LOOKING FOR LOVE.

THE MALES FLASH FIRST, SAYING THEY'RE READY TO MATE.

THE FASTER THE FLASHING,

THE MORE ATTRACTIVE THEY ARE TO A FEMALE WHO JUST MIGHT,

IF SHE'S INTERESTED, GIVE HIM A FLASH BACK.

SHE'S SAYING, "COME ON, BABY.

LIGHT MY FIRE...

FLY."

EACH SPECIES HAS ITS OWN UNIQUE CODED FLASHING SYSTEM.

BUT MALES BEWARE --

THERE'S ONE WHOSE FEMALE USES ITS TINY TORCH AS A TRAP.

THE PHOTURIS FIREFLY HAS LEARNED TO MIMIC THE FLASHING DISPLAY

OF OTHER FIREFLY SPECIES TO LURE IN AMOROUS MALES

AND THEN EAT THEM.

YES, IF YOU FALL FOR THIS FIREFLY FEMME FATALE,

IT'S LIGHTS OUT.

MMM, A DINNER DATE.

HOW ROMANTIC.

[ OWL HOOTING ]

COMING UP --

A PREDATORY PELICAN PARTY...

HAIRY HANGERS...

AND A BIG-BIRD MARATHON.

Narrator: ON THE PLAINS OF AFRICA, THESE LIONS ARE EYEING UP

WHAT LOOKS LIKE AN OVERSIZED TURKEY,

BUT THEY'LL HAVE A JOB CATCHING THIS HANDSOME GUY.

OSTRICHES CAN'T FLY, BUT THAT DOESN'T MATTER

BECAUSE THIS IS THE FASTEST ANIMAL ON TWO LEGS,

WITH A TOP SPEED OF 45 MILES AN HOUR.

AND THEY COMBINE THAT HIGH SPEED WITH INCREDIBLE ENDURANCE.

WHEREAS LIONS CAN ONLY SPRINT FOR A MATTER OF SECONDS,

OSTRICHES CAN RUN AND RUN AND RUN

FOR MORE THAN HALF AN HOUR.

[ LION ROARS ]

LATERS, KITTY CAT.

TO REVEAL THE SECRET OF OSTRICHES' INCREDIBLE ENDURANCE,

WE'VE COME TO CALIFORNIA'S CENTRAL COAST TO OSTRICHLAND,

HOME TO 50 AMAZING OSTRICHES.

THEIR DAY JOB IS WOWING CROWDS

THAT FLOCK HERE TO SEE THESE BIG BIRDS,

AND KEEPER BLAKE FOWLER KNOWS THE STUFF THEY LOVE TO SHOW OFF

IS THEIR SPRINTING SKILLS.

OSTRICHES -- THEY JUST TRULY DO LOVE TO RUN.

THAT'S REALLY WHAT THEY LIKE.

Narrator: TO TEST HOW OSTRICHES CAN COVER SO MUCH DISTANCE,

BLAKE IS SETTING UP A HIGH-SPEED CAMERA

TO CAPTURE THEIR SPRINTING SECRETS IN SLOW-MOTION...

Fowler: OKAY, GUYS. LET'S DO IT.

Narrator: ...AND USING A QUAD-BIKE TO HERD

THE SPRINTING OSTRICHES TOWARDS THE CAMERA.

♪♪

Fowler: JUST FOLLOW ME AROUND THIS WAY.

Narrator: WATCH THE BIRDIE.

GOTCHA!

THAT'S A GREAT SHOT.

MAN, THAT IS IMPRESSIVE.

Narrator: LOOKING BACK AT THE FOOTAGE,

THERE'S SOMETHING ABOUT THE BIRD'S RUNNING

THAT IS OFF THE SCALE.

YOU CAN SEE HOW BIG THAT STRIDE REALLY IS.

LOOK AT THE STRIDE.

THAT'S GNARLY.

GET THE TAPE MEASURE, BLAKE.

LET'S SEE HOW BIG THAT STRIDE IS.

WOW. I'M AT ABOUT THREE METERS HERE.

THAT'S PRETTY IMPRESSIVE.

IT HAS BEEN COMPARED TO, LIKE, THE LENGTH OF A CAR --

UP TO FOUR METERS.

Narrator: THAT'S 13 FEET --

TWICE THE STRIDE OF AN OLYMPIC SPRINTER.

WITH THOSE MEGA-STRIDES, IT'S NO WONDER

THEY CAN COVER VAST DISTANCES QUICKLY,

BUT WHAT'S PROVIDING THE POWER BEHIND THOSE LEGS?

IT CAN'T BE MUSCLE.

LOOK AT HOW SKINNY THEY ARE.

WEIRDLY, STUDYING THE LEG ANATOMY REVEALS

THAT ALTHOUGH IT LOOKS LIKE A LEG,

IT'S ACTUALLY ONE OF NATURE'S BIGGEST FEET.

Fowler: IT'S REALLY QUITE AMAZING,

BUT WHAT'S ACTUALLY THEIR KNEE IS THEIR ANKLE.

Narrator: COMPARED TO US, THE OSTRICH KNEE IS MUCH HIGHER,

AND BELOW IS ALL FOOT.

THE BACKWARDS-BENDING JOINT IS AN ANKLE, HIGH OFF THE GROUND.

AND WHAT LOOKS LIKE AN ANKLE IS AN OSTRICH TOE JOINT.

SO HOW CAN OVERSIZED FEET TURN A BIRD

INTO A STRIDING SUPERSTAR?

WELL, INSIDE THOSE MASSIVE FEET, INSTEAD OF MUSCLE

ARE ENORMOUS TENDONS.

TENDONS ARE STRETCHY FIBERS THAT ATTACH MUSCLES TO BONES.

IN OSTRICH FEET, THESE TENDONS ARE TWICE AS ELASTIC AS OUR OWN,

AND THEY ARE MASSIVE.

THEY ACT LIKE ENORMOUS RUBBER BANDS,

STORING ELASTIC ENERGY

AND THEN RELEASING IT TO GIVE OSTRICHES

A LITERAL SPRING IN THEIR STEP.

BOTH FEET OFF THE GROUND AT THE SAME TIME.

IT'S LIKE THEY'RE FLYING.

Narrator: AND BECAUSE TENDONS CREATE THEIR OWN ELASTIC ENERGY,

THEY DON'T NEED AS MUCH ENERGY FROM THE BODY AS MUSCLES DO,

WHICH MAKES THEM EXTREMELY EFFICIENT.

IT'S THE SAME REASON THAT JUMPING HIGH ON YOUR OWN

OVER AND OVER IS EXHAUSTING,

BUT ADD THE HELP OF A SPRINGED POGO STICK,

AND YOU CAN JUMP HIGHER AND LONGER

WITHOUT GETTING TIRED.

IN FACT, THE BIRD'S BOUNCING, BOUNDING STRIDES ARE SO POWERFUL

THAT AN OSTRICH COULD RUN AN ENTIRE 26-MILE MARATHON

IN JUST 40 MINUTES USING HALF THE CALORIES A HUMAN WOULD.

WOW!

Fowler: IT'S JUST SO EFFORTLESS.

THEY'RE REALLY TWICE AS EFFICIENT

WHEN IT COMES TO RUNNING.

[ BIRDS CHIRPING ]

Narrator: COMING UP --

THE SECRET TO LIFE UPSIDE DOWN,

AND HOW THERE'S NO ESCAPE FROM THE PELICAN PACK.

♪♪

Narrator: NOTHING HANGS OUT LIKE A SLOTH.

IT SPENDS 90% OF ITS LIFE DANGLING UPSIDE DOWN FROM TREES.

IF WE DID THAT, WE'D GET SERIOUS HEADRUSH,

BREATHLESSNESS, AND MUSCLE ACHE.

SOMEHOW, THESE GUYS DO IT ALL DAY, EVERY DAY

WITH A SMILE.

INCREDIBLY CUTE AND FAMOUSLY LAZY,

SLOTHS HAVE A TOP SPEED OF AROUND 1/10 OF A MILE AN HOUR.

THAT'S SLIGHTLY FASTER THAN A LITERAL SNAIL'S PACE.

WHEN THEY ARE AWAKE, THEY SPEND THEIR TIME

EATING FRUIT OR LEAVES

AND REARING THEIR YOUNG.

BUT THERE'S NOT MUCH OF THAT BECAUSE THEY CAN SLEEP

UP TO 20 HOURS A DAY,

AND THEY DO ALL THIS HANGING UPSIDE DOWN IN TREES.

IN FACT, THE ONLY THING SLOTHS STOP HANGING FOR

IS...TO GO TO THE TOILET.

AND THEY ONLY DO THAT ONCE A WEEK.

TO FIND OUT HOW SLOTHS HANG FOR DAYS ON END,

WE'VE COME TO CINCINNATI ZOO

TO SEE A PARTICULARLY ADORABLE SLOTH.

Messerly: THIS IS MO, WHICH IS SHORT FOR "SLOW-MO",

WHO IS OUR TWO-TOED SLOTH HERE AT THE ZOO.

Narrator: MO'S KEEPER, MAURA,

HAS BEEN HANGING OUT WITH HIM FOR FIVE YEARS,

BUT CAN'T HANG LIKE THIS FOR LONG.

I'VE BEEN HANGING IN THIS POSITION LESS THAN A MINUTE,

AND MY ARMS ARE ALREADY GETTING TIRED.

Narrator: BUT MAURA'S FIRST REAL PROBLEM IS HEADRUSH,

AS GRAVITY DRAGS BLOOD TOWARDS HER BRAIN.

SLOTHS DON'T HAVE THAT PROBLEM

BECAUSE MANY HAVE UNIQUE VERTEBRA.

MORE BONES IN THEIR NECK

ALLOWS THEM TO ROTATE THEIR HAPPY HEAD 270 DEGREES.

THIS HEAD ROTATION LETS SLOTHS

COMFORTABLY KEEP THEIR BRAINS LEVEL WITH THEIR HEART

AND THEIR BLOODFLOW STEADY,

WHATEVER POSITION THEY'RE HANGING IN.

SO THAT EXPLAINS WHY NO HEADRUSH,

BUT HOW DO YOU EXPLAIN THE REST OF HIS ORGANS

COMFORTABLY HANGING THIS WAY?

HUMANS CAN'T DO IT.

ALL OF OUR INTERNAL ORGANS WOULD BE OUT OF PLACE,

AND THEY WOULD BE PRESSING ON OUR LUNGS,

WHICH WOULD MAKE IT REALLY HARD TO BREATHE.

Narrator: FOR SLOTHS, MORE BIOLOGICAL BRILLIANCE

MEANS THEY CAN BREATHE EASY.

THEY HAVE SPECIAL FIBROUS MEMBRANES

THAT ANCHOR THE LIVER AND STOMACH TO THE RIBS.

SO, JUST LIKE THE SLOTH FROM THE TREE, THE ORGANS ALSO HANG,

AND THIS KEEPS THE ORGANS FROM CRUSHING THE LUNGS.

BUT HOW DO SLOTHS HOLD ON FOR SO LONG

WITHOUT GETTING EXHAUSTED?

SURPRISINGLY, ALTHOUGH MO'S NOT BUILT LIKE A WEIGHTLIFTER,

HE USES MUSCLE-POWER.

PART OF THE SECRETS TO A SLOTH'S SUCCESS

IS THAT THEY ARE PACKED FULL OF SLOW-TWITCH MUSCLES.

Narrator: SLOW-TWITCH MUSCLES ARE MUSCLE FIBERS

THAT USE SMALL AMOUNTS OF ENERGY AND HAVE INCREDIBLE STAMINA.

MOST ANIMALS HAVE A MIX OF THESE SLOW-TWITCH MUSCLES

FOR ENDURANCE AND FAST-TWITCH MUSCLES FOR BURSTS OF SPEED.

BECAUSE SLOTH MUSCLES ARE NEARLY ALL SLOW-TWITCH,

THEY ARE EXTREMELY SLOW,

BUT CAN HANG AND HANG WITHOUT MUSCLE ACHE.

THEY'RE COMFORTABLE TO SUPPORT THEMSELVES

FOR LONG PERIODS OF TIME AND EVEN SLEEP UPSIDE DOWN.

Narrator: IT'S AN INCREDIBLE HANGING TECHNIQUE

THAT ALLOWS MO AND ALL OTHER SLOTHS

TO HANG OUT ALL DAY, EVERY DAY.

[ FROG CROAKING ]

COMING UP, PREDATORY PELICANS GO HUNTING.

Narrator: BY HUNTING IN A PACK, ANIMALS CAN CATCH MORE FOOD

THAN THEY COULD EVER CATCH ALONE.

WILD DOGS AND KILLER WHALES ARE EXPERTS AT HUNTING TOGETHER,

AND SO ARE PELICANS?

YES. PELICANS ARE ONE OF THE ONLY BIRDS IN NATURE

THAT STALK PREY AS ONE --

BIRDS OF A FEATHER HUNTING TOGETHER.

THERE ARE SEVEN SPECIES OF THE BIG-BILLED PELICAN,

AND THE GREATEST PACK HUNTER IS THE WHITE PELICAN.

THESE GIANTS STAND AT NEARLY 6 FEET TALL,

WITH A 10-FOOT WINGSPAN.

AND IN LAKES ACROSS NORTH AND CENTRAL AMERICA,

THEY FLOCK IN THEIR THOUSANDS.

ONLY BY WORKING AS A PACK CAN THEY ALL SURVIVE.

THE HUNT BEGINS WITH DOZENS OF BIRDS FLOCKING TOGETHER,

AND WHEN THEY FIND A SHOAL OF FISH,

THEY FORM A FEARSOME, FEATHERY WALL IN THE WATER.

BUT IT'S WHAT HAPPENS BENEATH THE WATER

THAT IS PURE PELICAN GENIUS.

THE BIRDS BEAT THEIR WINGS ON THE SURFACE AND KICK UNDER IT,

SCARING FISH THAT SWIM IN THE OPPOSITE DIRECTION TO ESCAPE.

WHAT THE FISH DON'T KNOW IS THE CLEVER PELICANS

ARE HERDING THEM INTO A TRAP.

THE BIRDS PUSH THEIR PREY INTO THE SHALLOWS,

WHERE THE FISH ARE CLOSER TO THE SURFACE,

THEN SURROUND THE FISH,

CORRALLING THEM INTO A SMALLER AND SMALLER SPACE.

AND FINALLY, WHEN THE FISH HAVE NO CHANCE OF ESCAPE,

IT'S DINNERTIME.

WITH THEIR FOOT-LONG, EXPANDABLE, NET-LIKE BILL,

THEY CAN SCOOP UP THREE GALLONS OF WATER AT ONCE,

AND WITH IT, SEVERAL FISH.

IT'S LIKE CATCHING FISH IN A BARREL.

ALL FOR ONE, AND FISH FOR ALL.