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Ludovic Orlando, "Horses: A 4,000-Year Genetic Journey Across the World" (Princeton UP, 2025)
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Hello, I'm Nicholas Gordon, host of the Asian Review of Books podcast, then in partnership with the New books network. In 2016, Ludovic Orlando, a genetics researcher, embarked on the Pegasus Project, an ambitious endeavor to use genetics to discover the origin of the modern horse. There were plenty of theories as to who domesticated horses first, but Ludovic's team came up with their answer. They emerged on the Western Europe Asian steppe around 4,200 years ago. But that revelation was only the beginning of Ludovic's work as he dug into the genetic origins of different kinds of horses like the Arabian horse, as well as heard how the horse's egg diversity changed over time. His research is collected in his new book, A 4000 Year Journey across the World, published by Princeton University Press. Ludovic is a CNRS Silver Medal winning research director and founding director of the center for Anthropology and Genomics of Toulouse at the University of Toulouse in France. His work has appeared in leading publications such as Nature, Science and Cell. He is a recipient of the American association for the Advancement of Sciences Newcomb Cleveland Prize so, Ludovic, thank you so much for coming on the show today to talk about your book, A 4000 Year Genetic Journey across the World. Tell us a bit more about the scientific project that kind of underpins this book. What was it? How did it work? How could you track the genetic lineage of thousands of years worth of horses?
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Yeah, so thanks for having me, Niklas. So this project started about 15 years ago in my lab, and believe it or not, we tried to answer very simple questions such as where, when, and how did we humans domesticate the horse for the first time? And even though those questions were very simple, they were left with no answers for more than a century, in fact. And this is very surprising because horses have been with us for a long time in our history. They have been very key to us. Like they gave us, you know, speed, and they revolutionized warfare. They also helped us farming more efficiently than we could. So we try already to answer those simple questions because I guess they were already important to understand our own human history. And so what we were trying to do is really try to locate where it happened, when and how. So to do that, of course, we built on more than a century of research, and we saw what failed before us. What failed was pretty much the classical approaches involving archaeological findings, where, you know, archaeologists, they go out in the field and they find stuff, and depending on the age of the stuff they find, they are able to tell you narratives, obviously. But with horses, it didn't work so well because when you go out in the field and excavate some horses, you don't necessarily know if they are domesticated animals or if they were wild animals. In other words, whether we rode them or whether we hunted them and ate them. And so because we couldn't tell those things easily, you know, for a long time, it remained impossible to answer the question. So we tried to use other techniques than just archaeology. And in fact, what we used was genome sequencing, which is the extraction of the DNA from archaeological remains. So you have to picture bones, teeth of ancient horses. And then in our labs, we have the technology to extract every single DNA molecule that has been preserved for thousands of years. You know, there's a world record of the oldest DNA on the planet being around 2 million year old. So clearly, for something that is related to human history, you, this technology will work, probably. And so why DNA in the first place? For a number of reasons, but the simplest is to remind you that DNA is what I get from my parents. Half of my DNA comes from my mom and Half from my father. And so the same goes for horses. So in other words, if you have the DNA, you can tell of every single horse, you can tell who was the mother and who was the father. And. And if you do the same with the father and the mother, then you could learn about the grandmother and the grandfather. So, in other words, if you do that through time, using the archaeological record, you are able to follow genealogies, families of horses, back in time. So we try really to use genetics, DNA sequencing, to replay backwards in time the genetic movie of the families of horses and how did they unfold until the present time. And by doing this exercise, really, we could actually start from today, the modern world, sequencing the DNA of horses around the world. Those you have in the us, those I have in Western Europe, and those they have in East Asia or Africa, actually. And little by little, by moving backwards in time to the 19th century, 18th century, 15th century, and so on and so forth, then you are able to tell which horses are related to which. And so you can track down the very early family, the earliest, the one from which all the DNA that is moving around in modern horses actually shaped, was shaped. And so by doing this, we found the answer to the where and when question, which were somewhere around 4.2 thousand years ago. So more than 4,000 years ago, somewhere in the northern range of the Caucasus Mountains. So we are in the region that we call the southwestern Russian steppes today, not so far from Moscow, actually, probably 500 kilometers southwest of Moscow. And so you realize with those answers that perhaps the answer is as surprising as the existence of the questions in the first place. 4.2 thousand years ago, this is a blink in historical time, right? 4.2 thousand years ago, there were already some Egyptian pyramids around. There were cities that were built and other, other animals, such as, if you think about other animals, such as, I don't know, for example, dogs, they were domesticated at least 15,000 years ago, when we were still doing hunting and gathering around in the late Pleistocene. If you think about cows, it's probably 10,000 years ago. If you think about pigs, it's 9,000 years ago. And so what we learned was really surprising. Not so much the answer about the where and the when, but to discover that it was so late in our own history. You know, our species emerged about 300,000 years ago, and we only had the horse for the last, say, 4,000. But no matter how surprising and recent this answer is, you know, we realized that the minute we got the horse, nothing was the same anymore. You Know, because they gave us speed so we could travel the world faster than we could ever in the past. And they gave us the capacity to probably do more efficient wars, killing your enemies more efficiently. Because imagine yourself on the horseback and myself on foot. I will not survive long if you charge me. So basically, even though this revolution took place 4.2 thousand years ago, the minute it took place, the history of humans, human history with capital H actually has changed dramatically.
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C
As part of your book, you kind of run through some of the common theories that have been banded about for the origins of the horse, like the bow tie or Przewalski's horse. You know, what did you, like, what was your kind of approach to investigating these different theories of the horse's origin and kind of what did you find out in your investigations?
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Yeah, so, you know, so the world is very big indeed, right? So we, since we had no clue about where and when, we had to look for pre existent theories. You know, what other researchers published in the past and indicated what could be the answers to those questions? And there were indeed a bunch of theories around. The one that was probably the most famous and the most, I would say, consensual in the scientific literature was claiming that horses were probably domesticated somewhere in Central Asia, in the country that we call today Kazakhstan, somewhere around 5.5 thousand years ago, which is actually more than a thousand years before the date that I just gave you. And this theory emerged for a number of very good reasons, archaeological reasons, mostly, right? So if you go at the Botai site, which is the site where those horses and people were found 5.5 thousand years after they died, you realize that you have a village there. So people were living in houses, and near the houses you had some enclosures. Those enclosures were mostly only having horses around, simply because the only animals, or almost the exclusively found animal on site was horses. By that, I mean that archaeologists have found more than 300,000 bones at Botai, and 99.9% of those were horses. So clearly there were people and horses around at the village that we call Botai, 5.5 thousand years ago. And simply for these close proximity of both species, us and them, people have made the theory that, you know, we probably had domesticated them because we were so close. But there is more to this theory. You know, if you look at the teeth of those horses, you realize that they have some damage, especially at the second premolars. So these are the te that are pointing forward on the horse mouth. And this is right where we normally place a bit to control horse movements. So if you see a bit damage on the surface of the teeth, it may indicate indeed that those horses were actually ridden, controlled, at the very least, harnessed, for sure. And there is also something else that archaeologists have found, which is that if you look at the ceramics of those people, so, you know, not horse bones these times, but actually tools that people prepared at that time, you realize that at the surface of some pottery, ceramics, you find some dietary remains. So the food remains of what those people ate at that time, and if you do the chemical analysis of those food crusts, you realize that they were made of horse milk. In other words, Botai was a place where you had tons of horses living near houses, in enclosures, with signs of them being controlled through chickpea or bits that they placed in their mouth. And also we drank their milk. So that was a sort of smoking gun for domestication, to be the first domesticated center of horses ever. So we went there to try to, you know, speed up our project, because if that was the mainstream theory, then by going there, we will actually wrap up the genetic movie directly from the beginning. And we went there, it was 2014-15. We sequenced a number of genomes from there. By genome, I mean the whole DNA that we can analyze from each individual horse, which represent a huge amount of information, about 3 billion letters of genetic letters. So lots of letters, lots of words, lots of information. And by doing that, we did the DNA comparison of that DNA to the DNA of horses today. And we were really surprised to realize that none of the horses that we call domestic today, those you have in the us, those we have in Europe and anywhere else in the world, none of them descended from that bowtie horse family. So it means that clearly, what was the smoking gun of horse domestication was not the smoking gun we fought. It could be. And in fact, we could demonstrate that those people at Botai did domesticate the horse. We know that because we drank their milk, we control their movements. But surprisingly, those people vanished at some point, and so did their control. For horses, if people disappear as often in human history, then if they have no legacy to the next generation, then what they invented, the innovations are lost. And that was true for horse domestication. So what we learned was that there was a first domestication process starting in Central asia somewhere around 5.5 thousand years ago. But within a few centuries after that, the people doing so disappeared. And therefore, that horse domestication process was lost and ended. It was abortive to some extent. Those horses survived and went back in the wild. They became wild again, if you will. They were feralized somehow and they survived until today. But not as domestic horses, but as what we call the Przewalski's horses. The only horses that we fought was the last truly wild horse living on the planet. So that means that that first domestication process stopped. And so the domestication process that I mentioned earlier, the one started 2.2 thousand years before the Common Era, 4.2 thousand years ago. This one took place somewhere else, as I said, in southwestern Russia. And this one was the one that actually made emerge all the horse families of domesticated horses until the present extra value meals are back. That means 10 tender juicy McNuggets and medium fries and a drink are just $8 only at McDonald's for a limited time only. Prices and participation may vary.
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C
So maybe you can get into that story a little bit more. So like how then did the horse spread from this location, Russia, then around the world?
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B
Yeah, that's fascinating to realize how quick they went out of the domestication center. So you imagine a small part of the world where those people at that time 4.2 thousand years ago, did breed this new horse bloodline, the one that we will call the domestic horses from now onwards until the present day. And that location was very small indeed. A few hundred kilometers only, you know, but east to west and north to south. So not even like, not even a country, like really a sub region of, of a small country. But then in the next 200 years, so less than two in, in about two centuries, you realize that those horses that were only in this small region, actually you find them thousands of kilometers apart. Within 200 years you have Them in Asia, in Kazakhstan, you have them in the Altai Mountains, which is near Mongolia, if you will. In Europe, where I live, you have them in Germany, in France, and even in Spain, within three centuries at most. So it means that even though only a few people invented this modern bloodline of horses, that bloodline was massively successful. Most of the people at the time seemed to want to acquire that bloodline. You understand why? Probably because it gave us the people who will buy this new horse, new commodities. We could travel faster, we could make war more efficiently, and so on and so forth. And the minute your enemies have that horse, well, you have no choice but having the horse yourself again, because otherwise you will be actually defeated at war. So you realize that there was a sort of vicious circle where people without that horse bloodline had to acquire it pretty fast as a sort of new and central critical innovation for their own survival, if you will. And so that's why we see this very small bloodline that emerge in a tiny bit of the world, become global in only a few centuries.
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C
So you kind of dive into some of these, you know, more specific stories about the horse. And one of them is, is kind of the origins of the Arabian horse. Kind of. What did this project tell you about? About that?
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B
Yeah, so the Arabian horse is one of those, you know, very, very, very fascinating breeds of horses, you know, probably some of the most famous around the world, with the quarter horses or the Thorbrides, for example. And what is key about the Arabian horses is that they are some of the most resistant or resilient horse breeds in the world. If you actually race with an Arabian horse, you don't race for a mile or two as you do with the quarter horse or with the Verbreds, but actually you will race for 100 miles, 160 kilometers. So these are horses that are able to gallop for a really long time, for really long distances. Indeed. Right. And that, of course, was a sort of asset that many people in the past wanted to acquire. So in our data, when we replay the genetic movie of horse domestication backwards in time, we see the emergence of the Arabian horse bang on around the emergence of the Muslim religion somewhere in the range of the 7th to the 8th century of the Common Era. So not so long ago, somewhere around 1.3 thousand years ago, if you will. But what is really cool is that that bloodline emerges somewhere in the east, probably in the Middle east, or probably around Iran. We don't know exactly the location, but what we see precisely is that the Genet influence of that bloodline spreads really fast again. So in a few centuries, for example, by the 9th century CE, we see these bloodline that we call the Arabian horse expanding in Europe, in Western Europe, in my country, in France, and in Spain, not far from here, we see also the same bloodline expanding into Asia. We see that bloodline expanding from Iran into Central Asia, Kazakhstan again, and expanding eastwards towards Mongolia. So you realize that this phenomenon of a new horseball line being bred somewhere by some people because they were selecting for specific traits, specific capacities of their horse, they could spread as a new innovation that a lot of other people around the world, around the world wanted to acquire simply because it made their life easier, or it made their war making better, or it made their, you know, whatever they wanted to do with the horses more efficient to some extent. And so we realized that probably, you know, the. The Arabian horse has been some of the most genetically influential breeds that we ever bred.
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C
You know, another thing you get into is. Is. Is. Is how the modern horse spread outside of Eurasia, like, particularly to the Americas. And you talk about, you know, this idea from the Americas that the horse was actually there a lot earlier than I think the current historical narrative thinks. And you also kind of dive into that as well. I mean, again, what did this project tell you about when the modern horse kind of first made its way to North America?
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B
Yeah, so that was a fascinating story for us, too. And we actually studied the answers to those questions for more than five years, in fact. And what I stress is that this question was not just important to solve for people interested in horses. In fact, you know, it is dramatically important to understand how species adapt to climate change. The reason why I'm saying that is that you had, in northern America, horses around a long time ago, in fact, the history of the horse, not the horse as a species or as a domestic bloodline, but as a group, as a family. We call the family the equids. In biology, this story started in America, in Northern America. So, in fact, without America, there will be no horses around, basically. But it was a long time ago, 55 million years ago. But even more recently, you have the horses in Northern America. You had many of them, actually not one type, but very different flavors. Actually, we give them tons of different names. We being the paleontologists, right? Those people who are looking around for bones and fossils and studying their morphology, and they are able to tell you, oh, this looks. It looks like a horse or it looks like something else. Okay? So they can tell for sure that there were horses around of the species that we call the horse up until at least 13,000 years ago in Northern America. There is no doubt about this. So the first answer is to tell you and to remind you that for sure this is a no brainer. There were horses around 13,000 years ago, up to 13,000 years ago in Northern America. So there was no doubt about that. But we wanted to compare those horses to the horses we find today, not only in America, but actually somewhere around the world. And so, for sure, I said that it was important to solve that question for understanding how climate influences the evolution of species, because somewhere around 19 to 26,000 years ago, we were at the top of the Ice Age. So that means that the ice cap in Northern America was actually covering a large chunk from the Pacific to the Atlantic. Basically there were thousands of kilometers of ice west to east, stopping the expansion of any kind of population further south, basically. But somewhere around 19,000 years ago, the climate changed. And that means that the ice cap started to melt. When you have a lot of water in the ice, you know, in the ice cap, it means that there is a lot less of liquid water in the ocean. So that means that the sea level is actually lower. So that means that when there was ice caps, the sea levels were lower. So people. And so horses could actually move on their feet from Eurasia into America or from America into Eurasia. This vast land bridge that existed during the time of the Ice age was called Beringia. Right. It's so much a large area that we gave it a name of a continent, Beringia. It was large indeed. And so studying the horse in Northern America somewhere around 13,000 years ago and before tells you how often populations of horses could naturally cross Beringia, go from Eurasia into America, and the other way around, basically. The second thing that was really important to study here is the link between these population that lived until 13,000 years ago in North America and the horses you can see today in America. Why is it very important? For a number of reasons. I can actually stress two. One is because there is lots of first nations in America who are horse people. By that I mean that their life ways are really intimately linked with horses. Basically, I'm thinking here about obviously the Lakota, the Styx, the Comanches, for example, and many more, obviously. So understanding how their horses relate to the horses that was around 13,000 years ago is a way to better understand some of the first nation and the emergence of their lifeways. The other reason is that from the 16th century onwards, there were the Northern America and the Americas in general were colonized basically by European settlers, right? So those people also brought horses in America. And so do you have horses today in America that more relate to those horses you had 13,000 years ago and before, or do you have, on the contrary, more horses that descend from the colonial period, horses that we brought from Europe into the America? And so to answer those questions, what we did was, of course, using DNA, because DNA is what I do for a job, you know, sequencing DNA. But more than that, we also developed very, very deep collaborations with a number of first nations, including Lakota and many more, to really understand with DNA and with anthropology, what was the role of the horse in those population and in the America in general. And so so far, what we found is that that the horses that we brought from Europe was actually used by first nations very early on, by already the end of the 16th century, and not, as we thought before, using historical sources from 1680. So what we learned, that first nations could use horses from a colonial descent. So horses brought from Europe, they could use them and develop their lifeways on that type of horses in almost a blink, you know, 80 years at the latest, after the Americas started to be colonized, which is mind blowing. Actually. The second thing that we learned is that from the number of horses that we sequenced from the 17th century, 18th century, 19th century, and the present day, we realized that the horses that were in the Americas early on, say during the 17th century, 18th century, they were pretty much Spanish in terms of their genetic ancestry. In other words, they came with the conquistadors. But what we also realized is that if you push the genetic movie forward in time to the present day, so say the 20th century, you realize that the horses you have in the US right now, as I'm speaking, are a lot more British in origins. In other words, you see that the horse DNA reflects the two main colonial powers that were actually ruling the Americas. First, the Spanish power, the Conquistadors, and then later on 19th century onwards, the British settlers who brought with them many, many horses. So much so that they rewrote the genetic landscape of the America a second time. The third thing that we found was that those horses that were around 13,000 years ago, we don't see their genetic trace in horses that we have sequenced in the 17th, 18th, 19th and 20th century. So we are very cautious with this conclusion, and I'm very cautious with this conclusion in the book. I'm saying that so far there is no direction, correct evidence of any survival of the horse that was in the America in the beginning more than 13,000 years ago, and it seems that it has been replaced by those colonial horses. But at the same time, when I work with my indigenous colleagues, they remind me that obviously paleontology hasn't excavated all of the Americas. And they remind me more importantly that paleontologists have not excavated sacred indigenous sites. And so imagine that there will be some sacred indigenous sites with horses that were preserved by indigenous people. Obviously our data will not have picked that up. So that's why I'm concluding in the book that what I'm telling you right now is a working model. And we keep working on this, we have together with the indigenous nations to try to really see if there is more to this narrative.
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C
So I wanted to kind of dive into another question you deal with in your book, which is kind of the mule. I mean, why did you want to focus on this kind of hybrid between a horse and a donkey?
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B
Yeah, that's surprising. My chapter about this is called the Other Horse and by that I mean, that mules are, you know, a sort of animal. I don't know about the US but certainly in my country, in France, they have a bad reputation. Right. When you tell someone that that person is a mule, it means it's dumb. Right? It's really a very thick person. So we think about this animal, which is half horse, half donkey, in a very negative way. And yet this is true today. But in the past it was very different. Because if you travel back to, for example, the Roman times, so somewhere around 2,000 years ago, you realize that in this empire there were already two types of equids that the Romans were using. They were using horses, for two thirds of their animals were horses, but one third was the mule. And the reason is very, very simple to understand is that if you get close to a mule, you realize that they have the qualities of both their parents. They are as quick as the horse, but they are as resilient as the donkey, basically. So that means that when you have a mule yourself, you don't need to feed them too much, you don't need to give them water too much. So it means that managing them cost less than managing a horse or managing a donkey. Right. And yet they have very, very strong stamina. So you could actually ride them for hundreds of kilometers. So why Romans wanted to have them so much? Simply because the Roman Empire extended from Rome in Italy to even the uk, basically. Right. So that means that it was a thousands of kilometers wide empire. And obviously it came with a logistical nightmare. You had to distribute weapons, goods and more across the very wide area. And so we didn't have cars at that time. Obviously neither did we have planes. So what was really convenient to use is an animal that was actually very resilient and very capable for not so much food and water to actually run around for hundreds of kilometers. And that animal was the mule. So you realize by just looking at this example how critical mules have been and what was the role they have played in human history. Well, a very big role indeed. And if you go back for two seconds to the previous topic, the colonization of the Americas, well, it's there true as well that mules have been used a lot to travel across the west plains of America. In fact, one of your first presidents was a mule breeder himself, basically. Right. So it means that today we really don't give justice to this animal. And so that's why I felt compelled to sort of write a chapter to actually give justice to help the number of services that this animal gave us during our own history.
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C
So, I mean, humans certainly think, I think quite recently have, you know, they've tried to breed kind of stronger, maybe like, definitely faster horses for things like recreation purposes and stuff like that. You know, like, what does that look like in the genetic record? And kind of what has that meant for the genetic diversity of the horse?
- [37:58]
B
Lots, actually. So you're very right. So when you breed horses, you have pretty much two options, and they are not exclusive. So on the one hand, you can actually mix some ancestries, mix some bloodlines. You know, for example, you like the quarter horse and you like the Arabian horse. You can mix them together, they have babies, and those babies will have the qualities of both. So that's one option. We call that process admixture. The other option is that you stick with your bloodline and you will actually select for specific things you like a lot. For example, imagine that you want to have a larger horse. So, for example, you will at that generation select only the tallest ones and make them have kids together with the expectation that the next generation will be on average, a bit larger and so on and so forth through generations. So when you do the letter that we call artificial selection, artificial because we humans decide, but selection because we select only a subset of the horses. You realize by this process that, well, not all the horses are eligible to reproduction. Some will never pass on their genes to the next generation because we didn't select them. So naturally, when you select, you will locally reduce the genetic diversity of horses. Your gene pool was diverse at some point in time, but at the minute you will start sub selecting only a few lucky fews, then you will have a loss of diversity. And so what our work has shown is that in the last 200 years, really, the last 200 years is really the last bit of horse domestication. It started more than 4,000 years ago, you know, so more than 40 centuries ago. I'm only talking now about the last two centuries. Well, in those two centuries, there's been a huge loss of genetic diversity because breeders have started more systematically than they did earlier to select four specific types of horses, precisely those types that we call breeds today. The, you know, the fur breds did not exist before 1721, actually as breed. So that means that in the last 200 years, this process was done in the expectation to have faster horses on one hand, or taller horses on the other hand, or stronger horses for another population. That's true, and we manage very well to do so, but at the price of a dramatic loss of genetic diversity. In fact, our Calculations show that globally this is about 16% of the horse genetic diversity that has been lost in 200 years. So that's a very significant amount. The second thing that we found is that not only did we lose some of their diversities because of the process of artificial selection, but at the same time, we reproduced animals that were related with each other. We call that process inbreeding or breeding in, because you take related animals and you make them have kids together. That's very efficient to, to propagate a trait to the next generation. Imagine that mommy horse and daddy horse are tall. Well, chances are that baby horse will be tall again. So you will propagate the trait faster and faster and faster if mom is related to dad, in fact. Right. So in humans we don't do that, obviously, but in the breeding industry we do that a lot. And this is how we propagate traits from generations onwards. And so by doing that, we created consanguinity in the horse population. And consanguinity is able to fix traits rapidly, but with a price. The price that if one of your related ancestors carried a bad mutation, a mutation that will make you sick or less fertile or developing some genetic diseases, chances are that that mutation will propagate very fast as well in the descent. And so that means that this process had a very strong advantage to propagate some traits, but at the same time, it had a cost, the cost of propagating some genetic diseases faster than it would have in the natural settings.
- [42:32]
C
This kind of gets at my next question, which is, you know, we don't use horses for very much anymore. We use them for recreation, we use them for entertainment, you know, horse racing. Sometimes we use them for, for work. You know, I guess they're used in law enforcement and search and rescue and maybe a couple agricultural uses still. But for the most part, I mean, the use, our usage of horses has gone way, way down, you know, and given kind of the, the trends you've talked about, I mean, what do you see as the genetic future of the horse?
- [43:05]
B
Yeah, that's a very good question. Sometimes I'm worried about this, right? I mean, if we stopped this conversation at the previous question, I mean, it would be sad to some extent, right, Because I just said that we lost tons of diversity. And since we are using them even less today than we did 50 years ago, it will mean that they are doomed to actually disappear or to lose even larger fractions of their diversity. And obviously this is not a very appealing future, a future without, without that animal, because that animal has Massive skills that can help us, you know, even with therapy. I mean, some kids are actually cured from their mental disorders by being close to horses. So clearly we don't want to lose that animal for a number of reasons. And every one of us will have their own reason seasons. The future looks there. There is multiple futures for the horses. One that has actually started to emerge is obviously there is a future for the horse industry. Obviously, I mean, the horse is a money maker, so clearly this industry is not doomed. As long as people would love to keep betting on horse races, obviously there is a future, but that future only includes the fastest horses or those with the strongest stamina and so on and so forth. So this is not a future for every random horse. Basically. At the same time, there are other sports than just racing where horses are used. I'm thinking about polo, for example. And so those horses are not too much at threat. What the reason why I brought polo horses here is that in the polo industry, they started to do breeding in a slightly different way. What they do today is that they can actually breed their horses their standard way. You know, you cover mares, where stallion will cover mares and they will have babies together and the next generation will be sired that way. But at the same time, they also started cloning horses. It means that if you have a horse you fancy, and I'm taking here the example of Alberto Cambiaso, who was the multi year world champion of polo, he had horses that unfortunately died very early in their life, but he managed to actually recover some cells of those horses so that they could be cloned. So their genetic copies, in other words, could be brought back to life to some extent. And so today in the polo industry, you have full teams of horses that are full teams of clones. It's the same horse that has been actually cloned many times and that can run in the top competitions around the world. So wait a second. So if I tell you people are cloning, you know that cloning is being a copycat, a genetic copycat, right? So that means that genetic diversity will be even doomed. Further. Right. If all of the horses descend from one and not from many, most of the diversity will be lost. But where they have a point doing so is that if you copy a horse into a clone, imagine it's a female. Well, that copy of this individual will have, every year, two possibilities to be pregnant. Each of the mares will be available for carrying a new generation next year. So that means that you can actually multiply the number of combinations of crosses between a stallions and the same mares, between a number of stallions and the same mares. So by doing that, the hope is that you will create what geneticists call recombination so that you will reassort the genes of the dad with a new reassortment of, of the genes of the mare, of the mother. And this reassortment, maybe you think about a sort of, you know, two glasses of different drinks and you will shake them in different proportions and maybe you will end up with a different copy of the next generation. And so this particular process can actually help preserve some, some diversity over time. Especially so if some people add to cloning genomic editing. So what genomic editing is, is simply the technology that can change some genetic letters in the DNA text. So there are three billions of letters in the DNA of a horse, by and large, you can change a few dozens of those letters. And so if you erase the original letters and bring some different letters, you change the text so you create mutations, so you re inject some kind of diversity. So where that will be important to do in the future? Well, the answer depends on who you are. If you are working for the industry, the answer is going to be, oh, we want to change those letters so that the genes will make the horses faster. Right. For example. So that would be one sort of answer. But long term, if you do that, they are going to be all copycats of the same edited version of the clones. Right. So it doesn't solve our problems of genetic diversity loss. But if you are someone who is more interested in preserving the diversity that is around, well, maybe those letters you want to change are those precisely that have a higher chance to make the horse genetically sick. Those deleterious mutations I mentioned earlier. Right. So you can imagine a world where genomic editing will be used to remove some bad mutations that are present in some horse populations so that the descent will be less likely to develop genetic disorders. So that will be a possible future, a very technology driven future for the horse. But I guess there are many regions around the world where those tools are not affordable or not even available. And so in those countries where horses are still very important, I'm thinking about Mongolia for example, or Kazakhstan or any other country with horse peoples. Well, clearly the future is going to be a sort of wise management of the breeding as those people have done for centuries before the so with that.
- [49:49]
C
I think that's a great place to end our conversation with Ludovic Orlando, author of a 4,000 year genetic journey across the World. Ludovic, I actually have two final questions for you, which are where can people find your work? Not just this book, but all of your work. And what's next for you? What do you think the next project might be?
- [50:08]
B
Yeah, so my work is generally published open source in scientific journals such as Nature, Science Cell and other journals. So I invite all of your readers to really search on the web and cross my name with horses and any of those journal, Nature, Science Cell, and they will find scientific work relating all the findings we had. We keep publishing on horses every year, obviously, because no matter how many questions we solve, there are still many puzzles that remain to be solved. And so that brings me to the second of your questions, which is why, what is it we are doing now? Well, tons of things related to horses. Unsurprisingly, I'm very interested in understanding the role that horses have played in the emergence of the first step empires in human history. So about 2.2, 2.3 thousand years ago, in a territory that we call Mongolia today, north of China, you have those people that we call the Kyungnu, who developed the first step Nomad empire before Genghis Khan, more than 1.5 thousand years before Genghis Khan. And with the emergence of this empire, of course, there is a new polity that emerged, a new state form, if you will. So we want to understand how horses helped people develop new states, new ways to live together. And at the same time, when people develop the first step empire, you have the emergence of the first Chinese imperial dynasty. We call them the Qin. It's about the same time. And so you have a situation in which the Horus probably participated to the emergence of two main political powers in East Asia, the first Nomad empire and the first imperial dynasty of China. We don't know exactly how that took place, and we certainly want to dive in and understand that. And I'm very lucky to let you know that the European Union has been very generous to us and three other labs in Europe, one from Oxford, one from Germany in Mainz, and the other one from the British Museum to give us a lot of money to be able to study those very questions until 2029. So stay tuned because we're going to report our findings in the forthcoming years.
- [52:51]
C
So you can follow me, Nicholas Gordon on Twitter ickarigordon. That's N I C K R I G O R D O N. You can go to asianreviewbooks.com to find other reviews, essays, interviews and excerpts. Follow them on TwitterReviewsAsia. That's reviews, plural. And you can Find many more author reviews at the New books network and newbooksnetwork.com we're on all my favorite podcast apps, Apple Podcasts, Spotify, rate us, recommend us, share us with your friends, support us interviewing those writing in, around and about Asia. Stay tuned for more news coming up on the show. But before then, Ludovic, thank you so much for coming on the show today.
- [53:22]
B
Thank you for having me.