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00:01How did life begin?
00:04It's one of the most fundamental and difficult questions,
00:07and has challenged us for eons.
00:11For years, scientists have been investigating this extraordinary puzzle,
00:16trying to figure out how non-living matter could have come together to form a living thing.
00:25It's a quest that drives scientists to look for clues at the very ends of the Earth,
00:31and even deep into space, searching for the secret of life.
00:55Our planet teems with life.
00:58From the highest mountain to the deepest ocean, life is everywhere.
01:05But how did it begin?
01:10How did life emerge on what was once a lifeless planet?
01:16I think it's just one of those big questions.
01:18I mean, people like to know where they're from and how they got there.
01:22Science now hopes to be able to answer this age-old question.
01:27Huge strides have been made, and extraordinary theories are now being investigated
01:33by some of the world's leading scientists.
01:36Some propose that life emerged from a warm volcanic pool.
01:40Some suggest it began deep on the ocean floor.
01:44And others believe that it developed out in the blackness of space.
01:49This is the time to be alive and working on this field of origin of life,
01:53because we now have the confidence that there are scientific ways of tackling the problem,
01:59but there's still so many unanswered questions.
02:02We want to know what's on our planet.
02:05We want to know what's out there in the universe.
02:08We can't help but be fascinated by it.
02:10A first step to understand how life began is to try to figure out where it began.
02:19For generations, it was assumed that life began on the Earth.
02:23Then, in 1903, the Swedish chemist Svante Arrhenius came up with an outlandish idea, panspermia.
02:35His theory is that life was created in space or on another planet,
02:43and the seeds of life dispersed out into new worlds.
02:53NASA scientist Scott Sanford investigates the possibility that life may have started in space.
03:00Panspermia is not totally impossible.
03:02We know samples of Mars have made it to the Earth.
03:06So, if you had life on Mars, you know, maybe it could have been delivered to us in that way.
03:13But even if panspermia did explain life getting started on the Earth,
03:17it doesn't explain how life got started in the first place.
03:19Sanford is not convinced that life itself was delivered to the planet,
03:23but he does believe that some of the starting materials, the building blocks of life,
03:28came from outer space.
03:31And their delivery system was a comet.
03:35Comets are delivering building blocks.
03:37They're not delivering living systems.
03:39They're delivering the components from which you might be able to make living systems.
03:43Comets are made up mainly of water and dust,
03:46with traces of carbon dioxide, methanol, and ammonia,
03:50all frozen into a giant, dirty snowball.
03:53Sanford believes that they also contain small numbers of organic compounds,
03:58some of the building blocks of life.
04:01But there's a problem.
04:02How did they get there?
04:04These building blocks are almost always put together by living things.
04:08They are complex carbon-based molecules like proteins, carbohydrates, and nucleic acids.
04:16So how did building blocks end up on a comet?
04:19Unlocking this riddle is the first step to understanding this theory of the origin of life.
04:25Sanford suspects that the unusual conditions on comets
04:29might lead to the formation of these organic molecules.
04:33So he sets up an experiment to test his idea.
04:37His first task is to recreate temperature conditions found in space where the comets roam.
04:44He has to achieve temperatures approaching minus 450 degrees Fahrenheit.
04:50To get an idea just how cold that is,
04:54look at what happens to air when it is cooled to below minus 300 degrees Fahrenheit.
05:00That's liquid air, basically.
05:02And you can demonstrate this by taking, let's say, a balloon,
05:06which is simply air in a container.
05:09When Sanford places the balloon in the liquid nitrogen,
05:12the air inside it cools, and some of the gases turn into liquid.
05:16And then when I remove it, you can see the balloon is flat,
05:19but as it warms up, it will return into a gas and blow the balloon back up.
05:25This only happens because the liquid nitrogen is at a very low temperature.
05:29So if we were to put this nitrogen in the machine back there,
05:32it would turn into a solid.
05:34So in fact, this liquid nitrogen, as cold as it is,
05:36is positively tropical compared to the kind of temperatures we normally work at
05:40when we're doing these simulation experiments.
05:45Whoops, we popped it.
05:50Sanford introduces substances found on comets,
05:53such as ammonia, carbon dioxide, and methanol, into his comet simulator.
05:58They instantly freeze.
06:03The sample is then bombarded with radiation from a hydrogen lamp.
06:12This simulates what happens when the comet receives radiation,
06:16for example, cosmic rays and gamma rays,
06:19and then passes close to the sun.
06:24Radiation and heat can transform the simple molecules
06:28into an array of organic compounds,
06:31ranging from proteins to amino acids.
06:35And Sanford uncovers the secret of how this transformation occurs.
06:41Some comets pass around our sun in highly elliptical orbits.
06:48When they are far from the sun, the molecules that have been irradiated
06:52are tightly locked in place, frozen into a solid chunk of ice.
06:56But when they get closer to the sun, things warm up,
06:59and the molecules get a chance to make their move and react.
07:03If you start to warm that ice up so that things can move a little,
07:06then they start to find each other and they react.
07:08But they don't react with their preferred partner,
07:10the person who would make them the most stable.
07:12They react with whoever they're next to.
07:13So you have these marriages of convenience.
07:15And as a result, the chemistry is not the kind of chemistry
07:17you think of, you know, in your freshman chemistry laboratory.
07:21Sanford shows how the building blocks of life can be created on the comet.
07:25But how do they get down to the surface of the Earth?
07:29A comet can deliver material to the surface of a planet in several ways.
07:34Of course, the whole comet can run into the planet,
07:36but that's rather a destructive way to do it.
07:41But more elegantly is to have the comet shed dust,
07:44as we see in a comet's tail.
07:46And that dust can then hit the planet's upper atmosphere,
07:49slow down without burning up, and then settle down to the surface.
07:52We have comet dust raining down on us all the time, even now.
07:55It's an incredible theory
07:57that comets can rain down the chemistry set needed to start life.
08:05So in February of 1999,
08:08NASA launches a bold mission to intercept a comet and return with a sample.
08:13It's a chance to test Sanford's theory.
08:26After five years of flight, the probe, codenamed Stardust,
08:30arrives at its target, just behind a comet known as Vilt 2.
08:37Dust particles from the comet's tail stream into a honeycomb collector
08:41filled with a specially designed aerogel.
08:48The sample trapped inside the aerogel
08:50is now sealed inside the return capsule.
08:56Two years later, in 2006,
08:58it slams into the Earth's atmosphere and crash lands into the Utah desert.
09:04The Stardust capsule survives the journey,
09:07and a team of scientists open it to examine the contents.
09:13To their great relief, the mission is a success.
09:16The aerogel inside the collector is peppered with tiny particles of comet dust.
09:22When scientists at NASA analyze the dust,
09:30they discover a vast array of complex organic chemicals,
09:35including aminos and hydrocarbons.
09:37This confirms Sanford's theory that comets contain building blocks of life.
09:49When you want to make life on a planet,
09:50you don't necessarily have to start from scratch on that planet,
09:53but that delivered to the planet from outer space may be compounds
09:57that can play important roles in getting everything going.
09:59It's amazing to think that life could have been kick-started using organic building blocks delivered from space.
10:08But one British scientist thinks that life itself was created on board a comet.
10:15Does that mean we are all descended from an alien life form?
10:18The search to find out how and where life began has puzzled scientists for generations.
10:29Chandra Wickram Singha, professor of astronomy at the University of Cardiff,
10:35agrees that comets had a role in the birth of life.
10:38But he believes that life itself began on a comet.
10:41Comets are the best places for life to originate.
10:48Our planetary system is surrounded by a hundred billion comets.
10:54So you are multiplying the odds in favor of life starting on any one of those comets,
11:01over that on the Earth, by a huge factor.
11:04Wickram Singha proposes that the organic molecules found inside comets
11:09came together to make the first single-celled life forms.
11:14It's a bold and controversial theory.
11:16At the beginning we were regarded as heretics,
11:19would have been perhaps burnt at the stake if we lived in medieval times.
11:23We were certainly mavericks, there's no question about it.
11:26Wickram Singha's radical claim is that cold, icy comets
11:31not only contain complex organic compounds,
11:34but also the other essential ingredient for starting life, liquid water.
11:40The water forms when radioactive isotopes decay, giving off heat,
11:45melting the ice at the center of the comet.
11:47Think of this as our dirty snowball comet, hard frozen on the outside,
11:52temperature of minus 300 degrees Fahrenheit.
11:55The radioactive elements in the comet would be heating it up from the center,
11:58and this is what I'm going to simulate by putting it in a microwave.
12:01These are radioactive elements that are in the middle of the comet,
12:08and they release energy that begins to heat the comet from the inside.
12:13And let's see what's happened now with the inside heated by radioactive heat sources in the comet,
12:23and in this case we find the interior all melted and gooey,
12:31and the outside, the crust is still intact and frozen and cold.
12:35The gooey liquid interior of the comet, which is heated by radioactive heat sources,
12:43its chock-a-block with organic building blocks of life and a lot of liquid water as well,
12:49I think life originated in this gooey pool in the middle of a comet.
12:53In 2005, NASA engineers choose the comet Tempel 1 for a daring mission.
13:08They plan to smash a probe into the comet, exposing the inner core.
13:15The results of the mission could prove Wickram Singha's theory.
13:19This mission will test the engineers' abilities to the limit.
13:25The 820-pound payload will have to travel across space to intercept a comet traveling at 10 times the speed of a bullet.
13:38After six years of meticulous planning, finally on January 12, 2005,
13:43the Delta rocket carrying the Deep Impact Probe launches into space.
13:52After a 268,000-mile journey, the impactor, about the size of a school desk,
13:59separates from the mothership and hurdles toward the comet.
14:03It scores a direct hit.
14:13These images from space and Earth-based telescopes show the moment of impact.
14:22For the first time, the secrets of what lies inside a comet are exposed.
14:27From a lofty perch in space, the Spitzer Infrared Space Telescope analyzes the unique signals given off by the compounds contained in the plume of comet dust.
14:46An amazing array of ice and fine dust particles are seen.
14:53But to everyone's surprise, the data also shows that the comet contains clay, the same kind of clay, that can be found on Earth.
15:04And it's thought the only way to make clay is with liquid water.
15:13Vikram Singha believes that this is proof that at some point in time, Temple 1 did have a gooey liquid water interior.
15:22With liquid water and organic molecules, comets could be incubators for life.
15:28Comets like Temple 1 could be packed with microorganisms ready to seed life throughout the galaxy.
15:37We here on the Earth are connected to a much, much bigger cosmos.
15:41Life on the Earth is part of a connected chain of being that extends to the remotest corners of the galaxy,
15:49maybe to the remotest corners of the universe.
15:52We have our cousins out there.
15:53But whether life began inside a comet or on the Earth, what is still completely unknown is how it happened.
16:04How non-living organic molecules combine to create the first living thing.
16:10This big birth is one of the big unanswered questions in science.
16:15The ancients used to believe that life could emerge spontaneously.
16:18A frog could emerge from stagnant water or flies from rotten food.
16:26In the 19th century, Charles Darwin proposed that perhaps life emerged only once, many millions of years ago.
16:35He suggested that this big birth then led to all life today through a process of evolution.
16:42Starting with the simplest possible life form, more and more complex creatures evolve.
16:51As each new species emerges, it forms a new branch on the tree of life.
16:57And working backward in time, we can see our ancestors.
17:01Scientists propose that all life on Earth is descended from a single microscopic organism.
17:07What's known as the last common ancestor.
17:12Understanding this ancient microorganism will help scientists uncover the secrets of the big birth.
17:19But how can you unpick over 4 billion years of evolution?
17:25A good place to start is with fossils.
17:27Martin van Cranendonck is a geologist with the good fortune to live in Australia, home to some of the oldest rocks in the world.
17:41And among these ancient rocks, van Cranendonck claims to have found fossil remains of an unusual organism that lived 3.5 billion years ago.
17:51These are our great-great-great-great-great-great-great-great-great-grandfathers and grandmothers.
18:00These are fossil stromatolites, about 3.5 billion years old.
18:05And they were deposited on the shoreline of an ancient ocean.
18:09They're the oldest evidence for life on Earth.
18:12Stromatolites are rock-like build-ups of microbial mats clumped together in the ancient seawater.
18:18And they were composed of microbes that colonized the ancient seafloor on top of just wave-rippled sandstone.
18:27Their fossilized remains now show that life was already well underway 3.5 billion years ago.
18:35But what was it like?
18:37Well, after billions of years, the sea has changed, but modern stromatolites are still alive today.
18:44Von Cranendonck travels 600 miles across the Australian outback, here to Shark Bay.
18:52These are some of the largest stromatolites in the world, and they grow up to about a meter high.
18:58The stromatolite domes are formed by communities of microorganisms like bacteria and algae.
19:04They bind together with fine sediment to form layer upon layer of rock.
19:11Living on the mounds, the microorganisms carry out a process called photosynthesis.
19:17Using energy from sunlight, they turn carbon dioxide and water into energy, and in the process, they give off oxygen.
19:24Before bacteria like these evolved, there was little to no oxygen in the atmosphere.
19:33But luckily for us, these tiny microbes did a great job kicking off the process which over billions of years created the oxygen in the atmosphere that we rely on today to breathe.
19:44They are really the first great polluters, and that's in effect what made the whole atmosphere of planet Earth change from a carbon dioxide rich atmosphere to this oxygen rich atmosphere.
19:59It's these little beasts that made that change about two and a half billion years ago.
20:03But even though stromatolites date back at least three and a half billion years, scientists believe that they are still not the first step in the creation of life.
20:16To find that, we have to travel back even further in time.
20:22So far, there is no fossil record for this ancient period, but one scientist thinks she can discover what these first forms of life were like.
20:31It's a quest that will take her to one of the most remote places on Earth.
20:41The quest to understand the birth of life has sent scientists looking for clues around the world and out to the far reaches of the universe.
20:51They want to understand the moment when inert chemicals came together to produce the first living thing.
20:58One approach is to unravel four billion years of evolution, to travel back in time to uncover the oldest and simplest forms of life.
21:10And the Holy Grail is a theoretical four billion year old microorganism known as the last common ancestor.
21:18This tiny cell gave rise to all life on the planet and close relatives may still be alive today.
21:28There are estimated to be three billion separate species of microorganism on Earth, but less than one percent has so far been discovered.
21:37Hunting them down is NASA biologist, Dr. Lynn Rothschild.
21:41All you have to do is look under a microscope, and they are so incredibly cool.
21:47When I was eight years old, I looked through a microscope and I just fell in love.
21:52I realized that they are absolutely at a crucial step to study evolution, and so that's the direction I went with my own research.
21:59So I get to have fun and get to study something important.
22:05Rothschild is traveling 14,000 feet above sea level to the Altiplano in southern Bolivia.
22:13It's a hostile landscape where temperatures regularly drop to minus four degrees Fahrenheit.
22:19It also has some of the highest recorded levels of ultraviolet radiation on Earth.
22:24But it could be the perfect place to find a close relation of the microbe that gave rise to all life on Earth, the last common ancestor.
22:39Coming up into the living Andes here seems like the last place on Earth we'd go to look for early life.
22:45But we found organisms up here that are probably like the earliest organisms on Earth.
22:50Hey, maybe we're even going to find ones that are similar to the last common ancestor of all of us.
22:59Rothschild scours the Earth, looking for microbes living in extreme conditions.
23:05It turns out that these microorganisms, called extremophiles, may be closely related to the most ancient forms of life.
23:13You have to really go to unusual environments to find ecosystems that are just microbial.
23:19I hope that those organisms prove to be extremely deep branch, in other words, organisms that seem to be much closer to our last common ancestor than you and me.
23:31Next stop for Rothschild is a landscape of boiling mud.
23:36Superheated steam, warmed by shallow bodies of magma, shoots out of the ground.
23:41Hot geysers like this would have been present on early Earth, so Rothschild hopes to find life in these extreme conditions.
23:51The earliest common life form that we're all descended from lived in very high temperatures.
23:58Rothschild works meticulously, logging the exact temperature and position of each sample she takes.
24:04A great challenge for scientists trying to understand how life began is that even the most basic microorganisms alive today are still incredibly complex.
24:16When looked at on a microscopic scale, the intricate complexity of a cell is clear.
24:22From its ability to reproduce, to the way it converts energy, every process in the cell is carried out by an extraordinary interplay of complex organic molecules.
24:35But the ancient microorganisms that Rothschild is tracking down in Bolivia could give us clues to the nature of the first organisms.
24:43As the sun dips below the horizon, the temperature plummets.
24:51Rothschild takes refuge from the harsh environment where these modern cousins thrive.
24:57Overnight, the temperature drops well below zero.
25:03Next morning, the vehicle won't start.
25:06Dr. Rothschild also feels the effects of the thin air, 14,000 feet above sea level.
25:20It's not much fun for us when we drop our oxygen levels just a few percent, but on the early Earth there was no free oxygen whatsoever.
25:28So just to time travel back just a little bit is a huge price to pay for us humans.
25:33Rothschild's next hunting ground is the Laguna Colorado.
25:39Its red color gives a clue about the very unusual type of microbe she hopes to find.
25:45This part of Bolivia boasts one of the highest UV counts of anywhere in the world.
25:50The thin atmosphere at this high altitude only partially blocks the sun's radiation,
25:56making living conditions here closer to those of the Earth 4 billion years ago.
26:00When life first arose, the level was incredibly high, vastly higher than we see today.
26:08And so by coming up here, even though we're not able to simulate the early Earth,
26:12because of course we couldn't live under those conditions,
26:15at least we can time travel a step backwards and get some idea what it would have been like for organisms in the past.
26:21Dr. Rothschild measures the levels of UV radiation.
26:33These readings are amazing.
26:36This is the middle of winter and already we've got extremely high UV readings,
26:41and I bet they're going to be even higher by noon.
26:43It's just amazing.
26:44Readings here can reach twice the average level of a California beach.
26:49And just as our skin is in danger from too much UV when we lie in the sun,
26:54the microbes that live here in Bolivia are at constant risk.
26:59Rothschild carries out a simple experiment to find out just what they are up against.
27:04What I'm doing now is looking at the effect of ultraviolet radiation from the sun on naked DNA.
27:10The naked DNA is a solution containing DNA molecules stripped of any protection from the cell that would normally surround it.
27:21And then what I'm going to do is seal it up and leave it out in the sun for a few hours.
27:27After just two hours of UV bombardment, the DNA molecules show severe damage.
27:33Levels of UV on the early Earth would have been around a hundred times higher.
27:37Many scientists think that our last common ancestor had to live in the dark depths of the ocean or buried under the ground for protection.
27:47But the microbes here manage to survive.
27:50Their red pigment helps protect their DNA.
27:56Just like we suntan in the summer to protect ourselves, these organisms produce red pigment.
28:01But even though we know that UV radiation is very damaging to the DNA in all living organisms, there's also a flip side.
28:10UV radiation may have helped to drive evolution.
28:14It might even have had a role in kick-starting the big birth and the evolution of the last common ancestor.
28:19Ultraviolet radiation produces mutations.
28:24Now, mutations aren't all bad. Without mutations, we wouldn't have evolution.
28:29You need to have change in the genetic material to have change in the organisms.
28:34And our world, of course, would be very different if nothing had ever changed.
28:39We wouldn't be here.
28:40Dr. Rothschild's study of these microbes will help scientists understand how the first organisms survived the hostile conditions on the early Earth.
28:51And give a clearer picture of what our last common ancestor was like.
28:56But another great mystery remains.
28:59How did the last common ancestor form?
29:02What is the link between the building blocks of life and the big birth?
29:06It turns out that some of the answers to that great puzzle may emerge from an extraordinary place in the depths of the ocean.
29:17The question of how life began has troubled scientists for centuries.
29:24Darwin's theory of evolution explains how species evolved, but we still do not understand how the first living thing was created, how evolution began.
29:34Creating life had been the stuff of science fiction.
29:41It's alive! It's alive!
29:49Then, in 1953, a bold experiment began the modern scientific investigation into the origin of life.
29:57Stanley Miller tries to recreate the conditions of early Earth when scientists think life began.
30:06John Chalmers was an associate of Miller and now works in his lab.
30:11Stanley's was the first one to really have a research program directed towards the origin of life.
30:16It changed the ideas about the origin of life from mere speculation to a research program.
30:26Since Darwin's time, a lot has been learned about what the planet was like 4 billion years ago.
30:32It was an extraordinarily violent time.
30:34The Earth had only just formed and was continually bombarded by meteors, asteroids and comets.
30:42And the atmosphere was very different to what we're used to today.
30:49Stanley Miller's experiment recreates these conditions in the lab.
30:53The flasks contained what Miller believed were the key components of the Earth's early atmosphere.
31:01Methane, ammonia and hydrogen.
31:04The warm water represents the early ocean.
31:08But the key component was a Frankenstein-like bolt of lightning.
31:12A simulation of the electric storms that would have raged on the young planet.
31:19Miller started the experiment.
31:21And the next day when he returned to the lab, he was in for a shock.
31:29The liquid in one of the jars had changed color.
31:33And when he analyzed the substance, he found something remarkable.
31:37It was packed with chemicals called amino acids.
31:40What biologists and chemists call the building blocks of life.
31:45Of course, they're very important because all terrestrial life is made up of amino acids.
31:51Miller's experiment showed how simple molecules could be transformed into the building blocks of life.
31:59But these building blocks are still a long way from any kind of life.
32:04How do these so-called building blocks create life?
32:10One clue was to come from a very special package that was delivered to the Earth from space.
32:16In September 1969, the residents of Murchison in southern Australia were startled by a loud bang.
32:25A 200-pound meteorite fell into their village, showering it with rock.
32:35These small pieces of space rock have been the object of intense study ever since.
32:40Dave Diemer at the University of California, Santa Cruz, managed to get his hands on a sample.
32:48There was a flash of light in the sky and a rolling thunder and a few minutes later, the stones of the meteorite just fell all over Murchison, Australia.
32:58And there's a strange aroma in the air.
33:00Dave Diemer extracts a compound from his small piece of the meteorite, which has the same aroma.
33:07So when I'm smelling this, I'm smelling an aroma that's 4.57 billion years old.
33:14That's the age of the solar system.
33:16Now, it's the oldest aroma on Earth, much older than the Earth's surface by about half a billion years.
33:22And I'm smelling it. It's got a kind of a old cigar butt smell or dirty sock smell.
33:27The smell gave Professor Diemer a clue that the liquid he had extracted from the meteorite was packed with organic chemicals.
33:38When he took this extract and put it under the microscope, he saw something extraordinary.
33:43We see beautiful little glowing vesicles that look just about the right size for a bacterial cell or larger cells.
33:52The extract from the meteorite contained molecules that were able to form tiny bubbles or vesicles.
34:01These vesicles looked just like the outer membrane of a small microbe.
34:06Some of the compounds were able to form membranous structures, beautiful little cell-like compartments.
34:12And we proposed then that this would be a way for the first cell membranes to have come about on the early Earth from these sorts of molecules.
34:20Perhaps these compounds, delivered from space, were the first steps on the road to life.
34:27But in order to form membranes, these molecules needed to have been in fresh water at just the right concentration.
34:34One idea of how this could happen is that they fell near a geyser in a warm volcanic pool.
34:42As the water droplets evaporate, the molecules start to become more concentrated and form tiny vesicles.
34:52Perhaps these self-assembling cell membranes, delivered from space, were the first steps on the road to life.
34:59The transformation of non-living chemicals into the first living cell.
35:07So I don't have any trouble imagining that this would be a common process and this formation of compartments would have been the first step towards cellular life.
35:16But a simple bubble-like membrane is still a long way from being alive.
35:22Scientists still have to figure out how all the complex components that make up a cell came together to create the big birth.
35:29In 1977, a team from the Woods Hole Oceanographic Institution were looking for signs of volcanic activity on the sea floor, 8,000 feet under the surface of the ocean.
35:42Alongside these hydrothermal vents, they also found an incredible undersea world.
36:02Cut off from the light of the sun, it was thriving with species of plants and animals that had never been seen before.
36:14Until that moment, many scientists thought that all living ecosystems depended on photosynthesis.
36:21But here was a unique environment completely cut off from sunlight.
36:25This strange underwater world captivated Carnegie Institute researcher Dr. Robert Hazen.
36:33Imagine how exciting it was to descend in the submarine under the black depths of the ocean where people thought there was nothing.
36:40And they find these hydrothermal vents, these places where volcanic fluids are pouring out of the ocean floor.
36:46And not only that, because of all that energy, chemical energy, heat, there's living things, there's ecosystems, life abounds, microbes and tube worms and clams and all sorts of strange crabs and other things.
37:01After searching at these crushing depths, they found unexpected chimney-type stacks emitting plumes of scalding hot water.
37:08He had a hunch that these hot vents could be producing some interesting chemistry.
37:15Perhaps they could have produced the organic building blocks of life.
37:19He set up an experiment to find out.
37:26It's easy to do these experiments.
37:28You see, you just take a little bit of mineral, a little bit of chemicals, you put them in a gold tube and seal it up.
37:32You put that tube at high temperature and high pressure just for a few hours.
37:37Open it up.
37:39There's all this stuff inside.
37:41And the stuff he found turned out to be far more exciting than he'd ever imagined.
37:47When we did these experiments, we thought we'd find nothing really very interesting, just a few simple molecules that we could analyze and maybe write a little paper on.
37:54We were wrong.
37:55This stuff had the strongest aromatic smell.
37:58At lower temperature, it was like molasses.
38:01And at a little bit higher temperature, 350 degrees or so, it smelled exactly like Jack Daniels whiskey.
38:07People would come by the lab and say, boy, you guys must be having fun.
38:10What are you doing?
38:12We were making the stuff of life.
38:14This strange aroma gave Hazen the clue that he too had created organic molecules.
38:20Once again, these molecules assembled into tiny membrane-like vesicles.
38:27They were behaving much like the molecules extracted from the Murchison meteorite.
38:32So Hazen had discovered that it might be possible to create these cell-like membranes close to the deep sea vents.
38:39But other researchers believe that this strange underwater world was capable of providing more than just a cell membrane.
38:47They believe that these warm vents were where all life's component parts came together.
38:54They claim the big birth happened here, at the bottom of a primordial ocean.
38:59In order for the big birth to occur, scientists believe that certain essential elements had to work together.
39:07For example, life needed a container, which came in the form of a membrane.
39:12It needed some way to reproduce.
39:14Today, this process is achieved through an extraordinary chain of organic molecules, DNA.
39:25Life also needed an engine.
39:28A chemical process called metabolism that converts fuel into usable energy.
39:34According to Dr. Michael Russell at NASA's Jet Propulsion Laboratory, it's metabolism that came first.
39:40Life has a job to do, basically.
39:43I could put it like this. You could have a modern car with an engine and a computer inside, but if you take the computer out, the car will still work.
39:52But if you take the engine out and just leave the computer, it won't.
39:56The computer is the kind of regulator, but the engine is what's really important.
39:59So that's why we think there has to be an engine first and that engine is metabolism.
40:03Today, the engine of metabolism that powers every living thing is an extremely complex chemical reaction.
40:12But intriguingly, Russell thinks we all have traces of the first and simplest metabolic reaction buried within our cells, like living fossils, that point to where life began.
40:25We can trace the kind of chemicals in the early Earth and see them even to this day.
40:32So, for example, there are iron sulfides in our skin, for example, and that's the little bit of rock that, to our mind, reminds us where we all come from.
40:41And according to Russell, this is where we come from, deep-sea vents made largely of iron sulfide.
40:50He believes that this and other compounds kick-started metabolism, acting as a catalyst to enable a reaction between hydrogen gas streaming out of the vents and carbon dioxide dissolved in the water.
41:04But eventually, this simple reaction evolved to become the complex chemical engine metabolism.
41:13And eventually, the metabolism required DNA because it did need a regulator, it did need a computer.
41:19But to start with, we just needed the engine.
41:22At some point, the metabolic engines acquired some bodywork, a membrane.
41:27Russell's theory gives one idea of how a simple chemical reaction could have driven the creation of more and more complex organic molecules.
41:41And eventually, created the first living cell and all life on the planet.
41:47There are still many gaps, but slowly, the clues to the origin of life are beginning to emerge.
41:53But now, a scientist claims that he might be able to put all these clues together using the latest laboratory techniques.
42:01He hopes to start life from scratch, something that hasn't happened on this planet for the past 4 billion years.
42:08Scientists are striving to answer the great question of how life began.
42:24It's a quest that has taken them to the remotest corners of the globe and deep into the inner workings of the cell.
42:31But as one group of researchers look back 4 billion years to the big birth, another group of scientists is looking to the future.
42:42Around 4 billion years after nature first created life, scientists are now able to redesign it.
42:49The key to this extraordinary power is their understanding of one extraordinary chain of molecules.
42:59DNA.
43:01DNA is made up of 4 simple base molecules.
43:04Adenine, guanine, cytosine and thymine.
43:08The arrangement of these 4 molecules stores the information needed to create life.
43:12It's this natural technological innovation that's at the heart of all life on Earth today.
43:19And Tom Knight, a computer expert at MIT, wants to reprogram DNA to make new kinds of life.
43:26Fundamentally, there is one technology of life right now.
43:31And that technology perhaps was invented billions of years ago.
43:38And all we are doing is changing little bits and pieces of that technology.
43:45For thousands of years, mankind has harnessed nature, rearing livestock and growing crops.
43:52Selective breeding has improved yields and created higher quality.
43:56But now, bioengineers want to take a step further.
44:01Instead of just improving nature's original designs, some want to re-engineer life.
44:08Creating so-called Life 2.0.
44:11We can now think about growing things which are not food.
44:17We could think about growing things like nanotechnology level substrates for electronic circuits.
44:23I have a student who is looking at placing atoms precisely in patterned arrays on silicon surfaces.
44:34These new life forms might be able to manufacture products for us cheaply and easily.
44:40It's a little bit like going to the store and buying a cell phone.
44:44And what comes in the package with the cell phone is not just the cell phone, but also the factory which makes more cell phones.
44:50Re-engineering biology will bring a new era of exciting possibilities.
44:56But it will also bring new risks and responsibilities.
45:00And this is the shocking result.
45:02Any new biological factory released into the environment could have unforeseen consequences.
45:09A living factory with the ability to reproduce itself could be unstoppable.
45:13This town is in danger.
45:14But for the moment at least, this nightmare scenario is far away because these new organisms are a long way from leaving the lab.
45:25As well as hoping to create new forms of life, bioengineering is now giving science a chance to explain the mystery of the big birth.
45:33Instead of having to attack the problem from the bottom up using basic chemistry or from the top down by unraveling evolution, scientists can now use the technology of bioengineering to try and put the building blocks of life together themselves and create a living cell.
45:51Jack Shostak at the Harvard Medical School is a leader in the field.
45:57Jack Shostak at Harvard Medical School is a leader in the field.
45:58Jack Shostak at Harvard Medical School is a leader in the field.
46:00Jack Shostak We're making the assumption that okay, someday, people will figure out how you make the building blocks you need.
46:03What happens if you have the building blocks?
46:07How do you put them together?
46:09How do you organize them so that they start acting like a cell?
46:13Shostak and his team at the Harvard Medical School have set themselves the task of building a living system in the lab.
46:20Well, we'd like to understand that transition from the chemistry of making molecules to
46:29the way that these molecules work together to give us life.
46:34So we would like to build a simple living system as a way of trying to understand that transition.
46:41Scientists believe life evolved over millions of years.
46:45Shostak is hoping to use the latest bioengineering techniques to do it in considerably less time.
46:53We want to make things go fast, as fast as possible, so we're making the building blocks ourselves
46:59and putting them together in just the right environment.
47:02We would like to get everything going in the timescale of a few years, which is speeding things up by a factor of, say, 100 million.
47:12Shostak hopes to create a working cell from simple building blocks.
47:18The only way he can do this is by boiling down a cell to its simplest possible components.
47:24One of the things that's made the origin of life very hard to think about for decades
47:29is the fact that all of the life we're used to seeing every day is so complicated.
47:36A big challenge is to create a simpler version of the complex DNA molecule.
47:41Shostak believes the answer is RNA.
47:45RNA is also made of four base molecules.
47:48But instead of being wound into a double helix, RNA has only one strand.
47:53Now, if you go back to thinking about really early simple cells, you could store some information in just RNA.
48:03You don't need to have DNA.
48:06Shostak's goal is to create a simple self-replicating RNA molecule.
48:11This, in theory, would eventually form a simple cell capable of duplicating itself.
48:17If successful, he may be able to start a process of evolution.
48:22We're interested in the beginnings of life, the transition from chemistry to the beginnings of biological behavior.
48:29And to me, the important thing that we have to think of in that transition is the beginning of evolution.
48:37And once evolution can begin, more and more complex cells will be created by the process of natural selection.
48:45Eventually, Shostak hopes to be able to evolve a simple self-supporting, self-replicating biological system.
48:53Some might call it life.
48:56Shostak's work might one day connect the dots between the building blocks of life and the last common ancestor.
49:04And show how inert chemicals can combine to create life.
49:11If he succeeds, it will be the crowning moment of over a century of research by some of science's greatest minds.
49:19Finally, we might solve the great riddle of how life began on our planet.
49:26We'll see you next time.
49:27We'll see you next time.
49:28Bye.