Original subtitles

HIGH ON A COLORADO RIDGE LIE A SET OF SCRATCH MARKS

ENCASED IN ROCK FOR 100 MILLION YEARS.

ARE THEY UNPRECEDENTED EVIDENCE OF A VIOLENT DINOSAUR CLASH?

A NEW 3-D ANALYSIS COULD REWRITE OUR UNDERSTANDING

OF DINO BEHAVIOR.

I MEAN, THIS IS BIG, RIGHT?

I MEAN, THIS IS SOMETHING REALLY NEW.

AND BENEATH THE HIGHLY TOXIC WATERS OF A CALIFORNIA LAKE,

A STRANGE BACTERIA IS THRIVING AGAINST ALL ODDS...

LEADING SOME TO BELIEVE IT COULD BE FROM ANOTHER PLANET.

HOLY SMOKES! LOOK AT THIS ONE.

I'LL DEPLOY CUTTING-EDGE TECH TO SCAN THE LAKE BED

FOR EVIDENCE OF AN ALIEN INVASION.

WELL, THAT'S NOT WHAT WE WERE EXPECTING, WAS IT?

HIDDEN JUST BELOW THE EARTH'S SURFACE,

THERE ARE COUNTLESS UNSOLVED MYSTERIES.

AND, TODAY, WE FINALLY HAVE THE TOOLS TO UNLOCK THEM.

LOOK AT THAT!WHOA.

I THINK THIS IS IT.

I'M ROB NELSON,

A SCIENTIST USING STATE-OF-THE-ART TECHNOLOGY

TO PEEL THE LID OFF OUR PLANET'S HIDDEN DEPTHS.

THE MOMENT OF TRUTH RIGHT HERE.

HOLY MOLY!

THESE ARE THE SECRETS OF THE UNDERGROUND.

Captions by VITAC-- www.vitac.com

CAPTIONS PAID FOR BY DISCOVERY COMMUNICATIONS

LESS THAN 15 MILES WEST OF DOWNTOWN DENVER,

IN THE SHADOW OF THE ROCKY MOUNTAIN FOOTHILLS

SITS ONE OF THE MOST SIGNIFICANT FOSSIL SITES IN THE WORLD.

SEEN FROM ABOVE, IT'S LIKE A JAGGED SPINE

RISING FROM SOFTLY UNDULATING LAND.

LOOK CLOSER AND YOU CAN SEE

HOW THIS FORMATION EARNED THE NAME "DINOSAUR RIDGE."

ON ONE SIDE, QUARRIES,

WHERE SOME OF THE MOST ICONIC BEASTS OF THE JURASSIC AGE

WERE FIRST UNEARTHED IN THE 1870s,

SETTING OFF A WHIRLWIND OF DINOSAUR FINDS

THAT CONTINUES TO THIS DAY.

ON THE OTHER SIDE, A STEEP ROCK FACE

COVERED IN MORE THAN 300 FOSSILIZED DINO TRACKS

WHICH LAY CONCEALED BENEATH COUNTLESS LAYERS OF STONE,

UNTIL BLASTING FOR A NEW ROAD ACCIDENTALLY EXPOSED THEM.

AND RECENTLY, NOT FAR FROM THIS FIELD OF FOOTPRINTS,

SCIENTISTS HAVE MADE YET ANOTHER JAW-DROPPING DISCOVERY--

LONG, VIOLENT GOUGES IN THE ROCK,

POSSIBLY MADE BY DINOSAURS.

COULD THIS BE THE SCENE OF A BLOODY CLASH

BETWEEN TWO MIGHTY BEASTS--

A JURASSIC SNAPSHOT PRESERVED FOR MILLENNIA?

IF SO, IT IS TRULY ONE OF A KIND

AND COULD BE ONE OF THE MOST SIGNIFICANT DISCOVERIES

IN PALEONTOLOGY IN THE LAST 50 YEARS.

MOST DINOSAUR FINDS SIMPLY CAN'T TELL US

HOW THESE LONG EXTINCT ANIMALS BEHAVED WHILE ROAMING THE EARTH.

BUT WHEN I LOOK AT PICTURES OF THESE MARKINGS,

ALL I SEE IS BUMPY ROCK,

WHICH SEEMS LIKE IT COULD BE ALMOST ANYTHING-- LIKE EROSION.

SO I'M NOT QUITE CONVINCED THEY WERE MADE BY A DINOSAUR.

TO GET A CLEARER VIEW,

I NEED TO SEE THESE SUPPOSED SCRATCH MARKS FOR MYSELF.

I WANT TO DEPLOY SOME HI-TECH GEAR

TO ANALYZE THE GOUGES.

SO I'M MEETING UP WITH DR. MARTIN LOCKLEY,

WHO DISCOVERED THEM.

DR. LOCKLEY!

I CATCH UP WITH HIM ON THE ROCK FACE

COVERED IN DINO PRINTS.

THIS IS AWESOME!

SO THIS IS WHERE DINOSAURS WALKED, RIGHT HERE?

YEAH, HAVE YOU EVER SEEN

SO MANY TRACKS IN ONE PLACE?

INCREDIBLE.

SOME PALEONTOLOGISTS SUSPECT MANY OF THESE PRINTS

MAY HAVE BEEN LEFT BY THE SAME DINOSAUR SPECIES

WHO LEFT THE SCRATCH MARKS.

WELL, THERE'S TWO MAIN TYPES OF FOOTPRINTS HERE.

YOU CAN SEE THIS ONE HERE--

IT'S VERY BIRD LIKE.

THEN WE HAVE THESE TYPES OF FOOTPRINTS

WHICH ARE MORE CHUNKY OR FLESHY,

AND THEY'RE MADE BY AN IGUANODON-TYPE OF DINOSAUR,

A BIG HERBIVORE.

SCIENTISTS HAVE ALREADY DATED THESE FOSSILIZED TRACKS

TO ABOUT 100 MILLION YEARS AGO.

HOW ARE THERE STILL FOOTPRINTS OF DINOSAURS?

I MEAN, IT FEELS LIKE THEY WOULD'VE WASHED AWAY.

I DON'T UNDERSTAND.

YOU'RE PROBABLY RIGHT THAT 90% OF ALL TRACKS

THAT WERE MADE DID WASH AWAY,

BUT IF YOU HAVE JUST THE RIGHT CONSISTENCY

OF THE SUBSTRATE-- THE SAND OR THE MUD--

THAT WOULD TAKE A VERY NICE IMPRESSION

AND IT COULD ALSO DRY OUT,

SO IT BECOMES MORE LIKE CEMENT.

THIS AREA OF COLORADO WAS ONCE A COASTAL PLAIN,

MUCH LIKE THE LANDS BORDERING THE GULF OF MEXICO TODAY.

WHAT IS NOW STEEP ROCK WAS, BACK THEN,

A FLAT, WET, BEACH-LIKE ENVIRONMENT.

PROBABLY A LOT OF FOOTPRINTS

WERE MADE ON THIS SURFACE AND SMUDGED OUT,

AND WHAT WE'RE SEEING IS THE LAST CLEAR ONES

BEFORE THIS LAYER WAS COVERED OVER

WITH ANOTHER LAYER OF SEDIMENT.

IT WASN'T UNTIL 1937

THAT THE NOW-FOSSILIZED FOOTPRINTS

WERE EXPOSED ONCE MORE--

UNCOVERED AS WORK CREWS WERE CLEARING AWAY ROCK

TO CREATE THE NEARBY WEST ALAMEDA PARKWAY.

THAT DISCOVERY OPENED UP A WHOLE NEW WAY OF LOOKING AT DINOSAURS,

BECAUSE IT WAS ONE OF THE FIRST SETS OF FOSSILS

EVER DISCOVERED THAT PROVIDED INSIGHT INTO HOW THEY LIVED,

INSTEAD OF HOW THEY DIED.

HOW ARE STUDYING BONES DIFFERENT THAN STUDYING THESE?

PEOPLE WHO STUDY BONES

REALLY ARE STUDYING DEATH AND DESTRUCTION.

IF THE SKELETON'S COMPLETE, THEY'RE STUDYING

HOW THE DEAD ANIMAL WAS BURIED QUICKLY.

BUT IF THE SKELETON'S ALL BROKEN UP, THEY'RE STUDYING

HOW IT DECAYED OR HOW IT WAS TORN APART.

BUT WITH TRACKS, WE'RE ALWAYS STUDYING

THE DYNAMIC, LIVING ANIMAL

AS IT WAS WALKING AROUND ON A PARTICULAR DAY

100 MILLION YEARS AGO.

WAS IT SOLITARY?

DID IT HAVE OTHER SIMILAR ANIMALS

GOING IN THE SAME DIRECTION WITH IT?

THESE FOOTPRINTS HELP ANSWER HOW THE DINOSAURS MOVED,

BUT THE SCRATCH MARKS COULD REVEAL SOMETHING

EVEN MORE EXCITING...

LIKE HOW THEY FOUGHT...

THAT IS, IF THEY'RE ACTUALLY DINOSAUR SCRAPES.

I STILL HAVE TO SEE THEM FOR MYSELF.

WELL, HERE WE ARE AT THE NEXT DINOSAUR TRACK SITE.

I HEAD WITH DR. LOCKLEY TO A SITE

JUST OFF A TWO-LANE ROAD NOT FAR FROM THE FOOTPRINTS.

YOU HAVE TO GET YOUR EYE IN, KIND OF,

TO SEE WHAT'S HERE.

CAN YOU SEE THE WAY

THAT THERE'S TWO BIG, LONG GROOVES?

THE MARKINGS ARE EXTREMELY LARGE,

BUT DOES THAT AUTOMATICALLY MEAN THEY WERE MADE BY DINOSAURS?

SO, THESE ARE SCRATCH MARKS?

LET ME POINT OUT THAT THERE'S A RIDGE DOWN THE MIDDLE.

SO, I ASK YOU,

DO WE HAVE MAYBE A LEFT SIDE AND A RIGHT SIDE HERE?

I SUPPOSE IT'S POSSIBLE THEY'RE GASHES LEFT BY ANCIENT ANIMALS,

BUT TO MY EYES, THEY COULD JUST AS EASILY

HAVE BEEN GOUGED OUT BY A MODERN BULLDOZER.

SO, BEFORE I GO ANY FURTHER,

I NEED TO FIND OUT IF THESE MARKS ACTUALLY DATE

TO THE SAME TIME PERIOD AS THE FOOTPRINTS.

FIRST OF ALL,

HOW DO WE KNOW WHEN THESE MARKS WERE MADE?

DR. LOCKLEY EXPLAINS

THAT PALEONTOLOGISTS PRIMARILY DATE

FOSSILIZED MARKINGS, LIKE THE SCRATCHES,

BY DETERMINING THE AGE OF THE ROCK

ON WHICH THE IMPRESSION IS LEFT.

THAT'S OFTEN DONE WITH A PROCESS

CALLED RADIOMETRIC DATING.

IT'S A METHOD THAT RELIES ON ELEMENTS FOUND IN THE ROCK.

OVER TIME, EACH ELEMENT WILL SHED NEUTRONS

AND DECAY AT A KNOWN RATE THAT SCIENTISTS CAN MEASURE

TO GET AN APPROXIMATE DATE FOR THE ROCK'S SURFACE,

BUT THE KEY ELEMENTS FOUND IN SEDIMENTARY ROCK,

WHERE FOSSILS ARE USUALLY DISCOVERED,

DECAY TOO RAPIDLY TO BE A RELIABLE DATING SOURCE

FOR SUCH OLD SURFACES.

HOWEVER, THERE ARE ELEMENTS THAT EXIST

IN VOLCANIC ASH, LIKE URANIUM AND POTASSIUM,

WHICH DECAY MORE SLOWLY.

SO GEOLOGISTS WILL LOOK FOR LAYERS OF ASH

ABOVE AND BELOW THE ROCK IN WHICH THE FOSSILS ARE FOUND.

BY DATING EACH LAYER OF ASH,

THEY CAN DETERMINE AN AGE RANGE FOR THE ROCK

AND THE FOSSILS IN QUESTION.

WE KNOW THAT THIS ROCK FORMATION

HAS SOME VOLCANIC ASH LAYERS IN IT.

IN FACT, THEY'RE JUST UP HERE.

I CAN SHOW YOU.

SURE ENOUGH, THERE'S A CREAM-COLORED STRIP

OF HARDENED VOLCANIC ASH

STILL VISIBLE JUST BELOW THE SCRATCH MARKS.

HERE IS THE VOLCANIC ASH.

THERE'S A LITTLE PIECE OF IT THERE.

GEOLOGISTS HAVE ANALYZED THIS QUITE A FEW TIMES

AND CONSISTENTLY COME UP WITH AGES

THAT ARE JUST A LITTLE BIT OVER 100 MILLION YEARS.

THIS MEANS THAT THE ROCK ON WHICH THESE MARKS WERE LEFT

IS ALSO ABOUT 100 MILLION YEARS OLD,

JUST LIKE THE ROCK COVERED IN DINOSAUR FOOTPRINTS.

SO, THE TIMELINE SEEMS TO FIT.

BUT JUST BECAUSE THE ROCK IS 100 MILLION YEARS OLD

DOESN'T NECESSARILY MEAN THE SCRATCHES ARE.

LET'S FACE IT-- A LOT HAS HAPPENED SINCE THEN,

AND ANY NUMBER OF CULPRITS COULD BE BEHIND THESE MARKINGS--

LATER ANIMALS, EARLY HUMANS, OR EVEN THE EARTH ITSELF.

SO I NEED TO DIG DEEPER FOR NEW CLUES

ABOUT WHAT, OR WHO, MADE THEM.

WHEN YOU'RE READY.

FIRE.

AND LATER, I'LL INVESTIGATE CLAIMS

THAT A CALIFORNIA LAKE IS INFESTED WITH ALIENS.

THIS AREA REALLY IS BIZARRE.

IS THIS THE FIRST EVIDENCE OF EXTRATERRESTRIAL LIFE,

RIGHT HERE IN CALIFORNIA?

COULD THIS LAKE HAVE BEEN FORMED BY A METEOR?

I'M AT DINOSAUR RIDGE, JUST OUTSIDE DENVER,

TO SEE WHAT COULD BE DINOSAUR SCRATCH MARKS,

EXPOSED IN MODERN TIMES

AFTER BEING BURIED BENEATH LAYERS OF ROCK FOR MILLENNIA.

IF THESE GOUGES WERE MADE BY A DINOSAUR,

IT COULD BE UNPRECEDENTED EVIDENCE OF A VIOLENT ENCOUNTER.

I WANT TO BRING IN SOME HI-TECH TOOLS

TO EVALUATE THE SCRATCHES, BECAUSE I'M NOT YET CONVINCED

THEY WERE ACTUALLY MADE BY A DINOSAUR,

AND I HAVE EVERY REASON TO BE SKEPTICAL,

GIVEN THE LONG HISTORY OF EXAGGERATIONS, HALF-TRUTHS,

AND FULL-ON FABRICATIONS ABOUT DINOSAUR REMAINS.

IN THE LATE 1800s,

TWO EARLY PALEONTOLOGISTS NAMED O.C. MARSH AND EDWARD COPE

WERE LOCKED IN A FIERCE RIVALRY DUBBED "THE BONE WARS."

THEY WERE EACH RACING TO UNEARTH FOSSILS

AND NAME NEW DINOSAURS.

SO, IN THE HEAT OF COMPETITION,

MARSH ANNOUNCED ONE OF HIS FINDS WAS AN ENTIRELY NEW SPECIES

WHEN IT WAS REALLY JUST A MORE INTACT SPECIMEN

OF ONE ALREADY KNOWN.

FAST-FORWARD TO 1999

WHEN A NEVER-BEFORE-SEEN FEATHERED FOSSIL

WAS SUPPOSEDLY FOUND IN CHINA.

IT WAS LAUDED AS A TRUE MISSING LINK

BETWEEN DINOSAURS AND BIRDS,

BUT WHEN CONDUCTING A DETAILED CT SCAN,

SCIENTISTS DISCOVERED IT WAS MADE UP OF 88 DIFFERENT PIECES

TAKEN FROM MULTIPLE FOSSILS.

SO, WITH FOSSIL FAKERY SO RAMPANT,

ISN'T IT ALSO POSSIBLE THAT THESE SCRATCHES WERE MADE

BY SOME MODERN PRANKSTER SEEKING NOTORIETY?

AND EVEN IF NOT,

CAN WE REALLY RULE OUT OTHER FORCES LIKE EROSION,

OR A MORE RECENT ANIMAL, LIKE A MOUNTAIN LION?

I THINK FOR ME TO SAY IT'S DEFINITELY SCRATCH MARKS,

I'M GONNA HAVE TO LOOK AT A LITTLE BIT MORE DATA.

LUCKILY, THERE'S AN EASY WAY TO TEST ALL THESE THEORIES.

IF THESE MARKINGS WERE MADE MORE RECENTLY,

SAY, BY A HUMAN, A MACHINE, OR EVEN EROSION,

THEY WOULD LIKELY BE LIGHTER IN COLOR.

THAT'S BECAUSE MOST ROCK HAS WHAT GEOLOGISTS CALL PATINA,

AN ANCIENT WEATHERED LAYER THAT ENCRUSTS ITS SURFACE.

ONCE THAT PATINA IS REMOVED,

THE ROCK UNDERNEATH APPEARS TO BE A DIFFERENT SHADE.

BUT THAT DOESN'T SEEM TO BE THE CASE HERE.

THE SURFACE OF THE MARKS APPEARS TO BE

RELATIVELY UNIFORM IN COLOR,

MATCHING THE SHADING

OF THE 100-MILLION-YEAR-OLD ROCK AROUND THEM.

SO, IT SEEMS MUCH MORE LIKELY THAT THESE SCRATCHES WERE MADE

WHEN DINOSAURS ROAMED THIS AREA.

BUT WHY?

WHAT EXACTLY WENT ON HERE 100 MILLION YEARS AGO?

TO FIGURE THAT OUT,

I NEED A MORE PRECISE VIEW OF THESE MARKINGS,

A DETAILED CLOSE-UP

ONLY POSSIBLE WITH THE AID OF CUTTING-EDGE TECHNOLOGY.

HEY, GUYS!Breithaupt: HI.

SO, I'M BRINGING IN TWO EXPERTS

IN THE FIELD OF 3-D PHOTOGRAMMETRY--

NEFFRA MATTHEWS AND BRENT BREITHAUPT.

PHOTOGRAMMETRY WEAVES TOGETHER

MULTIPLE 2-D IMAGES TO CREATE A 3-D MODEL

WITH PRECISE TOPOGRAPHICAL DETAILS.

THIS IS GOING TO BE LIKE FORENSIC PALEONTOLOGY.

WE MIGHT BE ABLE TO SEE SOME THINGS

ON OUR COLOR DEPTH MAPS AND OUR OTHER HIGH-RESOLUTION IMAGERY

THAT WE DON'T SEE THAT EASILY WITH OUR NAKED EYE.

I'VE USED THIS TECHNIQUE BEFORE TO CREATE DIGITAL MODELS

OF AN UNDERWATER ROCK IN LAKE MICHIGAN.

THERE YOU GO. THANK YOU.

NOW I'M HOPING THIS PROCESS WILL HELP DETERMINE

IF THESE SCRATCH MARKS ARE THE REAL DEAL.

ALL RIGHT, LET'S DO IT.

THE PRECISION OF THE DATA SHOULD LET ME GET A BETTER READ

ON THE MEASUREMENTS OF THE MARKINGS.

AND IF MULTIPLE GROOVES ARE ABOUT THE SAME SIZE,

THAT WOULD STRONGLY SUGGEST

THEY ARE NOT RANDOM OR ACCIDENTAL.

THESE ARE YOUR CALIBRATORS.

TO ENSURE TOTAL ACCURACY,

WE PLACE SCALE BARS AROUND THE MARKINGS.

THESE ARE SPECIALLY CALIBRATED TO MEASURE

TO THE SUB-MILLIMETER LEVEL.

YOU WANT A PLACE SO THEY DON'T MOVE.

ONCE THEY'RE SET,

THEY CAN'T MOVE THROUGHOUT THE PROCESS HERE.

WITH THE BARS IN PLACE, WE START SNAPPING AWAY.

MAKE SURE I HAVE A PRETTY GOOD STABLE GROUND.

YOU'RE GOOD. WHEN YOU'RE READY.

OKAY. HIGHER?

NOW TRY TO TAKE A STEP OVER.

TILT IT BACK A LITTLE BIT NOW.

OKAY, THERE YOU GO.

FIRE.

FIRE.

ONE MORE.

FIRE.

PERFECT. DID THAT LOOK GOOD, NEFFRA?

THAT LOOKS GREAT.

WITH THE WIND PICKING UP ON THE RIDGE,

IT'S TIME TO DOWNLOAD THE IMAGES.

SPECIAL SOFTWARE WILL KNIT THE 2-D PHOTOS TOGETHER

TO CREATE A DETAILED 3-D RENDERING.

REALLY EXCITED TO SEE WHAT THIS DATA REVEALS.

COULD WE BE ON THE VERGE OF A DISCOVERY

THAT WILL FOREVER CHANGE HOW WE THINK ABOUT DINOSAURS?

OH, MY GOODNESS! LOOK AT THAT!

I'M AT DINOSAUR RIDGE IN COLORADO

TRYING TO GET TO THE BOTTOM OF SOME MYSTERIOUS MARKINGS

THAT MAY PRESERVE THE VIOLENT BEHAVIOR OF A DINOSAUR.

FIRE.

THE SCRATCHES ARE DIFFICULT TO DISTINGUISH WITH THE NAKED EYE,

SO A 3-D RENDERING MADE WITH PHOTOGRAMMETRY

IS FINALLY BRINGING THESE SUPPOSED DINO MARKINGS

INTO FOCUS.

WOW!

I AM BLOWN AWAY AT ALL OF A SUDDEN,

THOSE SCRATCH MARKS LOOK LIKE SCRATCH MARKS.

ON THE RIGHT SIDE OF THE RIDGE,

I CAN NOW CLEARLY SEE LONG, THIN GROOVES,

EACH ABOUT AN INCH DEEP,

FOR ALMOST THEIR ENTIRE 6-FOOT LENGTH.

AND THIS PATTERN IS MIRRORED ON THE LEFT SIDE OF THE RIDGE,

SUGGESTING THE BILATERAL SYMMETRY OF A TWO-LEGGED ANIMAL.

THEN, NEFFRA NOTICES ONE MORE THING.

SEE THAT THERE ARE THOSE THREE INDENTATIONS, RIGHT THERE?

I THINK THAT'S THE IMPRESSION

OF JUST A MOMENT OF IT STANDING ON ONE FOOT.

WHAT DO YOU THINK, MARTIN?

YEAH, YEAH, YEAH.

ISN'T THIS EXCITING?

THAT'S AWESOME.

THE PHOTOGRAMMETRY MODEL REALLY BRINGS

THESE MARKINGS INTO FOCUS LIKE NEVER BEFORE

AND OFFERS COMPELLING EVIDENCE

THAT A LIVING, BREATHING DINOSAUR MADE THESE SCRATCHES.

THIS IS A MAJOR FIND, BECAUSE IT MAY GIVE US A GLIMPSE

INTO A LIVING DINOSAUR'S BEHAVIOR.

NOW THE NEXT STEP IS TO DETERMINE

WHAT KIND OF DINOSAUR MADE THESE SCRATCH MARKS.

I KNOW THAT ABOUT 100 MILLION YEARS AGO,

SEVERAL SPECIES OF DINOSAURS ROAMED THIS AREA.

AND I KNOW FROM THE FOOTPRINTS I SAW EARLIER

THAT TWO GROUPS LIKELY WALKED THROUGH THIS VERY SPOT--

PLANT-EATING IGUANODONS WITH THE FLESHIER FOOTPRINT

AND BIPEDAL, CARNIVOROUS THEROPODS

WITH THREE BIRD-LIKE DIGITS AND SHARP CLAWS.

SO, IF WE TAKE A LOOK AT THOSE PRINTS

AND LINE THEM UP WITH THE SCRATCH MARKS,

WE HAVE A MATCH.

THE SPACING OF THE SCRATCHES POINTS TO

AN ANIMAL WITH THREE TOES EQUIDISTANT FROM EACH OTHER.

SO, IF THESE MARKINGS WERE INDEED MADE BY A DINOSAUR,

IT WAS VERY LIKELY A LARGE, CLAWED THEROPOD.

SO HOW BIG IS THIS? I MEAN, THIS IS BIG, RIGHT?

THIS IS SOMETHING REALLY NEW.

I'VE NOT SEEN ANYTHING LIKE THIS.

AFTER 100 MILLION YEARS,

PHOTOGRAMMETRY MAY HAVE UNLOCKED THE IDENTITY

OF THE SPECIES BEHIND THESE SCRATCHES.

BUT THERE IS ONE MORE GIANT MYSTERY TO UNRAVEL--

WHAT ON EARTH WAS GOING ON HERE?

TO FIND OUT, I WANT TO DO SOMETHING A LITTLE UNORTHODOX,

AND CERTAINLY NOT HI-TECH...

REPLICATE THE SCRATCH MARKS

WITH A MODEL OF A THEROPOD FOOT.

OH, THIS LOOKS LIKE A PRETTY GOOD SPOT.

SO, ACTUALLY, THE SAND HERE

IS QUITE SIMILAR TO THE SANDSTONE.

THIS CREEK BED WILL SIMULATE

THE HABITAT THIS DINOSAUR LIVED IN.

LET'S GO AHEAD AND SEE IF WE CAN MAKE THE SAME KIND OF MARK.

BASICALLY IT WOULD HAVE BEEN

KIND OF A FORWARD TO BACKWARDS MOTION, RIGHT?

YEAH.

THEN IT WOULD HAVE BEEN BOTH.

IT WAS DOUBLE MARKS LIKE THAT...

LEFT FOOT, RIGHT FOOT, I GUESS.

YOU MAKE A PRETTY GOOD DINOSAUR. YEAH.

HONESTLY, THESE LOOK VERY SIMILAR

TO THE MARKS THAT WE SAW.

BUT WHY WOULD IT HAVE BEEN DOING THIS?

ONE OF THE THINGS THAT WE CAN SAY FOR SURE

IS THAT IT WAS A PRETTY ENERGETIC ACTIVITY,

AND SO WHAT WOULD ENCOURAGE IT TO BE SO ENERGETIC?

LET'S TRY TO TAKE SOME OF THE THINGS WE KNOW.

FIRST OF ALL, IT PROBABLY WASN'T DIGGING FOR WATER.

IT COULD HAVE JUST GOT DOWN AND DRANK THE WATER, RIGHT?

THAT'S RIGHT.

AND THE OTHER THING IS

IF IT HAD DUG A HOLE FOR WATER...

RIGHT.

...THE WATER WOULD HAVE PONDED UP IN THE HOLE

AND GOT RID OF THE SCRAPE MARKS.

WOW.

IT CERTAINLY WOULDN'T BE DIGGING FOR ROOTS

BECAUSE IT WAS A CARNIVORE, IT WAS A MEAT-EATER.

HMM.

MARTIN EXPLAINS THAT IT ALSO PROBABLY WASN'T BUILDING A NEST,

SINCE THEROPOD NESTS WERE ROUND.

SO, THEN WHAT COULD IT BE DOING?

HOW ABOUT FIGHTING?

COULDN'T THESE MARKINGS MEMORIALIZE

A DEADLY BATTLE BETWEEN BEASTS?

I'M IN COLORADO, TRYING TO UNDERSTAND

A GROUP OF MYSTERIOUS MARKINGS QUITE POSSIBLY LEFT

BY A THEROPOD DINOSAUR 100 MILLION YEARS AGO.

WHY EXACTLY WAS THIS SPECIES CLAWING AT THE GROUND?

COULD THIS BE THE FIRST REAL-TIME EVIDENCE

OF A DINOSAUR FIGHT IN PROGRESS?

CLUES FOUND IN DINOSAUR BONES

SUGGEST THEY DID DO BATTLE WITH ONE ANOTHER.

MANGLED TAILS, BATTERED BONES,

AND FOREIGN TEETH LEFT BEHIND IN JAW BONES

SUGGEST THAT THE PREHISTORIC ERA WAS A VIOLENT TIME.

SO, AMIDST ALL THESE CLASHES,

COULDN'T THEY HAVE ALSO LEFT BEHIND SOME GOUGES IN THE SAND?

SEEMS ENTIRELY POSSIBLE.

BUT IF THESE SCRATCHES WERE EVIDENCE OF A FIGHT,

WOULDN'T WE ALSO FIND MARKINGS LEFT BY THE SPARRING PARTNER?

THERE ISN'T ANY OTHER SET OF SCRATCHES

IN THE IMMEDIATE VICINITY,

SO, WHILE THIS THEORY IS TANTALIZING,

IT MAY NOT BE THE MOST PLAUSIBLE EXPLANATION.

I THINK WE'VE RULED OUT A LOT OF THINGS.

WHAT'S LEFT? WHAT BEHAVIOR DO YOU THINK THIS IS?

WELL, I THINK ONE OF THE IMPORTANT THINGS TO REMEMBER

IS THAT THESE CARNIVOROUS DINOSAURS

ARE THE ANCESTORS OF MODERN BIRDS.

FOR MORE THAN A CENTURY, SOME SCIENTISTS HAVE THEORIZED

THAT BIRDS AND THERAPOD DINOSAURS WERE LINKED.

AND NEW DISCOVERIES HAVE BOLSTERED THIS IDEA.

A SERIES OF VERIFIED FOSSILS FOUND IN CHINA

SHOW SOME LATER DINOSAURS WERE ACTUALLY FULLY FEATHERED--

A CLEAR LINK TO BIRDS.

AND FOSSILIZED SKULLS OF BABY DINOSAURS

BEAR STRIKING RESEMBLANCE TO ADULT BIRD SKULLS.

SCIENTISTS HAVE EVEN DEMONSTRATED THAT CHICKENS

WALK LIKE DINOSAURS WHEN RAISED WITH A PROSTHETIC TAIL.

SO, COULD THIS AVIAN LINK EXPLAIN WHY

A THEROPOD MADE SUCH DEEP, PERMANENT GOUGES IN THE EARTH?

SOME BIRDS THAT ARE GROUND-NESTING,

THEY DO THIS BEHAVIOR

LIKE THEY'RE BEGINNING TO BUILD A NEST,

BUT ACTUALLY WHAT THEY'RE DOING

IS SHOWING OFF TO THEIR PARTNERS.

IT'S PART OF A COURTSHIP OR A MATING RITUAL,

AND THAT, I THINK, IS WHAT WE'RE FINDING.

WOW.

WAIT. WHAT?!

FOREPLAY? MATING?

I DIDN'T SEE THAT COMING.

BUT TODAY, WE CAN SEE THE SAME SEDUCTIVE SCRAPING

IN ATLANTIC PUFFINS, AUSTRALIAN BRUSH TURKEYS,

PLOVERS, AND A NOCTURNAL GROUND-DWELLING

NEW ZEALAND PARROT CALLED THE KAKAPO.

SO, IT SEEMS OUR DINOSAUR SCRATCHES

WERE PROBABLY MADE IN THE NAME OF LOVE, NOT WAR.

ISN'T THATAMAZING?

TO HAVE ALL OF THOSE THINGS COME TOGETHER

ON THE EVIDENCE OF SOME SCRAPE MARKS.

I STARTED THIS INVESTIGATION A LITTLE SKEPTICAL,

BUT I'M AMAZED AT HOW MUCH CAN BE GLEANED

FROM A COUPLE OF SEEMINGLY RANDOM SCRATCH MARKS.

AND WHILE WE MAY NEVER KNOW WITH ABSOLUTE CERTAINTY

WHAT THE PREHISTORIC WORLD WAS TRULY LIKE...

FIRE.

...NEW TECHNOLOGIES CONTINUE TO DRAW ITS STAR PLAYERS

MORE FULLY OUT OF THE SHADOW OF EXTINCTION.

AND NOW, I'M DOWNSIZING FROM THE MAMMOTH TO THE MICROSCOPIC

TO INVESTIGATE WHETHER A RARE SPECIES

OF EARTH'S TINIEST MICROBES

COULD REALLY BE VISITORS FROM OUTER SPACE.

CALIFORNIA'S MONO LAKE.

NESTLED IN THE HIGH DESERT OF THE SIERRA MOUNTAINS,

THIS WONDER OF NATURE SEEMS VIRTUALLY BARREN

OF AQUATIC LIFE...

AND APPEARS TO BE FROM ANOTHER PLANET.

FOR DECADES, NASA HAS BEEN STUDYING

THE AREA'S UNUSUAL LANDSCAPE,

WHICH SEEMS TO BEAR STRIKING SIMILARITIES

TO THE SURFACE OF MARS.

SCIENTISTS ARE ESPECIALLY INTRIGUED

BY THE LAKE'S TUFA TOWERS--

THE ODDLY SHAPED LIMESTONE SPIRES

THAT TOWER ABOVE THE SURFACE.

EVIDENCE SUGGESTS THAT SIMILAR STRUCTURES

COULD EXIST ON THE RED PLANET.

BUT WHAT REALLY CAPTURED THE WORLD'S ATTENTION

WAS A STUNNING DISCOVERY MADE HERE IN 2010.

THAT YEAR, RESEARCHERS FOUND STRANGE BACTERIA THRIVING

IN THE INHOSPITABLE WATERS.

ITS BIOCHEMICAL COMPOSITION

APPEARED TO BE FUNDAMENTALLY DIFFERENT

FROM ALL LIFE AS WE KNOW IT.

SOME EVEN SURMISE THAT THESE BEINGS WERE NOT OF THIS WORLD.

WHILE THE TERM "ALIENS"

TYPICALLY CONJURES UP IMAGES OF LITTLE GREEN MEN,

MANY SCIENTISTS AGREED THAT THEY'D MORE LIKELY

BE TINY ORGANISMS INVISIBLE TO THE NAKED EYE...

LIKE THE MYSTERIOUS MICROBES OF MONO LAKE.

COULD THIS REALLY BE THE FIRST EVIDENCE OF ALIEN LIFE FORM?

MAYBE WE'RE LOOKING FOR SOMETHING SMALL, JUST LIKE THIS.

AND, I MEAN, IT'S COMPLETELY DIFFERENT

THAN ANY OF THE LIFE FORMS WE HAVE HERE ON EARTH.

MOST SCIENTISTS SEEM TO DISMISS

THE IDEA OF AN OTHER-WORLDLY ORIGIN...

...BUT I WANT TO SEE IF I CAN PUT THESE ALIEN RUMORS

TO THE TEST MYSELF.

SO I'M HEADING OUT TO MONO LAKE

FOR A CLOSE ENCOUNTER OF THE MICROSCOPIC KIND.

YOU DON'T USUALLY SEE THIS

WHEN YOU'RE WALKING THROUGH THE FOREST.

I'M HEADED OUT TO CALIFORNIA'S MONO LAKE,

ABOUT 200 MILES EAST OF SAN FRANCISCO,

TO INVESTIGATE AN EXTRAORDINARY CLAIM

THAT STRANGE BACTERIA FOUND AT THE SITE

CAME FROM OUTER SPACE.

SPANNING 65 SQUARE MILES,

THIS ANCIENT LAKE IS WHAT'S KNOWN AS A CLOSED BASIN,

SO WATER CANNOT FLOW OUT

BUT IS INSTEAD LOST THROUGH EVAPORATION,

LEAVING HIGH CONCENTRATIONS OF SALT AND MINERALS BEHIND.

THIS AREA REALLY IS BIZARRE.

SO, THIS LAKE IS ACTUALLY A LOT BIGGER THAN I EXPECTED.

IT'S GOT A SOMEWHAT-ELLIPTICAL SHAPE TO IT,

THERE'S A BUNCH OF ISLANDS.

TODAY THERE ARE NO FISH SWIMMING

IN WHAT'S COME TO BE KNOWN AS CALIFORNIA'S DEAD SEA.

SO, I WANT TO KNOW HOW THIS MICROBE CAN SURVIVE

IN SUCH AN INHOSPITABLE PLACE.

TO DO THIS, I FIRST NEED TO UNDERSTAND

WHAT MAKES THIS WATER SO TOXIC, BECAUSE ITS CHEMICAL COMPOSITION

COULD BE KEY TO UNCOVERING THE BACTERIA'S BIOLOGICAL SECRETS.

THE FIRST THING THAT WE HAVE TO DO

WHILE WE'RE OUT HERE IS FIGURE OUT WHY

THERE'S ALMOST NOTHING THAT LIVES IN THIS LAKE.

NOW, TO HELP ME DO THAT,

I'LL HAVE A FEW DIFFERENT INSTRUMENTS.

THIS IS SOMETHING THAT YOU WOULD USE

TO TEST THE CHEMISTRY OF YOUR POOL.

SO, THESE STRIPS ARE GOING TO HELP US

DETERMINE WHAT THE pH IS.

MEASURING THE LAKE'S pH LEVEL

WILL TELL ME HOW ACIDIC OR BASIC THE WATER IS.

NOW, JUST FOR REFERENCE,

MOST LAKES ARE GOING TO HAVE A pH OF 7.

SO ACCORDING TO THIS, MY pH STRIP SHOULD BE ORANGE.

LOOK AT THAT!

THE pH IS OFF THE CHARTS-- IT TURNED BRIGHT PINK.

MY SCALE ONLY GOES TO 8.5,

SO THIS MUST BE A pH OF 9 OR 10.

JUST FOR COMPARISON, BLEACH HAS A pH OF 12.

SO YOU COULD BASICALLY WASH YOUR WHITES IN HERE

AND HAVE THEM COME OUT LOOKING SPOTLESS.

I CAN ALSO GAUGE THE WATER'S MINERAL CONTENT

WITH THESE STRIPS.

HIGH LEVELS OF MINERALS ARE TYPICALLY HARMFUL

TO THE SKIN AND GILLS OF AQUATIC SPECIES.

THE HARDNESS OF THE WATER HAS A LOT TO DO

WITH HOW MANY METALS ARE IN IT,

MAYBE HEAVY METALS MAKING IT

SO THAT HARDLY ANYTHING LIVES IN THIS LAKE.

TOTAL HARDNESS-- VERY HIGH.

SOME METALS ARE MORE DANGEROUS THAN OTHERS.

SO, TO DETERMINE EXACTLY WHICH ONES ARE PRESENT,

I PULL OUT AN X-RAY FLUORESCENCE GUN.

THIS IS VERY NEW TECHNOLOGY.

I WOULD NOT HAVE BEEN ABLE TO DO THIS DECADES AGO.

WHAT I'M GOING TO DO IS I'M GOING TO PULL THIS TRIGGER,

OUT OF THE FRONT HERE IT'S GOING TO SEND

A HIGH-INTENSITY X-RAY BEAM,

AND THEN AS IT BOUNCES OFF OF DIFFERENT ELEMENTS,

IT'S GOING TO SEND BACK DIFFERENT SIGNALS,

WHICH IS GOING TO HELP ME INTERPRET WHAT'S IN HERE.

HOLY MOLY!

THERE'S BORON, MAGNESIUM,

AND ACTUALLY THERE'S A LOT OF ARSENIC IN HERE.

THESE LEVELS OF ARSENIC ARE REALLY, REALLY HIGH.

WE'RE LOOKING AT 2,000 TIMES HIGHER

THAN WOULD BE ACCEPTABLE TO DRINK.

HUMANS HAVE BEEN MINING THE CRYSTALLINE METALLOID

KNOWN AS ARSENIC SINCE THE DAYS OF ANCIENT GREECE.

THE ELEMENT IS USED TO PRODUCE A WIDE ASSORTMENT OF ITEMS--

FROM MEDICINES AND WOOD FURNITURE,

TO ELECTRONICS AND CHEMICAL WEAPONS.

BUT BECAUSE IT'S OFTEN ODORLESS AND TASTELESS IN COMPOUND FORM,

ARSENIC HAS ALSO BEEN KNOWN

AS THE PERFECT POISON THROUGHOUT HISTORY.

ICONIC VILLAINS LIKE THE ROMAN EMPEROR NERO AND THE BORGIAS

USED IT TO ELIMINATE THEIR FOES.

IF INGESTED, THE TOXIN CAN POSE SERIOUS HAZARDS

INCLUDING CANCER, NERVE DAMAGE, AND DEATH.

AND IT TURNS OUT THAT MONO LAKE

HAS ONE OF THE HIGHEST CONCENTRATIONS

OF ARSENIC ON THE PLANET.

SO IT PROBABLY ISN'T THE IDEAL BEACH DESTINATION,

UNLESS YOU'RE ONE OF THESE INVINCIBLE MICROBES.

YOU CAN SEE THOSE DARK ROCKS?

WE'RE GOING OVER THERE.

PERHAPS NO ONE KNOWS

THIS SO-CALLED ALIEN BACTERIA BETTER

THAN GEOMICROBIOLOGIST RON OREMLAND.

HE WORKED WITH THE NASA-SUPPORTED TEAM

OF RESEARCHERS THAT DISCOVERED IT BACK IN 2010.

TODAY, HE'S TAKING ME TO AN ISLAND ON THE LAKE

FOR A CLOSE ENCOUNTER.

HOLY SMOKES! LOOK AT THIS ONE.

THIS ONE IS BRIGHT RED.

YOU DON'T USUALLY SEE THIS

WHEN YOU'RE WALKING AROUND THROUGH THE FOREST.

NOPE.

WHEN IT WAS FIRST FOUND, THE MICROBE, DUBBED GFAJ1,

APPEARED TO RESEMBLE NO OTHER ORGANISM ON EARTH.

IT SEEMED TO REDEFINE OUR UNDERSTANDING

OF THE BUILDING BLOCKS OF LIFE.

EARLY TESTS INDICATED

ITS DNA SUBSTITUTED ARSENIC FOR PHOSPHOROUS,

ONE OF THE 6 ELEMENTS EVERY OTHER LIVING ENTITY REQUIRES.

IT WAS THRIVING ON A SUBSTANCE

THAT KILLS VIRTUALLY EVERYTHING ELSE.

ALL THESE MICROORGANISMS RIGHT HERE,

THEY GET ENERGY FROM THE ARSENIC.

THEY'RE PHOTOSYNTHETIC-- THEY'RE LIKE PLANTS

EXCEPT THEY'RE BACTERIA, THEY'RE MORE PRIMITIVE.

SO ESSENTIALLY, WE'RE LOOKING AT A GROUP OF ORGANISMS

THAT HAVE A COMPLETELY DIFFERENT PATHWAY

OF GETTING ENERGY THAN ANYTHING ELSE

THAT'S ON THE PLANET, AS FAR AS PLANTS GO.

YES.

AND THIS IS JUST THE PERFECT ENVIRONMENT FOR THEM.

AND THEY'RE RED BECAUSE OF THE PIGMENTS

THEY USE TO HARVEST THE LIGHT.

THIS ABILITY TO ADAPT TO SUCH INTOLERABLE CONDITIONS,

CLASSIFIES THESE BACTERIA AS EXTREMOPHILES.

EXTREMOPHILES CAN THRIVE

IN THE MOST FORBIDDING OF ENVIRONMENTS--

PLACES THAT ARE INTENSELY HOT, COLD,

ACIDIC, AND EVEN RADIOACTIVE.

THEIR REMARKABLE ABILITY

TO LIVE IN SUCH EXTREME CONDITIONS

HAS MADE THEM INSTRUMENTAL IN DEVELOPING

REVOLUTIONARY MEDICATIONS AND INDUSTRIAL PRODUCTS.

IT'S ALSO WHY THEY'RE CONSIDERED INVALUABLE

IN THE SEARCH FOR EXTRATERRESTRIAL LIFE

BECAUSE THEY SHED LIGHT ON HOW LIVING CREATURES

COULD WITHSTAND THE HARSHER CONDITIONS

THAT PREVAIL ON OTHER PLANETS.

MOST SCIENTISTS NOW BELIEVE THE MYSTERIOUS MICROBE

OF MONO LAKE IS SIMPLY AN EARTHLY EXTREMOPHILE,

BUT THE BACTERIA'S STAGGERING TOLERANCE FOR ARSENIC

IS UNIQUE EVEN AMONG THAT ADAPTABLE GROUP.

SO, IS IT POSSIBLE THERE'S A MORE OTHER-WORLDLY EXPLANATION?

THAT PROSPECT WOULD SEEM MUCH MORE PLAUSIBLE

IF WE HAD OTHER PROOF THAT LIFE DOES EXIST BEYOND EARTH.

SO FAR, WE DON'T.

BUT SOME ASTRONOMERS THINK WE COULD BE CLOSE

TO FINDING IT RIGHT HERE IN OUR OWN SOLAR SYSTEM.

IN 2016, NASA MADE AN ASTONISHING FIND ON ENCELADUS,

SATURN'S SIXTH-LARGEST MOON.

AN UNMANNED PROBE REVEALED STRONG EVIDENCE

OF HOT, HYDROTHERMAL ACTIVITY IN AN UNDERGROUND OCEAN

LOCATED NEAR THE MOON'S SOUTH POLE.

WITH VENT-HEATED, CHEMICAL-RICH WATERS,

ENCELADUS COULD CLOSELY RESEMBLE THE ENVIRONMENT

IN WHICH LIFE FIRST ORIGINATED ON EARTH.

IN OTHER WORDS, THE PLACE COULD BE TEEMING WITH ALIEN MICROBES.

SO, ASTRONOMERS ARE NOW PLANNING ANOTHER MISSION,

AIMED AT HUNTING THEM DOWN.

WHILE NASA CONTINUES TO PROBE

FOR SIGNS OF ALIEN LIFE IN OUTER SPACE,

I'M SEARCHING FOR IT RIGHT HERE IN CALIFORNIA.

BEFORE I TAKE ANY THEORY OFF THE TABLE,

I NEED TO TAKE A STEP BACK AND FIGURE OUT

HOW EXACTLY THIS LAKE GOT SO TOXIC IN THE FIRST PLACE.

I'M HOPING IF I CAN TRACE THE ARSENIC TO ITS SOURCE,

I'LL UNCOVER CLUES ABOUT THE ORIGIN

OF THE BIZARRE BACTERIA THAT'S FEEDING OFF OF IT.

WHAT DID YOU BRING?

I GOT SOME MAGNETOMETERS.

SO, I'M BRINGING IN GEOPHYSICIST JARED PEACOCK

TO HELP ME CONDUCT

A MAGNETOTELLURIC SURVEY OF MONO LAKE

THAT WILL TELL US MORE

ABOUT WHAT'S GOING ON DEEP BENEATH IT.

SO, WITH MAGNETOTELLURICS, OR MTs, AS WE CALL IT,

WE MEASURE THE EARTH'S ELECTRICAL RESISTIVITY.

WALKING AROUND ITS SHORES, I'VE NOTICED SEVERAL SPRINGS

BUBBLING UP FROM BENEATH THE SURFACE.

SPRINGS LIKE THIS USUALLY ORIGINATE

DEEP IN EARTH'S SUBSTRATE,

AND THEY COULD OFFER THE LAKE'S TOXIC CHEMICALS,

AND MAYBE THESE BACTERIA THEMSELVES,

A RIDE UP FROM THE BOWELS OF EARTH.

AN MT SURVEY USES ELECTRICAL AND MAGNETIC FIELDS

TO IDENTIFY VARIATIONS BENEATH THE EARTH'S SURFACE.

WITH THE DATA, IT THEN CONSTRUCTS A 3-D MAP

OF THE DIFFERENT GEOLOGICAL LAYERS.

SO, WE'RE MEASURING THE EARTH'S ELECTRICAL RESPONSE

TO THAT MAGNETIC FIELD,

AND THAT GIVES US ELECTRICAL RESISTIVITY.

PUT THIS ONE RIGHT HERE.

THIS IS TECHNOLOGY THAT CAN PLOT OUT AREAS

AS DEEP AS TENS OF THOUSANDS OF FEET.

SO, IT'S ESPECIALLY USEFUL FOR PETROLEUM

AND MINING EXPLORATION.

BUT TODAY I'M HOPING IT WILL UNCOVER THE SECRETS

OF ONE OF THE PLANET'S MOST EXTREME LIFE FORMS.

SO NOW WE FLIP THE SWITCH?

YEAH.SWEET.

LET'S HAVE A LOOK.ALL RIGHT.

BY PLUGGING THE SURVEY DATA INTO AN ALGORITHM,

WE CAN THEN CREATE THE 3-D MODEL

OF THE LAKE BED'S GEOLOGICAL STRUCTURE

AND SCAN FOR CLUES ABOUT THE SOURCE

OF ITS LETHALLY TOXIC ELEMENTS.

BUT THERE'S ALSO A BIG CLUE RIGHT BEFORE OUR EYES.

MONO LAKE IS SURROUNDED BY VOLCANIC TERRAIN,

AND VOLCANOES ARE A MAJOR SOURCE

OF THE LIFE BLOOD OF THESE BACTERIA-- ARSENIC.

SO AS THE SURVEY DATA STARTS COMING,

JARED EXPLAINS HOW WE'RE LOOKING FOR SIGNS

OF UNDERGROUND MAGMA CHAMBERS,

WHICH ARE THE HEART OF VOLCANOES.

SO, MAGMA IS VERY HOT, IT'S WARM, IT'S LIQUID,

SO IF WE HAVE A MAGMA CHAMBER,

IT WILL COME RIGHT UP AS A NICE BRIGHT SPOT.

HERE'S THE MOMENT OF TRUTH RIGHT HERE.

SO... HOLY MOLY!

SO, IF WE GO THROUGH THIS...THAT'S PRETTY DETAILED.

SO, HERE'S THE MAGMA CHAMBER

THAT'S UNDERNEATH THE MONO CRATERS.

OKAY, SO THAT'S...

IT'S ABOUT 10 KILOMETERS DEEP.

OH, MY GOODNESS!

AND THIS IS WHAT'S COMING OUT UNDERNEATH THE LAKE.

SO, WHAT'S RIGHT BELOW US.

WOW! SO A MASSIVE AMOUNT OF MAGMA IS FLOWING

SIX MILES UNDER OUR FEET.

USING THE RESULTS, JARED TRACES THE SOURCE OF THE MAGMA

BACK TO A 10-MILE VOLCANIC CHAIN

JUST SOUTH OF THE LAKE, KNOWN IRONICALLY AS THE MONO CRATERS.

BUT THESE CRATERS ARE THE WORK OF PLANET EARTH,

NOT ALIEN INVADERS.

THEY ARE ACTUALLY VOLCANOES THAT LAST ERUPTED ONLY 600 YEARS AGO,

AND THEY'RE STILL CONSIDERED ACTIVE.

SO, THEY ARE STILL SPEWING ARSENIC-RICH GASES

THROUGH A SET OF VENTS

WHICH LIE DIRECTLY BENEATH THE LAKE.

SO NOW WE KNOW HOW IT BECAME THE PERFECT HOME

FOR THESE STRANGELY TOXIC MICROBES.

BUT THE QUESTION REMAINS--

DID THOSE BACTERIA ORIGINATE HERE

AND EVOLVE TO WITHSTAND INCREASINGLY POISONOUS WATERS,

OR DID THEY HITCH A RIDE FROM OUTER SPACE

AND ARRIVE ALREADY WELL SUITED FOR AN ARSENIC-RICH ENVIRONMENT?

I'VE GOT AN IDEA FOR ONE MORE EXPERIMENT

THAT MIGHT SETTLE THIS QUESTION, ONCE AND FOR ALL.

THAT'S REALLY LOW.

WELL, THAT'S NOT WHAT WE WERE EXPECTING, WAS IT?

COULD MONO LAKE'S UNSTOPPABLE MICROBE BE FROM OUTER SPACE?

IF SO, IT WOULD HAVE NEEDED A RIDE TO EARTH.

SO, I WANT TO SEE WHETHER THERE'S EVIDENCE

OF AN INTERSTELLAR TRANSPORTATION SYSTEM

BENEATH THE SURFACE OF THE LAKE...

IN OTHER WORDS, A METEOR CRATER.

IF THERE IS, THIS WOULDN'T BE THE ONLY LAKE THAT FORMED

IN THE WAKE OF A COSMIC COLLISION,

SO-CALLED "METEOR LAKES,"

CRATERS FILLED BY RAIN AND RUNOFF,

EXIST AROUND THE GLOBE.

ONE OF THE LARGEST IS CANADA'S MANICOUAGAN RESERVOIR,

A RING-SHAPED BODY OF WATER THAT FILLED THE DEPRESSION LEFT

BY AN ASTEROID MORE THAN 3 MILES WIDE.

IS IT POSSIBLE THAT UNDER THE RIGHT CONDITIONS,

THESE EXTRAORDINARY LAKES

COULD PROVIDE A HABITAT FOR ALIEN LIFE?

IF SO, ALL IT WOULD NEED IS A RIDE TO EARTH.

AS A BIOLOGIST WHO SPENT A LOT OF TIME THINKING

ABOUT THE ORIGINS OF LIFE,

I KNOW OF SOMETHING CALLED THE PANSPERMIA HYPOTHESIS.

ACCORDING TO THIS THEORY,

LIFE FROM OUTER SPACE COULD COME TO OUR PLANET

ABOARD ONE OF THE THOUSANDS OF METEORITES

THAT CRASH HERE EACH YEAR.

MOST OF THESE ROCKS ARE TOO SMALL

OR LAND IN AREAS TOO REMOTE TO EVER BE NOTICED.

BUT IS IT CONCEIVABLE

THEY COULD ACT AS INTERPLANETARY TAXIS

AND TRANSPORT TINY ALIENS TO EARTH?

IN FACT, SOME SCIENTISTS THINK THAT'S ALREADY HAPPENED.

IN 1984, AN AMERICAN GEOLOGIST

IN THE ALLAN HILLS REGION OF ANTARCTICA

DISCOVERED WHAT BECAME KNOWN AS THE MARTIAN METEORITE.

ANALYZING THE SPECIMEN,

SCIENTISTS CONCLUDED THAT IT LIKELY FORMED

WHEN A VOLCANO ERUPTED 4.5 BILLION YEARS AGO...

ON MARS.

THE ERUPTION CATAPULTED THE ROCK INTO SPACE

AND IT EVENTUALLY LANDED ON EARTH.

BUT WHAT MADE THIS ROCK EVEN MORE UNIQUE

WAS A CONTROVERSIAL CLAIM

THAT THE CARBONATE GLOBULES IT CONTAINED

WERE PRODUCED BY MARTIAN MICROORGANISMS.

TODAY, THESE STATEMENTS REMAIN UNPROVEN,

BUT ONE THING IS CERTAIN--

THE CARBONATE GRAINS ARE SIMILAR TO THE ONES FOUND

IN MONO LAKE'S TUFA TOWERS.

SO, COULD THERE BE SOME COSMIC CONNECTION

BETWEEN THE MARTIAN METEORITE

AND THE MYSTERIOUS MICROBES OF MONO LAKE?

IF THERE IS, IT SEEMS WE'D HAVE TO FIND SIGNS

OF AN IMPACT CRATER HERE.

HEY, THANKS FOR COMING OUT HERE.

YEAH, OUR PLEASURE.I APPRECIATE IT.

TO TEST THIS THEORY, I'M GETTING SOME HELP

FROM GEOPHYSICISTS DALE RUCKER AND NIGEL CROOK.

I THINK THE EASIEST WAY FOR SOMETHING TO COME HERE

FROM ANOTHER PLACE IS THROUGH A METEORITE CRASH

AND THEN IT IS NOW HERE ON EARTH.

COULD THIS CRATER, THIS LAKE,

HAVE BEEN FORMED BY A METEOR?

WHAT WE'RE TRYING TO MEASURE

IS WHETHER THE EARTH IS CONDUCTIVE OR RESISTIVE.

DALE EXPLAINS THAT A METEOR IMPACT

WOULD COMPRESS THE GROUND

THEREBY BLOCKING THE FLOW OF ELECTRIC CURRENTS.

OPPOSITE OF THAT WOULD BE SOMETHING LIKE THIS SOIL,

THEN YOU WOULD GET A LOT OF ELECTRICITY

FLOWING THROUGH IT.

IF THE LAKE BOTTOM IS RESISTIVE,

IT WOULD INDICATE THAT IT'S HARD ROCK

LIKELY FORMED FROM A METEOR IMPACT.

TO HELP DETECT ANY EVIDENCE OF A COSMIC COLLISION,

NIGEL AND DALE HAVE BROUGHT ALONG

A MARINE ELECTRICAL RESISTIVITY METER.

LOOKS GOOD, HUH?

WITH THIS 500-FOOT-LONG CABLE,

WE'LL TRANSMIT ELECTRIC CURRENTS DOWN

TO THE BOTTOM OF THE LAKE.

A SET OF RECEIVERS ON THE CABLE WILL THEN PICK UP THE SIGNALS

AND MEASURE THE LAKE BED'S HARDNESS.

WE CAN THEN USE THAT INFORMATION TO GATHER DETAILS

ABOUT THE LAKE BED'S GEOMETRY AND COMPOSITION.

THAT'S REALLY LOW.

WELL, THAT'S NOT WHAT WE WERE EXPECTING, WAS IT?

AS THE DATA COMES IN, A PATTERN SLOWLY EMERGES.

IT LOOKS LIKE IT'S GETTING VERY CONDUCTIVE

AS WE GET INTO THESE LAKE-BOTTOM SEDIMENTS.

HUH.

SO, IF THIS WAS AN IMPACT CRATER,

WE'D BE SEEING HARD MATERIAL

AT THE BOTTOM INDICATING A METEOR.

IT'S ACTUALLY SHOWING THE OPPOSITE.

IT'S A VERY SOFT MATERIAL.

FROM WHAT I'M SEEING IN THE DATA,

IT IS NOT HARD ROCK,

THAT IT'S LIKELY SOME SORT OF SEDIMENTATION.

THE MATERIAL AT THE LAKE BOTTOM

LIKELY IS NOT FORMED FROM AN IMPACT CRATER

BASED ON THE RESISTIVITY VALUES THAT WE'RE SEEING.

WOW! OKAY, SO NO IMPACT MEANS NO METEOR.

IT MEANS, IN ALL LIKELIHOOD...

...NO ALIENS.

OF COURSE, THERE ARE OTHER THEORIES

ABOUT HOW THIS BACTERIA COULD HAVE COME FROM OUTER SPACE.

MAYBE IT WAS TRANSPLANTED BY SMALLER DEBRIS

THAT FELL TO THE PLANET FOLLOWING A COSMIC COLLISION,

OR IT COULD HAVE BEEN PLANTED HERE

BY AN INTELLIGENT SPECIES TO PROPAGATE ITS KIND.

BEING A PROUD MAN OF SCIENCE, THOUGH,

I'M NOT GONNA GO THERE.

UNTIL I SEE SOME CONVINCING EVIDENCE

TO SUPPORT AN ALIEN BACTERIAL INVASION,

I'M INCLINED TO CONCLUDE THE MICROBES OF MONO LAKE

ARE NOT VISITORS FROM AFAR

BUT HARDY EXTREMOPHILES BORN AND BRED ON PLANET EARTH.

AND, REALLY, THAT MAKES THEM EVEN COOLER.

BECAUSE, FOR ME, WHAT'S MOST COMPELLING ABOUT THIS STORY

IS HOW IT FORCES US

TO RE-EXAMINE THE BASIC CONCEPT OF LIFE ON EARTH.

THESE SEEMINGLY INVINCIBLE BACTERIA

ARE A STUNNING EXAMPLE OF THE RESILIENCE AND DIVERSITY

THAT CAN BE FOUND RIGHT HERE ON OUR OWN HOME PLANET...

LITTLE MICROSCOPIC REMINDERS

OF HOW REMARKABLE OUR WORLD REALLY IS.