Latest / El futuro fue ayer con Juan Guillermo Martín / Lo que nos dicen los genes del pasado

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Lo que nos dicen los genes del pasado · El futuro fue ayer con Juan Guillermo Martín

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The future was yesterday? It' s an archaeology podcast where ghosts, conspiracy
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theories and aliens have no place. Ay Soy Jua Guillermo Martín archaeologist and university
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professor and with the hand of different specialists, would be scientifically addressing our fascinating
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past, a past that offers us answers to face in the future. Welcome
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to the podcast The future was yesterday? I' m Juan Guillermo Martín archeol.
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The issue we will address today is complex and has been of great importance
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for a couple of decades in the study of the societies of the past.
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It is the genetics of ancient populations, a fascinating theme that allows us to
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accurately identify the soritas and trajectories of the human groups of the past and the
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present. To talk about it requires an expert. That' s why we
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have a luxury guest. This is Miguel Eduardo Delgado, Miguel welcome. Good
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morning, it' s Guillermo. Thank you very much for the invitation to
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space. For those who do not know him, Miguel Delgado is an anthropologist
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from the Universidad del Cauca and a PhD in Natural Sciences from the Universidad Nacional
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de La Plata in Argentina. He has two decades of professional experience in bioarchaeology
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projects, dental morphology and genetics of ancient populations. He is currently an associate
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researcher at the National Council for Scientific and Technical Research with ISET and head of
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practical work at the Chair of Biological Anthropology at the National University of La Plata.
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It has more than fifty scientific publications. He has been a recipient of
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a dozen research scholarships and is a guest professor at several prestigious universities worldwide.
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To begin with, Miguel would have to talk about the basics to see now
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in the police series and films, that within the search for evidence to solve
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a crime is genetic material, but very few know how these analyses work.
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For this we go to the beginning what DNA is and what it studies genetics.
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Well, Juan Miguel, we could mention great features. DNA is the
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respective acid. Bongocleico is not a molecule that contains genetic information or, in
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other words, the set of physical, biochemical and physiological characteristics that individuals of
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a species basically transmit to their offspring. It is not true, then,
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through offspring, to play an important role in genes, which are the very
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unit of genetic information point as a whole, because they make up what we
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call genome, so then we will take up this concept a little bit.
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Therefore, in genetics he studies the way different types of traits are inherited,
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such as, for example, at the physical level, the core of the
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eyes, different types of disease or even behaviors. It is important to highlight,
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therefore, in this context that they allow to establish relationships between specific gnos
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and morphological traits, but also between individuals and between groups, which is interesting
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and therefore the importance of this type of discipline. Let us say precisely,
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given that genetic relationship between individuals and groups, it is possible to study history
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at both the individual and population levels, basically because in DNA, fortunately,
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different events of the past are recorded. Thus, in anthropological terms, there
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are several types of genetic information that we research, but at least two of
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them have been relevant. One of them is the mitochondrial ene and nuclear DNA,
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which is basically used to reconstruct human history and evolution. You well mentioned
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these two types of DNA, the mitochondrial and the nuclear, in what they
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differ and what kind of information they offer us about a person and about a
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population in general. Perfect, good. Mitochondrial DNA is a particular type of
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DN that is housed in organelles called mitocontras, organized cell tape and basically produced
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energy. An interesting aspect is that this type of DNA is inherited exclusively by
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maternal means, that is, it allows establishing lineages along the maternal line from
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mothers to daughters. It is also inherited from men, but the theme you
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were left in the maternal lines. I mean, a marking is a DNA
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that makes it possible to trace a part of the story. Not then the
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interesting thing is that every human being has many mythocons on average. Let'
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s say, there are some who always have a little less, a little
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more. So, we could say that DNA is more abundant. You may
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have more abundant and relatively easy to investigate in quotation marks. However, the
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amplitude of that DNA is only six five hundred pairs of bases, which are
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more and more and no less than the little steps that one sees in the
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drawings of the elices that join a two- pair base, So that would
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be like the unit of measurement of the amplitude of the genomes And this gene,
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more peacefully, is quite short, let' s say, compared to
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the nuclear DNA, which is found exclusively in the nucleus that encodes, since
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most of the genome. The interesting thing about nuclear power is that it is
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inherited by both parents and although it is much more abundant. For example,
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they are three billion base pairs, unlike the mitochondrial anus. However, the
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cell has only one nucleus, so, relatively, it is a little more
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complex to isolate nuclear DNA for that type of study. However, the nuclear
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area allows for much more implementation of the resolution of the reconstructions of events in
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the past. Here it seems to me that it is interesting to mention that,
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while much was used in mitochondrial and Iran in nuclears is being used in
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the past, variants were also used or still used right of the GM chromosome
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and autosomal type that have also been used in anthropology, much more so because
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chromosomer, for example, would be by maternal way fatherly forgiveness, so it
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would be the counterpart. The nomitocondial allows to investigate the male history and the
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second seriousness of both parents without autosomal markers. And that' s interesting because
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it allows us to work out of bias, for example sex. On migration
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issues, let us think of a married society, which has been collecting for
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an early age, with a well- defined distribution of tasks. Men are
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generally engaged in the exploration house, while women are engaged in other activities.
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And those differential patterns, let' s say, are reflected in DNA,
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because of course there are differences in the way you expect, in the way
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it goes, how you migrate by sex. Then different types of markers allow
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us to infer different types of stories. That is interesting because they allow us
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to understand a little that history always has or some side is not always narrated
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from a specific position, in this case, from the maternal or paternal line,
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or even if we talk about photophomic markers, they usually profit from both
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sides. Miguel Una. Obviously, genetic information and genetic analysis are talking to
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us about the ancestors of a particular individual, but in archaeology, finally,
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we are not going to concentrate. Normally we don' t do it in
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a particular individual, but we obviously seek to understand much broader human groups.
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In that sense, how does what is called population genetics work. Perfect Juan
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Yes, of course, in archaeology we are interested in the group as such
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in the population. A unit of analysis and genetics of populations. It deals
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precisely with the study of the diversity of genetic evolution at both intra and interpopulational
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levels. Yes with an evolutionary context. That is, we try to evaluate
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the forces, which evolutionary forces are involved in the differences and similarities that we
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see between human groups or at the intragroup level. So, from that general
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point of view, we could define that population genetics is that. However,
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since we are talking about archaeology, we must introduce an interesting concept, which
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is genetic art, which is basically the study of TIPS sand to answer questions
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of an archaeological type or related to human evolution. Let' s also say
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it' s used enough today for that. So, however, despite the
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importance of DNA in current studies, when we work on ancient DNA we face
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a wide range of challenges. If among them, for example, once the
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person says he dies, the adem begins to please, depending on the environment,
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it is fragmented, damaged or contaminated and is only preserved. A small
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amount of endogenous DNA does, which roughly goes between point five and five percent.
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Yes, this implies that, in general, the ancient genetic information recovered
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is still scarce and, of course, variable qualities. Let' s not
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say there' s always how there are problems of damage fragmentation. So that
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implies, yes or yes, a loss of information. We could also say
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that good. The history of these analyses, let' s say initially,
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a lot of work was done on the mytocontra sand there, especially in the
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1990s, to understand basically human migrations in the past, yes, through the
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classification of what is called APPLE groups which are basically genetic variants defined by a
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series of mutations. Today, however, thanks to the arrival of more sophisticated
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and high- resolution economic technologies, they have enabled the study of more and
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better high- covered information including complete nuclear genomes and genomes. That is to
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say, we are talking about the complete mitochondial genome and the complete nuclear system,
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which implies a high resolution. Yes, an interesting aspect mentioned that in
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the current technology allows to recover a lot of information and high quality. Of
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course, then this information allows us to make inferences about population processes, even
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investigating only genetic matal of a person, because in each individual events of the
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past were recorded and this resolution is so high that it allows us to infer
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population processes, which is interesting because usually when we work DNA, especially in
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early temporal contexts, we only have one or two individuals or few. Actually,
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then that part is interesting to highlight. And these two groups of some
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have been used in anthropology extensively and especially to reconstruct the expansion of humans from
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Africa to the rest of the Globe, phases of population settlement, population changes
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or replacements, mestizoje with other human populations and even with other founding women and
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mine. So let' s say that, broadly speaking, this information is
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used systematically to investigate a wide range of archaeological questions. At present and on
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these issues, there is one that always continues to awaken controversy, which is,
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finally, the early American settlement. We have had new data for several
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years that show how the presence and age of human presence on the continent has
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been going backwards in time. We don' t go beyond that paradigm.
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Clois, which was over twelve hundred to a series of sites that are beginning
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to offer us a different panorama, especially towards the south of the continent.
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And in that sense, because DNA studies finally begin to gain a very important
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strength in this subject. How these studies are carried out, how long.
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You already said that DNA is finally integrated, how long DNA can last in
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an archaeological context, and how you get those DNA samples from where they come
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out so you can advance these studies. Project Juan Yes, well, the
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history of DNA and especially since construction and archaeology is interesting because let' s
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say, as you well said, let' s say in archaeology it would
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always be paradigms, quite fixed, that are difficult to change from different lines
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of evidence. But antino adine, of course, gives interesting important information.
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Then the picture has gradually changed. Yes let' s say in fact,
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today, for example, very important archaeologists, such as Devitmalts from the United
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States, and it' s that you lose from the Copenhagen geneticists, are
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starting to work together to produce articles that merge the two types of information.
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So that, once the appearance of the ancient adn in the study of this
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type is fruitful to answer these questions on a specific level. At present and
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more than one dk ago we see a kind of boom not of studies of
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palogenomics that try to understand the origin of the first poses American continent, its
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ancestry and genomic diversity, routes of dispersion, time of entry and relationship with
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human groups of other moments of the holocene and the present. Even Yes,
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on a general level, it can be said that these are very complex studies,
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which are expensive, which require a series of technology that include, for
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example, a laboratory suitable exclusively for analysis of old adn. Because there is
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an auto- risk of contamination, high- tech uninformatics is used to manage
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millions of data. Expert staff are required, not only in data analysis,
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which is already enough, but also in how they are recovered and, interestingly,
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how they are interpreted in a geological context. Today we see many geneticists
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who have turned to work on the reconstruction of the human past here in the
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Americas. However, we see that an archaeological background is required is not the
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same as an archaeologist. It is well wondered how the continent has been ploughed,
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for example, your front is evidence and a person who only works the
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genetic part. So it' s basically interesting to mention that. Let'
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s say that today it is necessary, let' s say multicimpre Christmas in
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those projects that require many people working on different yes and great challenges. The
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process of DNA manipulation is radially simple, but not as simple as it seems.
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But good. Initially we choose a bone element which we are going to
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get a small amount of bone dust, about fifty milligrams, as the minimum
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that is being used today and that more or less, because it gives good
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information depending on a number of factors that I will explain already. The DNA
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is extracted, the contamination is assessed, it is repaired because it is always
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one way to identify the ancient sand, for example, it is fragmented.
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Not obviously, with time followed by great damage, then we know we have
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anti- boentogen DNA. When fragmented, it needs to be repaired and then
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amplified through a series of processes and enzymes that are done at the laboratory level.
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A large amount of computer resources are used to read DNA and once it
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is sequenced, we make the relevant comparisons in which we are interested. The
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issue of age is suddenly a rather complex one, because it happens to be
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a question. Depending on the context, then says the adnstopresser depends on different
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factors. The main environment. We know, for example, that in humid
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environments there are higher rates of pollution and fragmentation. It also plays an important
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role in the burial environment, the type of tomb, the type of land
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where it is buried, for example, in acidic lands has very black lands.
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The bones actually degrade very little time, so DNA, not even DNA
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survives. And it is also important to understand that different types of partner elements
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preserve different amounts of androgen DNA. Yes, to date we can say that
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there are studies that have recovered ancient DNA from humans ranging from the three hundred
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years of the present to the fifty zero s in domain in Europe. Or
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modern human is in Europe Pega. For example, there are studies that have
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researched ancient DNA of about twenty- five years a mammoth in Siberia. Obviously,
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the preservation conditions on the ice are quite different. So let' s
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say there is a chance of preservation of high preservation. Depending on the research
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question, we can obtain DNA in the archaeological record of different elements. Yeah,
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the record using the bone would be prefibably if we' re interested in
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humans. Dental calculus is also used. We can also explore lithic tools in
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sediments where individuals are buried, etc. However, there are certain bone elements
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that preserve more or more of the ennentogen, such as petrosus bone. In
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fact, the entire inner ear and teeth are precisely why they are elements that
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are encapsulated in another way, they are protected from a quantity of taphonomic and
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geochemical agents that will directly impact the quality of the DNA we recover. It
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is important to clarify that when we get ancient DNA, the greatest amount of
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DNA we get that environmental line, which includes ADN and other species of animals
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and plants that avoided the same region at the same time or other historical moments.
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So, in that context, we see that, while it is a
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study that is now more standardized, it has its complexities. Of course,
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speaking of that subject, of complexity and conservation. I am struck by this
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project of Liane cyfrianar in the cave of Chiquihuite, where he works with a
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team of German geneticists and when one sees the images, he sees all these
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people dressed in these special white dresses to not pollute anything. But they'
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re apparently looking for DNA in the sediments. How does that work? How
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you separate one, that is, in sediments. I guess there' s
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DNA not just humans, but other living things. How does that work,
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which I find supremely sophisticated. Yeah, well, that' s a pretty
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interesting study and then we can take it back, because it' s one
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of the studies that today, that' s where I think is changing the
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paradigm of the times, especially good. In fact, what is being sought
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is yes, sediments are sought, because interest is not only good. It
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happens that, of course, these early contexts do not have much survival of
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remains, soseos. That' s not true. This is very early that
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we are talking about the last thanks to the maximum. So, of course,
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what you do is you try to do a sediment skining to identify teacher.
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Also the team of vs D also tries or is very interested in the
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reconstruction, for example, of the n of ancient plants to understand a little
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the paleocology of the moments of human occupation. Then, but, however,
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a search is made in the segment separates. Yes, obviously, it is
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identified through algorithms and sequencers. It identifies precisely the different types of DNA,
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different species and depending on the good quality or what is being reconstructed or is
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trying to complete these sequences and are increased by means of informative studies. So,
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in that context, this study, what they did was they looked for
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a series of different types of DNA to understand a little bit the interaction of
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humans and other species, which is also something interesting because clearly it allows you
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to identify, for example, certain plants or animals, there is interaction by
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humans, because it was precisely in archaeological contexts. That work is very,
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very interesting and I think it is one of the works that is beginning to
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change a bit the paradigm of the time of entry into the American population.
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True and speaking about the settlement of America again or taking up the issue genetically,
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where the first American settlers come from. The million- dollar question.
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That question is very interesting. Well, it' s a line of work
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and geneticists. I am of course a specialized non- geneticist artu, but
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I work together with many colleagues and well, some of this one begins to
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understand with the experience of working with them. Today the Asian origin is maintained.
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Yeah, that' s kind of unmovable in the history of humans here
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in America. However, these studies are very much governing the process. So,
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today, we begin to understand that this process was much more complex than
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originally thought. For example, I mix with different Eurasian populations prior to entering
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the Americas. In this final sine. That is interesting because it allows us
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to understand certain evidence that at the time sounded like very unconcordant. For example,
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we' re talking about facial morphology. Yes, they are other different
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traits that are complex because it is also included in the environment, in the
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inheritance, but in another way, they also reflect the population history. So,
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for example, those Eurasian components can perfectly be guilty of finding, for
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example, morphologies as different as Kennetwick in the United States or the Holy Water
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in Brazil, which presents morphologies quite different from what the other Native Americans have
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at the time. Then. On that basis, population models were proposed many
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years ago that included other geographic sources of origin for American climates, including South
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- East Asia or Europe. Yes, Another interesting thing is that it was
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established in a very concrete way that prior to entering America, there was an
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important genetic isolation in Beriencia that roughly ranged between two thousand and seven thousand years.
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Another very interesting thing that is going to count on the work of the
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people that you just mentioned the piersde team is that the time of population now
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is getting deeper and deeper. We don' t see that, let'
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s say there' s more and more. We are getting more and more
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to the last, the maximum and this more agreed. What we talked about
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with CristóbalÑeco many years ago about the way scientific revolutions are or in the
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book of Thomas Coom No. So it happens that this kind of empirical harmonies,
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especially this kind of evidence, which are showing us, for example,
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that humans arrived in America long before what was thought and what was believed under
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the previous paradigm, we began to see this normality. Sites with evidence are
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beginning to appear much more temprant than was thought, and those evidences are becoming
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the common one at some point, and that is what allows the paradigm to
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change. So, today, we are no longer talking about moments of entry
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into America, for example, sixteen thousand years of fifteen zero already we are
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reaching even evidence of twenty zero even twenty zero years. Last year a very
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interesting work was published by some Brazilians where they found tools made of mega fauna
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bone. Yeah, and they date it back to twenty- six zero calibrated
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years. For example, yes. Here I allow myself to introduce a work
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that we are recently about to publish, where in Argentina, in the pampa,
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we are finding evidence of mega fauna with cut marks of anthropic origin that
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are twenty- one thousand years old. Yeah. So, in that context
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we are seeing that more and more dates are going a little bit backwards and
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we always start to see other works, for example, published in istan as
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important as Science in North America, found Wrage. This is already very detailed
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analysis and the prints also point to being the last, the maximum as the
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moment of entry. If something that has already been proposed since the 1970s with
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Rup Grun and Alan Brian, for example, then all these models are changing
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over time and right now we are in those moments where we are beginning to
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see a temporary deepening in the entry of humans. There are also routes.
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The expansion routes are being better defined by both the Pacific and Atlantic coasts,
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and there will be complex relations between the first settlers and the later settlers.
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For example, they can happen to recover adn from Ancy in the United States
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and it happens that ansi has much greater relationship with all South Americans and not
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with Americans. This team is beginning to visualize precisely linked to the fact that
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certain population events, such as expansions, contacts with other groups or even given,
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leave a record in DNA. It is possible to reconstruct events from the
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past. These events are recorded basically and in the form of cantes in DNA.
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Or mutations that are the approgroups yes both the ennemitochondial and the chromosome,
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there that allow to trace the ancestry of the human populations to their origin,
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Africa, if you mean, let' s say that human expansion after the
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sixty zero years. For everything, the globe involved every time it reaches a
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region, it implies changes, of course, of certain adaptations. These adaptations
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are being fixed on DNA and that allows us, in one other way,
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to reconstruct human history. Of course, we know they share an origin with
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Asians. Then there are the same ap progroups, but even in some more
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due to processes like mixing with other populations, as I mentioned or the intrapopulational
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evolution that occurred here in America directly. There is a topic that is also
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key and that generates genetic studies of populations and has to do with chronology,
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with antiquity that is. We obviously have radiometric methods that allow us to establish
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those numerical chronologies. But in the case of genetics, how it works,
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how it is possible from a genetic study, to establish or define an antiquity
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yes. But at present there is an impressive development of statistical, sophistical and
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complex methods to establish relative chronology. It is important to assault the relative of
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certain events. These methods allow to estimate the divergence or amount of time that
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has elapsed since the occurrence of a mutation yes or, for example, a
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pro- group that appears pru dot. We can understand the time that has
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passed, we can more or less yes, more or less understand a little
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how much time has passed. Or we can also build on the number,
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number and quantity of differences between DNA sequences. We can also establish a little
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chronology but for this case we assume a relatively constant cant index that we see
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that in models those are not always so. For example, I give a
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very interesting example. In the two thousand sixteen appears one of the most complete
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and best works done to the date of mitochondrial that we have not seen tell
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them to understand for the early of America. Yes, and at that time
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it is given through phylogenetic analysis of coalescence, which are basically these methods that
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allow to measure the amount of differences between sequences. The attempt was made to
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establish the chronological age of the four pro- group yes, that of four
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pro- Tahnochondrial, which will be the fairy, that of two, the
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one and that of four, and those methods cast an age for the ancestor
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as more recent than nineteen zero among nineteen, thousand, seventeen, thousand,
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two hundred and ninety- five years before the present. If we look at
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the theological record today a little bit, we are more in agreement with these
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dates of that work, which is already a little old, which is almost
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ten years old. However, my opinion is that, if these methods and
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models are very useful and sophisticated, they should also be viewed with caution,
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not precisely because they should be calibrated with other types of evidence from the archaeological
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record, as with materials that are reliably dated. So, because they do
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not exist in America in human remains from the first moments of occupation or even
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exploration, molecular clocks must be seen as a line of complementary evidence that can
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also be combined with other logical records. But I insist that these methods have
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their value. Of course, they are interesting and, in fact, the
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predictions they make are usually very accurate, but yes or yes they require a
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calibration with the scological record as such. So that allows us to understand a
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little better that there are many lines of evidence and this alone does not have
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as a contribution beyond the sophisticated that is required yes or yes of the archaeological
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record, that is, a contrast, obviously, with the rest of the
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archaeological context. But, because it shows us that it has its level of
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precision quite high there is another. It is clear that, as these genetic
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studies have revolutionized research on the past of the American continent. We have begun
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to see through these studies, many of them in which you are directly involved,
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in which are identified relationships of the pitches with land, even one that
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is showing us a relationship of North South America, particularly of the current Colombian
31:23
territory, with Polynesia. What are the recent developments in this area? Yes,
31:33
Juan Guillermo, Actually, at present, as I mentioned well, bonus
31:37
of these studies and there are more and more continental studies, that is,
31:41
for example, there are many bonds of local studies. Yes, and now
31:44
there are reviews already at the continental level. These studies are quite interesting because
31:48
they allow undiscovered and there are new interesting findings. For example, the most
31:57
interesting thing that lends me is that it is complementing itself. If you used
32:00
to talk almost always about good, if the first Americans arrived and almost in
32:06
a marathon race they reached South South America land of fire. But today we
32:10
understand that process with reality much more complex than was believed. And that'
32:14
s where it seems to me that part of the importance of these studies lies,
32:19
and the current thing, for example, is that something very interesting is
32:24
that, for example, or is spoken from the studies of lithic technology,
32:30
a possible relationship between the first Americans or even pros of Bering and the pre
32:35
- zenic inhabitants of Japan. It was always proposed, above all on the
32:37
basis of the relationship of lytic technology. However, the andalus of palo genomes
32:39
and other evidence pines, such as the ogintal morphol, show us that there
32:45
is definitely no close relationship at biological level between the Pristocene inhabitants of Japan,
32:52
the islands of Japan and the first Americans. However, it takes up an
32:58
interesting problem that is basically good how the process went. They migrated ideas,
33:05
migrated, technologies are grogent. Not then. In that sense, this allows
33:08
a little bit more complexity to the picture. At the same time, recent
33:15
studies have found that there is some trace of relationship with East Asia, which
33:21
we know is East Asia, but more than the entire Northeast. But in
33:22
this case we are talking about relations with groups in central China. Yes,
33:27
today, we now know that some of the tenuous Americans have some relationship with
33:30
people who lived in central China during the final sine position. The mestizoge has
33:36
also been recently found, I think, the entry into America that suggests genetic
33:40
and Eurasian management components. And that, as I mentioned, is interesting because
33:45
it allows us to understand other problems, such as, for example, what
33:49
I mentioned to you, this possible relationship between these Eurasian genomic components and facial
33:59
morphology of people in the American rivers at the theological level, which seemed to
34:06
suggest that they were so different from Native Americans than probably from other population sources.
34:09
And one thing that we do draw attention to and I myself have been
34:13
participating in these works is the relationship or miscegenation detection of the ances of the
34:20
first Americans with omninos in Asia. And these are the Denisons, who are
34:25
some who lived in eastern Asia between four hundred thousand and fifty thousand years.
34:30
So many present, more or less and have been found, for example,
34:35
in DNA, in pre- Hispanic populations, especially early smos and ready at
34:40
the end, a trace of DNA is useless and also in populations today.
34:45
Yeah, so it' s interesting to know how this kind of study allows
34:50
us to get so far back in time. We are even talking about such
34:52
interesting events as mixing between modern or anatomically modern humans and other Dominican species,
35:00
such as denisobans. Yeah, about the Polynesian and American relationship, well,
35:07
that' s an idea that' s always been maintained over time, for
35:13
a long time. If now the relationship between Native Americans and populations of Southeast
35:15
Asia, Austalia, Melanesia, even from Paul Rivet, this is being mentioned.
35:22
This is not something so new that these models are being proposed and have
35:25
been poised over time on different lines of evidence that have supported or not supported
35:30
this model. Yes, recently, in fact, as you well mention Juan,
35:36
two different research teams investigated a more complete genoese and, independently, found
35:42
a component of his asiato that in the current, historical and pre- Hispanic
35:47
nameric groups. However, this is a very complex issue, because, well,
35:54
you know that they have also been political in scientific research. So,
36:00
for example, there are rival groups that tend to criticize each other' s
36:04
outcome. So also these polognamic studies are not exempt from these kinds of polemics.
36:12
Then those same researchers took out other papers saying that it wasn' t
36:16
really like that and that that relationship with southwest ace was basically a false positive
36:22
of misdeeds. Or even if he spoke, for example, that some component
36:29
of that could come in the slave trade across the Atlantic, because many of
36:36
the people involved in this type of activity came from Southeast Asia. However,
36:44
the truth is that in a very recent article, because you had a colleague
36:47
in Brazil at an important root, it detects that there are ancestry of Melanesia,
36:57
Polynesia and the entire region of Southeast Asia in today' s indigenous populations
37:00
of the Amazon region of Brazil. Yes, and they' re not very
37:04
Indian, they' re groups, they' re current populations. The truth
37:07
is that we still don' t know what the origin is and how it
37:12
got to America. Even studies of palogenomas are saying that this early sign of
37:16
possible relationship with Polynesia is given long before the entry of American villages. Yeah.
37:25
However, the survival of current populations with that type of DNA marks a
37:31
giant question that needs to be resolved in the coming years. Yes, and
37:36
for the sake of saying something quite recent and interesting about what is being done,
37:42
it is for our region, for example, that it is the human
37:45
expansion that took place in the Middle Holocene from Central America to the north of
37:51
South America, which is beginning to be understood, that introduced maize agriculture,
37:54
for example, to the north of South America, introducing pottery, probably the
38:00
chicha language in a certain region, is like, for example, the savannah
38:02
of Bogotá. So, those studies are bringing about that those population expansions and
38:10
those, for example, changes that I myself, in my studies of morphology
38:15
isotopes, see changes at the population level in the Bogotá savannah that were difficult
38:22
to explain without DNA. Let' s say that DNA has a high value
38:28
as a line of evidence, of course, and it' s beginning to
38:30
confirm that, in fact, those dietary changes so abrupt that you saw,
38:35
and those changes are burial patterns, even in lytic technology or in other lines
38:40
of evidence, have certain senses and we evaluate them as the arrival of new
38:46
people from Central Central America. And in a study that I was about four
38:50
years old, but I think it' s interesting to mention it, in
38:53
which I collaborated we addressed the palagenomics of the species cavia. From archaeological and
39:00
very interesting contexts. We were able to establish, for example, two different
39:05
domestication centers, yes in South America, one in Peru, another in Colombia.
39:07
The one in Colombia is very interesting because apparently it is a species with
39:14
a species different from the one that was being consumed in Peru for the same
39:17
moments, more or less. So, this line of palogenomic evidence is starting
39:22
to help you understand things like, for example, domestication. Yeah. Also
39:25
in that work we were able to establish the steps of expansion of North South
39:31
America towards the Caribbean, for example, yes and other regions of the world,
39:36
already after saying in more modern times, that would be like a very
39:39
small panorama, very short of the current in the advances in palognomics here in
39:45
America. Of course, that is another subject that we will probably have to
39:50
discuss later and that is related to the genetics of other species, not of
39:53
human beings, but of animals that we interact with directly, as you mentioned
39:59
the one that was there, which is the and famous one that is still
40:07
eaten in the Colombian suroccident and, well, in the whole Andean region.
40:08
And that' s another line of work you' re working on here.
40:21
There is another issue that is fascinating, Miguel, and it has to do
40:25
with the fact that it is now also possible to recover genomes of ancient diseases.
40:30
That' s how it works. That' s already this high-
40:37
tech science of the 27th century. Yeah, yeah, yeah, well,
40:40
these studies have a major breakthrough. Not me, actually, this is moving
40:45
so fast. Let us say today, for example, we do not know
40:50
full genome studies of thousands of people across Europe and America. I mean,
40:55
let' s say today there' s a lot of progress. No.
40:59
So, in that context of progress has become, a standardized practice has been
41:04
shared, as in the search for ancient pathogens in all of these is,
41:09
progenomic. So you' re investigating a sample, and the first thing I
41:14
do, apart from recovering DNA, is to make a skin of possible pathogens
41:19
and, obviously, of course, the diseases that were present in the past.
41:22
Also and fortunately, it has been possible to recover DNA from certain pathogens
41:30
Yes, because, besides, like our old- fashioned you, you are
41:32
increasingly beginning to understand how certain pathogens affected the populations of the past. So
41:39
what is done is to identify the pathogen, build the DNA and make comparisons
41:44
to understand, therefore, the interaction between human beings and that pathogen, the
41:47
disease it produced and the relationships with other species. Generally, what we are
41:53
talking about is just thought, especially trying to understand how it happened, for
41:59
example, the contagion of certain diseases that usually have to do with vectors,
42:02
that is, with animals that infect humans and produce a series of mutations,
42:07
which, for example, causes very complex diseases to occur. So that'
42:13
s starting to be understood now. Yes, and this seems interesting to me
42:20
to mention two cases. Yes, it is the case of turculosis in Peru,
42:23
where several years ago but it is a rock that seems very interesting to
42:25
me. Turculosis was identified. Tuberculosis genomes were recovered from individuals who lived about
42:34
1, 500 years before the present in Peru. However, this study is
42:37
interesting because it allowed, for example, to identify that the probable contagion editor
42:43
was seals. Yes, then it is beginning to be understood that this human
42:50
interaction other species affects human history in a complex way, not only in the
42:55
context of economic exploitation or as ornamental or of differentíndo and the species,
43:04
in this case, animals, but it also has direct relation to some types
43:07
of diseases and in another case that good that out there you already know more
43:13
where we have been presenting what we identified in the savannah of Indian dumped the
43:19
medium ceno we find an individual contraparometosis. Yes that group of diseases, like
43:23
VG, cyfris, paints it, is not true and it is interesting because,
43:28
at least that study is helping us to a lot of things, among
43:32
them that the origin of these diseases and the global discretion that occurred in the
43:37
sixteenth century, say, America. In America there was already that disease.
43:45
Obviously, we probably knew it wasn' t the same CEPA, but it
43:49
mutated over time, with even different species of pomamas. However, we are
43:53
beginning to understand that certain hypotheses and models about this type of contagion are not
44:00
as much as we thought. So because the line of stalogenomics is recently revealing
44:06
this kind of complexities so classy traits. Today, it is possible and it
44:14
is becoming more common that the work of palogynomics also focus a part on pathogens,
44:17
which allows us to understand not only the answer forgiveness only the disease.
44:22
It' s a human response, the social response, for example. An
44:25
interesting aspect that we saw here in the Bogotá Shroud is that well, that
44:30
person who suffered that type of illness survived in time if an average adult personality,
44:37
and this person why he surely survived by a social context, that is,
44:40
how that disease also is unknown in social dynamics, in social imagination,
44:45
and how there was a series of care and how a whole accompanying response to
44:50
this person. So all that kind of questions, which are so complex to
44:53
understand, because we talk about behavior and past behavior is quite complex to understand.
45:00
From the fragmented to the record. Precisely this line of view is offering
45:04
us a new window that probably in the future informs us of even more interesting
45:09
events. Yes, and now there is, in addition to these advances in
45:17
genetic studies, the possibility of predicting the morphology of people of the past,
45:24
and this is something you work on directly. How this works, What are
45:29
the scopes that offers us additional to the study of the past this type of
45:35
approach. Well, yeah, well, these studies are based on availability or
45:40
the amount of work that was done decades ago. Say, there is an
45:47
impressive amount of older sign already available for use and comparison, but there are
45:52
also a number of current population data. Yeah. So these studies are basically
46:00
those databases of the current populations to identify genetic variations, for example, which
46:05
encode for the skin cord, for example, eye pain. Yes, and
46:08
then that bal is searched for in the oldest gero databases, yes, you
46:14
can say it in some way and with great features. Then, after identification,
46:19
predictions are already being made. This has to do with, for example,
46:29
the prediction of different genotypes such as the cor of the skin, the
46:31
tall eyes among others. Yes, and training model is created on a statistical
46:37
level and we basically use many new methodologies, such as artificial intelligence. Yes,
46:44
then, in those genetic variants related to the morphology of interest, that
46:51
allows us to identify, identify those same variants in which no older and what
46:55
allows us to infer in some other way, predict, according to the characteristics
46:59
of the most current genes, the possible cor of skin of people. Yes,
47:04
this has to do, for example, with the idea of beginning to
47:07
understand diversity a little better. In the past. For example, there is
47:15
a very interesting study, published about two years ago, where they identify that
47:19
one of the first modern humans to arrive in Europe, especially in the part
47:29
of England, that whole part of Britain is about twenty thousand fifteen zero years
47:34
this person and it happens that that person was predicted a number of genotypes,
47:43
cover of movies, of eyes, especially and in an interesting way, for
47:46
example, that he was a person who had dark skin, but had clear
47:49
ogies. Twenty thousand fifteen zero years ago. So it is interesting to understand
47:54
that, in that context of global expansion, humans suffer a series of adaptations
48:00
and changes. Of course, Africans or Africans are adapted to a specific environment
48:06
and environment with a solar radiation, to specify that that' s why the
48:08
tone of the clear skin We don' t all realize that by migrating to
48:15
regions much more latitudes, that part began to change and we found people who
48:23
were already adapting twenty thousand years ago. And this to say also to build
48:27
a little bit on the issue of the inoperability and effectiveness of racist discourses from
48:30
science. This also helps, promotes understanding a little better than that amount of
48:37
differences that we humans have today are different in another way, very subtle.
48:42
Not the genome is the same, and that helps us to rule out differences
48:47
that have been based on many discourses, especially on the social side, to
48:52
promote differences between populations in one way or another. And this seems quite relevant
48:55
to me because it has a direct impact on the social and political issues of
49:00
today' s societies. Yeah, I' m just working on a few
49:06
prondos with the researchers We' re predicting the skin cor using genomes from the
49:14
databases And we' ve found that roughly the two zero persons who lived between
49:20
ten zero two minutes of the present. If ten thousand and two thousand years,
49:22
more or less, those people had a higher diversity of the skin cord
49:28
than the current populations. Of course, then that allows, in one other
49:30
way, to understand also the joint evolution of different traits, not only DNA,
49:37
but different genotypic markers, which is interesting because it also allows to tell
49:44
a story as a whole. They are no longer isolated pieces, but we
49:46
already began to unite them to understand that human history a little better. Of
49:52
course Miguel Ya. Finally, to conclude, what we need to study and
50:00
know from a genetic perspective of the populations of the past to the present to
50:06
where it allows us to reach the available technology and what are the great questions
50:13
that you, from this area of knowledge, are asked and intend to solve
50:19
in the coming years. Well, a complex question. That depends on a
50:22
number of factors and, above all, the researchers' interest. One thing
50:28
that I find interesting is that these studios usually leave more questions than answers.
50:31
Then I force you to keep looking, to be inquiring and to continue designing
50:35
research proposals to answer them. The use of current technology and DNA and ancient
50:42
sand makes it possible to increase considerably the resolution in the reconstruction of different processes
50:49
and events of the past then, for example, it seems to me particularly
50:54
worthwhile to start researching regions yes they are very biological and cultural, but unfortunately
51:00
they have not been investigated. And for example, Colombia. Yes, in
51:07
Colombia it is one of the most interesting countries because it has high biological cultural
51:14
diversity, but it also has a strategic position to investigate the initial population of
51:17
South America. And already in pretense that just now, with the project that
51:21
we are working on, in which you are a part, of course,
51:25
we are beginning to fill this gap of information and that seems valuable to me,
51:30
because it is a region that is very important at the level, for
51:36
example, what we were already talking about the probable expansions of Central America to
51:43
the north of South America, that they carried the corn agriculture or carried the
51:46
chicha language well. So, then this is allowing us to better understand those
51:52
origins of that series of populations that, of course, was the relevant one,
51:57
because from there down the whole subcon started to be put So it seems
52:00
to me that one of the questions, or one of the interesting approaches would
52:05
be to address this series of regions of South America or even from other parts
52:10
where we know they were relevant to history. Yes, but beyond human expansions,
52:14
it is interesting to address the processes of domestication, precisely of different animal
52:21
species, to better understand that relationship and interaction between humans and other species.
52:27
Then it seems to me very interesting to start studying research processes, because it
52:34
happens here. Obviously, in America we had in different regions, different species
52:37
of which we sufficed, of course, and were domesticated. So it'
52:43
s very interesting to understand how that process was carried out at what point we
52:49
mostly ask one of the fundamental questions in the moments of initiation and domestication and
52:54
the line of palognomic violence allows us to rebuild that. Yes, it seems
53:00
to me that that is a relevant question, because it has a diversity after
53:05
college, of environmental and site environments. So, one of the big questions
53:09
is to understand human interaction a little better other species in terms of adno study
53:15
and from an interesting theological, it also seems to me that it is also
53:20
much worth beginning to evaluate those relationships of kinship between populations buried in the same
53:24
place. Yes, the study of the preservation of the lineage over time,
53:30
the change of the patterns of postmarital residence, for example, and this relates
53:36
more to one more Escuera of the social order. The group of the past
53:39
one tends to visualize, for example, well if we compare groups from the
53:44
north, Central America and South America, more or less, we understand a
53:47
little what the form of expansion in the continent would be like. But also
53:51
these studies allow us to formulate a series of questions of origin more at the
53:58
behavioral level. That' s very valuable. Because this line allows us to
54:05
answer, obviously partially, but much more precisely than other lines of evidence these
54:08
kinds of questions. Not then is the potential of the ancient herring to answer
54:15
those questions, for it is impressive. I mean, archaeology has a tool
54:21
or a pretty strong line of evidence for further investigation. It also seems very
54:25
important to me, for example, in the local academic context of Colombia and
54:30
other Latin American countries, because there is a great need for academic and quality
54:36
training of postgraduate students in this subject. It seems to me that it would
54:40
be very interesting that we directly here in Latin America, have the possibility of
54:45
doing this type of study having laboratories having trained personnel to carry it out,
54:52
because this obviously requires a lot of resources, but it also requires staff,
54:59
as people interested in the subject that want to work it. So it seems
55:01
to me that for development to be lines of evidence is key. That doesn
55:07
' t seem relevant to me, too, to understand the implications of these.
55:16
That has to do basically with the bioethics protocols that accompany this type of
55:22
studies, especially because there is one thing with a guillermo that is very interesting,
55:25
important and it is about the relationship that is woven between the populations of
55:30
the past and the current populations. And that is not a minor thing,
55:35
because in reality people do care about this and it also becomes a topic of
55:40
discussion about identity and, therefore, it is a political discourse. So,
55:45
for example, there are populations that are very interested in knowing how to relate
55:50
is such with other populations. Yes, in the past and on that basis,
55:52
well, I don' t know say, very controversial discourses or discussions
55:58
have been generated, for example, in the United States, in other regions,
56:01
and that seems to me to be important to take into account also to
56:07
mention, for example, that these researches must incorporate community participation, this academic
56:14
one, they must do with public disclosure and they must promote a bilaterality and
56:20
horizontality of knowledge. That is to say, it is not simply in what
56:22
was done before me, as an archaeologist I go and take it and do
56:28
the analyses, but rather understand a little better that impact dynamics in the Community,
56:32
because the Community is more static. The past is not static in that
56:37
sense and let' s say we can dynamize it, incorporate people more,
56:45
especially from the extra academic branch. Let' s say people who care about
56:49
this kind of thing. It seems to me to be a very valuable thing
56:53
that should begin to be done, that not all the research teams working in
56:57
this line of evidence do and that, of course, we would be talking
57:02
basically about a form of human colonization. Today I take out the teacher and
57:06
the public and I put you in as author, but it seems to me
57:08
very interesting the theme of working this whole series of protocols and of convening a
57:15
lot of local institutions and local communities. So, well that weird thing could
57:19
be juan my perspective on the issues that could be addressed in the immediate future
57:24
with this line of evidence so interesting work on what' s definitely in this
57:30
line. Evidently understand, of course, that we currently have a genetic relationship,
57:39
one way or another with those populations that you and your team are advancing.
57:47
And in that sense, it is not just a matter of genetic study
57:50
of an ancient population. No, that ancient population has a direct relationship with
57:54
us and in that sense, because it is important that this knowledge reaches the
58:00
general public. So Miguel, nothing, thank you very much for your time
58:05
or for your generosity. It has been a privilege to talk to you,
58:09
as you are a leading specialist in this subject, so it remains to say
58:16
that we will continue to produce scientific content in this podcast. Your future was
58:20
yesterday. Thank you very much.