 Hello and welcome to Newsclick. Today we have with us Professor Satyajit Rath and we are going to discuss one person who has recently left us, Richard Leventine at age of 92 who has had a very, very distinguished career in population genetics and a whole bunch of other things he has done, particularly also relating science to ideology with social action and of course, what is the kind of society we want, including the kind of science we want. Satyajit Leventine has been a towering figure in his field. Can you tell us what are the key scientific discoveries that he made here and along with his colleagues did, which is the reason why he is recognized as one of the founders of the discipline. So Richard Leventine was a remarkably interesting figure in biological scholarship and in order to appreciate what he was, both as a scientist, as a biologist and as a public intellectual in the progressive category, there is one peculiar characteristic of Leontines that we should all keep in mind. He worked in interface domains. He thought between classical fields. So Leventine worked in genetics and in evolutionary biology. So let me therefore start there. Can you tell us what the two disciplines are because for a lot of people they are both biologists. So Leventine's great contribution was when we think about evolution, we think about Darwin, we think about species, we think about animals, birds, plants in real life and how they compete, collaborate, cooperate with each other and how new species are formed and so on and so forth. This is all macro-scale. But the reality is that when these characteristics are inherited and inheritance is an absolutely key feature of Darwinian evolutionary ideas, the inheritance is at the molecular level. The inheritance is at the level of the DNA that every generation inherits from its predecessors. The characteristics, the traits as biologists like Leontine call them, the traits are determined by genes. The connection between a trait and a gene is not straightforward because genes are at the chemical level. Traits are at the observational level. Does a giraffe have a long neck? That's a trait. What are the genes that lead to a giraffe having a long neck is at the molecular level. This is a difference in levels of organization and one of the questions that Leventine asked was significant in two different ways. One was that he was bringing the methods of molecular chemical analysis to questions of evolutionary biology. So the molecular scale organization question was being asked in the context of the macro-scale of organization and this is one of the things I'm talking about when I say he worked between domains. So this is an example of how he worked between scales of organization. In fact, I would argue Leontine was amongst the very first, if not the first, to do this. But not only did he do this, he did it in a remarkably insightful way that gave us an extraordinary insight into evolution. And let me explain that. We tend to think that a given species all has the same traits, the same characteristics, the same behavior. All animals have the same behavior of a given species, for example. We also say that from species, from pre-existing species, new species emerge. If that happens, then the pre-existing species must have some variation from which slowly, by selection, new species should emerge. There has to be variation within the species. There must be variation within the species. How much variation is there within the species? And how much variation can exist in a sort of equilibrium where the species is not changing, apparently. And yet there is a great deal of variation. This you will appreciate is a fundamental question in how evolution works. And Leontine in the 60s and 70s did the early pioneering experiments using what he used to say his lab excelled in, which is the simple method of gel electrophoresis, which is a really chemical method, to begin to ask how much is the genetic diversity within a species at a number of positions in the genome, at a number of different places, at a number of gene locations. And he showed us the extraordinary fact that any species apparently at equilibrium has an enormous amount of diversity, genetic diversity in it. And this finding is fundamental to the extraordinary respect in which Richard Leontine is held by biologists who have all sorts of reservations about his work, about his politics, about his public intellectual perspectives in they are all unified in this point of respect for Richard Leontine. And it is this point of respect that leads us to Leontine's connections as a public intellectual to his social perspectives and to his politics. When you say that he actually brought these two different parts of the puzzle together, there is also a third element of the method he used, which is of course, biostatistics. He was one of the earliest to use extensive biostatistical formulations to look at this. And of course, the major, shall we say, political implication of what he did was when he applied it to the human species itself and showed that race is actually a wrong way to look at variation within the species. It contributes a very small element of the differences we have. Most of the differences are within the races and in fact, even in a smaller subsection. So let me, let me press you a little on that. What you're saying is absolutely true, but that's not all of it. So he's finding that there is enormous genetic diversity in a given space had two implications. One, as you point out, that so-called races had such massive genetic diversity that the differences between race and the differences between races contributed very, very small fractions of the genetic diversity of the species. And therefore, Luantin was fond of saying, race is a biologically meaningless concept. And that is not true, for instance, in different kind of species in the animal kingdom, where there can be significant differences between groups. In this case, race does not really cover that. And that, of course, is politically significant. For some time, it was argued that he worked at the level of proteins, but later on geneticists have shown, I think Burjani showed that it is also true. The same diversity that he established using the techniques that he did was also possible to show using genetic diversity methods. So that was one part. And this brings us directly to the question of also the other part which is really much more focused on evolution. He with Stephen J. Gould, who's of course known much more because of his popular writings, also had a major paper on looking at evolution and what they call the Panglossian paradigm. Can you tell us what that really implies? So that was the other contribution that I was implying. Think about it this way. When you say, when we say as Luantin did initially, as you say, at the protein level and then subsequently, he as well as other people at the actual gene level, that there is enormous diversity at the genetic level within a species, he pointed out that what that meant was that every variation was not immediately getting selected for or against in evolution. This notion that evolution was a cutthroat competition was not jiving with this extraordinary diversity at equilibrium. What he was then pointing out was that the diversity meant that any variation at a particular gene could exist with a different background context in this individual and a whole different background context for other genes in a different individual. And therefore, the possibilities for how individual outcomes would vary in their traits, in their characteristics were extraordinarily diverse. And he pointed out therefore that simple arguments about evolutionary directionalities that here is a trait, it emerges, it competes and you get a new trait fixed and then you get new species fixed where unlikely to be correct. The so-called neutral variation is a major component of evolutionary directionality. And it's in that sense that he and Steve Gould made the argument that in fact, what sometimes happens is that as a certain trajectory of selection happens on that trajectory, incidental things also get dragged along. They don't necessarily have selective value during that particular episode of selection. But because they have co-emerged as associated the emergence, they therefore enable future evolutionary directions in a completely different context to become possible. And this is what Gould and Luantin called the idea of the spandrel. So the idea in a sense that Luantin and Gould came up with was that if you have an external ear emerge as a trait, the shape of the external ear means that some parts of it, which are not necessary for the original function of the external ear, which is to serve as a directional device, but some parts of it can sometimes be useful in the future for completely other purposes, such as, for example, growing fur and therefore being able to do temperature control. That's not a great example, but it is certainly the kind of possibility that Gould and Luantin had in mind. Architecturally, the word spandrel comes from architecture, where if you have support systems, the triangles in the angles, the supports in the angles of doorways and arches, for example, could then begin to serve as places where you can put light fixtures as places where you can put sculpture. So all sorts of unforeseen future users of an earlier structural associated change shaped future directions of evolution in complexly interesting ways. And this was very much Gould and Luantin discovery, but in Gould and Luantin formulation, but in more general ways, what Luantin was always pointing out was that this meant that evolution was far more contingent and topical, incidental than a simple, oh, competition, fitness, survival kind of formulation of the original Darwinian notions. Number one, number two, that just as individual organisms were reshaped by their genetics, in turn, their behavior altered the environment in two different ways. One, they were each other's environment. Remember that our ecosystems are actually species coexisting with each other and having effects on each other. So we are each other's environment. Number one, and number two, we change even the nonbiotic, the nonliving environment. We dig, we build, we divert water, we use water, we breathe, and we change the environment. So he kept pointing out that this was not a simple matter of genes and environment, that this was an extraordinarily complex give and take between the genetic inheritance of the individual and the environment, which consisted of the genetic inheritance of other individuals, as well as the effects of species on the environment. And this was why, this was his second reason, if you like, for being very decidedly against genetic determinism. You know, this of course brings Leventine's other work, which is how he saw himself in society, how he saw himself as politically as an activist. He also took up, of course, the race issue, which is obvious from the kind of arguments we've been giving, that why he was against this whole racial formulation superiority of certain races and so on. But that he shared with a number of other people. So even Cavali's Forza, for instance, the other one was very active in similar kinds of endeavor, looking at variations, population genetics, population variations and so on, was again an anti-racist to the core. So there were a lot of other people over here. But what distinguishes Leventine, of course, that he identified himself as a Marxist, and he also called himself a dialectical biologist, which is opposed to a mechanistic biology, if you will, which is what was being argued by a lot of the biologists of that age. And of course, you had also various other variants over there, which went into the racist category when they talked about how to look at population genetics. So will you tell us a little more about how Leventine saw biology, the kind of work it did, and the materialist method and dialectics that he used? How did you look at it and what lessons does it have for us today? So I will leave, Praveer, the analysis of Leventine's dialectic materialism to you. What I will point out, however, is you're quite right. People like Luca Cavais-Forza were certainly instrumental in deconstructing and minimizing the idea of human races as biologically significant. But it's instructive that in a great deal of work that Cavais-Forza, for example, did, Leventine is cited repeatedly as the originator of that notion. So he was very much the first. So that's the first point. The second point is that for Leventine, the argument of diversity and the argument of contingency in biology meant that value was a social construct, not a biological one. This was one of the reasons why he argued so strongly against genetic determinism, against the idea that some genes simply made people a certain way. And certain ways were better in certain situations and worse in other situations and so on and so forth. And he argued very strenuously and quite frequently, very polemically against that idea. And part of that came from this awareness of biological complexity and contingency. Part of it came very much from his politics and his ideology as a self-professed Marxist. So when he wrote about being a dialectical biologist, I'm not certain just how much of formal philosophy of science there was in the book. That's a question I should ask you. But one thing I will tell you, the number of students of biology in Indian universities that I have met over the decades who have cited to me something along the following lines. We were learning biology and I was really confused because what we seem to be being told was that organisms and physiological, biological, biochemical systems in organisms had achieved perfection where optimum. And this didn't quite make sense to me. Multiple students have said this to me. And I couldn't make sense of my discomfort until I read the dialectical biologist. And I think that is as great a compliment as can be paid to a scholar and a public intellectual. I'm going to really take a pass on trying to talk about dialectical biologist and dialectical materialism, which is what he espoused, except to give a very short synoptic view of that. I think you're right that he didn't enter into philosophy of science per se when he was formulating the dialectical biologist. In fact, he and Richard Levine discussed what is dialectics and biology for the first time when they were writing this book, before that they considered themselves dialectical biologists, but they never really talked about what dialectics meant. And if you go by what Richard Levine is saying, it is in some sense an attack on the kind of determinism that the current philosophies of science may be propagating, which is that the parts determine the whole. So kind of naive reductionism, if we will, which he calls Cartesian, Leventine calls this Cartesian, that if you assemble the parts, then you know the whole. If you know the parts, then you will automatically know the whole. So this was completely wrong. That was one element. And of course, this, as we know, as you have delved much deeper into complexities and complexity theories, properties that are emerging out of complexities of interactions between systems, as well as within systems, all of that have shown that Leventine was obvious forerunner in what we have come today to accept. That earlier view was a crude deterministic view, mechanistic view, if we will. The second part of it is that he also looked at the properties of structure, as Satish has already talked about, that you really talk about that it's not something which is just appearing by itself because of one species having a certain characteristic, but the properties emerge out of the interaction between other species and the species within the species, as well as with the larger environment. So this complexity of what you are seeing, if it has to be grasped, then that is where Leventine and Leventine both use the word dialectical to understand this process, which is very different from the 16th, 17th century Cartesian philosophies that quite often govern what we do, that you can understand chemistry if you understand physics, if you understand chemistry, you will understand biology and of course the ultimate issue that if you understand biology, you will automatically understand society. I think this is the biological determinism which you are quite familiar with, which manifests itself whether it is caste, class or race. In all these three, we have heard these often talked about and claiming it to be scientific and I think that's where Leventine's contributions and a number of other people including Google as well as of course Richard Levine who is his co-author and a whole host of others who actually built the theories today which are complexity theories of different kinds, but let's not get into as he rightly said philosophy, let's restrict ourselves in this particular case biology. Satyajit, thank you for being with us any parting words on this before we close. So let me bring this back as an after note to what I started with. Leventine's great contribution was his awareness of levels of organization, that molecular organization had its own rules but did not completely explain supramolecular levels of organization. So organization of cells, organization of cells didn't contributed to underpin but did not completely explain organizational levels of organization and organizational levels of organization underpin but do not entirely explain human societies that you have to interrogate each level of organization by itself as materialists without necessarily being the kind of crude reject reductionists that that you allude to. This was Leventine's contribution. Thank you Satyajit for being with us explaining rather complex issues of biology which of course among the natural sciences I include biology in the natural sciences as perhaps the most complex and difficult ones to understand. This is all the time we have today in our science show. Please do keep watching NewsClick and do visit our website.