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tv   David Quammen The Tangled Tree  CSPAN  September 24, 2018 12:59am-2:01am EDT

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reason. prices bring information to consumers. they cannot value it different products in accordance with the measuring stick of money, which as i asked claimed in life after google, money is essentially based in the scarcity of time. time is what remains scarce when everything else becomes the budget. time remains scarce and money conveying the scarcity principle in economics is ultimately based on the scarcity of time. what google does is reached past her wallet in your money in your work and takes your time directly. in an economy without money is
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essentially an economy that is ruled by power and real-time. ..
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>> and tonight's event also
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includes audience q&a and after that time please for the sake of the tv audience raul have a microphone here. and everyone on tv can hear you as well after the talk we
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ask you go that direction when the time comes and have your book signed afterwords now please give a welcome to david. [applause] thank you all for turning out here at powell's and portland are literary hotspots so how many people here in the audience have read the book themselves? >> half a dozen or so. i'm not surprised anybody here ever thought about writing a book? >> [laughter] yes. that doesn't surprise me.
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so i will start by asking you to go along on a thought experiment. if you are pitching it to an editor i want to think about that with me. with a couple of bits of advice. and with this new york editor do not say this will be a 400 page book on molecular science. [laughter] don't even say the lighter side. i promise it is a good way to proceed.
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there are a couple of better ways and one of them look at these two images. that essentially the first evolutionary tree of life of course is an old metaphor to symbolize christ and his blessing but in the middle 19th century to turn into evolutionary metaphor. when charles darwin sketched the little stick figure tree into the transmutation's just
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a couple of years back and was brainstorming his way to theory and evolution. and to become convinced like the trunk on the tree because those that diverged and to diverge further and further with that biological diversity we could see on earth but all of that was represented in this little tree that was the
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first evolutionary hypothesis. this is the tree drawn in 1999 to be ticked away from halifax nova scotia. with brilliant men and women with a history of life on earth is a subtitle to incorporate some of those discoveries made through genome sequence e-letter. with the sequence of units
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with the rna that it is a lot more complicated here on earth and with that darwinian history to be sitting at with lunch at this new york book editor and said want to write a book how this became this. the darwinian tree of life became entangled. that could be a reasonable approach.
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but another thing to say is that i am writing a book about the most important biologists of the 20th century that you have never heard of. and then to ask the editor. and then to say see? >> this man was a microbiologist at the university of illinois and havana in 19 and that with a new form on life that was
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previously suspected in going after questions and from the earliest. three .-point 5 billion. but he picked one particular molecule in all life and that was his rosetta stone molecule the form of rna that exist with all creatures in america and he started to sequence fragments extracted from different forms of life he could grow bacteria in the lab and identify the culture in that extract this molecule to sequence fragments of their
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genomes and then compare the paragraphs of one form of life and how long those lineages had diverge from one another and in the mid- seventies a very primitive form of genome that was toxic chemicals and explosive solvents and high-voltage. and then those grad teams to come up with these paragraphs of dna fragments. looking at the results of one of the strains to realize it
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isn't bacteria at all but this creature it was a single celled creature living in the oxygen-poor environments to produce methane which was thought of as a bacteria was not bacteria at all. he went down the hall and said it isn't even bacteria. not only was it drastically different on the basis of its genome but more similar to animals plants and fungus more similar to us than bacteria but under microscope a look just like a bacterium and this was the third form of life on the front page of the new york times.
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so this living form is a descendent with those primitive forms of life and going back to the beginning it was the archaic and archaeology, old. to publish this scientific article to announce there was a third major form of life. so now the tree of life looked a little bit like this. instead of two major limbs coming out of the trunk like we thought over 150 years, one represents the bacteria, single cell no nucleus or no internal organisms long - - organs everything else is a complex creature instead of those two
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major limbs there was a third one. that was on the front page of the new york times to begin a revolution using molecular evidence. to find out how closely related and how long ago they diverged pico long - . >> a complicated man very private who seized upon the deep questions cobbled
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together those ingenious techniques flouted the scientific decorum to focus obsessively to the exclusion of most other concerns one or two discoveries with the pillars of biological thought. it was an easy funny guy caustic with a love for jazz with that amateur's facility into the grad students and laboratory assistants he was a good boss and an inspirational mentor, sometimes in generous and wise and caring as a teacher in the narrower sense , almost nonexistent as far as undergraduates are concerned. he didn't stand in front of students patiently explaining
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the abcs of bacteria. lecturing is not his strength or interest. even when presenting his work at scientific meetings. he doesn't like meetings. he didn't create a joyous collegial culture posting seminars and christmas parties to be captured of group photos as many senior scientists do. some of those remember good times and laughter just a short walk from the university campus but that select few by charm or luck got through his shallow. and in later years to receive the honors short of the nobel prize also seems to have grown
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bitter as an outsider elected to the national academy of sciences but at age 60 that delay annoyed him. he became distant from his family and the work triggered a drastic revision of the concepts of biology the idea of that tree of life that was the moment of triumph november d 1977 from the new york times. so he is at the center and is the spider in the middle of
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the web. i never heard of carl lewis either. but in the spring of 2013. i happen to read something about horizontal gene transfer. sometimes where they move sideways across the big gaps. from one kind of creature to be completely unrelated my reaction was weight? >> that's not possible but i
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knew enough to think of five reasons why. and that those genomes are wrapped inside the nuclei in one of those functions is that the dna is protected to maintain its integrity. and then to divide to become reproductive cells. with that is one of the cardinal principles the alternate idea with the inheritance and with that
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evolutionary biology proving it is impossible. and jean baptiste with the darwinians looking at that spike over 200 years of the inheritance of the acquired characteristics. so now that discovery of the horizontal gene transfer to the idea that could even be possible and it seems like a version of the inheritance for characteristics. i can talk more about that in
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the question and answer .-period how horizontal gene transfer can happen but we know men and women of the late and early 21st century who did genome sequencing, there has been a discovery this phenomenon is widespread and is rampant among bacteria they do this all the time and that's one of the reasons why antibiotic resistance is such a fast spreading global problem it isn't because they are evolving independently the old-fashioned darwinian way because individual strains have evolved what they are capable to pass that sideways to unrelated forms of bacteria in an instant packages of
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genes move sideways from staphylococcus and e. coli and instantaneously multiple resistance to antibiotics spread around the world so those implications for our own sense of identity. to another boggling fact in the course of the that i talk about at the end of the book with a genome sequencing scientists now tell us that roughly 8 percent of the human genome that has come into a sideways not by direct dissent or vertical dissent but by horizontal transfer that genes
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have come in through viral infections and in particular infection by retrovirus people are familiar with those because of hiv retro backwards it has the rna single-strand virus and it is capable to turn that into dna that is backwards from the usual dna to rna to protein the way it was put into physical structures retrovirus move backwards to infect the cells and then when the cell replicates it replicates the viral dna and then explodes with the viral particles then the person gets aids.
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hiv affects immune cells but as a retro virus egg cells or sperm cells and inserts itself and can be passed down part of the human family lineage. are genome now contains 8 percent dna from that process 100 million years of evolution. one of those stretches of dna is a viral gene studied on the south side of paris. looking at a viral gene
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originally an envelope gene in the retrovirus that it created a membrane it was captured in the human genome, mutated, eve all, survived now with a different kind of membrane that is crucial between the placental and the fetus. so this viral gene now creates a membrane between the placenta and the fetus without which successful human pregnancy is impossible. i think that is bizarre. it does suggest and it was
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explained with these types of genes that because different versions exist in a number of different mammals and it is not found in the premium will lineage it is possible that a viral infection introduced an early form of this gene was a crucial event to allow animals to turn into mammals to keep the offspring internally instead of laying eggs. now there was a membrane. let me tell you what it does. it serves about three purposes
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to transport nutrients from the placenta into the fetus , waste products from the fetus to the placenta so the mother can get rid of them which is crucial for internal pregnancy and also to protect the fetus from the mother's immune system which is crucial because at a genome is only 50 percent similar the other is 50 percent father the mother's immune system would attack it. this protects it against that. if that speculation is correct it could be crucial in the evolution of animals to make it possible that i won't lay eggs on the ground that i have to stand around to protect them i have a fancy new gene
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instead of laying eggs i will be pregnant. this is the sort of thing. these amazing counterintuitive discoveries with extraordinary men and women who were influenced with that methodology of this guy. going back to 1977. maybe i will stop there and see if anybody has questions. >> i heard you this morning
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with some research being done do you know that research is done? >> i was diagnosed with one of the rarest medical conditions they have asked to do genetic testing based on my tissues and they use the term hereditary but they speculate they are not sure how. >> it is unlikely that is related.
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but i don't know those particulars i don't know what miller was referring to. >> carl was here at oregon state. did you know that? >> he was a visiting professor for the summer in the late sixties i believe. my husband is also a scientist and carl was our neighbor and they carpool together to work. [laughter] it was a little disappointing as a wife but the happiest summer of my husband's life. [laughter] it truly was. he had someone to really discuss science and of course these ideas are all before 77 all of these ideas were in his mind it was a wonderful opportunity.
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>> as i travel around i continue to learn things about carl lewis. one of the things that i say another way to talk about this book is he is my citizen kane. this is a crowd that probably knows what i'm talking about this newspaper magnate a difficult mysterious ogre and wonderful man at the beginning of the movie with the word rosebud on his lips that then there is a newsreel journalist who was sent out by his editor to try to collect the story of
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this citizen kane. who was he? >> what was the meaning of his life? >> good or bad and what did he mean by rosebud? >> so the reporter goes around two talks to all these people ex-wives and friends and colleagues in all the different aspects of his character. that is what it felt like for me over the last five years. he is my citizen kane i am the faceless reporter going around to talk to the graduate students and the assistance and the people who drink beer with him but now that the book is published people are coming forward as you have saying did you know this? >> and they keep learning new things. think you thank you.
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>> i have two questions. the first, you say a radical way of life so can you talk about the points of departure from the darwinian theory? >> and how does what you have learned? >> that is question number one. number two, what are some other big questions that interest you in the moment? >>. >> i probably should not give away my next book project. [laughter] at the next question which is very important, where do these ideas differ from conventional darwinian thinking? >> in the 20th century was called the darwinian synthesis which is somewhat different to
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be expanded upon what darwin himself did. the classic view is there are three phases of evolution. first, a variation that arises within populations of integrating creatures there is a difference among the individuals. small differences generally it is thought primarily by incremental mutation, small steps yielding these differences if it is sexually reproducing but the new information and the possibilities come from the incremental mutation the dna
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and copies itself imperfectly over time. because there is always competition there are more individuals than resources with struggles and the survival of the fittest to select from those variants which are the best fitted and adapted to survive. so we agree that is the conventional darwinian view. it is important for me to get across what i describe as the challenges to darwin or what is merely expansion. what is radically new with this understanding is that incremental mutation is by far not the only source of variation within populations
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now we know horizontal gene transfer moves new material with huge genomes of individuals within a population then natural selection happens. so this is in no way intended to challenge the idea of natural selection. it adds to our understanding where the fire - - variations come from in the fact they are not necessarily tiny steps. he could come in a big jump. >> that what drives that organism to transfer in the first place. >> nobody knows the answer to that question. they know that it happens and they study how and why but one of the hypothesis and there is
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several different mechanisms this can occur but one hypothesis is selfish dna. that it happens because it is in the interest to copy themselves abundantly as possible in as many different situations as possible because then they survive. survival of the fittest so if it jumps from one form of bacteria to another or one strain into another, it is increasing the possibility of surviving. then the gene survives over here. that is a reasonable speculation. so what big ideas and evolution are in science? >> i am very interested with the subject as cancer is the evolutionary phenomenon.
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some scientists are working on this it is bizarre and important progressive written one long magazine story on it cancer as the infectious phenomenon it is genuinely contagious tumor in this population of marsupials but it leads from that that involve cancer generally and the implications were accomplished. so i am very enticed by that subject. >> nobody wanted on espn. c-span. excuse me. [laughter]
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are we on espn? >> [laughter] >> so talking about 20 years ago what you talk about makes me think of the ideas about punctuated equilibrium. >> there you go that was 20 years ago. can you speak to that? >>. >> i will a little bit but i won't take it far because he really didn't seem to know about this when he talked about it he meant the fact the record in the snails that he studied and his colleagues and the cocreator of punctuated equilibrium looking at the fossil record not looking at the molecular record trying to explain the fact there are
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things that occur in the fossil record and they argued those leaps do not reflect discontinuity of geological events but they argued it reflected the evolutionary surge when a major change occurred over a short period of time. i got a lot of attention. i never met gould while he was alive but i spent a day talking to his collaborator about this he is wonderful and savvy evolutionary biologist but with all due respect to that idea, doesn't begin to scratch the surface with these men and women are talking about with horizontal gene transfer. >> do you know if there are any significant instances of
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going to other species? >> dna? >>. >> you talk about how it benefits humans. >> know. i do not know not to say it hasn't occurred but to my knowledge, no instance of that has been identified yet. i'm tented to go into a topic of disease about the passage of disease with this emerging virus from nonhuman animals into humans that sometimes you can talk about those viral diseases but that is a different subject in a different book and a different meeting. who else? >>.
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>> you mentioned lamarckian theories and acquired characteristics are passed on and you said it is not accepted but is it accepted that organisms can learn and pass on that learning? >>. >> absolutely. >> so can you explain the mark series? >>. >> i cannot because the one that people know about is the idea of the inherent ability of acquired characteristics. this was before the word gene existed. he wasn't talking about genomes but interpreted now as the suggestion that changes that occur to the body
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morphing of the creature during its lifetime can be passed along to offspring in the genome. that is in the modern sense but learning of course grizzly bears learn and pass to their offspring there is plenty of passing of behavior that is learned. but that is not the genome. but there is a lively discussion about this you have probably heard about epigenetic's. beyond genetics, is a study of phenomenon involving modification of the dna molecule not by changing code but the other biochemical aspects of the molecule that
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affects the way the code is expressed. those triggers and locks and modifications can occur because of things that are done or eaten or experienced during the lifetime of an individual epigenetic modification of the dna and in some cases that seems to be able to be passed on to offspring. that is not part of this book but that is one of the places where lamarckian is him is still discussed in some sense but that didn't involve modification of the actual genetic code. >> how does horizontal gene transfer happen? >> you explained through bacteria but are there other ways?
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>>. >> yes. the fancy term is there are three or four transduction transformation. conjugation and transposing. i can give a quick of each. conjugation discovering in the fifties among bacteria it was suggested bacterial sex to bacterial particles essentially smooch together or a tube that runs from one to another in the genetic material flows down the tube as conjugation it isn't real sex it involves genetic transfer it is not reproduction. transformation was discovered in the 19 twenties in england
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by studying pneumococcus pneumonia and found there were different strains and if he killed a virulent strain of pneumococcus in the same environment and put in the same liquid environment as a harmless strain it could become vera lent. how did that happen? >> it happens by the uptake of the dna from the exploded cells that is transformation uptake of the naked dna from their environment and transformation with floating free genetic information then transduction is a phenomenon performed by viruses they can infect one kind of organism
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and inside those cells talking about a retrovirus can pick up a stretch of that dna and incorporate that into the viral genome that replicates as the descendents go on to affect another type of creature. then they drop the dna that is transduction the general term for a great biologist in the fifties name joshua who studied conjugation calling it bacterial sex but then he started to study other phenomenon calling infective heredity that is a phrase to get an easy handle on the horizontal gene transfer think of effective heredity it is infections that end up transporting dna into the genome of the infected individual.
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>> do your studies specifically on viruses, how much information have you discovered with the aspect of prions? >>. >> with a big scientific subject that fascinates me but not part of this book. [laughter] prions are fascinating but they are not viruses. how many people have heard of prions? >> these were first thought to be slow viruses because they involved the infection process but it takes a long long time for their impact. but now they are known to be
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versions that are inherent proteins are those structures but if a protein there is the right way to fold a map and who hasn't struggled with that? >> if you fold it the wrong way it doesn't fit flat. think of it that way. protein is the map there is a right way to fold it if you fold it wrong but but this miss folding is a contagious
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property passing from one individual molecule to another. slowly over a period of time to have a spongy texture in your brain if you are so unfortunate to have that syndrome. and going as a medical missionary and was a slow virus. and then to discovery it was one of the prions. because of ritual cannibalism
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with the deceased loved ones by eating their brains and that is not a salubrious practice. [laughter] >> and with that crisper technology. and what those implications might be. >> how many people have heard of crisper? >> it is in the news. to be amazingly efficient and precise and reliable and gene
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editing. but it was a big court case on this crisper technology. it with uc berkeley. and i mentioned i have a ten page section because to say please for the love of god. [laughter] crisper in the wild is something that was discovered with a form of self vaccination they engage to protect themselves from viral infection. including one led by a spaniard.
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i was interested in that because that is related with the viruses transferring dna from one to another. but to have more interest in the headlines crisper in the laboratory is a genome modifying technology. that like a lot of people we understand it brings new possibilities to deal with congenital diseases the early fetuses in the fertilized egg that mutations for various congenital diseases ethical
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and societal questions what might be done with crisper to modify or enhance those genomes including the human genome. if people are using this with the assistance like designer babies all children are above average than that raises some serious questions one of those involving the fact if that happens they will not be above average because that leads to all sorts of scenarios. sounding like hg wells.
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is clustered regularly spaced, i cannot do it. [laughter] but it is about palindromes in the dna pico. sentences that read the same front to back and some that cannot be said on c-span but they are in the book. >> one more question. make it a good one. so all of these examples are
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there any that are obvious? >> we know that they can in fact cells so that makes sense. can you give an example? >>. >> yes. we believe all of her heads spending a little bit transposon items within the dna to replicate themselves like a long stretch like 3000 letters of dna. and it might replicate itself to find 17000 copies in those
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3 billion letters of human genomes. barbara mcclintock starting in the fifties with a nobel prize was jumping genes. to jump around first they are on one chromosome then another with this same stretch. but now working with genome sequencing with high-powered computer analysis it has been discovered that these aren't
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just jumping around in the genomes but between the genomes from one creature to another. there is one that is called space invaders and there is evidence to suggest it is transferred from one kind of mammal into another by the parasitic insect known as the kissing bug certain animals including the frog in west africa or the bush baby or a possum in south america also contain multiple context of space invaders and it may have been transferred. so with that light thought now
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we can all go watch c-span. espn. [applause] thank you very much. >> thanks for coming out
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