Mexican cavefish, the gut microbiome, and a wearable brain scanner

Interviewer: Benjamin Thompson

Hello and welcome to the Nature Podcast. This week, we’ll be finding out about the genetics of a blind fish, hearing about some new microbiome research…

Interviewer: Shamini Bundell

And we’ll be learning how to make a new brain-scanning helmet. This is the Nature Podcast for the 22^nd March 2018. I’m Shamini Bundell.

Interviewer: Benjamin Thompson

And I’m Benjamin Thompson.

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Interviewer: Benjamin Thompson

In our first story today, I’d like to talk about a strange little fish called Astyanax mexicanus, also known as the Mexican tetra. These fish are found in freshwater rivers and streams in eastern and central Mexico, and up into Texas, places like that. Not all of these fish live above ground though, and some isolated populations live in caves, beneath the limestone mountains in northeast Mexico. It’s a tricky place to live for a fish, as Nicolas Rohner explains.

Interviewee: Nicolas RohnerThe cave environment is entirely dark. There’s no lights or no plants, no photosynthesis, and therefore, at least to all knowledge, there is literally zero food in these caves.

Interviewer: Benjamin Thompson

Despite the lack of food, tetra populations survive. Although, they’ve undergone some fairly extreme changes, compared to their surface-dwelling relatives. These cave fish, as they’re known, have no eyes, and have developed lots of strategies to help them survive in the long periods between the seasonal floods that wash food into the caves.

Interviewee: Nicolas Rohner

What we found is that first of all, that most of the cavefish populations that we looked at have an increased appetite, so they would eat much more than surface fish if you give them the opportunity to eat as much as they want. And that helps them to gain incredible amounts of body fats, they have up to ten times more body fat. They store their fat everywhere, you find it in the eye socket, you find it in the brain. They have a lot of visceral fat, and while the surface fish, under a normal diet would not have these effects.

Interviewer: Benjamin Thompson

Another difference between the two groups, is that the cave fish have wildly fluctuating blood glucose levels, compared to the surface fish.

Interviewee: Nicolas Rohner

So, they basically have much higher blood sugar levels compared to the surface fish, after a meal and also after a day fast. And then, their blood glucose control is also altered because they’re not able to maintain this blood sugar level over a long period of fast. So, if you fast them longer, their blood sugar goes down, and they are not able to maintain their blood sugar. So, it seems like they have a generally dysregulated blood sugar homeostasis.

Interviewer: Benjamin Thompson

So, what’s going on? Generally speaking, blood sugar levels are regulated by the pancreas. After eating, when blood sugar levels are high, the pancreas releases the hormone insulin. Insulin binds with cells and leads to the uptake of the excess glucose, lowering blood sugar levels. In humans at least, a lot of this happens in the skeletal muscle. In this new work, Nicolas and his colleagues showed that for two cave fish populations with fluctuating blood sugar levels, insulin is being released. But, it’s impaired in its ability to bind to the skeletal muscle.

Interviewee: Nicolas Rohner

We found a mutation in the insulin receptor itself. Having this mutation leads to a decrease in binding of insulin, and it’s not as sensitive as the surface form or the un-mutated form. It’s not a complete loss of function, so there is still some signalling, but it’s basically decreased.

Interviewer: Benjamin Thompson

In humans, the inability of cells to respond to insulin, known as insulin resistance, is often a factor in metabolic diseases like type 2 diabetes. The mutation found in the cave fish is identical to one involved in a very severe type of diabetes in humans. However, the fish seem perfectly happy. They live to a similar age to the surface fish, and even appear to show fewer signs of age-related decline. So, if this mutation is giving these fish an advantage, why is it not more widespread?

Interviewee: Nicolas Rohner

We think it comes at a price. We already see this because we were able to mimic the same mutation in zebrafish, and while zebrafish, again, also they became bigger and faster compared to not having this mutation, they already had some other growth problems. So, for example, when we looked at their scales, they were smaller, so it somehow comes at a price. Therefore, we believe it may be important if it’s all about making it to the next step, where the food is very limited, like in a cave environment, but as a regular fish, if you don’t really have to, you don’t want to go that route. However, we believe because cave fish had that additional several thousand years maybe, even a hundred thousand years, of time to evolve with this mutation, they probably have found co-factors that help them to mitigate the otherwise negative problems that are associated with having this mutation.

Interviewer: Benjamin Thompson

In trying to understand how cave fish have adapted to survive in such an extreme environment, this single mutation is only a piece of the puzzle. The team showed that cave fish from another population still have high blood sugar after eating, but don’t have this altered insulin receptor. They too seem perfectly healthy, and the reasons behind all this are still unclear. However, the dysregulation of blood glucose seems to give all these cave fish an advantage. And there is some interesting conversion evolution at play, with different populations having achieved it by different methods. Quite how the cave fish are able to survive with a phenotype that could be very detrimental in humans, is yet to be understood. There’s still a lot to learn, says Sylvie Rétaux, who’s written a News & Views article to accompany the paper.

Interviewee: Sylvie Rétaux

It’s a great paper which asks more questions than it gives maybe responses, but it’s a great paper, that is unanticipated, unexpected, it doesn’t make any sense. But still it’s there, and it’s that.

Interviewer: Benjamin Thompson

It is of course tempting to think that this new finding in cave fish, will help us in our understanding of human disease. But Sylvie recommends caution.

Interviewee: Sylvie Rétaux

The translation thing into human health, I think it’s a really big step. And I think you really, it has to be considered that obviously, this insulin signalling pathway, is not working exactly the same way in fish and in mammals.

Interviewer: Benjamin Thompson

Nicolas though, is a bit more optimistic, and thinks that studying nature could give a fresh perspective on human diseases.

Interviewee: Nicolas Rohner

We always think of phenotypes of diseases as a terrible thing, but we often forget that many animals actually have evolved very similar phenotypes, that we see in human patients. Like for example, giraffes have high blood pressure as their normal situation, because they need to get the blood up to their head, and also these cave fish have high blood sugar, hibernating animals are insulin resistant, and so there is a lot of variation out there in nature that I think should be more studied if we want to understand also human diseases. And I think this is something that is not done a lot, and so I hope that at least this study will be informative for sure.

Interviewer: Benjamin Thompson

That was Nicolas Rohner from the Stowers Institute for Medical Research in the US. You also heard from Slyvie Rétaux from the Paris-Saclay Institute of Neuroscience in France. Both the paper, and the News and Views article can be found at nature.com/nature.

Interviewer: Shamini Bundell

Now, everyone knows it’s important to take care of your body. Here at the Nature Podcast, for example, some of us are making an effort to take the stairs instead of the lift every day.

Interviewer: Benjamin Thompson

We literally just took the lift down here about ten minutes ago.

Interviewer: Shamini Bundell

Well, yeah, okay I’m making an effort, I’m not necessarily doing very well at it. But anyway, it’s not just physical exercise that’s important. This week I’ve been hearing about our microbiomes, the communities of microbes that live on and in our bodies, and how they could play an important role in our health. Take commensal bacteria in our intestines, they help us digest food, they produce nutrients, they’re potentially important for our immune systems, and they seem to vary depending on lifestyle factors like food, exercise and health. In fact, some studies have observed that particular patterns of gut bacteria are associated with medical conditions. Take diabetes for example, which Ben was talking about earlier. For a while, it looked like people with type 2 diabetes had different microbiomes than people without, and researchers assumed that this was due to the condition itself. But it turned out there was a confounding factor, as Lisa Maier explains.

Interviewee: Lisa Maier

The very first example was the anti-diabetic drug Metformin. So, earlier studies actually reported that there is a gut microbiome signature shift for type 2 diabetic patients, but the signal turned out to be due to Metformin, which is the leading drug against type 2 diabetes, and not the disease itself.

Interviewer: Shamini Bundell

Lisa was interested in this result because it was somewhat unexpected. While drugs such as antibiotics are known to have a big impact on a person’s microbiome, Metformin is not an antibiotic. Its main effect was thought to be on the human liver, so you wouldn’t necessarily expect the drug to have an impact on commensal gut bacteria.

Interviewee: Lisa Maier

And, of course, this raised the question, whether this is only restricted to Metformin, or whether other non-antibiotic drugs would also have an impact on human gut commensals.

Interviewer: Shamini Bundell

Lisa and her colleagues began to study whether various drugs might have an impact on any of the many bacteria commonly found in human guts.

Interviewee: Lisa Maier

So, we wanted to test a lot of different drugs, and a lot of representative human gut commensals. So, what we did is, we did a direct screen, where we assessed the effects of 1,200 drugs on 40 human gut commensals, one to one, so we always assessed the effect of one drug on one commensal. The results actually were quite surprising. Of course, we found that a lot of antibiotics inhibit at least one strain from our selection, but what was more surprising actually was the human-targeted drugs. For them, we found that 24% inhibit at least one strain.

Interviewer: Shamini Bundell

Almost a quarter of the non-antibiotic drugs that they tested, that’s drugs that aren’t intended to target bacteria, were shown to have an impact on one or more of the kinds of bacteria that live inside us. Of course, the gut microbiome is a complex community of microbes, so we still need to find out whether these effects hold true in the body, as well as in the lab.

Interviewee: Lisa Maier

At the moment, we just screened impure cultures, so in isolation, but the picture might look way different in bacteria communities. There might be for example, that some bacteria secrete an antidote, and of course, will protect everyone in the community. These kind of effects, so cross-sensitivity and cross-protection, these kind of effects we would miss in our screen. And of course, the results have to be verified and tested in vivo, like in animal models, pharmacogenetic studies, and also clinical trials. And of course, also mechanistic understanding would be very helpful.

Interviewer: Shamini Bundell

At the moment, the mechanisms by which non-antibiotic drugs might be influencing bacteria are a bit of a mystery.

Interviewee: Lisa Maier

For example, for antipsychotics, they are supposed to target serotonin and dopamine receptors in the brain. It’s not very obvious on what’s the target in bacteria cells.

Interviewer: Shamini Bundell

All of these unknowns raise some worrying prospects, as Lisa explains.

Interviewee: Lisa Maier

There are several aspects of the study that are worrisome. Of course, the fact that a lot of drugs that we take on a daily basis have an effect on our gut microbiome, but I guess the most worrisome aspect is also that we find that anti-biotic resistance mechanisms are shared between antibiotics and human-targeted drugs.

Interviewer: Shamini Bundell

What Lisa and her team noticed, is that bacteria then tend to be resistant to impact from various human-targeted drugs, also tended to be resistant to antibiotics. Now they don’t know why this correlation exists, but it could mean that certain non-antibiotic drugs could increase bacterial resistance to antibiotics, which is something that clearly needs investigating. But whether or not that’s the case, the influence of non-antibiotic drugs on human gut microbiomes is something that could affect a lot of research, and will undoubtedly be the subject of a lot more study.

Interviewer: Benjamin ThompsonWell, thank you there Shamini. That was Lisa Maier from the European Molecular Biology Laboratory in Heidelberg. You can find the paper at nature.com/nature.

Interviewer: Shamini Bundell

Later in the show, we’ll be joined by Davide Castelvecchi for the New Chat, where we’ll be hearing about the winner of this year’s Abel Prize and children’s drawing of scientists. First though, it’s Research Highlight time with Ellie Mackay.

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Interviewer: Ellie Mackay

Scientists are shining a light on fermentation, literally. The technique of optogenetics, using laser light to activate neurons, has long been used in neuroscience. But now scientists have developed a different use for these precise light beams: switching on yeast fermentation. The metabolic pathway behind fermentation requires incredibly fine control, and the relevant proteins involved need to be produced in the yeast at the right time, and in the correct order. This means that the process is not particularly efficient at an industrial scale. Now, scientists are using the optogenetic laser technique to activate the production of these proteins, using a pulsed light to induce metabolic enzyme expression. This allows switching instantly between the growth and production phases in the yeast, leading to automated and more efficient yields of biosynthetic products like biofuels. So, industrial production might one day be a laser lightshow. If you found that story illuminating, head on over to Nature for more.

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Interviewer: Ellie Mackay

If you think that modern art stinks, it turns out you’re right! A team of researchers at University College London has been sticking their noses into the art world. With modern artworks increasingly made with materials like PVC and acetate, curators need a new way to assess a piece’s condition without damaging it. Well, it turns out the plastics emit odorous molecules as they degrade, and these can be detected in the air. The team uses a vapour-sensitive catchment strip to catch the gases, to detect an artworks odour profile. The technique has been tested on some smelly sculptures at the Tate Modern gallery in London, with the results showing the scent signatures of the pieces related strongly to their age and degradation levels. The method could therefore be used to detect and prevent decay in valuable modern artworks. To read more, sniff out a copy of Angewandte Chemie International Edition.

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Interviewer: Benjamin Thompson

There are various ways you can scan a brain. For example, there’s the CT scan which uses x-rays to see the brain’s structure, FMRI scans, which reveal changing blood flow in different parts of the brain, and MEG scans, which reveal the electrical activity of neurons. MEG stands for magnetoencephalography, which is easy for me to say, and it’s been around for decades. Now though, the technique is being improved upon. Reporter Noah Baker has been speaking to Matt Brookes about the new developments, and started off by getting a description of how MEG actually works.

Interviewee: Matt Brookes

Your brain’s electrical, so it communicates with itself and with the rest of your body, by the passage of very small electrical currents. Those electrical currents in your brain generate magnetic fields, and those magnetic fields persist outside the head. So, in MEG what we do, is we measure the magnetic fields outside the head that are generated by the brain, and then we use those magnetic fields to reconstruct images of current flow through the brain, so in other words it’s a measure of brain function, so it’s a measure of what your brain’s doing, basically.

Interviewer: Noah Baker

Tell me a little bit about the machines that are conventionally used to do MEG.

Interviewee: Matt Brookes

The conventional machines are cryogenically cooled, they’re very large, they look like a sort of huge helmet that stands a metre and a half, two metres above the subject, and the subject has to sit, effectively with their head inside this helmet. And you have to keep very still, even a 5-millimetre movement of your head relative to the scanner can make the data unusable.

Interviewer: Noah Baker

And so, you’ve tried to approach these limitations, to try to tackle these limitations, by creating a new form of MEG. Tell me what you were trying to solve.

Interviewee: Matt Brookes

Our approach was to say well can we turn this massive machine into, effectively, something that can be worn on the head like a hat. That was made possible, there’s been rapid progress in the area of quantum sensors, and in particular, a very exciting new quantum sensor called an optically-pumped magnetometer, or an OPM. And what our aim was, was to integrate those sensors into our helmet. And because they were small and lightweight, they could be integrated into a helmet in such ways to allow the subject to move around whilst they were being scanned.

Interviewer: Noah Baker

And so, kind of fundamental to this, is this helmet. I’ve seen pictures of it. I have to admit I laughed when I first saw it, it looks a little bit like a luchador’s mask with these sensors coming out of the back which are sort of Predator-esque. Tell me a little bit about how you make that helmet and how you attach these sensors to it.

Interviewee: Matt Brookes

Some people says the helmet reminds them of Phantom of the Opera, other people say Game of Thrones. I’ve never seen Game of Thrones so I don’t know what it’s about. So, the approach that we took, the helmet itself is 3D-printed, and it’s 3D-printed based on an individual’s MRI scan.

Interviewer: Noah Baker

And you’ve made this prototype, tell me does it work? Is it going to give you the kinds of readouts that you would get from a conventional MEG machine?

Interviewee: Matt Brookes

The results that it gives are actually better, so because we’re getting closer to the scalp, we’re getting an increase in sensitivity. We’ve shown that it gives an increase in spatial precision. We can more accurately find out which parts of the brain are engaged in a particular task. And, the really important thing is actually we can do that whether or not the person was moving around.

Interviewer: Noah Baker

So, your machine uses this helmet, or this sort of mask, that’s based on a 3D print of a scan of one individual person, so you can get these great readings, but at the moment it works with this one person, and I’m assuming you want to be able to use this machine with more than one person. That doesn’t sound like it’s very transferable to other situations.

Interviewee: Matt Brookes

I would stress, it is a prototype helmet, we obviously realise that it would be completely impractical to build something like that for every single person that we scan with this thing. So, our future research is looking at making that helmet much more practical for scanning kids, and for scanning adults, actually. We want to turn it into something that’s much more similar to a sort of bike helmet, something like that.

Interviewer: Noah Baker

So, one of the big advantages of this technology that you’ve developed, is that a subject is able to move while they wear it. Now, that movement can also cause some problems when it comes to getting your readings, especially with relation to the Earth’s magnetic field.

Interviewee: Matt Brookes

So, one of the problems, is if you move a magnetic field sensor through the Earth’s magnetic field, it obviously detects that movement. So, it detects the change in the Earth’s magnetic field as you move or rotate through it. And those signals are much larger than the signals we get from the brain, so we need to be able to remove that Earth’s magnetic field almost completely in order to allow the subject to move, and that’s one of the key pieces of technology that’s actually been developed here. So, what we’ve got is a set of electromagnetic coils, now those coils sit either side of the subject, they’re a reasonable distance away so the subject’s not claustrophobic, but what those coils do is to remove the effect of the Earth’s magnetic field around the subject. And they do that in a 40 by 40 by 40-centimetre box.

Interviewer: Noah Baker

So, you are sort of creating, you know this, 40 by 40 by 40-centimetre cube of sort of magnetic dead space.

Interviewee: Matt Brookes

Exactly, yes, that’s right.

Interviewer: Noah Baker

And your sensors will work, so long as they’re within that space.

Interviewee: Matt Brookes

So, I should say, that 40 by 40 by 40-centimetre box is actually limited only by the fact that we had to build this thing around an existing cryogenic MEG system. We could make that box bigger, and we hope that by future iterations, future development on the coil technology, we’re going to be able to not just allow people to move inside this box, hopefully they’ll be able to walk around. And so, that bring in the possibility of doing things like virtual reality, so you could imagine wearing a virtual reality headset whilst also having an OPM-MEG system on your head.

Interviewer: Noah Baker

After speaking with Matt, I wanted to gauge just how his machine could really have an impact, both in research or in a clinical setting. So, I reached out to Sylvain Baillet from McGill University in Montreal. Sylvain specialises in brain imaging, in particular, MEG.

Interviewee: Sylvain Baillet

If we have the joint benefits of high spatial and temporaral resolution of state of the art MEG, and combine with the ability for the participants and the researcher to express and observe different body postures, that’s a very big leap forward in terms of exploring more the relationship between brain and behaviour, brain and body movements. All of these being very important in significant scientific questions that we are actually constrained by the reality of brain imaging scanners so far.

Interviewer: Noah Baker

Sylvain also referenced the cost of the machine; this new MEG is expected to be significantly cheaper than conventional machines.

Interviewee: Sylvain Baillet

I think the benefit, both in terms of allowing more body movement, and also in terms of cost reduction or at least expected cost reduction, is just gigantic. And I think that makes the outcome of this research and this publication very special and a milestone in brain imaging technology.

Interviewer: Shamini Bundell

That was Sylvain Baillet at McGill University in Montreal talking to Noah Baker. Before him, you heard from Matt Brookes of the University of Nottingham. You can find the paper at nature.com/nature, and we’ve also got a video on this new finding, so if you want to see the Phantom of the Opera style MEG helmet for yourself, head over to youtube.com/naturevideochannel.

Interviewer: Benjamin Thompson

Finally then this week it’s time for the News Chat, and I’m joined in the studio by Davide Castelvecchi, one of the reporters here at Nature. Thanks for joining us Davide.

Interviewee: Davide Castelvecchi

Thank you for having me.

Interviewer: Benjamin Thompson

Right then, well our first story today is about a recently awarded mathematics prize. Davide, maybe you could tell our listeners what it is, and who’s won it.

Interviewee: Davide Castelvecchi

It is the Abel Prize, and it is awarded every year since 2003. It’s been modelled after the Nobel Prize, but as most of our listeners probably know, there is no Nobel Prize for mathematics. And the winner this year is Robert Langlands, who has semi-mythological status amongst mathematicians because he came up with what a lot of people regard as a sort of grand unified theory of mathematics.

Interviewer: Benjamin Thompson

Yes, and that seems like a heck of a thing to have come up with, a grand unifying theory. Maybe you can explain to our listeners just a little bit about what that is.

Interviewee: Davide Castelvecchi

It depends who you ask, and it depends in what historical period. So, he came up with the original set of conjectures in 1967, and his idea was that there would be some kind of hidden correspondence, some kind of way of translating problems from one field of mathematics in to another one, and specifically it was from algebra and number theory into analysis.

Interviewer: Benjamin Thompson

So, a little bit of a Rosetta Stone then, if I can be reductive.

Interviewee: Davide Castelvecchi

Yes, exactly, and it’s a Rosetta Stone that allows you to go from one language to another, which means that sometimes a problem that is very hard to solve in one particular branch of mathematics, all of a sudden you have this kind of teleportation mechanism that transports you into a different branch of mathematics, where maybe the problem becomes solvable.

Interviewer: Benjamin Thompson

And what’s that been used for then?

Interviewee: Davide Castelvecchi

So, first of all it was greatly expanded, and it’s become beyond recognition, like there’s parts of this so-called Langlands programme that Langlands himself admits he doesn’t understand, and there are some that he is openly against. But people have found inspiration from his work to, for example, prove conjectures were actually pre-existing, so there’s been some open problems, some of them very important, that turned out to be special cases, you know particular cases of his conjectures. And one of them is the famous Fermat's Last Theorem.

Interviewer: Benjamin Thompson

So, Davide, this award for Robert Langlands is clearly in recognition for his work, and he’s been working on it for a very long time.

Interviewee: Davide Castelvecchi

Yes, on and off since 1967 at least. He was a very young visiting professor at the Institute for Advanced Study, and he approached André Weil who at the time was the star of number theory, an Langlands said, oh I would like to tell you about these ideas I have and he started, you know, basically chasing him down the hallway, and Weil said why don’t you just write me a letter and put it in writing, which basically it was a quick way to get rid of him, right. And then, Langlands took him literally, and he went and wrote a 17-page letter which he prefaced saying if you’re willing to read it as pure speculation I would appreciate that, if not I’m sure you have a waste basket handy.

Interviewer: Benjamin Thompson

Clearly it wasn’t thrown away then, and here we are, I mean, where does Robert Langlands stack up then in the kind of mathematical world.

Interviewee: Davide Castelvecchi

His ideas have dominated a number of branches of mathematics, and his name pops up everywhere, and it pops up in particular because of the depth of these connections that he first unveiled. Is he the greatest mathematician alive? I don’t know, but some people would probably put him in their top 10.

Interviewer: Benjamin Thompson

But a deserving winner none the less?

Interviewee: Davide Castelvecchi

I think if you ask most mathematicians, they’ll say that it’s hard to find a mathematician who is alive now who is so influential as Langlands was.

Interviewer: Benjamin Thompson

Well Davide, let’s move on to the US for our second story this week, and it’s one that suggests that children’s perspectives on what a scientist looks like might be changing.

Interviewee: Davide Castelvecchi

Yeah, so this is kind of a meta study. What the researchers did, was they looked at how children represent scientists. So, you ask kids to doodle a scientist and you see what happens and you count how many kids draw a female scientist, and how many kids draw a male. And they looked at studies from the 1960s all the way up to 2016.

Interviewer: Benjamin Thompson

I might not be quite that old, but I reckon that if young Benjamin had been asked to draw a scientist, there’s probably a good chance he would have drawn a male, in a lab coat with frizzy hair.

Interviewee: Davide Castelvecchi

Yeah, and it probably is true that a lot of people, a lot of children especially, will just go by what they’ve seen, by the kind of stereotypes they’ve been exposed to. But interestingly, I mean, it seems like there’s some very slow progress. So, in the 1960s and 1970s, there was virtually all children who drew a male scientist. Then if you go to the more recent studies, it’s gone to 72% from almost 100%. So, it’s very slow progress, but nonetheless, now one time out of three or four, the child will draw a female scientist.

Interviewer: Benjamin Thompson

Well Davide, while that’s potentially the start of a positive trend, it’s not all good news.

Interviewee: Davide Castelvecchi

It’s very interesting, if you look at how these studies break the data down by age, and it seems that as a child grows, their preference for drawing male scientists increases, so maybe they start out less bias, the more they age the more they tend to draw males.

Interviewer: Benjamin Thompson

Have the researchers behind it offered any ideas as to why this shift in young children might be?

Interviewee: Davide Castelvecchi

They do speculate that there’s a slow shift in perception because we do see women in science, in the media and in television shows and so on, has improved in science, certainly since the 1960s. The question is do we have lingering biases that cause children to have skewed perceptions which also leads to fewer girls going in to science in the first place?

Interviewer: Benjamin Thompson

Thanks Davide. For more on these stories don’t forget to head over to nature.com/news.

Interviewer: Shamini Bundell

And, talking of news, we’ve got some more exciting science stories for you over on our YouTube channel. As well as the MEG helmet story that we mentioned earlier, we’ve got a film presented by Lizzie Gibney about the wonder of masers. Well, what are masers? You’re going to have to go to youtube.com/naturevideochannel to find out. Well, we hope you’ve enjoyed this week’s podcast, and if you have don’t forget to tell your friends, tell your neighbours, and tell the world via a review or some stars on your podcast provider of choice. I’m Shamini Bundell.

Interviewer: Benjamin ThompsonAnd I’m Benjamin Thompson, thanks for listening, see you all next time.