Dan Snow's History Hit - Habsburg Inbreeding with Dr. Adam Rutherford

Episode Date: November 17, 2023

One of Early Modern Europe’s most powerful families, the Habsburgs shared a physical trait so distinctive that it came to be regarded as a badge of honour - the large, jutting jaw that was a result of family inbreeding. But that was only part of their physiological challenges.In this episode of Not Just the Tudors, Professor Suzannah Lipscomb talks about genetics, inbreeding and the sad fate of the Habsburgs with Dr. Adam Rutherford, author of A Brief History of Everyone Who Ever Lived: The Stories in Our Genes.This episode was produced by Rob Weinberg.Discover the past with exclusive history documentaries and ad-free podcasts presented by world-renowned historians from History Hit. Watch them on your smart TV or on the go with your mobile device. Get 50% off your first 3 months with code DANSNOW - sign up now for your 14-day free trial http://access.historyhit.com/checkout?code=dansnow&plan=monthly.We'd love to hear from you! You can email the podcast at [e-mail] can take part in our listener survey here.

Hi, folks. Welcome to Dan Snow's History Hit. I often get stopped in the street and they say to me, when are you going to give that Professor Susanna Lipscomb another go on your pod? And the answer is right now, folks, right now. I'm very happy to bring you this episode of our sibling podcast, Not Just the Tudors, presented by the very brilliant Professor Susanna Lipscomb. She is talking about the Habsburgs and not just talking about them, she's talking about their inbreeding. This is such a good episode. You're going to love Susanna and her guest, of course, who is Dr. Adam Rutherford. He attempts to describe how closely inbred the Habsburg family became and its rather disturbing consequences. Enjoy.

Despite being an age that assumed a dubious corollary between outward appearance and inward quality, no one went so far as to call the Habsburgs good-looking. But the Habsburg monarchs shared one characteristic so distinctive that it came to be regarded as a badge of honour, a symbol of membership of one of the most powerful families of early modern Europe. I imagine that as a keen listener of not just the Tudors, you can picture it. The Habsburg chin, or more precisely, the Habsburg jaw. It juts out sharply, pulling the lower lip into a bulbous shape, and is accompanied by an over-large nose.

These were a result of mandibular prognathism, and this trait was caused by an unfortunate family predilection, uncles marrying nieces. In fact, the prognathism was hardly the worst of it, as we shall see. To discuss the inbreeding of the Habsburgs, I'm delighted to be joined by Dr Adam Rutherford. We don't often get to speak to scientists on this podcast, so I'm glad that on one of the rare occasions we do, we've got one of the good ones.

Dr Rutherford is a geneticist at University College London. During his PhD, he was part of a team that identified the first genetic cause of a form of childhood blindness. He's written and presented many award-winning shows, including BBC Radio 4's flagship programmes Inside Science and Start the Week. The Curious Cases of Rutherford and Fry with Dr Hannah Fry is on its 20th series, and he's also presented TV series on BBC Two and BBC Four. He's the author of five books, including Control, The Dark History and Troubling Present of Eugenics, How to Argue with the Racist, and the one we'll be talking about today, a brief history of everyone who ever lived, the stories in our genes. I went to University College London to record with him. Adam, it is a pleasure to welcome you to Not Just the Tutors.

Thank you, Susie. It's a pleasure to be here. Well, I was very excited when you suggested we could talk about genetics and history. And we're going to be talking about the Habsburgs. But I wanted to start with the sad or glorious fact, depending on how you look at it, that we are all inbred. Or put it another way, we all have regal ancestry. Yes, absolutely. It's become a sort of bugbear of mine over the last few years, because of programmes like Who Do You Think You Are?, which is great TV, highly entertaining,

and a good way of accessing sort of personal narratives and stories from histories that relate to individuals. The problem with it, from my tedious perspective as a geneticist, The problem with it, from my tedious perspective as a geneticist, is that it really only represents a tiny minuscule proportion of our total ancestry. So when you identify a notable person in your genealogy, and in that program, it's always if you're a woman, it's always a chambermaid. And if you're a man, it's always a duke or a Nazi. That's the general pattern. But what it does is it fetishizes individuals from history in our historical narratives without representing the fact that all of our family trees collapse and coalesce in on each other. So when we start doing the maths on this as a concept, an idea emerges which we refer to as the iso point or the identical ancestors point, which is the time in history when the population at that time is the ancestor of everyone alive today.

Wow. Yeah, I know. And I've explained this so many times and I still, even when I say the words, I still think, can that be true? But it is. It's conceptually and mathematically true. But it's based on the simple premise that everyone has two parents. Everyone who's ever existed has had two parents, which means that the number of ancestors you have as you go back through the generations doubles each generation, right? So two parents, four grandparents, eight great grandparents and so on. But there's a problem inherent in that, which is if you go back 40 generations and we take a generational time to be about 25 years, 40 generations, 25 years per person is a thousand years into the past. So it means that the number of ancestors that you have as an individual a thousand years ago is two to the power of 40.

And that number comes out as one trillion. And one trillion is 10 times more than the number of people who've ever existed on planet Earth. So it cannot be correct. But the mathematical sneak in this is that you have one trillion positions on your family tree going back 40 generations. But as you go back through time, you find that those positions are occupied by the same people initially, just a few people because we're all inbred to a certain degree. But the further you go back through time, what you see is that those positions are occupied by the same people over and over again, until all lines of your family tree as an individual begin to cross through all of the individuals at a particular time. And when that happens, that's the genetic isopoint. And when

we calculate the genetic isopoint for Europe, which is the best studied population, what we find is the isopoint occurs about a thousand years ago. And so if you can demonstrate that anyone alive a thousand years ago has living descendants today, then what it means is that they are the ancestor of everyone alive today. The name I always use is Charlemagne because he's the first Holy Roman Emperor. We have his lineage. We know that there are living descendants of Charlemagne today because people have done their family trees. And that's a sort of badge of honour. It's kudos in genealogy to have Charlemagne in your family tree. If Charlemagne has any living descendants today, which he does, then he is the ancestor of everyone alive today in Europe. This blows my mind.

I know. Not everyone can prove it. And that's a different question. So when they do, who do you think you are? And they have a paper trail, a proper births, deaths and marriages certification, which goes back through the ages. Not everyone can do that. And so there is still kudos in that process. but if it's true for Richard Branson when he press released this a few years ago or the actor Christopher Lee who was from a semi-royal family Italian royal family it's true for those guys which means it's true for you and it's true for me and it's true for pretty much everyone listening so what we have to imagine is that a family tree almost is a kind of diamond shape, that it starts with a point at the bottom,

but also has a point at the top. Yeah, that's almost right. It's more that it expands out from you as an individual as a tree, then it begins to straighten up, and then the branches begin to cross over. So it's not quite diamond, I suppose, it's just square at the top. When we look at family trees, the way we draw them, nice branching patterns, they're just never like that. In reality, they're never like that because we know that there are crosses over. So for example, five generations back, you will have two to the power of five ancestors, which I can't remember what that number is and I should know, but it's hundreds, right? And half of them will be women

and half of them will be men. But those are just the positions. It's quite possible your great-grandmother is your great-grandmother twice or even three times because she had descendants who had descendants, and then they maybe met, married each other, and you might be married to your fifth cousin. In fact, it's likely you're married to your fifth cousin. Me and you are probably fifth cousins. Being fifth cousins, it means we've got a shared ancestor X number of generations ago. So that person, whoever that person was, occupies multiple positions on our family trees. And that's a few generations back. If you keep going back and back back through time if you get a thousand years every single person is in every position on everyone's family tree so would it be even vaguely accurate to say that for the period we mostly talk about on this podcast 16th 17th century where people get very excited understandably if they think that they have a link to Richard III or Anne Boleyn

or someone of importance in that period. Is it at all true to say, she says carefully to someone who knows about numbers much more than she does, to say that sort of half of the people living may be related to one of those people living 500 years ago? Probably more than. So I did the calculations for Edward III because, and I did it specifically because that was one of the episodes of Who Do

You Think You Are with the actor Danny Dyer. They demonstrated that he was 21 generations directly descended from Edward III. And he was born in the 70s like me. And so one of the things he said, he's very funny and it's well worth watching this on YouTube because as it's revealed, and I think they're sitting in Westminster Abbey and they do this big sort of scroll and roll out and it's got its family tree, the lineage starts with the first Plantagenet and ends with Danny Dyer. And he says, I can't get this into my nut. Fair enough. He said, I'm going to treat myself to a massive rough, which you'll know is not the right time period at all. But the third thing he said is I can't compute this. My blood is his blood. And I was sitting there watching this,

and I was writing a book about this at the time. And I just thought, well, I wonder if I can calculate this. Specifically, can I calculate the probability that anyone born in the 1970s is directly descended from Edward III, as they had demonstrated that Danny Dyer is. And the long and the short of it, and it was a fun project to do with some of my colleagues here at UCL, just a couple of officers down from where we're sitting. And what we worked out using very conservative, we did it multiple times just to test it, but using the most conservative, most constrained possibilities. The probability that anyone born in the 1970s in the UK who is not of recent migration to the UK,

the chances of them not being descended from Edward III are 10 to the minus 21. So as close to zero as it's possible to be. Sorry, this is lovely speechless uh i would bet my house and children and everything valuable in the world that you are directly descended from edward iii probably 21 generations i always knew i had royal blood and that's the thing isn't it we're all special as you, but none of us are special, therefore. That's exactly it. You know, I don't want to poo-poo people's fun with this. Being able to trace it is different from most people. I've done quite a lot of genealogy in my own family,

and it just drops off a cliff in the 19th century for various reasons, one of which is that on one side of my family is via indentured slavery in Guyana from India. And so the records, they literally vanish. And most people's records just fall off a cliff. But it is mathematically and absolutely true that all of those family trees coalesce. But the simple reason is that there are more people alive today than at any point in history. But you have a trillion ancestors a thousand years ago. The simple maths is you've just got to cram those two numbers into each other, and the answer that falls out of that is, well, it's everyone. That's so interesting, and I imagine the paperwork particularly drops off before the introduction of parish registers, which was 1538, and so you've got

details from then. I remember once putting on Twitter, the site formerly known as Twitter, that I had seen a portrait of an ancestor from 1660 who was called Richard Lipscomb, who drowned in Portsmouth Harbour, possibly when drunk. And, you know, it's quite a fine picture, and he's wearing some nice linen around his neck and a fairly sort of modest suit. And the portrait doesn't show hands,

so he wasn't terribly wealthy because he'd gone for an artist who couldn't do hands. And is that a thing? Well, they're difficult to do, aren't they? So the artist would have to be expensive to be able to do them. Anyway, so I put this on and someone said, oh, well, you know, look at you with your la- at you with your ancestors all my ancestors were tilling the fields and I this is one person from my seven time removed great-grandparents or whatever it is like you have no idea about the rest of them

they're probably all tilling the fields as well yeah absolutely so there's a good story that emerged when I was writing this book a brief history of everyone who ever lived which is that my dad's cousin is quite a keen genealogist and he'd done quite a lot of family tree on my dad's side of the family. And they're all northeast Yorkshire and southern Scotland, back as far as we can tell, as the name Rutherford betrays. And then he came across a marriage certificate from 1818, I think it was. And it's between a guy called Benjamin Handy and his then wife, who's described as a savage. On the marriage certificate in Covent Garden, it says savage. Now, Benjamin Handy was the proprietor and owner of Handy's Travelling Circus, which was the biggest

travelling circus of the time. Her name was Mary Huntley, and he had recruited Neil Huntley, who was a Katorba tribesman from the States and was described on the bills as the world's greatest horse jumper. So that's a person who jumps from horse to horse as part of the circus act. You know, we know loads about circus. Circus history is fascinating. And Mary Huntley was his daughter and they got married, right? And she's my great, great, great, great, great grandmother. And I tell this story because that's quite cool. Having a Native American ancestor is quite a cool thing to say. And it was just at the time when Elizabeth Warren in the States was claiming Native American ancestry.

And it's meaningless. It's genetically meaningless. It's culturally meaningless. She is probably the ancestor of tens of thousands of people, if you go that far back. And just because I've demonstrated this link, it means absolutely nothing. And as you just said, identifying her, Mary Huntley, you fetishize that over the other, I don't know how many hundreds of great, great, great, great, great, great grandmothers I should have at that time. We don't know the names of any of them. Just she's one who happens to stand out because the record exists. I drew that comparison in an article. I got in quite a lot of hot water for it.

But saying Elizabeth Warren is saying, I've got Native American ancestry. It turns out I've got got Native American ancestry. It turns out I've got more Native American ancestry than her, where I'm saying exactly the opposite. It doesn't mean anything other than of historical interest. At that sort of remove anyway. Yeah. So there's another fact which is worth mentioning, which is that genealogy and genetic genealogy are not quite the same. And they diverge from each other as you go back through time. Now, I won't get too molecular about this, but everyone has two parents, right? That's uncontroversial. And we inherit all of our DNA from both parents. So you have two sets of

genes in every cell. One has come from your mother, one has come from your father. And it's the interplay between them, which is what makes your father, and it's the interplay between them which is what makes you you. But due to the way that sperm and egg are actually produced in your body and in your parents' and their parents' bodies, the half that turns into you that goes into the sperm and the half that goes into the egg and then they come together and form a complete genome in an individual, it's obviously not the same half every time through generations. And what that means is if you go back through time, we begin to lose genetic information from specific people who are your actual ancestors. And if you go back roughly 10 or 11 generations, what you find is that we carry genetic information from only half of our actual ancestors, 10 or 11 generations back.

They are on your family tree. They are your absolute guaranteed blood ancestors. But you're genetically unrelated to them because the deck has just been shuffled and shuffled until it doesn't contain, you know, hearts or clubs or diamonds. Cards works quite well as an analogy. So Danny Dyer's claim that Edward III's blood is running through his veins may or may not be true. Well, metaphorically, sure, because some of the language is confusing and we talk about bloodlines and that, but that is a biologically meaningless phrase. But it is highly likely that he contains no genetic information directly from Edward III at all. I'm Matt Lewis. And I'm Dr. Alan Orjanaga.

And in Gone Medieval, we get into the greatest mysteries. The gobsmacking details and latest groundbreaking research. From the greatest millennium in human history. We're talking Vikings. Normans. Kings and popes. Who were rarely the best of friends. Murder.

Rebellions. And crusades. Find out who we really were. By subscribing to Gone Medieval from History Hit. Wherever you get your podcasts. So in terms of thinking about collapsing family trees, that brings us neatly onto the Habsburgs. So I thought maybe we'd start at the end, as you do in your book, which is in Madrid on the 1st of November 1700, with Carlos II. So let's talk about him first of all. Yes, he's a deeply troubled individual who's had a torturous life.

And he died on that day, November the 1st, 1700. And I think it was just before his 39th birthday. He's King Charles II of Spain, and he's the ruling Habsburg. And the Habsburgs, they are the biggest ruling dynasty for the last 200 years at least. Five Holy Roman emperors have come out of this one family. The Habsburg Empire is the biggest chunk of land in Europe. And he's the last of them because he dies childless. So no heir.

And what follows is the Spanish Wars of Succession, where Europe is divided up brutally amongst various warring factions. So in terms of thinking about what we know about him and why he couldn't have children, what can you tell me? Yeah, so he was profoundly disabled all of his life, physically and mentally. And this was registered from his birth 39 years before this. He didn't learn to walk or talk until he was less than 10, but very developmentally delayed. The Habsburg jaw, which I think many of your listeners will be thinking of when we talk about any Habsburgs, that sort of really iconic, what we would now call a prognathous jaw, and considered to be a badge of

this divinity in their family, they've all got them. And if you look at the portraits from Philip I, who was, his nickname was the handsome. I don't see it. I definitely think there stands a beauty change over time. Yeah, they definitely do. None of these guys are handsome at all. And many of the women in this family also have this Habsburg jaw. But it's the badge of honour, right? It says we are Habsburgs and we have divine rights. Carlos, Charles II, his is so pronounced and his tongue is so swollen in his mouth that he couldn't retain food in it. When he was eating, liquids would dribble out of his mouth. On his throne in Madrid, he had a little semicircular curtain that the courtiers would

pull around so that they couldn't see the food falling from his mouth. You know, really, really troubled existence. He was the king from the age of 14, but he was rex in absentia. And it was his aunt, Mariana, who really was controlling the throne. And his courtiers, all the people gave him a nickname, which was, now my Spanish is terrible. My Spanish pronunciations is terrible, so correct me on this. It was Carlos el Hequitado, which means the hexed or bewitched. Now, he was married twice and both in private letters, both of his wives, one of them complained of his impotence and the other that he couldn't ejaculate. This fitted in with his overall disabilities and physical problems, but he couldn't produce an heir that's the big issue here even his autopsy is incredible i've got a line from it here which let me just check this because it's

yeah towards the end of his life he asked for his ancestors to be exhumed so he could look at their decomposing corpses just a bit dark a bit weird yep and then when he was dissected, the post-mortem, the quote was, his heart was the size of a peppercorn, his lungs corroded, his intestines rotten and gangrenous. He had a single testicle, black as coal, and his head was full of water. I don't think that's accurate. It feels like a significant amount of exaggeration going on there. Do we have any sense of who the source is and what relationship they have to him? I mean, because it feels like a hostile source. It does, doesn't it? Yeah. No, I don't know. It was a

physician describing his deformities. And the only reason to do something like that and to produce a post-mortem report like that is to damn him. There can be no other reason. There's no use in it otherwise. Yeah, well, I suppose that makes sense if people are trying to divvy up the empire upon his death. So let's try and explain this. Can you talk me through his family tree? Yeah, it's a butte. So we talked about family trees earlier. We talked about how they branch outwards and eventually they collapse. And we actually call that pedigree collapse. And when we're talking about the isopoints, all pedigrees collapse over a long enough period of time. And for a healthy population, you don't want it to collapse too quickly. But what we see in the Habsburgs is

full pedigree collapse over two or three generations, which ends with the death of Charles Carlos. And the reason for it is because the Habsburgs had engaged in profound inbreeding, deliberate, in order to maintain that chint, maintain their power, in order to keep power within the very small group of people. And they basically stopped outbreeding about 200 years before Charles was born. So when you begin to look at the family tree, if you go back five or six generations, you should have 200 to 500 people in your family tree that rule about doubling the number of ancestors you've got and me and you will have probably a little bit less than that because we'll have the same people occupying multiple positions and I always make the

joke that I'm from Suffolk so mine probably collapses more quickly than yours so if you go back seven generations, 256 people on your family tree, Charles has 80, right? So almost an order of magnitude too few people on his family tree. And almost all of those inbreeding events are between uncles and nieces. So you only have to look at the family tree itself, which I know you've seen, but I'll show you. And it's difficult to describe. But you have to kind of see it to talk through it so given that people can't see it we're going to have to explain it very carefully yeah so it's not a tree is the first thing if you imagine an

idealized family tree with it going you two parents they've got four parents and maybe there are some weird loops because people died or remarried or had children out of wedlock or whatever they still just branch outwards. This only contains loops. Is this his whole family tree? This goes back to Philip I, Philip the Handsome, and his marriage to Joanna of Castile. Now, she had a nickname as well.

La Loca. La Loca, yeah. She was the mad. She was the daughter of Isabella of Castile and Fernando of Aragon. And she lived an extremely troubled life as well. I'm always a bit cautious about posthumous diagnoses. Yes, it's so hard to do, but she certainly fell madly in love with Philippe the Handsome. She became Queen of Castile and heeded by her right. But when he died, she carried his body around for a long time and wouldn't allow it to be buried. She was so attached to him. I know a lot more about her mother and her other sisters, but she certainly was a little troubled herself,

I think it'd be fair to say. Charles at the bottom of this tree and his parents are Philip IV of Spain, who was married to Marianna of Austria. Now you follow Philip's lineage back because his father is Philip III, who was married to Margarita of Austria. So Philip III is Charles's grandfather. who was married to Margarita of Austria. So Philip III is Charles's grandfather. But if you go via his mother, Mariana of Austria, and her mother was Maria Anna of Spain, who was married to Ferdinand III, who was one of the early Roman emperors. And Maria Anna of Spain's parents were Philip III and Margarita of Austria. So what that means is that Philip III and Margarita are simultaneously Charles's grandparents and great-grandparents. So his grandmother is also his paternal aunt? No, his grandmother is his great-grandmother as well. I mean, she probably is his paternal aunt

too. We can work this out by looking at the tree. one two margarita is ferdinand ii's sister so yes she's a great aunt as well as being grandmother and great-grandmother and maria anna i was thinking was his grandmother through his mother yes right and also his aunt because she's the sister of his father that's right yeah. Yeah, it's complex. It's complex and mad and really quite distasteful and funny because it's the single most extreme example of inbreeding I've ever come across in the historical record. People talk about it compared to some of the Egyptian pharaohs, but I think the records are much less clear.

We've got a really good understanding of this family. But basically, it's all loops. It's all loops like that. And if you track it back to Joanna of Castile, Joanna of La Loca, what you find is that there are at least, I think it's nine different routes you can get from Charles to Joanna. And so she occupies nine different positions on three generations. Ideally, she would be his great, great, great, great grandmother once. But in fact, she's his great, great, be his great-great-great-great-grandmother once. But in fact, she's his great-great-great-great-grandmother three times,

his great-great-great-grandmother, I think, twice, and his great-great-great-great-great-great-grandmother a number of times as well. So none of this is even vaguely desirable. And you talk about an inbreeding coefficient can you explain that yeah sure so we've known about the family tree for a long time to attribute his abnormalities and disabilities to his inbreeding is not new but 2015 or 16 a team a spanish team calculated the actual metric that we use to measure how inbred people are we call it the inbreeding coefficient. So again, I mentioned that you get half of your genetic information from your mother and half from your father. And ideally, you want them to be different to each other. So your mother's genome contains all of the same genes as your father's genome, but they're slightly

different. And you want them to be as different as possible. So outbreeding results in generally healthier children. And the reason for that is to do with what we refer to as recessive diseases or recessive traits, where if you've inherited a disease gene from your father, say, it can be masked by a healthy version of that gene from your mother. And we call that a recessive trait. So something like cystic fibrosis, you have to have two disease genes in order to have cystic fibrosis. But if you have one and one normal, wild type we call them, then the diseased version will be masked by the wild type and you'll be a carrier, but you won't have cystic fibrosis. So you want to have different sets of genes from your mother and your father in order that the possibility of disease genes emerging is minimized. The problem with inbreeding is you might be inheriting the same genes because your parents are related to each other. So they're

more likely to have the same genes as well. So the metric, we call it the inbreeding coefficient, basically it's a measure of how similar your mother's genes are to your father's genes. And it's basically a percentage. So if a brother and a sister were to have a child together, then their inbreeding coefficient would be 0.25. It means that 25% of the DNA of the child will be identical on both sets from the brother and the sister, because the brother and sister share half their DNA, because they're brother and sister. That's really bad news, because if a quarter of your genes are the same, it means the probability of a disease, a recessive disease emerging are extremely heightened. Now, when the Spanish team

calculated Charles's inbreeding coefficient a few years ago now. They worked out that his inbreeding coefficient was 0.254. So it's more than a brother and sister having a child. Exactly. He was more inbred than the offspring of a brother and a sister. And that accounts for all of his disabilities. It's too much for us to say he had a specific disease, he had a specific syndrome, because that's a quarter of your genes. Cystic fibrosis is one gene out of 20,000. But for Charles, it may have been 4,000 or 5,000 genes that are basically the same. So there's various ways to phrase this, but he was shafted from birth by generations. And this inbreeding started way before Joanna and Philip I

but was really consolidated in this period and he had no chance it was amazing that he lived at all it's amazing he lived till 39 I mean yeah what a terrible hand exactly when thinking about it as cards he was dealt the worst hand that is conceivable. It's an interesting irony, because the intention was to maintain power by inbreeding, by marrying uncles to nieces, which is mostly what those relationships were. But they had a 17th century understanding of genetics. And so the result of that was ultimately to relinquish power permanently. The Habsburgs didn't go away, but that was the last ruling Habsburg as a result of a 17th century understanding of molecular genetics. And presumably, I mean, his fate is awful, but even before that, those sort of statistics when

it comes to inbreeding is also going to result in a number of children dying along the way because of conditions that they've inherited. Yeah, that's exactly right, because what you see is increased infant mortality. So the fact that Charles made it to 39 is something of a miracle because within the same family, the numbers are pretty stark. So between 1527, which is when Philip II is born, and Charles's birth in 1661, they had 34 babies, but 17 of them died before they were 10 and 10 of them before they were one. Now, infant mortality in the past has always been significantly higher, but that compares to the Spanish general rate. These are difficult numbers to calculate, but we estimate that the infant mortality in the Spanish population at the time to be about one in five, right? So it's twice or

maybe three times higher than the general population. And again, that's a huge irony because this is the ruling class, the ruling family, they have all the resources available to them. Whereas the peasants, the subjects of Spain are actually genetically much healthier. The reason I'm fascinated by it, it's not just because that's a cool story and it's just interesting history, but fundamentally, I think that the role of biology in history is sometimes ignored or minimised or not talked about at all. But there's this element to history which occurs at a molecular level in our cells, in our sperm and our eggs, and it plays out on the world stage with absolute authority. The end of this empire is a direct result of genetics.

And I love that idea that you've conveyed, which is that it's in seeking power, in seeking to strengthen themselves, that they weaken themselves. It feels like there's some sort of lesson there for the rest of us. Yeah, and I don't know whether you spotted, but there's a Princess Leia quote hidden in that chapter, which she says to Darth Vader, the more you tighten your grip, the more systems fall through your fingers. And I hide nerdy quotes and song lyrics in all of my work, but there is right in the middle of the hatchbacks is a bit of Princess Leia. Well, thank you very much for talking us through this utterly fascinating

genetic material. And I think you're absolutely right. I think we do overlook this biological component to history at our peril. And I think we've just gone through a period where it's been exposed because pandemics through history have been some of the most significant historical events. If we want to talk about plagues, you know, the Black Death, the Justinian plague being endemic from the 15th century, and indeed is to this day, but we know how to treat it. We very rarely talk about the fact that the plague is a fundamentally biological thing. We understand the molecular genetics of how those genes work in Yersinia pestis and how they get transferred from marmots to rats to us. Again, it's a funny thing that biology is sometimes minimised

in us discussing these global events, but it's right there. Well, I think I might be coming back to talk to you about the plague in the future, but thank you very, very much. Thanks, Susie. And thanks to my producer rob weinberg my researcher esther arnott and joseph knights who edited this episode and thanks to you for listening to not just the tudors from history hit we're always eager to hear your suggestions for podcast subjects so drop me a line at notjustthetudors at historyhit.com or on Twitter at notjusttudors. Also, if you're in need of an extra hit

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