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00:00Transcription by CastingWords
00:30Earth, a planet of life and almost infinite diversity.
00:36Yet one tiny link unites every living creature, plant or animal that ever existed.
00:46The single cell.
00:55The human body is made up of 60 trillion cells.
01:00Each as tiny as a grain of sand.
01:03But within every one of them is a genetic library.
01:06The functions of life are instincts and behavioral patterns inscribed in their volumes.
01:12In many ways, human cells today resemble those of the first life forms to thrive in Earth's
01:24primordial seas.
01:27Etched in the cell is the history of life on our planet.
01:31Life that evolved in bursts and swells over 4 billion years.
01:36END
01:52END
01:53END
01:55VIOLIN PLAYS
02:25VIOLIN PLAYS
02:55Planet Earth at the beginning, 4.6 billion years ago.
03:09Its surface erupted in a sea of molten magma.
03:13A billion years later, the planet was in the midst of a slow cooling process.
03:25Vapor rose to the sky, condensed, and fell to Earth in a torrential downpour.
03:30In the aftermath of the seemingly endless deluge, the primordial ocean was born.
03:39The atmosphere, after the formation of the ocean, was heavy with carbon dioxide, much like the planet Venus today.
03:52Earth was sealed off by thick clouds, and the lone streaks of sunlight that penetrated the cloud mass tinted the sky orange.
04:05Earth was like a giant steam bath with ocean temperatures soaring over 300 degrees Fahrenheit.
04:11But in this primordial soup, the building blocks of life were accumulating.
04:25Meteorites showered the Earth, perhaps bringing amino acids necessary for the formation of life.
04:31And then one day, four and a half billion years ago, an asteroid the size of Mars collided head-on with Earth.
04:50This giant impact was the greatest event in our planet's early history.
05:02The impact was of such phenomenal magnitude that it carved out part of the Earth's mantle and hurled it into outer space.
05:14A portion of the torn mantle was drawn back to Earth.
05:20The fragments of debris scattered into space were swept up by powerful gravitational forces.
05:32They formed a new satellite, which would eventually circle the Earth.
05:39This was the birth of the Moon.
05:50The giant impact shook the Earth to its core.
05:55On the ocean floor, rows of hydrothermal chimneys surfaced, spouting molten rock and volatile chemicals.
06:20Like a towering sentinel, the Moon stood watch over the roiling seas.
06:33The distance between Earth and the Moon was half what it is today, creating huge ocean swells and enormous tides with its gravitational pull.
06:41As the primordial ocean simmered, chemical reactions created complex new molecules.
06:55Some, such as hydrogen cyanide, would have been lethal to humans.
06:59Tiny molecules of these toxic compounds combined to form larger ones.
07:12Out of this mix, other molecules that would eventually form DNA, the blueprint of a living cell, took shape.
07:20This first step toward life would take nearly a billion years to complete.
07:33Eons later, no one can explain how the graceful double helix formed.
07:38Transforming inanimate compounds into living cells.
07:43Cells that could grow and reproduce.
07:47The catalyst of life remains unknown.
07:50This is White Island, a tiny land formation off northern New Zealand's volcanic coast.
08:11The geological setting here mimics conditions on Earth in its early years.
08:17Like its volatile ancestors, this speck of an island is a steaming cauldron of activity.
08:27A noxious mix of hydrogen sulfide and sulfuric acid gas spews from the depths of the crater.
08:36In this remote locale, the search has begun for clues to the origins of life.
08:53When life first appeared, scientists believed that the Earth was full of places like this one.
08:59Barren landscapes showered with hydrogen sulfide and sulfur, forming a crusty surface.
09:15This boiling water contains poisonous hydrogen sulfide.
09:19Is it possible that life can exist at nearly 200 degrees Fahrenheit?
09:28A microscopic view of the samples reveals scores of tiny, bar-shaped creatures.
09:43They are bacteria, and may be the closest modern link to the first life forms on Earth.
09:53Billions of years ago, the planet's first organisms thrived in a toxic soup that would destroy plants and animals today.
10:01But over time, a new recipe for life would emerge.
10:18At the University of California, Santa Cruz, Dr. David Diemer investigates the origins of life.
10:24Sometimes mixing evolutionary detective work with music.
10:31The piece he is playing is an interpretation of the human DNA sequence.
10:39DNA is a nucleic acid, carrying the genetic codes of all the proteins necessary for life.
10:46Two symmetrical chains within the double helix spiram about each other, rising and falling in harmony, like the right and left hands on a piano.
11:03The origin of life had to have occurred using the sorts of chemicals that were available on the early Earth.
11:10Comets and meteorites and very small dust particles falling back to the Earth could have brought some of these organic compounds back to the Earth's surface.
11:21What I do know is that if it did get released, at least these kinds of molecules would float on the surface of the ocean.
11:29And as they floated on the surface, like a very thin film of oil, just as we have oil slicks today, wave action and tides and winds would bring this to beaches.
11:41And, you know, you can go down to the beach today and walk along, you'll see kind of a froth.
11:46And all that froth is these kinds of lipid-like molecules that are forming those bubbles that we see even today on oceans.
11:52And I can imagine that same thing would have been happening 4 billion years ago, thereby being concentrated on these so-called intertidal zones and being acted upon by heat and sunlight.
12:08Inside the thin membrane of these bubbles, the elements of life were accumulating.
12:13In his laboratory, Dr. Diemer is recreating nature's primordial experiment, forming bubbles by mixing compounds found in ancient meteorites with water.
12:28He hopes to find out how cell membranes may have formed.
12:33The surface of the bubble is enlarged.
12:41In the middle is the membrane, through which surrounding matter is readily absorbed.
12:50What I see there is what must have happened on the early Earth in a tide pool environment.
12:56Dry down, lipid-like molecules get dry, they capture other molecules.
13:00The tide comes in, the rain falls, fills the pool, and just this kind of reaction must have occurred.
13:09The birth of life was perhaps a random and inevitable event.
13:14Inside the cell membrane, chemical reactions took place.
13:19The elements of life combining through trial and error to create what some have called the finest, most impressive piece of molecular architecture.
13:27The DNA strand.
13:31The first living things on the planet were probably very simple single cells, with one important trait distinguishing them from inanimate matter.
13:46A permeable membrane to absorb nutrients.
13:54Feasting on the ocean's bountiful supply of amino acids, they somehow managed to replicate themselves.
14:00Fragile bubbles on a foamy shoreline, Earth's first life forms were modest.
14:17Their origins remain to this day one of life's greatest secrets.
14:21Christmas Day, 500 miles off the coast of Acapulco, Mexico.
14:39On board the Atlantis II, a research vessel operated by the Woods Hole Oceanographic Institute, is a team of scientists led by Dr. Richard Lutz, a marine ecologist from Rutgers University.
14:58By using the latest in underwater camera technology mounted on Alvin, one of the world's deepest diving submersibles, Dr. Lutz is hoping to photograph the remains of an underwater volcano that erupted here four years ago.
15:20Alvin's crew are veterans of deep oceanic dives, and they know that once clear of their mothership, they're on their own.
15:39Their destination is a spot on the ocean floor known to have active hydrothermal vents.
15:54Okay, mainline, sir, pick it up.
15:5625 meters.
16:02For the next 90 minutes, they will descend into an inky blackness
16:07and the crushing pressures a mile and a half beneath the surface of the ocean.
16:25Dept. 2417 meters. 82 off the bottom. Call you from the bottom.
16:29As Alvin nears the bottom, the exterior lights are switched on, illuminating an astounding seascape.
16:45The remains of a lava flow stretching across the ocean floor.
16:52Smoking the volcanic chimneys billowing plumes of superheated water.
16:56The gushing liquid is rich in hydrogen sulfide, so concentrated that it would be a toxic waste site on land.
17:11The sea floor is alive with creatures living near the vents.
17:22Crabs, bathysaurus fish, tube worms, in all, more than 300 new species have been sampled and identified.
17:31The scientists retrieve a foam board they had placed there a week earlier.
17:46To their surprise, it is completely covered with bacteria.
17:49Deceptively lifeless, the deep sea is actually teeming with bacteria, one of the planet's earliest life forms.
18:05The breeding ability of these modern organisms far exceeds the expectations of the Alvin scientists.
18:15Their success perhaps linked to a diet once shared by their ancestors.
18:22Hydrogen sulfide from the Earth's core.
18:25Bacteria that fed on hydrogen sulfide 3.8 billion years ago are considered the first complex organisms in the evolutionary chain.
18:49Earlier life forms simply reproduced themselves using organic matter absorbed from their surroundings.
19:05By extracting additional energy from the nutrients in the sea vents, these bacteria thrived.
19:11Over time, some developed hard shells.
19:17Others, soft membranes.
19:22Ironically, all life forms, including humans, can trace our ancestries to the most primitive of organisms spawned in a sea of toxins.
19:33Oxygen was a poisonous gas to early life on the planet.
19:49Three billion years ago, the Earth was enshrouded in thick clouds, heavy with carbon dioxide and water vapor.
19:55Together, the mineral-rich water and CO2 formed new compounds, releasing oxygen into the atmosphere.
20:06While bacteria thrived in the Earth's new oceans, land, by contrast, remained a stark and desolate place.
20:16Continents had begun to take shape, but were still uninhabited.
20:25Then, half a billion years ago, rumbling with new energy, planet Earth remodeled itself.
20:33Separated continents began to collide.
20:43At points of impact, the steady upthrust of Earth eventually formed huge mountain ranges like today's Himalaya.
20:50The towering peaks diverted the jet streams, creating clouds and rainstorms.
21:11Torrential downpours sliced into mountain sides, forming valleys.
21:15Out of the deluge, rushing channels of water eventually converged into rivers of immense proportion.
21:24In the beginning, as wind and rain eroded the surface of the Earth, minerals from land flowed into the ocean.
21:42New ingredients to season the primordial soup.
22:01The minerals reacted with carbon dioxide, forming new compounds and releasing oxygen.
22:06But it would take another two and a half billion years for oxygen to saturate the atmosphere, making it habitable for today's life forms.
22:23As this greenhouse effect weakened, the planet began to cool.
22:26The thick clouds to dissipate, and rays of sunlight penetrated the seas.
22:33These environmental changes would soon play a significant role in stimulating new life.
22:49This is Pilbara, a forgotten stretch of desert in northwestern Australia.
22:56This region was at the bottom of the shallow sea three and a half billion years ago.
23:02The aborigines of Pilbara have many legends that tell of this place, where they believe land was first created.
23:09And it is here that scientists are piecing together a creation story of their own, in their search for the first evidence of life.
23:18In this dusty outback, Dr. Mike Freeman of the Western Australia Geological Survey Bureau shares an important discovery made in 1992.
23:28This contains the micro-fossils, which are the order of 3,460.
23:43This contains the micro-fossils, which are the order of 3,460.
23:49This contains the micro-fossils, which are the order of 3,460 million years old.
24:00Very, very old.
24:02In fact, this is one of the oldest rocks in existence today.
24:09Within lie traces of life from an ancient sea, an organism barely one one-hundredth of a millimeter long.
24:18The surrounding rocks show evidence of stromatolites, the fossilized remains of cyanobacteria,
24:31microscopic creatures resembling a chain of beads.
24:36Cyanobacteria are asexual organisms that reproduce without swapping genetic information with a mate,
24:44so they evolved little over time.
24:47Modern species look virtually the same as they did billions of years ago.
24:54Cyanobacteria get their name from their blue-green pigmentation, the color cyan.
25:03We know it as blue-green algae.
25:08The first plant life on Earth would be the descendants of this primitive organism.
25:13Unlike early life forms, these cells exploited their surroundings to create their own food.
25:22Within their cell walls, cyanobacteria used energy, combining water and carbon dioxide molecules abundant in seawater to create glucose.
25:40Like antennae, these chlorophyll molecules in the cell caught the sunlight, transforming it into energy.
25:49A byproduct of this process, oxygen, would one day spark the evolution of more complex life forms.
26:01This revolutionary process is, in fact, photosynthesis, used by all plants today.
26:12Two and a half billion years ago, seas separated lifeless continents.
26:20In Western Australia, those seas are now land formations.
26:26On the exposed mountainsides, a mysterious black layer of Earth stretches as far as the eye can see.
26:35In 1992, a team of researchers, headed by Professor Tomohiko Taira, with the Tokyo University Institute of Oceanography, launched a study to find out what it was.
26:52It's totally black.
26:55The blackness rubs off on your hands.
27:00This mass contains a lot of organic carbon.
27:04It's almost like charcoal.
27:06In fact, it's an ancient mass of organic carbon, the oldest source of oil on Earth.
27:13After several years of research, Professor Taira and his team concluded that this thick black layer of carbonaceous rock, or chert,
27:23was a massive accumulation of cyanobacteria fossils, deposited here three billion years ago.
27:32Microisotopic studies reveal the presence of organic matter, proving the presence of ancient life here.
27:42These fossilized remains, 130 feet deep, are evidence of cyanobacteria's once dominant role early in the planet's history.
27:51Under different circumstances, these organic deposits might have become oil or coal.
27:58The surface that I'm standing on now, the exposed stratum here, is actually the layer of ancient sea bottom.
28:11And the same layer of sea floor is connected from here all the way out to the horizon, extending over this entire area.
28:19In other words, I think that back then, cyanobacteria had multiplied and spread over the whole sea.
28:26The sea wasn't lifeless, rather it was teeming with life.
28:31And that's what we've just witnessed.
28:36The colony of blue-green algae that blanketed these ancient seas near present-day Australia,
28:46was the Earth's first documented population explosion.
28:51Its success would eventually transform the face of the planet.
29:06The Hamelin Pool near Shark Bay in Western Australia.
29:13This ecosystem bears the fruit of nearly three and a half billion years of evolutionary change.
29:23But cyanobacteria from ages past still blanket the rocks below the waterline.
29:35Floating in the open sea, the concavities of gas, buoyancy devices, allowing them to rise and fall with changing light intensity.
29:47As photosynthesis occurs, they excrete bubbles of oxygen.
29:56Soon, the ancient waters brim with oxygen.
29:59But most of it would not yet make it into the atmosphere.
30:04Iron compounds, ferrous salts from the sea, combine with the oxygen to form ferric oxide, painting the ocean floor a thick, rusty red.
30:18Oxidized iron from the sea also colors the landscape of Pilbara.
30:23Almost everywhere else on the planet where cyanobacteria thrived, major iron deposits were formed.
30:28Billions of years ago, colonies of cyanobacteria swept across the oceans of the world.
30:33In time, all of the iron in the sea fell on the sea, Ooze.
30:36In time, all of the iron in the sea became affidavit.
30:41Almost everywhere else on the planet where cyanobacteria thrived, major iron deposits
30:47were formed.
30:52Billions of years ago, colonies of cyanobacteria swept across the oceans of the world.
30:59In time, all of the iron in the sea was oxidized.
31:05But cyanobacteria continued to release oxygen at astounding rates.
31:20Great environmental changes were on the horizon as oxygen gained a foothold in the atmosphere
31:26and the once volatile orange skies faded softly into blue.
31:33As the chemistry of Earth's atmosphere shifted, what happened to the single cell bacteria that
31:44had lived on hydrogen sulfide?
31:48Their evolution is linked to the rise of more complex life forms.
31:59The sea, once awash in hydrogen sulfide, was now rich in oxygen, thanks to the highly
32:06adaptive cyanobacteria.
32:09But oxygen was a life-threatening poison to bacteria like these that had survived so long
32:14on hydrogen sulfide.
32:18The rising spherical bubble is full of oxygen.
32:21Once exposed to the gas, the bacteria weaken and eventually die.
32:29How did the ancient life forms overcome the oxygen crisis?
32:40Soft membrane bacteria adopted a run-for-your-life defense strategy, staying clear of the gas as
32:48much as possible.
32:56The bacteria with hard shells found ways to exploit their new situation.
33:03Coming into the oxygen-rich environment, they were evolutionary pioneers.
33:16Delta del Ebro, Spain lies due west of Barcelona on the Mediterranean Sea.
33:22Locals call it the bull's horns because of its shape.
33:28Sewage water from the river flows into this region, making it an ideal breeding ground for
33:33bacteria.
33:36Microorganisms from ancient times still thrive here.
33:41Blue-green cyanobacteria blanket the surface of this slimy landscape.
33:48Here on the Delta, scientists dig for clues about how early microorganisms adjusted to the
33:55oxygen infusion in their environment.
34:00This is from a brick.
34:02See that?
34:03And it's completely colonized by these bacteria.
34:09They just will grow on anything.
34:11They'll grow on volcanic rocks or whatever you give them.
34:18Biologist Dr. Lynn Margulis of the University of Massachusetts in Amherst says that bacterium
34:25are remarkably adaptive, unlike many creatures that came after them.
34:32You have to think of them as not being single.
34:34You have to think of them as being many, many kinds.
34:37And some of them will just die because we let the oxygen come in contact.
34:42But many of them, most of them, will just wait until the oxygen goes away.
34:48There's others that will use the oxygen but low concentration.
34:50There's others that use it at somewhat higher concentration.
34:54So they line up as to what they can handle.
34:59The samples that Dr. Margulis collects from the Delta appear to be mud, but they're actually
35:05living colonies of bacteria.
35:10This wedge of green mat is cyanobacteria.
35:15Below it, a thick colony of bacteria that feeds on hydrogen sulfide.
35:22Only an inch from the surface, ancient bacteria survive today.
35:30When animals go extinct, they're gone, they're finished.
35:32But when bacteria change, they keep the old ones and add the new ones.
35:38So there's no real loss at all.
35:40So these anaerobes are still the way they have been many years.
35:44A closer look at the Delta sample reveals something new.
35:49A thin pink layer separates the oxygen-producing tier of cyanobacteria above from the bacteria
35:56subsisting on hydrogen sulfide below.
36:09Observing this pink layer, Dr. Margulis discovered some bacteria that behave in a curious manner.
36:15This cylinder is a cyanobacterium exhaling oxygen.
36:25But instead of dying on exposure to the gas, the small surrounding bacteria advanced toward
36:31it.
36:32Dr. Margulis believes that a similar phenomenon occurred in the ancient seas as oxygen waste
36:39became a key part of the life cycle.
36:43For a time, all life in the sea, including the cyanobacteria that produced it, was threatened
36:55by the infusion of oxygen.
36:58To survive and eventually evolve, the hard-shelled bacteria first developed enzymes to neutralize
37:05the damage caused when oxygen reacts with organic molecules.
37:12Soon, these survivor cells learned how to harness oxygen as an energy source, dramatically increasing
37:19their activity level and becoming fierce aggressors.
37:29To survive, the soft-membrane bacteria from the habitat rich in hydrogen sulfide united with
37:36other bacteria, enlarging their body in self-defense.
37:48They pooled their DNA in the core of this microorganism and encased it in a new membrane.
37:55In this way, the cell nucleus was born.
37:59Now, as oxygen further penetrated the air and sea, two distinct organisms with specialized functions
38:10were developing.
38:11One became a living power plant.
38:17The other had an enormous data bank in its cell nucleus.
38:22Together, these simple life forms would transform the face of the earth.
38:32billions of years of evolutionary progress have led to a rich diversity of life across the
38:46globe today.
38:51All animals, including humans, share the same basic cell structure as the planet's first microorganisms.
38:59At the cell's core is the nucleus, an enormous data bank full of genetic information.
39:09Moving around the nucleus are small organs, mitochondria, in various shapes and sizes.
39:16Their job is to supply the cell with all the energy it needs and to help it breathe.
39:24The birth of this cell is one of life's first great adaptations, the merging of the ancient
39:30hard and soft-shelled bacteria.
39:34How could these once-competitive organisms coexist as one life form?
39:43The University of Tennessee in Knoxville, where Dr. Quang Jian, a specialist in cell biology, inadvertently
39:50witnessed the beginnings of a cellular partnership while running an experiment.
39:58In 1969, Dr. Jian was studying the ecology of amoebas he had collected from various lakes
40:05around the country.
40:08One day, he discovered that most of the amoebas he was cultivating were dying, infected by highly
40:14toxic bacteria.
40:19Removing the dead amoebas one by one, he was surprised by what he found.
40:25One amoeba, infected like the others, had somehow managed to survive.
40:32Examining the single-celled animal, he was stunned to find live bacteria inside.
40:44Dr. Jian decided to try another experiment on the same amoeba, five years later.
40:56When he extracted the foreign bacteria from inside the amoeba, a strange thing happened.
41:06As soon as the bacteria were removed, the amoeba lost its energy.
41:11Initially threatened by the bacteria, a symbiosis had developed between the two.
41:20Separated from this cooperative relationship, they both died.
41:31The bacteria's dependence on amoeba.
41:34From the very beginning, we tried to culture these bacteria outside amoeba, but we have not
41:40been able to culture them.
41:42They grow only within amoeba, and so they are getting something from amoeba for their survival,
41:51and we are trying to find that out.
41:53Now in the meantime, we have learned that amoeba produce a few proteins that are used by bacteria,
42:03and so it's a kind of exchange.
42:04The phenomenon Dr. Jian witnessed in his laboratory may have imitated evolutionary patterns in the
42:14early seas.
42:18Two billion years ago, two very different microbodies merged to create an entirely new organism.
42:26Success would ultimately lead to the proliferation of new species across the globe.
42:35The cell is the foundation of all life.
42:39Without it, no living creature could eat or breathe or grow.
42:44Our very existence depends on it.
42:50Every animal cell requires the nucleus to transmit information from its genetic data bank to the
42:55mitochondria, and the mitochondria in turn to fuel the cell with energy.
43:06When these microbodies work together, a cell has the energy to respond to environmental pressures.
43:19Throughout history, creatures that cooperate ensure their future, while building increasingly
43:25complex ecosystems.
43:36It took some two and a half billion years for life to evolve beyond primitive microorganisms.
43:42But when change came to the planet's oceans, it was dramatic.
43:57New creatures of every shape and design tried their luck in the game of survival.
44:03But for millions of years, longer than the entire history of man, only one of them ruled the deep.
44:17The success of this aggressive carnivore may have triggered the planet's first population explosion.
44:27The sea, a vast staging area for evolution.
44:3110,000 new species, each more curious looking than the next, developed during this period.
44:40The better the design, the greater the chance of survival.
44:54Yet few of these creatures, including the once fearsome predator, would rise through the ages.
45:12Two billion years ago, only one tenacious life form thrived in our ancient seas.
45:19Today, life flourishes in every biosphere across the planet.
45:27We owe this abundance, the millions of plants and animals that grace the land, the sea, and
45:33the skies of planet Earth to life's smallest unit, the single cell.
45:39We owe this enlightenment.
45:50We owe this lecha.
45:51Let him sell.
45:52Amen.
45:52Amen.
45:52From the benefit.
45:53Amen.
45:54Amen.
45:54Amen.
45:55Amen.
45:56Amen.
45:59Amen.
46:00Amen.
46:01Amen.
46:02Amen.
46:04Amen.
46:05Amen.
46:05Amen.
46:06Amen.
46:07Amen.
46:08Amen.
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