Meet the panel: yam beans & facemasks

Before we get into the questions, it's time for Phil Sansom to introduce the panel...

Phil - Let's start with Nadia. Hi Nadia. Welcome.

Nadia - Hello.

Phil - What have you brought in to show us today, to start with?

Nadia - I have a picture here of a part of a plant that I'm studying. This particular crop is actually a forgotten crop or underutilised, or another term for it is orphan crop, which is a crop that used to be consumed traditionally, in this case, in Africa.

Chris S - Do you want me to describe for you? Because this looks like a bunch of roots and some of the roots have got bulgy bits on them, so it's almost like a root has swollen up and become very fat. How big are these things?

Nadia - A little bit bigger than an apple, I would say.

Chris S - Quite large then. Can I hazard a guess? Emma what do you reckon those are?

Emma - They look a little bit like sweet potato or something like that.

Phil - Yeah. Is it a yam, or a potato or something?

Nadia - So it is a tuber, so sweet potatoes and I guess yams, they are modified roots. However, this particular plant is in a legume family, so it's a completely different plant family than potatoes or even sweet potatoes. And it's called African yam bean.

Phil - And this is something that's been rediscovered and that you're looking to -

Nadia - Yes. So because it's a forgotten crop, it's an orphan crop. It used to be consumed in, in Africa, but now only the rural areas are still growing them. Poor farmers actually grow them for security crops. But now I'm studying them because nothing is known about this particular plant.

Phil - A rediscovered crop. Awesome! Well let's move on because next to Nadia we've got Chris Rogers who's a particle physicist. Hi Chris.

Chris R - Hi. So actually I'm an accelerator physicist. Oh, that means I design particle accelerators. There is a subtle difference.

Phil - Well, what have you brought in to show us?

Chris R - So in fact, what I brought in is a little bit of a particle accelerator, so I'll show it to the other guests. It looks like a small black foil. So it's, it's about the size of a very small playing card and it's actually one micron thick, so about the same thickness as a bacterium. And it's actually how we get our beam into our particle accelerator.

Phil - What's it made of?

Chris R - So it's made of carbon.

Phil - So that's an extremely thin sheet of carbon?

Chris R - Extremely thin sheet of carbon.

Chris S - What does that actually do?

Chris R - So what we do, when we want to get our beam of particles into our accelerator, it's really hard. So imagine when we start off with our particles, we just start off with a gas bottle with hydrogen gas, and we put a spark across that hydrogen gas and it makes ions come out. So we ionise the gas. We accelerate that beam up and then we want to get it into a ring accelerator. If we put protons into that ring, then as the protons come back round to the start again, those protons would knock into each other and we wouldn't really be able to get the protons into the ring properly. What we do is we accelerate a special sort of iron called an H minus ion. So instead of having a proton, we have a proton with two electrons attached. When those H minus ions go through this really thin foil, it knocks those electrons off. And then we can bring those protons around in our ring.

Chris S - So it's basically traffic management for particle accelerators.

Chris R - That's exactly what it is.

Phil - Let's definitely come back to this area, but for now we've got Emma Pomeroy, third in our panel. Emma, welcome. What have you brought? You're a bio archeologist.

Emma - Yes I am. Yes. And I've brought with me a cast, so a replica, of a Neanderthal skull in an individual that we know as Shanidar 1. So it comes from the site of Shanidar cave and Iraqi Kurdistan, which is where I'm currently conducting excavations. But this chap was actually found back in the 1950s.

Phil - That's amazing. It looks very, very much like a human skull.

Emma - And actually Neanderthals were pretty similar to us over all. If we look at the whole kind of span of the evolution of our species and our lineage, they're not so far away from us. They are sort of more robust in their brow ridges and in their face and the middle of their face projects a bit more. Critically, they didn't have a chin. So one of our modern human characteristics is that we have a really prominent chin and Neanderthals didn't. But other than that they look pretty similar to us.

Chris S - Can I just ask, when did they first appear?

Emma - Well that's a good question. We see species that have some of their characteristics from about 450,000 years ago. So we think probably sort of about 300,000 years ago or perhaps a little more more recently. So about the same time as modern humans did actually.

Chris S - So was there a sort of split in the evolutionary tree then? So our ancestors are both Neanderthals and anatomically modern humans like us, and they sort of went their separate ways and there was a path that took them down the Neanderthal line and a path that became us.

Emma - Exactly. So if you imagine sort of going back before our direct ancestor and before the direct ancestor of Neanderthals, our ancestors before that actually diverged. So some of them moved out into Europe and eventually evolved into Neanderthals and some of them stayed within Africa and eventually evolved into modern humans. And then after that, modern humans spread out into Europe and into Asia and Neanderthals eventually when mostly extinct apart from the little trace of DNA that many of us carry today.

Phil - Finally on our panel we've got what should be quite a familiar voice to many of you listeners, this is Chris Smith, a virologist at Cambridge. Chris, how are you?

Chris S - Yeah, I'm good.

Phil - How does it feel to be on the other side of the desk?

Chris S - I'm pretty nervous because we're going to do the quiz and I always take great delight in humiliating all the guests and you've made me a panelist! We should say the reason you made me a panelist is because you know the world is in the grip of what we're trying not to call a pandemic. So we thought it might be quite interesting for people to have the opportunity to ask some questions about this new coronavirus that's circulating. Because I've been doing quite a bit of that so I thought it would be very nice to help people if they want to ask anything about that.

Phil - Now's the time actually! Let me just throw it to the other three of you. Do any of you have a perspective or a question that you want to share or ask Chris?

Emma - We hear lots of advice about things we should and shouldn't be doing to avoid catching coronavirus and spreading it. So do face masks work? Do hand gels work?

Chris S -  Are you doing anything different?

Emma - Not really cause I'm always careful about washing my hands and that kind of thing. But should I be?

Chris S - Is anyone in here doing anything different, Chris?

Chris R - I had a cold on Friday so worked from home but maybe that means you guys need to stay away from me.

Chris S - Do you like the way he's come in and turned up at the studio? Sat down opposite all of us, shaken all our hands and now he's telling us he's got a cold!

Phil - I accidentally drank from Chris's water glass half a second ago.

Chris R - We'll wait for you to cough later on.

Chris S - The answer to the face mask question is actually probably just save your money. So the face masks that are not the ones used in hospital are not effective and that's for two reasons. One is that people tend to use them wrong. They put them on, take them off, put them on, take them off, touch all over them. For instance, when they want to eat and drink things and that transfers virus particles from the surfaces they'd been touching probably to the inside of the mask when they touch it. So it automatically brings the virus close to their face where they're trying to keep it away from. The other is that they quite quickly get damp because of the water in your breath and this means that the particles of virus can pass through the gaps in the mask quite efficiently. And also the masks don't have a very good stringency. There are big gaps between the fibres which, to the something on the scale of a virus, which is about one 10000th of a millimetre across, that's like the tunnel under the Thames. It's absolutely huge. So no obstacle whatsoever for the virus.

They also don't tend to be worn properly. People leave big gaps around the sides. So when you breathe out or breathe in, it just pulls air in from the room and into the side. So that's probably a no for masks, I would save your money. I've said to somebody, go and buy a beer instead because you'll enjoy having that in your mouth more than the mask. It'll probably cost you less based on the amount of profiteering that's going on at the moment. And it will give you equivalent if not more protection from the virus. It will also be more fun.