New genome of ancient human; 95% of us have a dormant virus that causes disease; Formula E cars faster than F1; Bill Bryson joins the pod!

0:01I'm not giving up. I am selling the building. The final season of FX is the Bear. The restaurant is flooded. Everything's either going to be okay. Or not. We are outgunned and we are outmanned. We have each other. FX is the Bear. The final season. All episodes now streaming on Disney+. In what has been described as a bombshell finding, this week we hear about the second genome sequence made for a Denisovan. Denisovans are those enigmatic early human relatives of ours. We're going to find out what the new genome tells us about our relationship to them and the interbreeding that went on between us and them.

0:46It's obvious that it's all so much more complicated. They're kind of exciting.

0:50Bill Bryson:Yes, also on the show this week, Formula E electric cars are on the verge of outperforming Formula 1 petrol cars. Formula E is saying that the next car, the Generation 5, will probably be as fast or faster than Formula 1. But it depends how long the race is. We're finding out what that means. And we're also going to be discussing new findings about Epstein-Barr virus. It causes a range of diseases. You may know it as mono, kissing disease, glandular fever. 95 % of us have it and we're still finding out what it's doing to us. I did not know that. All I knew was that if you have a cat, you're likely to have feline.

1:23Toxoplasmosis. That feline virus. I probably got that.

1:31Bill Bryson:Welcome to The World, The Universe and Us from New Scientist. I'm Dr Penny Sarchet. And I'm Dr Rowan Hooper. And we have a special guest with us this week, science writer, legend, Bill Bryson. And when I mentioned in the office that Bill was coming on the pod today, people reacted like, you know, Ryan Gosling was coming in or David Beckham or something. It's my looks, it's my looks. Bill's book, A Short History of Nearly Everything, was published in 2003. It sold like absolute billio. Best-selling non-fiction book of the 21st century. And he's now revised it. And we're going to talk about that later in the show.

2:07But we thought it would be great to have you on the podcast with us ahead of that. Welcome to PodBuild. Very honoured to be here. Thank you, Rowan.

2:14Bill Bryson:Let's talk about one of our favourite subjects, the human family tree. Well, it's a bush, isn't it? A shrub. A hedge. A kind of hedge row. The story this week is that for only the second time, researchers have obtained the full genome of a Denisovan, and that's a group of ancient humans who lived in Asia. And the DNA from this one was extracted from a single molar, a 200 ,000-year-old tooth found in this cave in Siberia. Yeah, and you may be thinking, well, how interesting is that really? David Reich at Harvard described this as a bombshell paper. Why is that? Well, so these Denisovans, they came out of nowhere.

2:52I checked the first edition. They're not in it because they weren't discovered back then.

2:57Bill Bryson:15 years, isn't it? We've got 15 years of knowing that they existed at all, even though they're a really close human ancestor. Yeah. So they were the first ancient human to be discovered by DNA alone. And I just read in your new book, Bill, the origin story of the name Denisovans. Oh, yes. It was from a cave in Siberia that was said to have been inhabited by a saint named Saint Denis. I did not know that. A hermit. A hermit, yeah. Fantastic. Well, it reminded me of the hermit in life of Brian, you know, in that cave. He was living there. And then, you know, hundreds of thousands of years later, he's got a species named Arthur.

3:38Bill Bryson:Well, not quite a species, but that's a whole thing. We might get to that. Yeah. So the story of the discovery is that Svanti Pabo, he basically invented paleogenetics. He was sequencing DNA from Neanderthals and he was sent this fragment of bone from this cave. He expected it to be a Neanderthal and he found something completely different. Yeah, and we've talked about Denisovans a lot on the pod before. For a really long time, all we had were those fragments of bone and the DNA sequence. And there's been a flurry of findings recently, especially this year. So what's the new bombshell finding now?

4:10Bombshell is that this new genome reveals that there are at least three separate populations of Denisovans with completely different histories. So it shows that the early Denisovans interbred with an unidentified group of ancient humans and with a previously unknown population of Neanderthals.

4:30Bill Bryson:So there's a whole other ancestral group out there that we didn't know about before. Yeah. So the ancestral branch that led to Neanderthals and Denisovans, they left Africa well over 400 ,000 years ago. Our ancestors then sort of carried on evolving in Africa, became Homo sapiens, and then they left 50 ,000 to 60 ,000 years ago. But yes, since that first identification of Denisovan in 2010, we found a few more samples from, but all from around Asia, East Asia. Because we recently reported on a skull found in China that has now been ID'd as a Denisovan. It's the first time we've actually known what their faces look like.

5:13Or their skulls. Well, you can infer that, right? Yeah, you can. So we've only got these fragments of DNA, despite the fact that we've got these other bits and bobs, the skull and other fragments of bone. We've only managed to get fragments of DNA, not enough to make a whole genome. but they've been going back to that Denisovac cave over and over and in 2020 they found this molar there and as we know teeth are a great place to get DNA from and that's what they've managed to do now

5:44Bill Bryson:And so was this tooth yielding the same genome that they were studying back in 2010 or has it given us an entirely new genome to look at? Yeah, so that's the interesting thing based on the number of mutations in the new genome and comparisons to other ancient humans, the team now have estimated that this individual lived about 205 ,000 years ago, so really long ago, and supporting that, the sediments where the tooth was found were about 170 ,000 to 200 ,000 years old. But the other high-quality genome that we already had was from a Denisovan who lived only 55 ,000 to 75 ,000 years ago. So in other words, the genome we've just got from the tooth is from a much earlier stage of Denisovan history.

6:29Bill Bryson:So amazing to think that it goes back that far. And also that all the way throughout that time, they were using this cave on and off. Yeah, what a historical site for humanity, really, in the broadest sense. And based on comparisons with the other remains, the team say that there are at least these three discrete Denisovan populations. So in the cave alone, you find these two. the oldest group that's where the male this new genome comes from the second group then replaced that population thousands of years later and so what's the third group? third group is not from the cave but from other remains and they're the ones that interbred with us not me personally you're not that old are you?

7:13Bill Bryson:yes because we do know that we carry Denisovan DNA and some people carry as much as 6 % I think so there clearly was interbreeding but does that mean we haven't actually yet found a genome of this third population that we interbred with we we still don't really know much about them no that's right um we know there was interbreeding from other denisovan dna from elsewhere but we don't know about them genetically really because we haven't got their genome yet right so there's there's still loads to discover here and unpick about the denisovans and their intertwined history with us i mean it's like a soap opera isn't it going on over hundreds of thousands of years here with all this stuff that's going on.

7:52So the new genome also reveals that this thing about the interbreeding with Neanderthals, the Denisovans and the Neanderthals, who also lived around this Denisova cave. The genome had traces from a Neanderthal population that we know lived 7 ,000 years or so before this Denisovan who lost his tooth there. And these traces don't match any known Neanderthal genome though. So the suggestion then is that the Denisovans interbred with a Neanderthal group that has never been found. So this is another sort of part of the jigsaw that there's a missing gap there. The Denisophans also seem to have interbred with an unidentified group of ancient hominins that evolved independently of Denisophans and modern humans for hundreds of thousands of years.

8:41Bill Bryson:So it really is looking like a shrub. Like you say, there's all of these different populations of different types of human, including Homo sapiens and our closest relatives. and we're discovering these genetic hints all the time that there were these other groups, not just in Africa, all over the place. And there's still so much more to sort of understand what was exactly going on at this point. Yeah. Bill, has this surprised you over, you know, when you wrote the first edition of your book? Was it starting to look quite straightforward? Yeah, it was. It actually, it was. I think, I mean, not just to me, but I think to people in the field were pretty confident that they had kind of figured things out.

9:18And then all this new stuff, not just the Denisovans but also the Homo floresiensis and just various other archaic human groups that have been found since that were never suspected. And it's obvious that it's all so much more complicated but kind of exciting too. And the thing that fascinated me as a complete outsider to all this is how did these people all get around? I mean, how did they disperse? And what happened when they came upon each other? You know, there must have been – I think there's a tendency to think that it would lead to some sort of tension, fighting. But actually, it ended up with – Interbreeding.

9:58Interbreeding. Quite a lot of introgression, as they say. Yeah, yeah. And, yeah, I think that's amazing. I think it's kind of heartwarming, too, the idea that these people were living side by side and together for long, long, long periods. because modern Homo sapiens don't do that very well at all. No. I mean, obviously the tragedy is they all went extinct apart from us. Yeah. But I guess one nice thing is that we do find these remnant bits of their genome in us still, so they live on in some kind of way.

10:28Bill Bryson:I'm sure I've mentioned this before, but there's cool genes we have from the Denise Burns, and some of them lived up on these high Tibetan plateaus, and some people have genes from them that make it easier to breathe oxygen. at those altitudes. So it's amazing the sort of genetic footprint or, well, fingerprint that they've left in some of us. The reach they have still. Yes, absolutely. This message is sponsored by DEEP. This week, New Scientist CoLab explores Vanguard, a next-generation underwater habitat designed to allow humans to live on the ocean floor. Built to withstand the pressures of the sea and even the force of a Category 5 hurricane, it represents a major leap forward in engineering and marine science.

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11:44Bill Bryson:OK, let's talk about the Epstein-Barr virus. Did you know, Rowan, that most of us have a dormant virus that can cause autoimmune diseases within us? I did not know that. All I knew was that if you have a cat, you're likely to have that feline virus I probably got that. And I know that the human genome is riddled with bacterial DNA. Yeah. And I guess our microbiome is full of viruses. But I didn't know about this thing about the Epstein-Barr virus at all. Yeah. Even if you don't think you've ever had glandular fever or monomononucleosis, kissing disease, all of the different names for it. If you're an adult, it's almost certain that you do have it dormant in you.

12:23Bill Bryson:It's the Epstein-Barr virus and it's thought to infect 90 to 95 percent of adults globally. Wow. Yeah, it's huge. And once it's in your body, it's in you for life. Wow. So that makes it a really successful organism, if we're calling viruses organism. Well, really successful. So the story this week is that there's further evidence of why dormant viruses such as these are not just sort of secretly, you know, they can be a long term health problem. Yeah, because you'd like to think if we're going to have to live with these things, they're not doing anything, but that they may not be as dormant as they appear.

12:57Bill Bryson:And the discovery this week is that epstein-barr can cause changes in the immune system that can contribute to lupus an autoimmune condition um that involves the immune system attacking your body's tissues causes things like rashes joint pain hair loss fatigue yeah i mean i have to say lupus made me think of werewolves but it's because apparently it's because the the rash it causes it looks a bit like the bite of a wolf right so it's called lupus okay of course cancer yeah is caused is called that because people thought it looked like the skin cancer looked like the clip of a crab when you got bit.

13:31That's beside the point. That is beside the point. But what is not beside the point is, well, what's the, how concerned should we be? Like 95 % of us might have this virus, but it only causes problems in, you know, 0.1 % of people.

13:45Bill Bryson:A fraction. Yeah, exactly. So even though almost all of us have this virus, it causes disease in very few people. But there are two reasons that I still think this is really interesting. So first off, this isn't the first time that Epstein-Barr really common virus has been linked to an autoimmune condition. I've been keeping an eye for a while on its strong links to multiple sclerosis. So that's kind of interesting there that this virus seems to be linked to two types of autoimmune disorder. So we're starting to get a picture now that it does mess with your immune system and cause these nasty conditions.

14:18Bill Bryson:And I'm always interested in autoimmune ones because they're horrible conditions. They affect women more often and we still don't understand them or treat them that well. But then on an even broader level, we do have, you know, this isn't the only virus we have dormant within us. There are loads of them. If you ever had a cold sore, you've got one of those. A lot of us who weren't vaccinated with chickenpox as kids, we've got that one lying dormant in us. HPV is a famous one. And increasingly, we're learning that they're involved in, you know, that you don't have them get over the acute infection and then you're fine for life.

14:51Bill Bryson:They can cause problems later on. And that's why we now vaccinate against HPV to prevent the cancers that it causes. And Epstein-Barr, we've known about it for about 61 years, but we're still learning quite a lot about it. So we first discovered it, or one of the first things we knew about it is it's linked to cancer too. But it also might be implicated in things like post-viral conditions, chronic fatigue syndrome, ME and the like. So it's really important that we understand what these dormant, supposedly dormant viruses are actually doing in our bodies. Yeah, yeah. So I had really, I have to say, hardly any idea about any of this.

15:23So that's really intriguing. And about lupus. So how do we know how it might shift over into causing this disease?

15:33Bill Bryson:So this is the new finding this week. The virus infects a type of immune cell called memory B cells. And these are really clever. What they do is they, when you've been attacked by something, they remember it. So if you then encounter that pathogen again, you can respond to it much quicker, much stronger and stamp it out. And so the new study looked at what the virus does in these cells. And they found that it triggers the expressions of genes that kind of recruit other immune cells and kind of ramp up this nasty cascade where all of these immune cells start attacking your own body rather than finding a repeat pathogen.

16:07OK, and that's what causes lupus. And does that mean we can interfere with that cascade and cure it?

16:13Bill Bryson:You'd hope so. But lupus, unfortunately, is a very varied condition. So it's thought that there's probably multiple mechanisms involved. However, this particular pathway might be the main causative pathway in some patients, but it's still early days, so we don't know. But you'd think any unpicking of this is going to be useful, hopefully, for treatments. yeah so you can imagine how there are so many different factors that tip you down a path into developing one of these things and there's multiple sclerosis too yes and do we know any other of these reasons why yeah you know you might get tipped into a pathway yes exactly if 95 of us have this virus why does such a small number stress or something oh yeah so environment is we don't know that much about yet but environment is very complicated and it's probably involved but genetics really is probably a large part of the factor um to predispose you or otherwise to autoimmune disorders um and then also as i mentioned women are more likely to have autoimmune conditions that's probably due to the fact that women have stronger immune systems um and and that seems to be we're gradually sort of unpicking this and we've got a great feature recently a new scientist on this about it's to do with how many copies of the x chromosome you have and the role that that chromosome plays in immunity.

17:31Bill Bryson:So that must be playing some kind of role in this as well. Wow. So what about vaccination? Are people thinking about this, vaccinating again? Well, I am, right? If we have one of these viruses sitting in us and we're gradually discovering that they can cause all kinds of issues later night. Well, they might do a lot of good, though. Can you name a virus that does us good? Not offhand. Okay, listeners, right in. but yeah i mean i guess we don't know part of our virome hollow biome yeah yeah the virome you know i wouldn't want to get rid of them all that's interesting yeah interesting um i mean yeah because that's where my mind went is okay we know this virus does a thing can we not just vaccinate it against it there has been preliminary work on that we don't have a vaccine at the moment some of the really interesting work has looked at um using specific vaccination against epitome bar to treat the cancers that it causes.

18:27Bill Bryson:So maybe you wouldn't vaccinate the entire population, but if someone has a cancer that's being driven by that virus... I'd be happy to be vaccinated for that one. Yeah, fine. But ultimately, it's all about working out the costs and benefits, right? And I'd be surprised if Epstein-Barr is doing something good for us, but I guess you can't rule this out, and that's why they do this kind of research, right? But I do think, you know, what? We've known about this virus for 61 years. There's still so much we don't know about it. But increasingly, there is this trend of realising that we have these things dormant in us that are actually potentially causing harm.

19:00Bill Bryson:And it's great to start shedding some light on what they're actually doing. Now, we talk about electric vehicles from time to time on the pod, mostly in the context of like loads are being sold in China. We're going to get rid of combustion vehicles. Hooray. And get rid of fossil fuels. This week, we have an electric car story that's a bit different. Environment reporter Alec Loon is here. Alec, your story is about Formula E electric race cars and how they could soon outperform Formula One regular fossil fuel cars. So what's the story? Well, yeah, that's absolutely right. They're getting very close to Formula One.

19:42Formula E, which started a little over a decade ago as a way to kind of showcase EV technology. In the first four years, they had to actually swap out the car in the middle of the race because the battery didn't last long enough to finish the race, right? So, you know, nobody was really looking at it as, you know, top class racing then. Okay, jump forward to today, and you have the Generation 4 Formula E car has just come out, and it has 815 horsepower. So that's almost as much as a Formula One, which is about 1 ,000 horsepower. and it can reach speeds of 220 miles per hour, which is almost as fast as Formula One at about 235 miles per hour.

20:25So it's within touching distance of Formula One. And Formula E is saying that the next car, the Generation 5, will probably be as fast or faster than Formula One. So it kind of raises this interesting hypothetical. if you put these two cars on a track together, could the electric car beat the Formula One, which for 50 years, Formula One has been the fastest road vehicle going around a track. And the answer is probably very soon it will be able to beat the Formula One. But there's a big caveat because it depends how long the race is. So anyway, the big advantage of electric vehicles is they're very efficient at converting energy into motion.

21:14You look at a combustion engine, it's only about 25 % conversion rate. So the majority of the energy is actually just being lost to the atmosphere as heat. You run a combustion vehicle for a while, the engine gets very hot, right? Well, that doesn't happen in an electric vehicle. Well, so do electric vehicles not heat up? The battery heats up. Okay, but the engine. The engine's pretty cool because it converts 90%.

21:41Bill Bryson:90 % compared to 25%. Compared to 25%. So up to 90 % of the energy that's going into the engine is converted into pushing the car forward. And the Formula E teams have gotten that up to 96%. And actually, it is so efficient that Formula One has taken notice. and Formula One has put batteries into their petrol cars to help with acceleration and to help with that energy conversion and Formula One's able to get now 50 % energy conversion with the help of batteries. Yeah, because the acceleration in an electric vehicle is their big thing, isn't it? It is nuts. So F1 cars are now using that at the beginning when they start off.