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 HUMPBACK WHALES FLY?

WHAT'S BEHIND THE DOGGY HEAD TILT?

AND WHY ON EARTH DO ANIMALS SWARM?

THESE WONDERS AND MORE ON...

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

CAPTIONS PAID FOR BY DISCOVERY COMMUNICATIONS

SOMETIMES, DOGS JUST MELT YOUR HEART --

LIKE WHEN THEY DO THIS...

OR THAT...

OKAY, NOT THAT.

THAT'S MORE LIKE IT -- THE CLASSIC HEAD TILT.

BUT HAVE YOU EVER WONDERED WHAT IT ACTUALLY MEANS?

WHAT ARE THOSE EXPECTANT EYES AND EARS REALLY SAYING?

"WALKIES"?

"FEED ME"?

"I LOVE YOU"?

BUT REALLY...

THERE ARE 90 MILLION DOGS IN THE U.S.,

FROM TINY CHIHUAHUAS TO HUGE MASTIFFS.

FOR MILLENNIA, THESE FAITHFUL FRIENDS

HAVE LISTENED TO US YABBERING ON AT THEM.

AND LOOK WHAT HAPPENS WHEN WE DO.

RESEARCH INDICATES THAT THE HEAD TILT

COULD BE A RESPONSE TO SOUND.

DOGS HAVE VERY SENSITIVE EARS.

THEY CAN EVEN HEAR THIS.

I BET YOU DIDN'T CATCH THAT, DID YOU?

THAT'S BECAUSE DOGS CAN HEAR THINGS

FROM FOUR TIMES FARTHER AWAY THAN WE CAN.

BUT UNLIKE HUMANS, THEIR EARS ARE DIRECTIONAL.

SO, THEY HAVE TO TURN THEIR HEAD TOWARDS THE SOUND.

BUT WHAT HAPPENS WHEN THE SOUND IS RIGHT IN FRONT OF THEM,

LIKE WHEN WE TALK TO THEM?

IT'S BELIEVED THAT DOGS ARE HARD-WIRED

TO TURN THEIR HEADS TOWARDS A SOUND.

SO, EVEN WHEN THE NOISE

IS COMING FROM RIGHT IN FRONT OF THEM,

THEY CAN'T HELP GIVING A LITTLE TILT.

IT COULD EVEN BE A DOG WAY OF LETTING US KNOW

THEY'RE LISTENING,

MUCH LIKE THE WAY WE NOD DURING A CONVERSATION.

BUT NEW RESEARCH REVEALS ANOTHER FASCINATING POSSIBILITY.

ALTHOUGH DOGS DON'T KNOW EXACTLY WHAT WE'RE SAYING,

THEY ARE VERY GOOD AT WORKING OUT HOW WE'RE FEELING.

AND ONE OF THE WAYS THEY DO THAT IS BY LOOKING AT OUR MOUTHS.

SHE'S HAPPY. COOL.

NOW, SHE'S IRRITATED.

OH, DEAR.

IT'S BELIEVED THAT THIS COULD BE CONNECTED TO THE HEAD TILTING.

THINK ABOUT IT.

DOGS WITH BIG MUZZLES,

WHAT THE BIOLOGISTS CALL "DOLICHOCEPHALIC" BREEDS,

HAVE A NOSE THAT OBSTRUCTS THE LOWER HALF OF THEIR VISION.

SO, TO GET AN UNOBSTRUCTED VIEW OF OUR MOUTH,

THE DOG TILTS ITS HEAD.

OH, THAT'S BETTER.

A RECENT SURVEY OF DOG OWNERS SUGGESTS

THAT UP TO 71% OF LONG-MUZZLED BREEDS

TILTED THEIR HEADS WHEN SPOKEN TO,

AS OPPOSED TO JUST 52% OF FLATTER-NOSED BREEDS.

SO, BY TILTING THEIR HEADS, DOGS ARE DOING

WHAT ALL BEST FRIENDS SHOULD DO --

CONCENTRATING ON HOW YOU'RE FEELING.

I'M DOING FINE, THANK YOU.

HOW ARE YOU?

HUMPBACK WHALES ARE MASSIVE.

THE BIGGEST ON RECORD BROKE THE SCALES AT A STAGGERING 99 TONS,

A WHOPPING 10 TIMES HEAVIER THAN A KILLER WHALE,

AND ALMOST DOUBLE THE WEIGHT OF A SPERM WHALE.

BUT DESPITE WEIGHING AS MUCH AS FOUR SCHOOL BUSSES,

HUMPBACKS ARE THE MASTER ACROBATS OF THE OCEAN.

THESE ASTONISHING GIANTS CAN DO THIS...

IN CALIFORNIA'S MONTEREY BAY,

IT'S A SPECIAL DAY FOR HUMPBACK-WHALE EXPERT

NANCY BLACK.

Black: THE HUMPBACK WHALES -- THEY'VE BEEN FEEDING

REALLY CLOSE TO THE BEACH ON BIG,

MASSIVE SCHOOLS OF ANCHOVIES.

Narrator: 5 MILES SOUTH OF THE BAY, A MULTI-MILLION-STRONG SHOAL

OF 7-INCH ANCHOVIES HAS ATTRACTED A HOST OF PREDATORS.

NANCY'S HOPING THE HUMPBACKS WILL SOON BE HERE

TO GET IN ON THE FEAST.

JUST GOT TO THIS AREA.

IT LOOKS REALLY INTERESTING,

BECAUSE THERE'S ABOUT 200 SEA LIONS,

AND THERE'S ALL THESE BIRDS DIVING DOWN,

THERE'S PELICANS PLUNGE-DIVING.

A LOCAL WHALE-WATCHING BOAT IS ALSO HOPING TO CATCH

ONE OF NATURE'S MOST AMAZING SPECTACLES.

[ CROWD MURMURING ]

OH, BIG LUNGE RIGHT THERE.

Narrator: A GROUP OF HUMPBACKS, SOME WEIGHING AROUND 50 TONS,

LEAPING UP TO THREE STORIES INTO THE AIR.

IN ORDER TO ACHIEVE THIS ASTONISHING FEAT,

THESE GOLIATHS MUST BREAK THE SURFACE

AT MORE THAN 18 MILES AN HOUR.

FOR THIS BULK TO REACH THAT SPEED,

SCIENTISTS WERE PRETTY SURE

THE WHALES WOULD NEED A LONG RUN-UP.

BUT NANCY HAS SEEN SOMETHING NO ONE COULD HAVE EXPECTED.

Black: MOST PEOPLE THOUGHT THAT, YOU KNOW, WHALES HAVE TO DIVE

MAYBE A HUNDRED FEET BEFORE THEY, YOU KNOW, COME UP.

BUT IT'S LIKE, NO, THEY DON'T EVEN NEED TO GO DOWN THAT DEEP.

MAYBE 20 FEET.

Narrator: FROM JUST 20 FEET DOWN,

THE HUMPBACK ACHIEVES INCREDIBLE ACCELERATION.

PUMP, PUMP, PUMP, AND THEN UP.

Narrator: SO, HOW DO THEY DO IT?

THE SECRET IS A HUGE, 15-FOOT-LONG MUSCLE

CALLED A "PEDUNCLE"

THAT STRETCHES ALONG THE HUMPBACK'S TAIL.

WEIGHING MORE THAN A HORSE,

THE PEDUNCLE IS THE STRONGEST MUSCLE IN THE ANIMAL KINGDOM.

IT CAN GENERATE AS MUCH THRUST AS A 747 DURING TAKEOFF.

[ CROWD CHEERING ]

AND THE WHALE HAS ANOTHER SECRET BEHIND ITS SPEED.

JUST BEFORE TAKEOFF, IT FLAPS ITS FLIPPERS LIKE A BIRD.

AND THESE ARE NO ORDINARY FLIPPERS.

EACH ONE IS 15 FEET LONG, AND BUMPY ON THE EDGES,

LIKE A TWO-SIDED SERRATED KNIFE.

SCIENTISTS NOW KNOW THESE BUMPS REDUCE WATER TURBULENCE

TO GIVE EXTRA LIFT AND POWER.

IN FACT, THE BUMPS ARE ATTRACTING

THE ATTENTION OF FLIGHT ENGINEERS.

THE EFFICIENCY OF A HUMPBACK'S FLIPPERS

COULD HELP AIRPLANE WINGS PROVIDE MORE LIFT AND LESS DRAG.

WHILE SCIENTISTS THINK THEY KNOW THE MECHANICS OF THE LEAP,

NO ONE IS REALLY SURE WHY THE WHALES DO IT.

BUT NANCY THINKS IT'S GOT SOMETHING TO DO

WITH HOW THEY FEED.

LOOK AT THIS -- A SYNCHRONIZED ATTACK ON A SHOAL OF FISH.

SOMEHOW, THEY'VE LEARNED TO, YOU KNOW, COORDINATE THIS BEHAVIOR.

Narrator: TO WORK TOGETHER IN AN ATTACK,

THEY NEED TO TELL EACH OTHER WHERE THEY ARE.

IT'S THOUGHT THEY DO THIS

BY SLAPPING THE SURFACE OF THE WATER.

BUT WHEN THEY'RE FAR APART, OR WHEN THE SEA IS ROUGH,

NANCY BELIEVES THEY NEED SOMETHING LOUDER.

Black: SOMETIMES, I'VE NOTICED, THEY BREACH MORE WHEN IT'S WINDY OUT.

THAT COULD BE, YOU KNOW, THE SOUNDS THAT THE BREACH

IS MAKING IS COMMUNICATION ABOVE THE WAVES.

Narrator: IF NANCY'S RIGHT, THEN THIS COULD BE PROOF

THAT THE INTELLIGENCE OF THESE CREATURES

FAR EXCEEDS ANYTHING THAT WE'VE PREVIOUSLY THOUGHT POSSIBLE.

NANCY'S EVEN PICKED UP ON ANOTHER INDICATION

OF THEIR SMARTS -- A SENSE OF HUMOR.

SOMETIMES, IT SEEMS LIKE THEY'RE DOING IT AS A SHOW-OFF TO US,

BECAUSE THEY'RE REALLY COMING OVER TO THE BOAT, BREACHING...

...AND THEN, YOU KNOW, SWIM AWAY.

Narrator: SO, OCCASIONALLY, MAYBE THEIR BIG SPLASH

IS JUST THE HUMPBACKS HAVING A WHALE OF A TIME.

COMING UP...

A TARANTULA'S OUT-OF-BODY EXPERIENCE,

THE WORD'S COOLEST SWARMS, AND THE SECRET BEHIND HIPPOS' SWEAT.

Narrator: EVERY SO OFTEN, ALL SPIDERS DO SOMETHING

BOTH WEIRD AND EXTRAORDINARY.

OH, NO. THERE SHE GOES AGAIN.

THEY CLIMB OUT OF THEIR OWN BODY.

IT'S AN INCREDIBLE TRANSFORMATION.

BUT...

SPIDERS EAT 600 MILLION TONS OF INSECTS A YEAR.

WITHOUT THEM, WE'D BE OVERRUN BY CREEPY-CRAWLIES.

SO, ALTHOUGH THIS CHAP LOOKS FEARSOME,

HE'S REALLY OUR FRIEND.

TARANTULAS LIKE THIS WILL NEVER ATTACK A HUMAN,

BUT MAY SHOW THEIR FANGS WHEN CORNERED.

AND IN THE UNLIKELY EVENT THAT HE DOES BITE,

IT'S NO WORSE THAN A WASP'S STING.

THE TRUTH IS, TARANTULAS ARE PRETTY DOCILE,

WHICH IS WHY THOUSANDS OF PEOPLE KEEP THEM AS PETS.

SO, IT'S NOT SURPRISING OWNERS GET UPSET

WHEN ITSY-BITSY TAKES A TURN FOR THE WORSE AND ROLLS OVER.

ARACHNID EXPERT KELLI WALKER FROM CINCINNATI ZOO

HAS SEEN THIS BEHAVIOR MANY TIMES.

IT'S NOT DEAD.

THAT'S ACTUALLY A COMMON THING THAT PEOPLE THINK

WHEN THEY SEE A SPIDER ROLLING OVER ONTO ITS BACK.

Narrator: THE CAUSE IS A PROBLEM ITSY HAS WITH HER SKIN.

EVEN THOUGH HER INSIDES ARE GROWING,

HER HARD, OUTER SHELL ISN'T.

IT'S MADE OF CHITIN,

THE SAME STUFF THAT GOES INTO INSECTS' WINGS.

THIS REMARKABLE LIGHTWEIGHT MATERIAL

PROVIDES ESSENTIAL PROTECTION,

BUT JUST LIKE A SUIT OF ARMOR, IT WON'T STRETCH.

SO, IN ORDER FOR HER AND OTHER TARANTULA SPECIES TO GET BIGGER,

THEY ACTUALLY HAVE TO SHED THAT OUTER LAYER, THAT EXOSKELETON,

WHICH CAN BE A VERY STRENUOUS PROCESS FOR THEM.

ROUGHLY ONCE A YEAR,

AND EVEN MORE FOR FAST-GROWING YOUNGSTERS,

OUR HAIRY, EIGHT-LEGGED FRIEND HAS TO PUT HER LIFE ON THE LINE

AND CLIMB OUT OF HER OWN SKIN.

WHILE ON HER BACK, SHE'S A SITTING TARGET

FOR HER MANY PREDATORS.

TIME IS OF THE ESSENCE.

FIRST, A GOOEY LAYER OF SECRETION

STARTS TO SEPARATE THE OLD, OUTER SKIN

FROM ITS NEW SKIN UNDERNEATH.

THEN, THE SPIDER CLENCHES ITS ABDOMEN,

FORCING THE GOOEY LIQUID FROM HER TAIL TO HER HEAD.

THE MORE THE SPIDER CLENCHES, THE MORE THE PRESSURE BUILDS,

UNTIL THE CHITIN ARMOR CRACKS AT THE BACK OF HER HEAD.

NOW, ITSY HAS TO CLIMB OUT OF HER HARD SHELL.

MANY TARANTULAS GET STUCK AT THIS POINT,

AND END UP BEING EATEN OR STARVING TO DEATH.

COME ON, GIRL.

YOU CAN DO IT.

IT TAKES UP TO 12 HOURS FOR THIS PLUCKY ARACHNID TO BREAK FREE.

BUT SHE'S STILL IN GREAT DANGER.

THE SHINY, NEW EXOSKELETON WHICH COVERS HER ENTIRE BODY

IS AS SOFT AS PUTTY,

AND HER NEW CHITIN FANGS

ARE TOO FLIMSY TO PUNCTURE FLESH.

YOU CAN ACTUALLY SEE, AFTER THEY MOLT,

THAT THEIR FANGS ARE STILL WHITE,

WHICH MEANS THEY HAVEN'T HARDENED YET.

SO, THEY'RE ACTUALLY UNABLE TO EAT.

IT WILL TAKE A WEEK FOR THE SKIN AND FANGS TO HARDEN.

ONLY THEN WILL OUR GORGEOUS ARACHNID BE BACK IN THE GAME,

BUSY SAVING US FROM BUG ARMAGEDDON.

AND LOOK, SHE'S LEFT A BEAUTIFUL PRESENT.

MIGHT JUST POP THAT UNDER ONE OF THE KIDS' PILLOWS,

SEE HOW THEY LIKE IT.

COMING UP...

THE REAL STORY BEHIND NATURE'S SWARMS

AND A HIPPO'S STRANGE SWEAT.

Narrator: ACROSS THE WORLD, ANIMALS ARE GANGING UP IN THE MILLIONS,

BILLIONS, AND EVEN TRILLIONS.

THESE COLOSSAL SWARMS TRULY ARE ONE OF NATURE'S WONDERS.

SWARMS TEND TO GET A BAD PRESS.

BUT YOU KNOW WHAT?

THEY CAN BE BEAUTIFUL.

WE'RE IN MEXICO,

AND THESE MAJESTIC CREATURES ARE MONARCH BUTTERFLIES.

MILLIONS UPON MILLIONS OF MONARCHS

GATHER FOR THE LONGEST MIGRATION OF ANY INSECT ON THE PLANET.

WITH WINTER COMING, THEY UNDERTAKE

AN EPIC 3,000-MILE LONG HAUL, FROM THE U.S.

TO THE RELATIVE WARMTH OF MEXICO.

ALONG THE WAY, THEY ROOST TOGETHER TO RETAIN HEAT.

AH.

WHILE BUTTERFLIES SWARM FOR WARMTH,

OTHERS SWARM FOR LOVE.

IMAGINE THE SCENE -- A BEAUTIFUL TROPICAL ISLAND,

A ROMANTIC BEACH, AND 45 MILLION RED CRABS.

THESE FOREST-DWELLING TREE CRABS ON CHRISTMAS ISLAND

ARE ON AN AMOROUS DASH TO THE SEA.

HERE, BENEATH THE SILVER LIGHT OF THE LAST QUARTER OF THE MOON,

THE MOMMY AND DADDY CRABS GIVE EACH OTHER A WISTFUL LOOK BEFORE

FERTILIZING BILLIONS OF EGGS AND SHAKING THEM OUT INTO THE WATER.

YET, INCREDIBLY, THIS IS NOT THE BIGGEST SWARM OF CRUSTACEANS.

THAT HAPPENS ONE MONTH LATER,

WHEN THE SHORELINE IS COVERED IN A RED CARPET OF TINY CRABS.

A BILLION OR SO BABIES HAVE COME HOME TO JOIN

MOM AND DAD BACK IN THE FOREST.

LET'S HOPE THEY'VE PAINTED THE NURSERY.

BUT ONE ANIMAL REALLY HAS TAKEN SWARMING TO THE NEXT LEVEL.

ACROSS THE ARID DESERTS OF AFRICA AND INDIA,

FARMERS ARE PRAYING FOR RAIN.

BUT IF TOO MUCH FALLS,

IT CREATES THE PERFECT CONDITIONS

FOR A PLAGUE OF LOCUSTS.

LOCUSTS ARE JUST GRASSHOPPERS, BUT WITH SUPERPOWERS.

WHEN FOOD BECOMES ABUNDANT, SO DO THEY.

THEY CHANGE FROM GREEN TO BROWN, BECOME MORE MUSCULAR, MATE MORE,

AND EAT MORE -- MUCH MORE.

EACH LOCUST EATS ITS OWN WEIGHT IN PLANTS EVERY DAY.

WHEN THEIR NUMBERS REACH BIBLICAL PROPORTIONS,

THE DEVASTATION IS BREATHTAKING.

IN THE U.S. IN 1875,

AN ESTIMATED 3 TRILLION ROCKY MOUNTAIN LOCUSTS

SWARMED OVER THE MIDWEST,

COVERING AN AREA TWICE THE SIZE OF COLORADO.

IF IT HAPPENED AGAIN TODAY, THE CONSEQUENCES

FOR THE NATION'S BREADBASKET WOULD BE UNIMAGINABLE.

BUT LUCKILY, NO ONE HAS SEEN A ROCKY MOUNTAIN LOCUST

IN OVER 100 YEARS,

SO THEY'RE THOUGHT TO BE EXTINCT.

PHEW.

COMING UP...

DO HIPPOS REALLY SWEAT BLOOD?

HIPPOS ARE ONE OF THOSE CREATURES

YOU SHOULD NEVER INVITE OVER FOR DINNER.

THEY'RE NOT AT ALL FRIENDLY, THEY'VE GOT BAD BREATH,

AND THEIR STICKY, RED SWEAT MAKES PERSPIRATION LOOK TAME.

WHAT IS THIS STUFF?

IN AFRICA, WILD HIPPOS LIVE IN HERDS

OF AROUND 20, CALLED "BLOATS."

BEING THE SECOND-LARGEST LAND ANIMAL IN THE WORLD,

THEY DON'T HAVE TO WORRY ABOUT PREDATORS,

BUT THEY DO HAVE TO WORRY ABOUT THE SUN.

LIVING NEAR THE EQUATOR, A HIPPO IS AT REAL RISK OF SUNBURN.

SO, WHAT'S A HIPPO TO DO?

THE ANSWER LIES IN THE HIPPO'S RED, OOZY SWEAT.

IT LOOKS LIKE BLOOD, BUT THE RED OOZE IS ACTUALLY FLUID

LOADED WITH A SPECIAL RED MOLECULE

CALLED "HIPPOSUDORIC ACID,"

WHICH ABSORBS THE SUN'S HARMFUL U.V. RAYS.

THE HIPPOSUDORIC ACID IS SUSPENDED IN AN OILY GLOOP

WHICH SPREADS ACROSS THE HIPPO'S SKIN.

SO, THIS HIPPO SWEAT IS NOT BLOOD AT ALL.

IT'S A RED, WATER-RESISTANT SUNSCREEN.

AND LIBERAL USE OF SUNSCREEN IS THE BEST WAY TO STAY PRETTY.

THE RED GLOOP ALSO COMES IN VERY HANDY WHEN THIS HAPPENS.

TWO BIG MALES ARE FIGHTING.

THE WINNER WILL BE ABLE TO MATE WITH THE FEMALES IN THE BLOAT.

20-INCH-LONG CANINES AS SHARP AS KNIVES CAUSE NASTY,

DEEP FLESH WOUNDS.

THE REIGNING KING HAS SUCCESSFULLY DEFENDED HIS CROWN,

AND THE RIVAL RETREATS, NURSING HIS INJURIES.

LUCKILY FOR THE LOSER, THE AMAZING STICKY RED SUNBLOCK

CONTAINS AN ANTIBACTERIAL THAT FIGHTS INFECTIONS

AND HELPS TO HEAL HIS WOUNDS.

SO, THANKS TO THE GLOOP,

NOT ONLY CAN HE GET ON WITH HEALING,

HIPPOS CAN GET BACK TO THEIR SUN-WORSHIPPING

WITHOUT RISK OF PEELING.

MARVELOUS.