NATURE PODCAST

A powerful radio burst from a magnetic star

Astronomers pin down the likely origins of mysterious fast radio bursts, and the latest on what the US election means for science.

Hear the latest science news, brought to you by Benjamin Thompson and Shamini Bundell.

In this episode:

00:46 The origins of mysterious fast radio bursts

The detection of a brief but enormously-powerful radio burst originating from within the Milky Way could help researchers answer one of astronomy’s biggest mysteries.

Research article: Bochenek et al.; News: Astronomers spot first fast radio burst in the Milky Way

07:59 Coronapod

At the start of the pandemic, there were fears that schools could become hotspots for infections. We discuss the evidence suggesting that this is unlikely to be the case, and the rates of infection in children of different ages.

News: Why schools probably aren’t COVID hotspots

18:34 Research Highlights

Octopuses taste with touch, and a tool to watch dangerously-reactive metals grow.

Research Highlight: How octopuses taste with their arms — all eight of them; Research Highlight: How to make violently reactive metals and watch them grow

21:28 An update on the US election

Although the winner of this year’s US election is unclear, we discuss the current situation and what it might mean for science.

News: Scientists aghast as hopes for landslide Biden election victory vanish

28:58 Briefing Chat

We discuss some highlights from the Nature Briefing. This time, ancient genomes reveal the migration of man’s best friend, and a new polio vaccine looks set to receive emergency approval.

News: Ancient dog DNA reveals 11,000 years of canine evolution; News: New polio vaccine poised to get emergency WHO approval

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Transcript

Hear the latest science news, brought to you by Benjamin Thompson and Shamini Bundell.

Host: Benjamin Thompson

Welcome back to the Nature Podcast. This week, the stellar origins of a powerful cosmic radio burst…

Host: Shamini Bundell

And an update on the US election and what it might mean for science. I'm Shamini Bundell.

Host: Benjamin Thompson

And I’m Benjamin Thompson.

[Jingle]

Host: Benjamin Thompson

On 28 April this year, a powerful burst of radio waves lasting only a millisecond was detected here on Earth. This event, known as a fast radio burst or FRB, is one of the strangest phenomena we've observed in the Universe. FRBs have been known about for over a decade, but scientists haven't been able to explain what causes them until now. This week in Nature, three separate papers describe the first FRB that's been found within our own Galaxy, the Milky Way. Detecting an FRB so close to us has finally allowed researchers to pin down a source. Reporter Anand Jagatia spoke to one of the scientists who spotted the striking signal, graduate student Chris Bochenek from the California Institute of Technology in the US, who explained the long-standing mystery of FRBs.

Interviewee: Chris Bochenek

The first fast radio burst discovered output about as much energy in five milliseconds as the Sun outputs in about a day. All of them until this most recent burst have come from faraway galaxies. And because we can detect them from distant galaxies, that means that whatever is producing it, it must be extremely energetic.

Interviewee: Anand Jagatia

So, these fast radio bursts have puzzled scientists for quite a long time. What are some of the theories out there for what could produce them?

Interviewee: Chris Bochenek

For a long period of time, there were more fast radio burst theories, then there were fast radio bursts. But some of them include blitzars, which is what happens when a neutron star that is too massive to support itself collapses into a black hole. Merging neutron stars could produce fast radio bursts. But I think for a long time, the most popular theory has been magnetars, which are neutron stars which weigh a little bit more than the Sun but are comparable in size to Manhattan. What separates out magnetars from other neutron stars is their incredibly strong magnetic fields.

Interviewee: Anand Jagatia

Okay, how strong exactly is incredibly strong?

Interviewee: Chris Bochenek

So, a magnetar has magnetic fields 100 to 1,000 times as strong as a typical neutron star. And these magnetic fields are so strong that the structure of atoms themselves changes. So, you might think of like an electron cloud around an atomic nucleus as being somewhat spherical. But around a neutron star, the magnetic fields are so strong that this picture of an atom turns into more of like a pencil shape.

Interviewee: Anand Jagatia

So, powerful enough to squash the shape of atoms. Why has it been so hard to pin down fast radio bursts to magnetars if that's the most popular idea for their source?

Interviewee: Chris Bochenek

Because we've been seeing them from so far away. Even if you see fast radio bursts and other galaxies, you're not going to be able to pinpoint it to a specific star. So, the really great thing about this fast radio burst is that it happened so close by that we got to look at it right in the face. And so, this is the first time a fast radio burst has been identified as coming from a specific source.

Interviewee: Anand Jagatia

And that source, as you report in the paper, is a magnetar. So, how do you know that the fast radio bursts actually came from one?

Interviewee: Chris Bochenek

Yeah, so there are a couple ways that we know that this fast radio burst came from the magnetar. One is that this radio burst happened at the same time from the same relative sky location as an X-ray burst. So, we believe that the radio burst and the X-ray burst are related. The X-ray detectors can put the burst within about five arcminutes of the known position of this magnetar, which is pretty close.

Interviewee: Anand Jagatia

Right okay, and this fast radio burst was detected by, among others, a telescope that you were involved in building called STARE2. Can you tell us a bit more about how it works?

Interviewee: Chris Bochenek

Yeah, so STARE2 is a network of three fairly bare-bones radio antennas. What we use to actually detect the radio waves is basically just a six-inch pipe with two cake pans attached around it. STARE2 is a bit of an interesting radio telescope in that we made a very specific choice in its design. We knew that a fast radio burst in the Milky Way would be incredibly bright, so we don't need a very sensitive detector. But we also knew that a fast radio burst in the Milky Way would be a rare event, so we've got to be looking at the right place at the right time. So, we sacrificed orders of magnitude in sensitivity in order to be able to look at most of the sky at any given time.

Interviewee: Anand Jagatia

So, what was it actually like then when you opened the data and you saw there was a fast radio burst there? How did you react?

Interviewee: Chris Bochenek

I can't say we ever really expected that we would find a fast radio burst in the Milky Way. It just seemed like a bit of a wild idea. So, when I looked at my data to see the burst for the first time, I was actually like paralysed, like I couldn't do anything, like I just sat there for a couple minutes thinking like, is this it?

Interviewee: Anand Jagatia

What does this observation actually mean, and does it mean that we now know for sure what causes fast radio bursts? I mean, do all of them come from magnetars?

Interviewee: Chris Bochenek

I think that it's safe to say that some fast radio bursts come from magnetars. One outstanding puzzle is that some fast radio bursts are known to repeat and others are not, and we don't really know why, although magnetars are one of the more popular theories for repeating fast radio bursts as well.

Interviewee: Anand Jagatia

So, what's next now in the field? This is the first time a fast radio burst has been observed kind of directly within our Galaxy. What else do people want to know about them and about where they come from?

Interviewee: Chris Bochenek

I think one of the most important experiments that people are doing with fast radio bursts is trying to detect them with instruments that are capable of determining where exactly within a galaxy they came from so we can do detailed studies of those environments. I also want to do surveys of some nearby more star-forming galaxies that probably do have a lot of fast radio bursts because they have more young stars, which means they probably have more magnetars, which means you might not have to wait as long as we did for a detection.

Host: Shamini Bundell

That was Chris Bochenek talking with Anand Jagatia. To read Chris' paper, look for a link in the show notes.

Host: Benjamin Thompson

Time now for Coronapod, the part of the show where we discuss the latest coronavirus research. With me, as ever, is Noah Baker, and this week making her Coronapod debut is Nicky Phillips, who joins us on the line from Sydney, Australia. Hello to you both.

Nicky Phillips

Hello.

Noah Baker

Hi there, Ben. Hi, Nicky.

Host: Benjamin Thompson

Nicky, listeners might not recognise your voice. You've been on the show before, but for people who don't know who you are, what do you do here at Nature?

Nicky Phillips

Well, my job here for Nature is as the Asia-Pacific Bureau Chief, so my job is to commission and edit news stories from this great part of the world.

Host: Benjamin Thompson

Well, one of those new stories you've edited is about schools. Now, here in England, we're about to start our next nationwide lockdown, but one thing that's different to the last lockdown is that nurseries and schools are staying open, the government has said, much to the relief of many parents who might be listening to this show right now. But keeping educational settings open has been a little bit contentious in terms of virus spread. Nicky, maybe could just outline some of the reasons why that is?

Nicky Phillips

Yeah, well, I think at the beginning of the pandemic, there was a real fear that having children at schools in sort of confined spaces. If anyone knows kids, we know that they don't really socially distance and they've often got colds, passing on their germs to each other, so I think at the beginning of the pandemic, there was this big concern that maybe schools would become a place where outbreaks would happen. So, of course, scientists have been looking into this for months and months and I guess earlier in the pandemic, evidence was coming out that in countries or places where there wasn't very high community spread, it was quite safe for schools to be open. And so, we saw this in a lot of Asian countries, particularly places like South Korea and Japan and even a bit in Australia as well where I am, but then the big open question was what happens when the Northern Hemisphere goes back to school after their lockdowns and their big summer holidays? So, I think people were really anxious to see what would happen in schools in the US and in Europe where there was higher community transmission of the virus. So, only just recently are we starting to see the evidence of the big studies done in schools.

Noah Baker

So, yeah, I think there's been concern on a few fronts here about schools. So, one is that there's the risk to children and of course staff that are in schools of becoming infected, and essentially turning schools into these sort of super-spreader events. But the other risk is that schools could act as a sort of a vector. So, kids, although they're not necessarily getting sick with the virus, even if they're getting infected, they could be taking it back home again and then spreading it within the community. And so, these are two things that people really want to keep track of, and now these big studies, as you say, are starting to come out and they're seeming to suggest that schools don't seem to be the potential sort of super-spreading centres that people have been concerned that they might be, and as to why, well, that's kind of an open question as it stands.

Nicky Phillips

Yeah, exactly. I mean, now that we have had these big studies done in schools across countries or states, particularly in places like Italy, in the state of Victoria in Australia, we've sort of been able to get a sense of whether or not schools are hotspots. And it seems at the moment, they're really not. Of course, there are outbreaks in schools – there are going to be outbreaks anywhere – and what the evidence seems to suggest is they're usually pretty small when they do happen. I think there was a study in Italy that found a high proportion of outbreaks in the country, when they did happen, they were only in one or two people, and very few got up to the number of ten people in a school being infected. So, they weren't these sort of super-spreading events. And actually, even in the US where transmission rates are pretty high in a lot of regions, we're not really seeing that infections in schools are spilling over into the community and driving transmission even higher.

Host: Benjamin Thompson

I mean, we've talked about sort of schools with quite a broad brush there, Nicky, but of course, kids could be 4 years old or they could be 16 years old. Are we seeing any differences in the patterns there or is it across the board relatively good news?

Nicky Phillips

Yeah, that's a really good point. There is some nuance in this data. It seems that children who are under the age of about 12 are less likely to get the virus and are less likely to pass it on to other people, and that includes other children and other adults. Whereas children who are between the ages of about 12 to 14 and 18, there are higher numbers of kids getting the virus. And so, that's important when it comes to schools, because if you are in high school, then maybe extra precautions need to be taken for high schools rather than kids who are in younger grades because that seems to be where the transmission difference is. There's a bit of a gradient over ages and I think teenagers in their late teens transmit the virus similarly to adults.

Noah Baker

It's a really interesting one, right? Because this is another question that has arisen which has pointed to the holes in the scientific community's knowledge. So, there are certain things that we just don't really understand, and one of the things that it's a struggle to understand is how diseases like this transmit in children because quite often, lots of steps are taken to protect people in those environments. And certainly right now, kids have gone back to school. My mum works in a school and I can tell you the levels of protection that are being put in place are quite extreme. And so, there is lots of encouraging of kids not to mix, kids are staying in cohort groups so they don't interact with anyone outside of that cohort, everyone's wearing masks and so on. And so, it's really hard to get a sense of how these transmission dynamics work when there are all of these procedures in place to try to reduce spread, which is sort of tainting the data, I suppose.

Nicky Phillips

Yeah, kids aren't in a natural environment in schools at the moment, so when the data says that it looks like children under the age of 14 aren't getting the virus as much as adults, is that partly because we're just keeping kids away from each other? So, yeah, it's definitely an open question. I mean, if it is the case that children are less susceptible at getting the virus, scientists have some theories about why that might be the case. Maybe it's this idea that they're smaller, they have smaller lungs, so they're less likely to cough out, for want of a better word, a big bunch of SARS-CoV-2 viral particles that are going to spread through the air and infect someone. If you think about a classroom environment, it's often a teacher at the front talking whereas the kids are supposed to be listening. So, there might be environmental factors at play, there might be physical factors, so while there is this data suggesting that schools aren't hotspots, there's a lot we don't know about what's going on in the dynamics of children and schools and how the virus is being spread.

Noah Baker

And it's also worth mentioning another kind of perennial problem that all attempts to understand the sort of dynamics of spread are also a little bit hindered if you have a testing policy which means you only test people when they show symptoms. If people are asymptomatic and they're not testing then you're missing quite a significant chunk of the viral transmission, which really muddies the picture. And there is evidence to suggest that about 50% of young children are asymptomatic when they get infected, which could be a huge impact in a school context.

Nicky Phillips

Absolutely. Until we test everyone in a certain environment, we’re never going to get a true picture of what's going on. And it is true that there is evidence or kind of growing data that children are more likely to be asymptomatic. I mean, one of the perennial issues about asymptomatic cases is are they definitely asymptomatic or are they just pre-symptomatic or they just have such mild symptoms that you wouldn't even classify it as something? I mean, how many kids have a runny nose? Are you going to automatically think it could be COVID? So, yeah, lots of knotty issues in the whole thing.

Host: Benjamin Thompson

I said at the top then that this was kind of a contentious issue between different groups about whether schools should be open or not, and I think we've seen two sides of a debate here then that it seems that these aren't super-spreading events but also that there may be more underlying levels of the virus than we know without better testing. So, the debate presumably is going to continue, do you think?

Nicky Phillips

I think at the moment, there is good evidence that if there is low transmission in the community then it is safe to open schools and to keep them open, and I also think there's probably good evidence that when there's moderate transmission, as long as the school takes good precautions in terms of social distancing and hygiene and all sorts of things, then they're not going to be super-spreading events. But I guess we don't really know what would happen in a school if the community transmission is really high and the school doesn't take any precautions. I mean, in that sort of scenario, in any case, that's probably not going to end well and schools would be no different. But yeah, I agree with you. I think there's a lot we don't know about what's going on, so I'm sure we'll be talking about this for a while yet.

Noah Baker

And in the meantime, I think there is evidence to suggest that the risk to people grows with age and so maybe the teachers at the schools are going to be the ones that are wanting to take the most precautions, or maybe the older cohorts, the 17, the 18 year olds, because that's when the risk seems to go up as far as the data is concerned.

Nicky Phillips

I mean, you really do feel bad for teachers in this situation because while it does look like schools aren't a high-risk place, if you're in a vulnerable group, then you kind of want to lower your risk of getting the virus as much as you can. So, yeah, I think it's a difficult one.

Host: Benjamin Thompson

Well, Nicky, I hope you'll join us again when more data does become present and we can maybe keep discussing this issue, but for the time being, Nicky and Noah, thank you so much for joining me.

Nicky Phillips

Thanks so much for having me, guys.

Noah Baker

Thanks, Ben.

Host: Benjamin Thompson

More from Coronapod next time. Coming up later in this week's show, we'll be joined by Lauren Wolf, Nature's Americas Bureau Chief, to get the very latest on where things stand in terms of yesterday's US election and to hear all the reactions from the world of science.

Host: Shamini Bundell

And sticking with science and politics for just a second, don't forget to have a listen to our brand new three-part series, Stick to the science, where reporter Nick Howe tries to get to the heart of what science’s relationship with politics actually is and what it should be. Head over to the show notes where you'll find links to that and to a survey where you can give us some feedback on the series. Now, though, Noah’s back with this week's Research Highlights.

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Noah Baker

Octopuses can use their arms to taste their prey. Now, researchers have worked out how. Those that study octopuses have known for years that the suckers on their arms contain cells with a myriad of sensory talents, including touch and, indeed, taste. But now, they’ve found proteins on the surface of some of these sensory cells which help explain how they work. The tiny detector proteins respond to contact with specific molecules, including terpenoids, which many marine invertebrates produce as a defence mechanism. After binding to the chemicals, the receptors generate an electrical signal that passes chemical and tactile information to the octopus nervous system. The findings could explain how octopuses explore the sea-floor, attacking prey like crabs but ignoring inanimate objects, by tasting their way with their arms. Read more in Cell.

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Noah Baker

Researchers have found a new way to make violently reactive metals and watch them grow at the same time. You may remember from high school science class just how reactive the metals lithium and sodium are in their pure elemental form, and that makes them difficult to study. But now, researchers have used a clever trick to watch them forming, by repurposing a relatively standard bit of kit – a transmission electron microscope. Transmission electron microscopes (TEMs) create images by shining a beam of electrons through a target material. The team used this to bombard compounds that contained either lithium or sodium with electrons. In response to the barrage, the compounds decomposed. As they broke down, crystals of pure lithium or sodium precipitated and rapidly extended outwards and because they're in a TEM, scientists could watch the process happen. The crystals grew to a couple of hundred nanometres around within seconds, before the crystallisation slowed. Even though the samples were in a vacuum chamber, the researchers determined that trace amounts of oxygen managed to oxidise the surface of the metals. They also saw long crystalline fingers extending from the lithium crystals, which they suspect also develop gradually inside lithium-ion batteries, shortening battery life or even causing fire. The author's hope that their TEM technique could help decipher the fingers’ mysteries. Read more over at Nature Communications.

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Interviewer: Benjamin Thompson

Next up, the big story this week is, of course, the US election, and I'm joined on the line from Washington DC by Lauren Wolf, Nature's Americas Bureau Chief, to talk about it. But, Lauren, before we start, it must have been a pretty long night for you. How are you feeling right now and have you had any sleep?

Interviewee: Lauren Wolf

Have I had sleep? I had some sleep, I think. At Nature, of course, we were following the election hoping to put up some sort of story in the wee hours of the morning. But it became increasingly clear as it approached midnight here on the East Coast that there was no easy answer to what story exactly we would be putting up. So, we continued to monitor the situation and we all just took a few hours of shuteye and are now back at it working on some reaction from the community.

Interviewer: Benjamin Thompson

Well, it's important to note that this is very much a developing story, and we're recording this just a couple of hours before the podcast goes live. There's still a lot of results to come in and it seems like there's no definitive winner just yet. What's the abridged version of where things are right now?

Interviewee: Lauren Wolf

Well, the election was not the landslide that some people thought it might be or that scientists hoped that it might be. Many people thought that Biden was going to win pretty decisively, based on the polling that had been going on for weeks before the election. Now, that doesn't mean that Biden couldn't still win, but things are a lot more in a deadlock than everyone thought it was going to be.

Interviewer: Benjamin Thompson

Well, Lauren, you were on the show a few weeks ago talking about what this election might mean for science and the scientific community. Now, plenty of things are still very much up in the air as we speak. Is there any updates on that at all?

Interviewee: Lauren Wolf

I think we're all just waiting to see what happens. I think the stakes are just as high as they were. A lot of scientists were really hoping that this election was going to go to Biden. They've been very upset about the damage Trump has done to scientific integrity in the United States, the way that he has ignored advice from health experts, particularly during the pandemic, the fact that we've had so many people die. And we've spoken to some scientists and some political scientists and some historians about what they think of this nail-biter election that we've got going on right now. Some of the scientists have said it's depressing to see that the American electorate has not sent a strong message and had this more decisive victory, repudiating everything that Trump has done, and they're worried. Other folks have said the fact that this isn't a landslide victory for Biden is a statement about scientists not being able to properly get their message across to people in the United States about how Trump has caused damage. It seems like it's more of a statement about scientists being out of touch with the rest of the population. And also, I mean, more broadly, beyond science, the fact that the political divide in the United States is just as wide as ever, and doesn't seem like it's going to be getting any better anytime soon.

Interviewer: Benjamin Thompson

One of the key science issues that's still going on is, of course, the pandemic, and it was a big debating point on both sides before the election, but it also seems that COVID-19 may have some bearing on the result and how long it takes to find out what it is.

Interviewee: Lauren Wolf

Yeah, definitely. So, in the US, leading up to this election, a lot of people chose to do mail-in ballots. It's not that mail-in ballots haven't existed in the US in the past – in fact, they've been used since the Civil War – but this year more than ever, mail-in ballots are being used because of pandemic. People feel unsafe about going to polling centres in person and so they had their mail-in ballot option, and a lot of states actually expanded the ability for residents to do that. At the same time, mail-in ballots take longer to count and so that’s some of what we're seeing here with the election delay, and also at the same time, more Democrats are using mail-in ballots to vote. Trump made a number of statements in the lead up to the election about how mail-in ballots are fraudulent and kind of encouraged his supporters to vote in person. And so, what we're seeing is that that's going to become a sticking point. He's going to continue to question the mail-in ballots that are coming in late and claiming that they are fraudulent.

Host: Benjamin Thompson

Putting the presidential election to one side just for a moment if we can, of course, there's been some elections for the US Senate, as well. What are the science headlines there?

Interviewee: Lauren Wolf

The science headlines there, well, we still don’t have a complete answer about the Senate. All of the votes aren’t in, but what we do know is two scientists, Mark Kelly and John Hickenlooper, won seats. So, Hickenlooper is a geologist and Mark Kelly is a former astronaut. He's one of the twins, if you remember. His brother Scott was the one who went up onto the ISS, and they did sort of that twin study. And on top of the Senate elections, there are also some science-related propositions that were being voted on ballots in various states. In California, on the ballot there is a vote to refund something called the California Institute for Regenerative Medicine that does research on stem cell science and using those cells to be able to find cures for various diseases. And so, it had been created years ago and the funding has now run out, and so on the ballot currently is basically a proposal to refund this institute and keep it running. We're following that at the moment. It does look like it's going to be refunded. But it’s still too soon to say that definitively.

Host: Benjamin Thomspon

Well, stepping away from the actual results, Lauren, let's maybe go a little bit inside baseball. You're leading on Nature's US coverage, of course. How do you go about reporting on something that is so up in the air and, as you say, you stayed up all night trying to work out what was going on when. You must have had some terrifically large flow diagrams to work out what stories to write.

Interviewee: Lauren Wolf

That's a great question, and we are not the only outlet that I'm sure was doing this. I saw someone tweet last night that we should all have a moment of silence for all the paragraphs that are written and never used in the next few days because a lot of reporters, what they do is they kind of scenario plan, and we definitely did this. We were watching the news ahead of the election, we see what people are predicting is going to happen and we kind of have the ‘Biden wins’ plan and the ‘Trump wins’, and despite the fact that we are still working on our story, we did have the ‘no result’ plan, it just was not definitive at midnight last night that there wouldn't be a result in a few hours, so we didn't want to move forward with that until we were sure. And so, anyway, yes, we definitely plan these things out, have some experts on tap that were available until midnight last night for us to call and people that are available to us this morning, and that's basically how we're doing our work. And in terms of writing something about a ‘no result’ result, as I said, there's still a lot of reaction from the community. People are kind of upset that this wasn't a landslide. And so, we're gathering that reaction right now and putting it together to keep our readers up to date on what's going on and things that are relevant to them, and this is definitely one that everyone's watching.

Interviewer: Benjamin Thompson

Lauren, thank you so much for joining me today, and I'll let you get back to writing those stories.

Interviewee: Lauren Wolf

You are quite welcome.

Interviewer: Benjamin Thompson

Nature’s Lauren Wolf there. Keep an eye on nature.com/news for all the latest updates on the election.

Host: Shamini Bundell

Finally on this week's show, it's time for the Briefing chat, where we discuss a couple of articles that have been highlighted in the Nature Briefing. Ben, why don't you go first. What's caught your attention this week?

Host: Benjamin Thompson

Well, Shamini, I know you love an animal story, and I've got one this week all about dogs.

Host: Shamini Bundell

Ah, I do love animal stories but I mean, how much can there possibly be to discover about dogs? Presumably, you mean domestic dogs, not just sort of all canines?

Host: Benjamin Thompson

Yeah, that's right, I’m talking about domesticated dogs at this point, and this was a story that came out of Science, and it's looking at the migration of dogs throughout history with human populations.

Host: Shamini Bundell

And presumably dogs being sort of quite reliant on humans, there were sort of a lot of matching migration patterns as humans moved around the globe?

Host: Benjamin Thompson

In many cases, that's absolutely right, Shamini, yeah. So, the setup to this work is a lot of research into sort of dog populations has been done on modern dogs. But what a team of researchers have done now is they've gone back and really expanded out the number of ancient dog genomes that have been looked at, so from 100 years all the way up to 11,000 years old, and they've compared these to sort of contemporary human genomes to work out who went where, when, and what populations mixed and that sort of thing. And it turns out that about 11,000 years ago, there were five quite distinct lineages of dog that really have sort of percolated around the globe.

Host: Shamini Bundell

Cool, and where did these five lineages sort of come from?

Host: Benjamin Thompson

Well, the history of where they came from is still an unanswered question. Well, which wolf was domesticated and when is still a hotly debated thing. But if we've not got an idea of where they came from, I think we’ve got a better idea of where they went. So, in this new research, with access to the genomes, the researchers could follow these ancient canine populations as they moved and mixed, and sometimes their travels matched with the humans. For example, when Middle Eastern farmers expanded into Europe, they took their dogs with them, and the dogs, like their masters, mixed with the local populations and you can see how that went through time. But there's still some questions to be answered. For example, the influx of humans to the steppes of Russia and Ukraine about 5,000 years ago saw a change in the genetic makeup of the humans there but not the dogs. So, either they didn't take the dogs with them or they preferred the dogs that were already there. These are the sort of questions that remain to be answered just yet.

Host: Shamini Bundell

So, potentially looking into the genetics of humans’ best friend could give us a glimpse into our own history.

Host: Benjamin Thompson

Yeah, there's a quote in the Science article saying that if you see a bunch of dogs in a dog park, they may all have lineages dating back up to 11,000 years, which is kind of neat. But that's enough from me. Shamini, what have you got this week?

Host: Shamini Bundell

So, a bit more sort of a serious topic. I've been reading an article in Nature about the latest in the sort of battle against polio, which is obviously one of those big diseases that the World Health Organization has been trying really hard to eradicate.

Host: Benjamin Thompson

Yes, it's one of those sort of last holdouts, isn't it? I remember hearing Bill Gates give a talk a few years back and he said that the last 1% of eradication requires 99% of the effort.

Host: Shamini Bundell

Yeah, and the really frustrating thing is that the type of polio that is currently spreading in the Southern Hemisphere and in certain countries is actually a variant that has come from polio vaccinations that people have been given.

Host: Benjamin Thompson

Right, I mean, it's an oral vaccine and it’s an effective one, but it's not without its potential problems.

Host: Shamini Bundell

Yes, the oral vaccine is an attenuated version of the virus, and if that version of the virus is allowed to circulate in a population for a long time – for example, a population which has poor sanitation and low immunity to be able to fight this – then the attenuated version can mutate and turn back into a sort of more effective form of polio. So, what the World Health Organization want to do is come up with a new vaccine, a hopefully very safe vaccine, that will cover both this sort of new variant and the original wild polio. And this is particularly important during the pandemic because a lot of polio vaccination programmes have had to stop, so immunity is going down, so that’s sort of helping to cause this sort of resurgence. And that urgency means that the World Health Organization want to get a vaccine that’s sort of in the process – has been through phase one trials but hasn't yet been completely studied and licenced yet – and get that out there to people quite urgently through the WHO’s emergency listing process.

Host: Benjamin Thompson

Yeah, I mean, obviously, we talked a lot about vaccine development on Coronapod, and it's a multi-step process, but you're saying here that the WHO are hoping to speed the process along and get the vaccine to where it needs to be.

Host: Shamini Bundell

And this is also the first time that they've pushed something through like this. So, it is obviously quite interesting, as it could be the same process you could go through for a potential coronavirus vaccine.

Host: Benjamin Thompson

Well, thank you for that update, Shamini, and listeners, if you'd like to know more about both of these stories, you'll find links to them in the show notes. And if you'd like even more stories like this then sign up for the Nature Briefing and they'll be delivered directly to your inbox.

Host: Shamini Bundell

Before we go, there's just time to remind you once again to have a listen to our new podcast series about science and politics called Stick to the science, and you can find that wherever you get your shows. And as always, you can send us a message. We’re @NaturePodcast on Twitter or podcast@nature.com if you prefer email. I'm Shamini Bundell.

Host: Benjamin Thompson

And I’m Benjamin Thompson. Thanks for listening.

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