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Hunt for the Oldest DNA | Full Documentary | NOVA | PBS
c2ppreiB1PQ • 2024-02-22
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Kind: captions Language: en [Music] for centuries the best Clues to ancient life have come from fossils but now a new window on the past is opening how can we travel back in time is that time machine yes it's DNA it's ancient DNA these are fragile molecules that fall apart outside the body how long can DNA survive with ancient DNA we're trying to go back in time but time is the enemy a dramatic breakthrough is transporting us millions of years back into the past to before the last ice age revealing surprising creatures that thrived when our planet was Far warmer than it is today could ancient genes from this Lost World help us adapt to a changing [Music] planet we are stealing genetic secrets of the past so we can rescue the future go behind the scenes on the hunt for the oldest DNA right now on [Music] Nova buried beneath Greenland's ice sheet are the remains of a living world that ended when the ice age began over 2 million years years ago one scientist is on a quest to reveal that lost world with ancient DNA when I look at this place I see one huge cold storage room for ancient DNA I spent my life trying to find older and older DNA and this is the limit of the possible and maybe it's impossible what we are trying to recover is DNA millions of years older than any DNA ever recovered so we're trying to reach back before the last ice AG once fossils were our only hope of shedding light on life in the distant past but ever since scientists first recovered DNA from an extinct animal 40 years ago fossil Hunters have been sharing the stage with genan Hunters we've peered into a fascinating world of extinct species Ice Age beasts even our Neanderthal cousins when I look back in time the sharpest tool I have is DNA the genes of long dead plants and animals this is a far more detailed record of the past than the fossils alone can ever give us but the older DNA gets the fainter the signal the moment a living thing dies its DNA starts falling AP part of course we are never going to stop wondering exactly how far back can we go what is the limit of DNA preservation you know what people mean when they say Mission Impossible right they actually mean it might be possible no one has ever succeeded in getting DNA older than 1 million years but our tools are getting better and as the technology gets more powerful these scientists are chasing a new discovery to everyone's surprise the secret to smashing the limit could be lying right beneath our feet now we're on the verge of recovering genetic traces of a lost world from before the Ice Age this ancient DNA forged in a hotter climate might even help us survive our own warming world [Music] when I was in school if you said to my teacher someday es will be a scientist they would have laughed I mean I would have laughed too I was a rebel a troublemaker I wasn't good at the typical things that people connect to being a scientist I was a school failure that's the truth but I think I have one capability which has proven super valuable I have a very good imagination I used to think I was born too late when I realized there's no Frontiers left everything is mapped but there is a frontier our Frontier is the Deep past that is where we can still be [Music] explorers in Iceland Esa Willers lv's team is pulling mud from the bottom of frozen lakes mud laced with DNA from a long gone [Music] World DNA is a a blueprint right it's the code who makes you who you are different individuals have different DNA codes different spe at different DNA codes so it means if you can pull out a piece of the DNA code you can actually map it to all known DNA codes all known Blueprints and then you can identify well what organism are we talking about here on this Expedition esa's team is hunting for DNA from before the Viking settled Iceland about 12200 years ago 1200 years is nothing in ancient DNA research especially in the Arctic where it's cold still at a certain point DNA becomes too difficult to read so there is a limit and I would say I always been obsessed with this limit to push this limit how far can we go I still haven't got an answer to that question but I'm sure it's further than what we think so what is the limit back in the '90s some scientists got a little carried away Jurassic Park was not a documentary the early days of ancient DNA were a bit of a disaster unless you're in PR in which case it was fantastic there was a whole bunch of what we now know is complete nonsense that was published with just abandon just excitement and enthusiasm other than actual science I mean everybody wants there to be dinosaur DNA and so somebody who says hey I got this really well-preserved dinosaur and guess what there's DNA in it of course the media are going to be super excited about [Music] this and Hollywood couldn't [Music] resist so let's reconstruct Jurassic Park scientists go somewhere hot because Amber forms in hot places and they find a really beautiful piece of Amber inside of which they can see this fantastic insect that looks perfectly preserved they take a big needle and they stick it into the insect and they draw out blood presumably from a dinosaur and then they take that blood to the lab and they do some magic that for some reason involves frogs even though we already knew at the time that birds were the closest living ancestor of dinosaurs and then more magic happens and uh dinosaurs are back to life but we now know a lot more about DNA than we used to and everything we know tells us no question about it that this molecule just doesn't stick around for millions and millions of years dinosaurs have been extinct for more than 65 million years we will never get dinosaur DNA Jurassic Park is not going to happen I'm sorry getting DNA out of things that are alive is easy this is because modern DNA DNA from living organisms is in fantastic condition long strands of DNA if you can think of it kind of as party streamers ancient DNA is more like confetti the reason that modern DNA party streamers get chopped up into the confetti that is ancient DNA it's because of random processes that happen outside the body mostly things like UV radiation from the sun when we walk outside UV hits our skin and it gets into our cells and it damages our DNA but when we're alive we have proofreading enzymes that will come along and fix those damages otherwise we would get cancer every time we walked outside but proofreading and fixing DNA this is this is an energy requiring process and after you're dead there is no more energy with ancient DNA it's always been a needle in the Hast stack problem this is a fragile molecule so even when we first understood that DNA could stick around after death the question was how much and where early on we thought only in soft tissue so a human mummy or frozen mammoth in about 1990 we had the huge Insight that fossil bones and teeth could protect de like time capsules but well-preserved fossils are rare and fossils that contain DNA they're even rarer so in our field that's been one of the biggest challenges we're all chasing these precious time capsules [Music] three decades ago Esa was determined to join the hunt but the odds were against [Music] him in 1995 I was a biology student and I wanted to do my research on Ancient DNA but I had no fossiles I wasn't famous so nobody wanted to give me fossiles that was a bit of a problem you want to do ancient DNA but you have no fossiles I remember I was in my flat it was an awful day the rain was just coming down and leaves were falling from the trees and I saw this woman out walking her dog and she stops the dog squats takes a poop it's funny inspiration sometimes comes out of the strange times I'm looking at this miserable wet dog thinking well there's DNA in the dark so there's DNA in the dark poop right but will it survive we know there's DNA in the leaves but we also do know that these things will disappear after next rainfall the dark poop will disappear after a few years the leaves will be gone the question I asked myself what because what will happen to the DNA will that be gone to or will that be preserved in the soil because if it's preserved in the soil we don't need any fossiles problem solved so I remember I went into uh the coffee room in Department of zoology where all the professors were sitting you know having their lunch and I came with this idea saying well what about looking in in the soil for DNA of animals and plants and they were laughing and my my supervisor turned around was head of the apartment saying I never heard anything as stupid in my life no one had ever thought to recover DNA from dirt why would it be there the idea is that DNA is it's kind of known to be such an unstable molecule in general if you're working in a molecular biology lab and you don't look after your DNA it's gone very fast so yeah was a completely crazy idea that it would even be found I mean that DNA enters the environment is obvious if an animal urinates or defecates but the DNA stays in the environment completely crazy so early on we didn't know how long ancient DNA could survive but there was a second really big hole in our understanding contamination ancient DNA getting mixed up with modern DNA but the trouble is that DNA is everywhere my DNA is now on this chair and on my hands and on my shirt and DNA is coming out of my mouth as I talk and there is microbial DNA absolutely everywhere so when people were sequencing these bones they were getting DNA and they were saying wow there's DNA in these bones it must be dinosaur DNA I think there was some dinosaur DNA that was published that they were really excited about because it closely matched a bird Well turns out the field excavation team was having a chicken dinner one night in those early days when I was still a student we were all struggling with the problem of contamination which was the big downfall of the dinosaur DNA guys of the '90s and I decided Well somehow we're going to solve that problem I was working on this with an another student H Hansen so we had this room that were basically our clean laboratory but we had a problem with a M contamination and in the end we became so desperate we decided okay we will basically clean the entire room down with very strong bleach we knew well it wasn't really allowed and we didn't have money for G ass [Music] masks anas got got dizzy and threw [Music] up and the security God was coming say what the is going on here it's smelling like a swimming pool in the entire building and Monday morning we were had to stand in front of the professor and the lab director and they were Furious right I mean what are you guys doing I mean do you know this is totally legal but the good news was even though we we got all this heat the fungi contamination were gone finally Esa had a mold-free lab he first tried getting DNA out of 2,000-year-old ice we got ice CA from Greenland and we showed we could recover ancient fungi DNA trapped in the ice without contamination and that was big so then we knew we were ready to move to the next step searching for DNA in the dirt so I really believed in this idea of environmental DNA or dirt DNA and more than that that it could survive in the environment as ancient DNA but I had to prove it so I set out to retrieve ancient DNA from the dirt and at that point no one had done that Esa was searching for DNA from the Ice Age which ended 12,000 years ago it kept our planet in a frigid grip for about 2 and 1 half million years the Ice Age it's an amazing period it's the time of the big mammals you have giant wolves giant beavers Mammoth mastodons right so I thought imagine how much poop and urine these big mammals have been producing over time right that is in the soil in the surrounding Frozen in time in the Arctic so my idea was to bring back that Ice Age World by retrieving DNA directly from the permafrost and that per Frost I got from Siberia so while everyone else was looking for DNA in fossile bone and teeth and discovering one species at a time I was looking in the dirt for everything it's one thing to recover ancient DNA but it's a far more daunting challenge to read those tiny fragments of genetic confetti that is to decode what kind of ancient life they come from the shorter the fragment the harder it is to identify a genome is like a twisted ladder so if you think of a long lad every rung is a base pair and a base is a single molecule a t g and C a human genome is incredibly long it has 3 billion base pairs so that's 3 billion rungs on the ladder that's a big number but when we're working with ancient DNA we're working with short pieces pieces just a few rungs long and we have to hope that those little pieces contain enough unique information that we can match them to known DNA Su of esa's Siberian permafrost was 400,000 years old if he could identify species from ancient DNA Frozen inside it he would set a new record so it's Christmas Eve and I'm I'm sitting alone in the lab everybody have already gone home right for for Christmas and I'm I'm basically checking the DNA sequences that we got out of the dirt I'm comparing those to all known DNA sequences in the world and when I see the results the hairs on my back are just Rising it was bang woly Mammoth it was bang bison it was bang reindeer it was bang hair it was bang bang bang different types of plants it worked better than I could even have imagine Esa had matched the ancient DNA in his Siberian dirt to known species whose genetic sequences were collected in a vast catalog and sure enough he found dozens of matches including extinct species ese was the first to show that enough DNA can survive in the dirt to paint a picture of the past still a student he just sparked a new field of science ancient environmental DNA the reason the technique of environmental DNA works is that DNA is everywhere it is raining DNA the very problem we had with DNA contaminating samples that DNA is falling off of me and coming out of my mouth and floating in the air around me that is exactly the opportunity we have with environmental DNA so I realized it's not the scarcity of DNA that is limiting us environmental DNA is everywhere the limit is time and this is really when I started thinking well how far back in time can we really push [Music] this so today we are in the hallene that's about the last 12,000 years before that it was the plene a period of lots of ice ages more than 20 lasted about 2 and 1/2 million years and before that was the pene when it was much warmer than the pine yeah it was a really weird place you would not recognize that world when you go back 3 million years you're in a way warmer climate Earth was just hotter and it had been that way for a very long time since before the extinction of the dinosaur 65 million years ago I'm a vertebrate paleontologist I study the animals that live in the Arctic before the Ice Age mammals of the pine Arctic the reality is we don't know very much the time before the Ice Age began the pene it's kind of a lost world we don't have full skeletons of any p mammals we just have fragments shards of bone evidence of maybe 13 species I still have so many questions for a paleontologist like me it's really frustrating so where fossils are lacking could DNA help us could genetic traces really endure for millions of years everything we knew about DNA had told us that was impossible the oldest DNA is the coldest DNA DNA is fragile so it falls apart over time but cold slows that process down no one has ever succeeded in getting DNA older than 1 million years but our tool are getting better so I think the limits might change 20 years ago recovering 400,000 yearold DNA from Siberian permafrost was an impressive leap back in time the student was suddenly a professor the youngest in Denmark but's Quest had just begun so I just happened to get this invit ation from a group of geologists to go up to Northeastern Greenland and uh this is a remarkable place I mean there you have something called the cup Copenhagen formation and it's a super dry and a super cold place naturally I thought Northern Greenland would hold the answer if really old DNA is going to be preserved anywhere it's here [Music] Northeastern Greenland it's one of the most hostile places on Earth extremely cold but even more important this is an Arctic desert it was too dry for glaciers to form no glaciers to grind away the landscape the sediments up there are perfectly preserved served and cap Copenhagen you're literally walking on dirt from before the Ice Age it's incredible this place that is almost Barren ground today right in the sediments we discovered chunks of trees of wood that are 3 million years old but is still preserved there I mean you can basically take them up and use them as fuel in your campfire so this told me two things first C Copenhagen must have looked very different in the past and secondly this must be among the best places in the world for long-term preservation of DNA this gave me an idea a naughty [Music] idea what if we could just stick in the dirt dirt and recover DNA millions of years old if your goal is to get the oldest sample then you go where that oldest sample is likely to be it reckons back to the age of exploration right I mean think about my my kids are in fourth grade or so they're learning about the explorers that went around the world and this is kind of I think how Esa sees himself a bit he's like oh you know what there's an Arctic desert I'm going to go there and I'm going to get DNA from that and he will because he's Esa and that's how Esa Works in 2005 I published this review paper where we basically claimed well ancient DNA cannot survive for more than 1 million years that's the absolute limit but in the back of my head I was still wondering is that really true right could DNA survive longer than 1 million years in a place like the cap Goen ha information so on that same Expedition I thought hey I mean we're here why not sample the sediments you never know we just might be able to find DNA I remember it was pretty miserable up there we working in a freezing Arctic desert or it rained anyway still we caught into the frozen ground and I got my crazy samples so I took the camon samples back to my lab in Copenhagen and uh to be honest this was the beginning of a very frustrating project those Greenland samples would tease and torment Esa and his team for the next 15 years in the early days Astrid Schmidt was a doctoral student in esa's lab when Esa offered her the Greenland samples she jumped on them at that time is was a a star in the scientific community and I was inspired by is's enthusiasm we had a hypothesis that if the environment had been kept cold and the temperatures had not been moving up and down and fluctuated then we would have had at least a possibility of finding ancient DNA so we were being uh optimistic knowing it was a long shot but also knowing that we could get groundbreaking results from this and there was DNA in the samples we could see it but it was super degraded it's not enough to see that your sample is contain ancient DNA you have to be able to identify that DNA and to know what forms of life it came from to to do that the fragments need to be long enough you need a certain number of base pairs in a fragment you need enough rungs on your ladder when astd started scientists needed at least 100 base pairs we did everything we could with the technology that existed but we just couldn't overcome the central problem the Greenland DNA was just too old the fragments were too short it was very frustrating the DNA after 1 million year was just total garbage with you can say the technology in hand at the time the DNA was completely unreadable well astd uh was one of many people in my lab that tried the cap Copenhagen samples and basically failed in retrospect I was probably not a very good supervisor right because I I kind of push for people to do these samples every time we had improvements of our mythology in a hope while this time they will work if that happened it would be a career booster but uh the risk associated with this project was huge right so it was failure after failure C Cen Hound project was um yeah a bit sensitive as opposed to if you decided to invest your time in this it was the case of having only so many years to be able to produce excellent research if you're not able to produce research because the technology doesn't allow it not because you're a bad researcher you still end up with nothing to show for it in 2013 I left research science and I I didn't pursue science um since then I took a big risk and I paid a price but again but the thing is just like with the police in esa's lab students began calling the Greenland samples cursed but Esa and his team kept returning to Greenland hoping to find DNA in better condition meanwhile four more students suffered under the curse failing to recover DNA long enough to identify they all changed careers but as they left new one stepped into their shoes so you you can imagine what I felt when this these samples landed on my table so I was a PhD student in es lab this was my last option also to succeed in a project that I was given as a PhD student I was coming to the final tries of of of actually making this a success back in the day we needed almost 100 base pair fragments to survive in a sample in order to retrieve any DNA whatsoever but the technology was changing and I had a student Migel who came to me with an idea I was immediately excited I thought yes this could work EXC migle suggested we use a powerful technique called shotgun sequencing shotgun sequencing itself was new but no one had ever used it on dirt DNA I don't know why in retrospect it seemed kind of obvious scared first ml proved that the shotgun technique could work on dirt DNA several thousand years old it really showed us that we could actually get ancient environmental DNA even from the very shortest greets that that were preserving in the samples and the obvious Next Step would actually be to take on the most challenging project of them all what we refer to as the curse the C Copenhagen formation in the early years of ancient DNA we had to decide which part of the genome to look at those are the giveaway parts of the genome that we call barcodes they reveal the identity of an organism we match those barcodes to our reference catalog but those barcode fragments had to be long enough we know that DNA fragments over 100 base Bears just don't survive millions of years even Frozen high up in the Arctic so shotgun sequencing was a revolution now instead of targeting a specific part of the genome with Precision like with a rifle we're using a shotgun a shotgun hits everything with the shotgun method we just see all the DNA we can find then we look for matches with every genome sequence for every organism that we know of it takes immense computing power billions of operations and only now our computers powerful enough to work with fragments down to 30 base pairs imagine shredding one piece all you have are short phrases not even sentences and you walk into the Library of Congress and you start looking for a match for each one of those phrases book by book by book there's another one piece in there somewhere but you need to work through millions of other books before you find the match and once you do your job is to reconstruct as many pages of that novel as you can so we were the first to use shotgun sequencing on dirt and when we did man it was powerful in science moments like this actually feels like magic I have no other way of putting it it was just like that Christmas Eve 25 years ago as if by Magic we were seeing the genetic signatures of these plants and animals appear bang bang bang but it's different this time now there's hundreds fleas lemings Arctic hair geese Caribou a whole forest ecosystem large po Willow Spruce Ash cedar trees we're looking at a long list of organisms from a place that today is an Arctic desert [Music] esa's team had recovered the genetic Fingerprints of a lost world nine land and sea animals from horseshoe crabs to Big mammals over a 100 plants from mosses to forest trees and nearly 2,000 other organisms including bacteria and Plankton some of them extinct and many of them never detected in the the Arctic but this incredible breakthrough created another problem if you're claiming to have recovered the world's oldest DNA you'd better be very sure about the date we knew we were going to get hammered extraordinary claims demand extraordinary evidence right we had to be very sure about the dates from cap Copenhagen that took two more years of hard [Music] work we used a whole set of different methods we looked for organisms in the sediments that we knew lived on Earth for a known period of the past we used the biological clock based on how DNA mutates over time anca's team used three more independent methods to date the sediment from Greenland when their work was done they had made a remarkable Discovery the cape Copenhagen DNA is at least 2 million years old it's important to understand that this is the minimum possible age taking all the lines of the dating evidence as a whole the most likely age of the cup Copenhagen DNA is actually 2.5 million years this puts us into the late P scene which is the period just before we start having glaciations if esa's DNA is that old if it is Pine then that is huge Esa had his hands on DNA from before the last ice age finally we are catching sight of the living world that existed in Greenland before the world grew cold that was the moment that was when we knew we had something to tell the world 16 years after Esa began collecting dirt in Greenland the Breakthrough was published in nature magazine it was covered by over 400 newspapers around the world it even landed on the front page of the New York Times this was one of the biggest science stories of the year until this day the record for the oldest DNA was from a single fossil a mammoth that lived just over a million years ago during the Ice Age using dirt DNA instead of fossils esa's team shattered that record opening a window on an unknown Living World more than twice as old as that Mammoth it feels almost magical to be able to infer such a complete picture of an ancient ecosystem from Tiny frag ments of preserved DNA when I first heard about the results from cop kopenhaven I just said to myself what what we're talking about is pushing the record back to at least 2 million years and I believe much longer than that it was a complete tour to force one of my feelings when I first saw this paper is uh stunned I think we just never really thought it would be possible after years of trying to get DNA from these ancient ecosystems we never thought we'd see such a rich and diverse ecosystem in Greenland we're seeing the very last Arctic forest from a hotter world before the Ice Age and these Force are unique we have nothing like them today I always knew that there was forest in the haak I touched the wood of ancient trees up there but when we looked at the sequences from Greenland there was one that completely shocked me shocked [Music] everyone to hear that there was Mastodon DNA from cap koven Haven this just struck me as whoo how can that be that is so far north relatives of the modern elephant mastadons were Forest creatures that died out at the end of the Ice Age the closest to Cape Copenhagen their remains have been found is almost 3,000 m to the south in North America it comes completely out of the bloom and it was the first time that we found such a large animal in Greenland so after all those years we broke the curse of the Greenland samples I guess you can say it was a breakthrough that immediately became a problem the big question of course is how do such DNA survived beyond the 1 million year old limit that would is the mystery we had to solve it turns out DNA survived such an incredible long time because of minerals in the soil DNA is electrically charged and many mineral particles that you find in the soil is also electrically charged so therefore DNA fragments will basically bind itself around such sediment particles and this will reduce the rate of degradation of these spontaneous reaction that are attacking the DNA and breaking it up so yes it will still be degraded it will still be destroyed but the rate by which this is happening is heavily reduced it turned out that particularly certain minerals of clay and quartz binds the DNA very strongly bound to Clay and quartz DNA is basically Frozen in Time what is super cool about the Greenland breakthrough is the discovery that certain minerals can freeze DNA in time because this means that everything we thought about the limits of DNA preservation are out the window not back to the age of dinosaurs but far beyond the old 1 million year limit so these calls that no one believed in turned out to contain the most amazing treasure it just took us 15 years to find out how to get it out amazing journey right has to be honest I never really lost faith because every limit we have ever set we broke until now what we knew of the Living World before the Ice Age we learned from fossils at the Canadian Museum of Nature Natalia rinsky only has fragments of bone to study but with the spectacular discovery of DNA from Greenland finally a detailed portrait of this lost world is emerging and it's even Stranger Than scientists expected this was a really weird environment you had a forest where half the year it was dark and the other half the year it was Sunshine all day around this means that all the organisms we are uncovering had to survive half the year in darkness [Music] I think the thing that really blew our minds from the ply scene is the camel how could this camel known only by a few fragments of bone survive so far north The Living World revealed by the Greenland DNA gives us some Clues when you think about camels today it's really easy to imagine that they evolv to live in the desert and this is where the finding of the hierarchic camel is so mind-blowing right because it's not in a desert it's living a complete opposite to a desert it's in a forest ever notice how huge a camel's eye is well it turns out they have incredible Vision including night vision that's pretty useful when it's dark 6 months of the year one of the uh most dramatic features of the camel it's the hump it's actually a specialized fat deposit and when you think about the importance of fat energy storage this is something that's also very important for animals that survive through harsh Winters the wide feet of camels you know it's listed as one of the traits that helps them walk over sand also would function well in soft snow we haven't found camel DNA from before the Ice Age not yet but we have now recreated the forest World they were living in and Natalia's F eyes tells us they were there this is a forest that stretched from Greenland to Canada on solid land without [Music] barriers we used to believe that ancient DNA could take you back a few thousand years today we know we can see millions of years back in time back to a hotter time before the Ice Age the pia scene a long lost Epoch that climate scientists believe May hold a lesson for us today the Pia's a big red flashing light right the pene was the last time atmospheric CO2 levels were the same as today you have to go back 3 million years to find a climate equivalent to what we're doing right now that is a CO2 level of about 400 parts per million in the atmosphere the new Pine has begun it's called the anthropos scene we've already altered Earth's climate we're living in a a climate that is about 1° seed warmer globally than it should be the climate of the pene is where we're going it's like our instruction manual for what's coming when the ply scene ended and the Ice Age began that was a big blow but it didn't end life on Earth all life around us has its evolutionary roots in a hotter world including us and that hotter world could hold lessons for our own Survival Greenland proves we can go much deeper in time than what we thought we would we now have the technology to go even further back in time potentially many millions of years we have access to the genetic codes of plants and animals that survived in different climates hotter climates drier climates if we can sequence the genomes of those ancient organisms maybe they can help us and I think we're going to need help the rescue effort has already started scientists in Copenhagen have identified a gene from the Greenland DNA that helped pop trees grow in the extreme light conditions of the high Arctic and they've put that Gene into a modern barley plant one day when our climate is much warmer this barley might Thrive at the top of the world just as those ancient popler trees did this is a food plant engineered for hot future we stealing genetic secrets of the past so we can rescue the future I want to do my part to rescue the [Music] future we are going to sequence thousands millions of ancient genomes from cinnamon samples all all over the world because we are now using robots across the entire pipeline we can do 200 samples a week we are starting an industrial revolution in ancient DNA sequencing Arctic barley could be just the beginning scientists are gearing up to put ancient genes into rice wheat and other Foods to help them thrive in a warming world today we take for granted that all organisms are shedding DNA around in the environment but once this was a new idea it all started with that dog pooping in the rain and that is why we can do this where a little bit of dirt contain contains an entire living world [Music] [Applause] [Music]
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