 Hello and welcome to NewsClick. Today we are going to continue our discussions of the last two decades of advances in life sciences. We're going to discuss what has always fascinated us. The origin of life and has the last two decades meant a significant difference to understanding how it arose, when it arose and how do we explain some of the features of life. We have with us Dr. Satyajit Rath who is going to continue our two decades of the advances in life sciences. Okay, I think we sort of now want, I want to take you to another area, which has also seen some development, some thought, maybe not as much as there should be for the 20 years, origin of life. Now, I think we are, all of us are convinced origin of life does not need divine touch, crisper or otherwise. So the question is that it started by saying, okay, from a chemical soup, we can get life. But there have been various approaches taken. Some of that starts with complex system theory, the argument that complex theory shows that from systems which become complex, you can see new properties. And therefore, if certain conditions are met, you would get the evolution of life from that. The primordial soup, biological chemical soup to the evolution of the single set. Is there anything which is new in this or are we still at the realm of different theories? So we are going from the future directions of life to tracking the past directions of life. And it's interesting that over the past two decades, a fairly large number of old ideas and experiments are being revisited and shall we say, firm them. So all of them hypothesis and so on. Absolutely. Famous conjectures. So let's remind our listeners about what the problems are in explaining the origin of life. The first problem is how from the really simple compounds, small simple compounds of the chemistry of the Earth's origin, you get complex compounds. And that problem was solved or was at least addressed interestingly a long time ago, that in under extreme conditions of temperature and pressure and electricity and so on and so forth, you can get what are called organic compounds. So the generation of organic compounds is no longer thought of as a major limitation to the origin of life. In a variety of ways, simple, but clearly organic compounds are part and parcel of exobiology or astrobiology as it were. Ammonia, for example, being the most obvious and striking one, but urea has been another. The really vexing problem has been therefore, how do you, what are we thinking of as life? And life is something that copies itself and therefore grows and propagates. And this concept of copying itself, we've always thought of in terms of cells. Our bodies consist of cells, bacteria are individual cells and all cells grow, copy themselves, divide and become two that are pretty similar to the original one there was, but now there are two and then there will be four and so on and so forth and therefore they will grow. And that's a basic characteristic of what all of us tend to think of as life. What we have done over the past couple of decades is go from the idea that we need cells that copy themselves to saying, we can think of molecules, large compounds copying themselves. And what we were talking about earlier in terms of genetic engineering and biotechnology and the Cas9 CRISPR systems, and so on and so forth, there's an interesting cross-top at the level of understanding how DNA, RNA copy themselves, being able to do self-free copying of DNA and RNA and then thinking, can this happen quote naturally unquote under any conditions. Now copying is a biological process of large molecules, genetic sequence chains. And these processes are therefore not easily going to happen unless they are catalyzed. And catalysis was therefore a major limitation. And that was addressed interestingly by finding that RNA is both a template for copying, but unlike DNA, RNA can also serve as a catalyst for copying. And this has been over the past couple of decades, the basis of the idea of the origin of life being an RNA world. And over the past 20 years, in fact, over the past decade, the really interesting work that has come up is in beginning to establish how in early earth conditions of extremely element rich, extraordinarily hot water in slow sluggish flows at hydrothermal vents, for example. You can imagine conditions where RNA compounds can circulate between areas of slightly lower temperature and slightly higher temperature. And therefore function to catalyze their own copying, function to attract in such flow situations. And the physics of this has been very interesting in these kinds of situations, begin to acquire the spontaneous self-assembly that can lead to sort of proto-cells and therefore begin the process of life. So in a variety of ways, the origin of life through these incremental processes subject to Darwinian ideas of evolution are far more credible today. They're not entirely explained by any means, but are far more credible today than they were 20 years. You know, it's interesting because what we can talk about Darwinian evolution, in fact, which was once upon a time a definition of life, what we're talking about is between the cell where we can talk about Darwinian evolution to what you talked about as the organic compounds which can, we know, evolve naturally. There is a whole set of things which you don't see the Darwinian evolution in this sense, but you see reproduction, ability to reproduction, forming of units. So there is a whole chemistry which seems to be developing which Oparin was talking about, the primordial chemical soup kind of thing. But this is the chemistry which is now beginning to fill the space and it seems to be much more complex than what we thought. The second thing, and this is what I also would like to sort of bring you to, that when I was looking at, for instance, angles and dialectics, one of the issues is that dialectics, and this is what angles does point out, that says complexity gives rise to new properties. He didn't phrase it in this way, but that's how we would phrase it today. And this is also what actually Holden was saying, that one of the things is the evolution of new properties which is today what you call complexity theory, that if you have a certain complexity, you see new properties arise. So that is one part which makes it interesting for me. And the fact what you said Oparin Holden coming back into some mainstream form again, we have sort of stopped talking about Oparin for some time and I see again reference to his literature. So this is very fertile and rich area which seems to be developing, which of course hasn't received much of an attention till somebody says, I guess the Eureka moment, that yeah, this is it. But you have various hypotheses which is floating around. One of them you said RNA and event hypothesis, there have been few others as well. So the interesting moment of research after 20 years, you think we can say we are at least not there, but at least by much better idea of where we should be. So I agree entirely. Let me make two hopefully interesting caveats. One is, in fact, the work of the last 20 years on self-copying molecules, self-copying compounds has the remarkable possibility of extending ideas of Darwinian evolution into this sub-cellular purely chemical work. And that's a whole interesting direction that I'm sure many biologists will be working on for quite some time. And the second point that I would like to make for our audience is this notion of where did life originate is actually only half of the truly fascinating question. The other half of the question is, how the hell did it originate only once? And not repeatedly following related but distinctly different rules. Because keep in mind that many of the basic rules of life, the number of DNA and RNA constituents, the idea of the triplet code, the all of these are held in common across all branches of life as we know it. Clearly that suggests that we're all descended from one statistically unique original event of a self-copying molecule. And yet, really chemistry should be able to imagine other ways of self-copying molecules. How did this work out so that we are, in that sense, unique remains an extraordinarily interesting question. So to phrase it a little more provocatively, the question is not simply how did life emerge, the question is also, and why did it then stop? Not alternate life forms. You know, Satyati, you are in the risk of creating just like the Higgs boson became the got particle of also the God moment of biology. And always keeping in mind that God for biologists is very much a reality as an acronym. It stands for generation of diversity. That didn't do well. I'm sorry, Satyati, I think Higgs boson was a much better got particle than what we just said. On that note, Satyati, we are going to let you go today, but we do want to come and this time and again, bring you on to more, shall we say more distant questions, not exactly how do you look at this vaccine and that vaccine and this particular variant of this virus and that particular variant of the virus which is in the front page of the news every day. And that, of course, we'll continue to discuss on our every Tuesday chats. Thank you for being with us. Do keep watching NewsClick and do visit our website. This is all the time we have today. We hope to be with you again on these and other issues.