STEMology s1e17

Intro

[00:00:00] Sophie: [00:00:00] Welcome to episode 17 of STEMology

[00:00:03]David: [00:00:03] A podcast, sharing some of the fun. Interesting, and sometimes just patently bizarre news in science, technology, engineering, or maths.

[00:00:10]Sophie: [00:00:10] Your hosts are Dr. David Farmer and Dr. Sophie Calabretto

[00:00:14]David: [00:00:14] This week, we are speaking about quantum Robbins, cloning bees,

[00:00:17]Sophie: [00:00:17] gray hair, and the difference an audience can make

Quantum Robins

[00:00:21]Quantum robins, Dave

[00:00:23]David: [00:00:23] Quantum bloody Robbins. Right? So this is all about how we know wherever we’re going. Right? Like I know where I’m going sometimes, but I have fancy tools to do that. I have like Google maps and I have, you know, if I was really stuck, I would have a compass.

[00:00:38] that would tell me where to go, but somehow the European Robyn can get all the way from cold ass Russia to the warmer Western south of Europe, how the hell did they do that? Sophie?

[00:00:49] Sophie: [00:00:49] Well, Dave, they use a quantum sensors, which I’m sure you don’t have. Yes, I say so basically what we’re talking about here, Dave is vision-based Magnetar [00:01:00] reception.

[00:01:00] David: [00:01:00] Ooh

[00:01:00] Sophie: [00:01:00] So it talks about the ability to sense the magnetic field of the earth for navigation. Affected by light entering the eye, but we’re not talking about classical light as in the classical physics sense of light.

[00:01:13] We’re talking about quantum light or yes, kind of. so Robbins tape is just a Robins can go real far. Um, and apparently they do a lot of then migration in the dark.

[00:01:24] David: [00:01:24] That’s right! Yeah.

[00:01:24]So you’ve got these birds that are migrating great distances, and you say, well, maybe they look at where the sun is, but they do it at night. So it can’t be that. So it must be something else. And I want to tell You,

[00:01:33] this, because this is really exciting to me. And I get this from a book called, Life On the Edge of The Coming Age of Quantum Biology by Jim El Khalili and everyone should read it because it’s

[00:01:41] Sophie: [00:01:41] uh, Jim, I know I’ve seen a couple  of documentaries. And in fact, I think you wrote a book about prime numbers. Once

[00:01:47] David: [00:01:47] Yeah. So he writes this great book about quantum biology and the fact that birds migrate or that homing pigeons home using the Earth’s magnetic field is one of very few instances in biology where you have to invoke quantum theory. But even before that, [00:02:00] working out that bird sends the Earth’s magnetic field that goes back to like the 1940s, fifties to this guy called Henry Yeagley, who was an American physicist working around the time of the second world war. And he works for the army signal Corps because they wanted to understand how the hell homie birds homed, because they wanted to like take advantage of that mechanism whatever it was.

[00:02:19] So he devised this kind of mean, but beautiful experiment where

[00:02:24] Sophie: [00:02:24] Tell me tell me about it.

[00:02:26] David: [00:02:26] He got 20 homing pigeons, right? And he either put strips of copper or strips of magnetically, active material on their wings and then took them away and then let them go. And eight of the birds with copper came back, but only one of the magnet birds came back.

[00:02:43] So the suggestion is that the magnets on the side of the birds disrupt its ability to hold them back to where it was suggesting that they’re sensitive to their it’s magnetic fields. A very mean, but very beautiful experiment.

[00:02:55]Sophie: [00:02:55] Yeah. that’s harsh. I feel like we do mean things to animals, sometimes for science. Um, but yeah, so what [00:03:00] we want to talk about Dave is a cryptochrome protein complex in the eye of these European Robins. So it’s specifically cryptochrome four or cry 4. And so this allows this non-classical response to light, but we sort of have to backtrack.

[00:03:15] So apparently there was work earlier this year that was actually done in the human eye and it told us some things and gave us these suggestions about how they could impact birds and migratory animals. And so work earlier in the year came from the University of Tokyo and they found that a similar protein in humans could respond to blue light in different ways, depending on the strength of the nearby magnetic field. And then this is where we’re getting into some particularly physicsy stuff, which I will try to very succinctly sum up in a way that doesn’t make anyone’s brains melt. But right Dave there are certain atoms in this protein with a lone electron in the outer shell, because it has a lone electron in the outer shell, the solitary electron can be paired with another solitary electron in what is [00:04:00] known as a radical pair. So a radical is just a molecule with an odd number of electrons.

[00:04:05] David: [00:04:05] right.

[00:04:05] Sophie: [00:04:05] So.

[00:04:05] David: [00:04:05] A radical pair, I supposed to like a tubular triplet or a singular

[00:04:10]Sophie: [00:04:10] Yes. Exactly. So we’ve got this radical pair, because we have one electron in the shell of both of these things we compare together makes an radical pair, but they become entangled. Right. So, and by entangled, I mean, quantum entanglement. So the first thing that I need to talk about in terms of the radical pair is that, both of these radical pair, electrons have spin, right?

[00:04:32] So when we say spin in particle physics. We may have spin angular momentum, which is just a kind of intrinsic angular momentum that elementary particles have. And I don’t want to talk about it any further, but the idea is because they have this spin angular momentum, each separate radicle creates a magnetic moment.

[00:04:49] So a magnetic moment just think about magnetic fields with directions. So it’s the idea. It’s the magnetic strength and orientation of a magnet or other objects that produce a magnetic fields. It’s [00:05:00] vector magnets. Because we have vector magnets. It means that this spin states can be altered by the magnetic field.

[00:05:06] So we’re creating a magnetic field. If it’s in a magnetic field they’re going to interact. So that’s the radical tubular part of this protein.

[00:05:13] David: [00:05:13] Right.

[00:05:14]Sophie: [00:05:14] Because there are two of them, they become quantumly entangled. So the idea of quantum entanglement in a nutshell is that we’ve got two entangled particles.

[00:05:22] They remain connected in a magical, spooky way. So when you do one thing to one, it affects the other one, even if these are at great distances.

[00:05:32] David: [00:05:32] Which doesn’t make any sense in terms of classical physics. in terms of simple things, like cause preceding effect, it doesn’t make any sense to us whatsoever.

[00:05:40] Sophie: [00:05:40] and it leads to like a bunch of paradoxes. So the most, I guess the most relevant one is the EPR paradox, which is the Einstein Podolsky, Rosen paradox. We’ve got two entangled particles and under the Copenhagen interpretation of quantum mechanics, each particle is in an uncertain state until we measure it.

[00:05:57] So there’s this thing in quantum mechanics is working. You don’t know what the state’s, [00:06:00] something is in until you measure it. And then once you’ve measured it, the state becomes certain. But because they’re entangled, when you measure the state of one of them, it becomes certain then you know, the state of the other one because they’re entangled.

[00:06:11] But the problem is that happens instantaneously. And the reason that that’s a paradox is that involves communication between two particles at speeds, greater than the speed of light, which is then in conflict   Einstein’s theory of relativity. So anyway, we’ve got entangled particles and they’re affected by magnets.

[00:06:27] Okay. this is all we need to know about these proteins in birds eyes. And so the nature of this partnership is then affected by the magnetic field. And so what they found is, and this is again, we’re still sort of inhumanized, if we strike this protein with a specific dose of energy and they’ve done it in the form of blue light.

[00:06:46] And I can only guess it’s blue light because that’s just quite a high energy light.

[00:06:50]David: [00:06:50] I think it has to be blue light. I think it doesn’t work with red light,

[00:06:53]Sophie: [00:06:53] Well yeah definitely not red.

[00:06:55] David: [00:06:55] Yeah. I think it’s specifically blue light that does it.

[00:06:57]Sophie: [00:06:57] Okay. So blue light does it. and so what the [00:07:00] people at the University of Tokyo found was that the radical pair will fluoresce in different ways, depending on how they’re entangled.

[00:07:06]Right? So that quantum nature of the relationship between the two electrons can cause the light to signal different strengths of a magnetic field. so Because of the magnetic field, the way that we strike it with light, we’ll get different kinds of fluorescents. And that can tell us about the differences in the magnetic field. And so they thought that, you know, in this human eyes, this could then explain how some animals like migratory birds might sort of see the alignment of field lines and they can sort of distinguishing the planet’s magnetic compass point.

[00:07:35]David: [00:07:35] Yeah, so basically what this allows the birds to do is to detect the angle at which the magnetic field is entering into the earth. So it’s called a magnetic declinometer. So it’s not like a compass, which points towards north, what this does is give them a sense of the angle at which the magnetic field lines are going into the earth.

[00:07:53] So basically they can tell which direction the nearest pole is, but not what pole it is. [00:08:00]

[00:08:00]Um, which makes it a bit complicated. And again, there were some quite mean, but again, very beautiful experiments where they put some animals into a box. Um, and then basically my understanding is it’s like an ink pad at the bottom of the box.

[00:08:12]what that means is that when the animals try to climb the walls to escape, what they’ll find is that no matter which way you orient the box, they would preferentially orientate themselves along the earth’s magnetic field. So parallel to the earth’s magnetic field. And there’s also some like, magnetic sense, but it needs these cryptic chromes and they need light.

[00:08:31] Sophie: [00:08:31] Yeah.

[00:08:31] David: [00:08:31] And that was a whole other discovery as well. Right. so that was, again, really simple, beautiful experiments with homing pigeons, not European Robbins, now but homing pigeons where If you take a homing pigeon and put it in a box with a magnet, like a magnetic field,

[00:08:46] Sophie: [00:08:46] If you were to do that.

[00:08:47] David: [00:08:47] if you were to do that and then take it away from its home risks and release it, it struggles to find its way home and the implication of that is that they’re using their its magnetic field to know where they’ve been taken.

[00:08:57]Sophie: [00:08:57] Uh,

[00:08:58] David: [00:08:58] the light thing comes in as well, because [00:09:00] the same thing happens. If you put homing pigeons in a box that doesn’t let light in and then take them away from home roost, same thing happens.

[00:09:08] They struggle to find their way home. So there’s an implication there that A, the homing pigeons can sense the Earth’s magnetic fields and B that the process needs light. And then that’s when people started looking for these weird funky magnetically sensitive proteins, crypto chromes, which also need light to work.

[00:09:25] Sophie: [00:09:25] Yeah. And so what this most recent study did is actually use, pigeons, but they also use chickens and then they use Robbins as well. So the idea was, you know, we’ve got this Robin, which is the migratory bird. We’ve got a pigeon that is, you know, very good at finding its way home, over long distances, but it’s not technically migratory..

[00:09:41] And then they’ve got also a chicken and there was a joke in the press release. Uh, chickens are not known for taking journeys anymore, arduous than crossing the occasional road.

[00:09:49]David: [00:09:49] Oh guys.

[00:09:51] Sophie: [00:09:51] And so what they did is they did these tests. So again, in and outside magnetic fields, flashing blue light, or having continuous blue light, you know, at these crypto [00:10:00] chrome.

[00:10:00] And they found that, basically. The Robbins were more sensitive. So the test suggests that the crypto chromes and the Robbins can sense subtle influences of the Earth’s magnetic field. Just more so than chickens and pigeons, but they still need to carry out further studies to confirm sort of those quantum actions of the cryptochrome in the sense that is it, that that actually helps them navigate.

[00:10:22] David: [00:10:22] Yeah. so the kind of what’s really been done in this paper is they’ve shown a very basic association between the stronger cryptochrome, which is more sensitive and the migratory behavior of the Robin versus the chicken.

[00:10:34]Sophie: [00:10:34] But yeah, um, complex, eye proteins quantum light blued navigate. There’s a lot of stuff. it was really interesting, but yeah, just, I mean, just nature. What

[00:10:45] David: [00:10:45] Nature. It’s radical.

Cloning Bees

From birds to bees. Sophie. And not just [00:11:00] from birds to bees, but from navigating in the dark European Robbins to immortal bee clones of death.

[00:11:05]Sophie: [00:11:05] oh my God. I really liked this. is it’s just, sometimes you go what a, as I said, what is nature doing? We have these clone armies of rival bees who are collapsing the hives of African lowland honey bees from the inside out by basically making lazy freeloading clones.

[00:11:23]David: [00:11:23] Yes. So this is the victim bee we’re describing here as the African lowland honeybee and the invasive bee is the south African Cape honeybee. And you may have your own team preference at this stage already, dear listener, I don’t know, but basically the south African Cape honeybee, the invasive bee can create perfect copies of itself with one individual from the nineties found to have done so millions of time in the past three decades, invading the colony of the African lowland honey bee and causing the hives to collapse, basically through [00:12:00] just nonsense, like just making a bunch of nonsense bees that don’t pull their weight.

[00:12:05] Sophie: [00:12:05] Exactly. I really liked this because it reminded me of the blue eyed story we did, where we had sort of like one mutant in the past who had blue eyes. Now everyone has blue eyes. Now he had one jerk honeybee in the nineties who apparently has created this lineage of jerk clones who are responsible for something insane.

[00:12:23] Like. the collapse of 10% of the hives of these lowland honeybees. Like every single year.

[00:12:31] David: [00:12:31] Yes.

[00:12:32]Sophie: [00:12:32] so we need to talk about this cloning though, Dave, and this gets them to a level that is maybe a little bit above me, so there’s a new study and this has come out of the University of Sydney and basically has revealed the genetic foundation of this what they refer to is a strange and formidable adaptation. And it’s got to do with reshuffling DNA.

[00:12:51]David: [00:12:51] Yeah. And my understanding of it is fairly low level and psychomy but here we go. So basically you’ve got [00:13:00] two types of bees in both bee types, you’ve got worker bees and you’ve got queen bees.

[00:13:04] Sophie: [00:13:04] And we’ve talked about workers and queens before.

[00:13:06] David: [00:13:06] Yeah.

[00:13:06] that’s right. So the Queens reproduced sexually and the workers, it turns out, I didn’t know this, but all worker honeybees can reproduce asexually like they can just make copies of themselves, but in the African lowland honey bee which is the honeybee that doesn’t make scary clones, that kind of asexual reproduction can’t really go on for very long, because once you’ve gone a few generations down, just because of the way genetic reproduction works, you end up basically chucking out too much genetic material and you end up with a lack of genetic diversity that is low enough to be lethal to the bees. And I guess the shorthand of that is making a copy of a copy of a copy until you end up with something that’s indistinguishable as anyone who’s watched. The most recent episode of Rick and Morty will know. The south African Cape honeybee has, uh, a tweak and the way that it reproduces such that it avoids the step where the genetic material is lost, [00:14:00] which means that it can reproduce and reproduce and reproduce and copy and copy and copy, and copy until they’ve basically completely taken over the hive of another bee.

[00:14:09]so basically the central hypothesis of this paper was that if they looked at the genetics material of both the worker bees and the queen bees of this African type that the worker bees would have a genetic tweak that throws out the recombination part, of reproduction that leads to problems, um, the Queens wouldn’t because they reproduce sexually.

[00:14:28] So it doesn’t matter.

[00:14:29]Sophie: [00:14:29] Yeah. And so what they did is they got, a bunch of, well, they got one queen, and they examined certain DNA sequences of both the queen and the 25 larvae that she produced. And then they did the same for four Cape honeybee workers and their 63 larvae, and they basically, yeah, they discovered that the asexually reproduced offspring of the queen had levels of sort of recombinations.

[00:14:53]This DNA recombination a hundred times greater than the genetically identical cloned offspring of the workers, which is basically [00:15:00] it just that findings suggest that the Cape worker bees have evolved this mutation that prevents recombination.

[00:15:06] David: [00:15:06] Yeah. And did you read about how they forced? So they made the Queen’s reproduce asexually that you read about how they did that?

[00:15:12]Sophie: [00:15:12] a little bit, Dave, but i feel like you’ve read more about it and you seem a bit excited. So I want you to tell me.

[00:15:17] David: [00:15:17] it says very explicitly in the paper, and I love when it’s as low tech as this, they taped over the sexual organs of each queen so that they couldn’t reproduce. So this is a chastity belt brought to you by cellotape, basically.

[00:15:30] Sophie: [00:15:30] Uh, science, Um, and so basically then it leads to this kind of interesting behavior. So I learned about these things called queen cells, Dave. So queen cell is basically where a queen lays the eggs containing future Queens, but then also like a worker could fly in.

[00:15:45] replace the Queen egg with one of their clone eggs. And I love this bit. That way they can be genetically re-incarnated as a queen. Dave, I’d like to work out how I can be genetically reincarnated as a queen because it sounds very fun. But then yeah, this, that one [00:16:00] particular lineage of the Cape bees that we were talking about, they go further.

[00:16:04] So what they do is, as we said before, they go into the hives of these African lowland bees and they lay their eggs. And the problem is that these African lowlands bees mistake, you know, the eggs and the larvae for their own and they rear them. But then again, it goes even further. And we’ve talked about animals with their like jerk, like cuckoo behavior.

[00:16:21]So these Cape bee larvae even send signals to their host to feed them as much as possible. Right. And so, because they’re being fed heaps, it allows them to grow big and like their bodies and ovaries big enough to be almost the size of the Queens. And so then, because their ovaries is a big enough and they can reproduce and they don’t have to do any work.

[00:16:40] So basically they go in there and get super fat with giant ovaries. Everyone goes like, well, you’re a reproducer, you don’t have to do anything. And so now we’re field a hive with just like dysfunctional freeloaders, and then eventually like the hive collapses.

[00:16:55]David: [00:16:55] It’s brutal. So They make a really interesting, um, similarly here they say [00:17:00] that these bees, which are like, they’re not cells, they’re organisms, but they say these bees are a lot like the cells and a tumor in that regard. So it doesn’t matter. So because this, like it’s behaving in this way, even for an individual bee is not very good for it.

[00:17:12] So to behave in this way is not very good for it, but they kind of say it doesn’t matter if every clone has healthy so long as there are enough of them. Like a critical mass of them, any chive to exploit that hive. And then of course it’s the same as cancer. Like the tumor grows almost like an organism until it kills the host.

[00:17:28]similarly here, these dysfunctional bee sub colony grows and grows and grows until it kills the hive, but it’s just really weird to think of a whole animal behaving like a cancerous cell in that way.

[00:17:39] Sophie: [00:17:39] Yeah. and so I think the next step would be to figure out how the Queens can switch on the gene that enables the recombination and the workers can switch it off. But Dave, could you find out the why. why. do they do that? Is it just because they’re rival bee isn’t and they like, they’re going for the same stuff and this is

[00:17:55]David: [00:17:55] Um, maybe it was an accident, Sophie, maybe it was just, uh, I mean, maybe it was [00:18:00] just an accident and they’ve become almost like a parasitic bee so. I don’t want to get too much into the genetics I don’t really understand genetics, but a genetic accident that produces this reproductive behavior. And then one of them has happened to fly into the hive of another bee and reproduced, and then we’ve just got this critical mass of them though, So it’s the same as everything in evolution, because it’s successful, you see more of it, but it’s a really weird one because everything I was taught about evolution at, university suggests that the genetic diversity wins. So this is a genetically undiverse piece. The reason we have sexual reproduction and recombination is because genetic diversity is good for us because if something comes along that knocks out 10% of the population based on his genes, like a disease, then the other 90% of the population survives. Whereas if something came along like a disease or  parasite or something that could target this particular, the, um, south African Cape honeybee, like it would just wipe them all out because they’re genetically identical.

[00:18:56] So it’s not a particularly advantageous thing from a species perspective either. [00:19:00]

[00:19:00]Sophie: [00:19:00] So you’re suggesting that in order to protect themselves, the lowland honeybee should come up with some kind of virus that works on the lack of the genetic diversity of the Cape honeybees as their main source of defense.

[00:19:13]David: [00:19:13] I think that would work. And then the question would be, how do we identify the piece? How do we distinguish them? But because they’re all descendants of a single worker that lived in the nineties. So presumably they’re all wearing Nirvana t-shirts.

[00:19:24] Sophie: [00:19:24] Yeah.

[00:19:24]David: [00:19:24] And I think that provides us with a means of identifying them.

[00:19:27] And So eliminating them,

[00:19:28]Sophie: [00:19:28] So if, anyone from a Africa, low land hive needs some tips, please get in contact with STEMology, and we’ll help you create your virus.

[00:19:36]David: [00:19:36] and we’ll swap some grungy albums.

Grey Hair

[00:19:47]So Sophie from the birds and the bees to literally splitting hairs

[00:19:53] Sophie: [00:19:53] Dave you’re on fire today and I’m very worried. What are we talking about in terms of hair? Dave, tell me about your hair.

[00:20:00] [00:19:59] David: [00:19:59] So I I’ve got some gray hair. Sophie, do you have some gray hair?

[00:20:02] Sophie: [00:20:02] I definitely have some gray hairs Dave

[00:20:05] David: [00:20:05] if you’ve got some gray hairs, we both got PhDs. I think there’s probably a correlation there.

[00:20:09] maybe to do with stress.

[00:20:11] Sophie: [00:20:11] Maybe, yes. So this, I really liked the story because, and I’m just gonna, I’ve got a spoiler  right now, but I did a while ago, notice that I had a hair that went from brown to white, to brown. And I was like, what is that? Turns out. Possibly it is related to a stressful period in my life. So we have some work that’s come out of Columbia university, Irving Medical Institute, this new study offers quantitative evidence, linking psychological stress to graying hair in people.

[00:20:41]David: [00:20:41] Yes. this is some work by The study senior author is called Martin Picard’s, which I’d like to point out. It is quite close to being a Star Trek captain, but not all the way to being a

[00:20:50] Sophie: [00:20:50] I also thought about that straight away

[00:20:53] David: [00:20:53] Yeah. I feel like, being called Martin Picard is like being called Jeff Skywalker.

[00:20:56]it’s kind of part of the way there, but not the whole way there you’ve been [00:21:00] partially named after it. uh, so yeah, people have long believed that psychological stress can accelerate the appearance of gray hairs, but there’s been a lot of debate amongst scientists apparently about the connection, because we don’t have good sensitive methods that can precisely correlate times of stress with hair pigmentation at a single follicle level, which is what we really need to do if we want to make a strong connection between these two things.

[00:21:24] Sophie: [00:21:24] Yes. and so the idea here is that, you know, if you get stressed, your hair is not going to instantly turn gray and all of them. So when the head are still under the skin and as follicles are subject to the influence of stress hormones, right?

[00:21:36] Cause basically hairs are still inside of us. So things happening in our mind and body can potentially affect them. And then once the hair grows out of the scalp, then you basically get these, like the hair sort of hardened and permanently crystallizes in its form. Right. So the idea here is that if you’re being stressed, And you can align the stress to, as you said, a certain period of time, [00:22:00] you can then see if there’s any correlation between being stressed and the color of the hair.

[00:22:04] So what they’ve done is they have developed a new method for capturing highly detailed images of tiny slice of the human hair to quantify the extent of the pigment loss. And then the idea was in this group of people where they did this, they also got them to keep a very detailed stress diary then they managed to line these up with insane accuracy and they found that it was during these highly stressful periods, that there was this loss of pigment and hair turned gray.

[00:22:30] But then, also when that stress has disappeared, that particular hair strand went back to being the original colour.

[00:22:36] David: [00:22:36] Yeah,

[00:22:37] So they say they pick out one particular example where they say there was one individual who went on vacation and five hairs on that person’s head reverted back to dark during the vacation synchronized in time. And to clarify dear listener, they didn’t look at every hair on this person’s head.

[00:22:50] It’s just five of the hairs they happen to have. So that is actually probably reasonably good bang for buck. but what I really loved about the methods of this  paper is that they’d say they’d developed this new method [00:23:00] for looking at hair strands and what the new method is, is just looking at them really, really meticulously and carefully, um, because they don’t really use any  specialized equipment, but it’s not anything you wouldn’t find in a science lab. So they use a Panasonic for whole hairs, where first photograph using a Panasonic DCF, Z 80 digital inadvertent commerce camera.

[00:23:22]which I looked up, it’s a bridge SLR. It’s like not a fancy camera, but they’ve used it and done these very, very fancy.

[00:23:28]They’ve just taken very, very careful photos. And then they looked at it under a, in a very common microscope. And then they took two hairs and looked at them under a transmission electron microscope, which is a bit fancy. And then basically they took these pictures of the hair and gray scale them basically just looked at them in black and white and basically digitize them, such that they could look along the length of the hair and quantify not just large changes from dark to gray that we would see when we just look at our hairs, a very fine changes in pigmentation. [00:24:00] And what they reckon is that it takes some threshold amount of stress. Before you fully turn the hair gray and then the hair is no gray and you can’t ungray it right.

[00:24:11] Sophie: [00:24:11] Yeah. so in terms of the people they looked up, they just had 14 volunteers, but they looked at 397 individual hairs. That’s not a bad group of hairs, but what I really liked was, hairs were plucked manually or with standard flat tip tweezers from the scalp or other body regions and archived for future imaging or molecular analyses.

[00:24:32] And that worried me slightly, but we don’t need to go in there, in any great detail. But, um, yeah. it all comes down to potentially Dave, the mitochondria.

[00:24:41]David: [00:24:41] Yes. So the mitochondria, as we all know, are the powerhouses of the cell. Tiny little things in our cells that produce chemical energy for our cells to use. And apparently, I didn’t know, this apparently mitochondria are sensitive to stress hormones. So the mitochondria, when they’re increasingly active, like they might [00:25:00] be, if you were stressed, will produce things like  reactive oxygen species, which are kind of pro-inflammatory and, generally did believed to be not very good for the cellular environment and overactivity of these mitochondria as assessed in this study by looking at the proteins that were present and the follicle seemed to be increased in the gray hairs.

[00:25:20] So that’s what leads them to suggest that. So you get stressed, your mitochondria become more active. And then at some point of mitochondrial activation, the hair becomes irreversibly gray, and it never goes black again.

[00:25:32] Sophie: [00:25:32] Yes. So they looked in for changes in 300 proteins occurred when the hair color changed. And what they actually did is they developed a mathematical model that as you said, suggest the stressed induced changes in mitochondria may explain how stress turns hair grays. I had a quick look at the model, Dave,  it’s a full what they call a linear mixed model. So the idea is you’ve got fixed effects and then you’ve got random effects, which is good because like, we don’t understand exactly how hair grain works. So you need to [00:26:00] account for us to Castic or random effects. And so what they have is basically the fixed effects or your aging factor rate, which is like pretty clear how you’re aging and then also the stress sensitive rate.

[00:26:10] So we’ve been measuring stress, but then they’ve got random effects that have to do with aging factor and then stress sensitive. Right. And then also initial grain loading. So the idea is, if you are a one or two and you’re stressed, it’s pretty unlikely that you’re going to start developing gray hair.

[00:26:25] So you have to account for the fact that people’s hair naturally turns gray over time. Anyway, but the interesting part of this was the model includes 17 parameters. Each of which can be adjusted to simulate various effects on individual hairs in relation to the aging process, including one or two stress exposure periods with customizable, intensity and duration.

[00:26:45] David: [00:26:45] That sounds vague.

[00:26:46]Sophie: [00:26:46] It was vague. And in fact, they were quite specific about certain parts and then not so specific about other parts of the model,

[00:26:53] David: [00:26:53] For anyone who’s listening, who didn’t understand that basically they said, “and we did some stuff”

[00:26:57] Sophie: [00:26:57] Yeah, and we did some stuff and we did it in a [00:27:00] computer program. And like, this is what it tells us, but yeah, as you said, the hair needs to reach a threshold kind of stress. There needs to be a lot of things that happen before it turns gray. So it’s not just going to turn gray and stay gray. so you need to sort of be, at least middle-aged, there needs to be like A threshold and biological agent. Other factors, including stress. And then that the idea is that the stress will push it over the threshold and it will transition to gray. So yeah, the idea is if you’re 70, you’ve got old gray hair. If you get less stressed, it’s not going to turn dark again. And then if you’re 10 years old and you get super stressed, all of a sudden you’re not going to start getting gray hair, but yeah, but the interesting thing is a lot of, you know, you said there’s been some debate in the past about sort of hair turning grey.

[00:27:40] A lot of those studies were done in mice. And so the idea is showing that the hair graying is reversible and all it does is really just implicate a different mechanism, right? Like mice have very different hair, follicle biology to people and potentially that’s why the mice results don’t translate over to what we’ve seen in people’s results.

[00:27:58]David: [00:27:58] Presumably and [00:28:00] presumably like mice have hair for thermal regulation and human beings really don’t. For fashion and full looking nice and aesthetics, and now we dance. So, I mean, yeah, the hair probably exists for a different reason and we live for substantially longer than a mouse.

[00:28:15] The most only lives a couple. So it seems like a worthy reason to be splitting some hairs to me sophie.

[00:28:22] Sophie: [00:28:22] Zing but there you go, if you’re starting to get gray hairs, just relax, guys. Just relax and some of them might turn back. It’s fine.

An Audience

[00:28:38] Dave, do you think if people stopped watching me, my gray hairs would grow faster or slower.

[00:28:43]David: [00:28:43] I think it would depend on your gender, Sophie.

[00:28:46]Sophie: [00:28:46] Funnily enough. I think he might be right. Or we could be talking about something completely different Dave. So apparently this pandemic, as horrible as it has been for a load of people is telling us things about athlete performance in an interesting way. [00:29:00]

[00:29:00]David: [00:29:00] Yeah. So it’s given us an interesting opportunity to study the effect of audiences on sporting performance. so an example of this would be whether, you run faster or slower in the presence Of an audience or able to perform, uh, complex, task involving concentration, in the presence or the absence of an audience. So this is something called the,

[00:29:21] Sophie: [00:29:21] Is it the social facilitation theory?

[00:29:23] David: [00:29:23] Yes, the social facilitation theory And this is the idea that the presence or absence of an audience will change the way you perform a task.

[00:29:29] And basically so far, the theory is that anything that involves stamina, people will do better when there’s an audience and any other task, it will generally be decreased in performance.

[00:29:40] Sophie: [00:29:40] Yeah. So it’s like, if you were watching me and I was running, I would run faster. But if you were watching me and I was trying to do something intricate or something that involved a lot of concentration, like, I don’t know, knitting something real quick. I don’t know how to knit.

[00:29:51] Let’s say crochet Animal Yeah, exactly. I would be really bad at it, but it turns out that maybe there’s a difference in biological [00:30:00] sex when it comes down to this. So yes, as you said, this all has to do with social facilitation theory and there are two main categories.

[00:30:05] So there’s the activation theory. and then that claims that the presence of others yield changes in activation or arousal, ie. if you’re running fast, you’re going to run faster. And then the other category is attention theory. And so, as we said, It claims the presence of others predominantly affect individual’s attention.

[00:30:22] And you’re more likely to do a bad job if people watching you doing a task that involves that’s a concentration. and we have, Emily Heinrich, who is a sports psychology expert who coaches Germany’s junior biathlon squad. And what she actually did is so she took results. We had one event in particular, we’re talking about in 2020.

[00:30:40] So it was the 2020 biathlon world cup. And she compared by athletes’ performances in the 2020 season with, their performance in the 2018 – 2019 season when they were doing things with people watching. And she looked at two specific events, the sprint and the mass start event. So just very quickly, Dave, I learned some things about biathlons today that I [00:31:00] want to you about, so for everyone playing at home biathlons is like it’s the thing that I love watching, but it’s, I think it’s very weird. So basically you do a bunch of skiing and then you shoot things and then you do some skiing and then you shoot things.

[00:31:13] So you’ve got the sprint event, which is 10 kilometers for men, 7.5 kilometers for women, the distance is ski-ed over three laps in between the laps, you have these shootings. So the biathlete shoot twice, once prone. So prone is when you’re lying on the ground and he looked like a sniper that is the prone position of shooting in a biathlon.

[00:31:31] And then you have the standing position, where you just standing. So do one prone one standing? They do a total of 10 shots, so five in each round. And every time you miss a shot, you basically get a penalty lap of 150 meters. Well, a penalty distance of 150 meters that you have to ski before you can keep going.

[00:31:48] So the idea is a sprint event is faster. it’s sort of like a time trial, so people, they’re staggered starts for these by athletes. So that’s the sprint event. The mass start is more. It’s more like your [00:32:00] marathon. So it’s 15 kilometers and men 12.5 for women. And basically the idea is you all start at once and whoever finishes first wins, um, you don’t have a five laps and then you’ve got the four bouts of shooting to prone and two standing.

[00:32:11] And what they found were when Emily analyzed all of this data, the men’s results were as expected that the women’s weren’t. So it says that the men ran faster, but let’s say they skied faster with an audience, but performed more poorly in shooting, which is your concentration task, but it was the exact opposite for women.

[00:32:31] So they skied slower with an audience, but on average, it took them an entire second less to make their shot. And then at least in the sprint Competition, their scoring performance was 5% higher. So for the women, the results were reversed and they don’t think, or she doesn’t think it actually has to do.

[00:32:48] It’s not just a fluctuation of the athlete’s performance. There’s something potentially intrinsically different about the way men and women perform in these events.

[00:32:56]David: [00:32:56] Yeah. And there were two cool things about this. So I have two thoughts about it. one  This is [00:33:00] cool because they didn’t actually expect to see this at all. They just expected it was going to be all one way. And the only reason they put gender and their statistical model, because this was a statistical study, like based on archive data from the past.

[00:33:13]And they only included gender because obviously like people are going to be grouped by gender when they perform the sports. Like, so there’s going to be difference in lap time, et cetera. And that’s why men can be in a different category to women, et cetera, et cetera, no matter how you feel about that. so they only put gender in the model for that reason, but then they spot these differences that go in opposite directions consistently.

[00:33:32] So the resistant reaction that was beautiful. And I was a little bit skeptical to begin with because when you look at the sizes of the differences, like the sizes of the changes in say lap time, they’re quite small. But then actually when I thought about it again, these are world-class athletes where changes in milliseconds are going to be quite significant to people’s times and to the outcome of the competition. So actually I was pretty impressed by this. I thought it was a really nice study. [00:34:00]

[00:34:00]Sophie: [00:34:00] yeah, as you said, there’s a good basis for evidence. They had, a three athletes in the spring competition in 34 in the mass start and they also found that those, the same tendency for both disciplines these races that are actually performed quite differently than you by athletes who just do sprint events and by athletes who just do mass start events, you’ve got exactly the same tendencies, but then the paper raises all of these questions about, the way that we study these things anyway. So apparently it’s the first time the study was able to show a different effect of audience on men and women.

[00:34:30] And it turns out that most of the previous studies, like in a lot of things were done predominantly on men. And that actually raises questions about the generalizability of social facilitation theory anyway, so then they went back and they looked at all these old

[00:34:42] David: [00:34:42] Yeah, They did a systematic review just because

[00:34:45] Sophie: [00:34:45] Yeah, which was great. And so I love this so in 1898, some guy called triplet noted that girl seemed more positively affected by the presence of others than boys, while performing a motor coordination task. Right. Which [00:35:00] agrees with what we’re seeing here, that the women did better at these shooting things, but then apparently 120 years since then, we haven’t really been super concerned with genders. So they looked at, there was 81 publications between 1898 and 1999. And the studies represented a total of 6,144 participants. And so now we’re just talking about motor performance. We talked about the concentration ones and they found a clear selection bias.

[00:35:24] So of that 6,144 participants. 66% of those analyzed were male, 16 were female, and then 18% had no specific information. So let’s just assume male. So we’ve set up this social facilitation theory based on studying men, doing things, which we tend to do a little bit as a society, at least in the past. I think we’re a little bit more aware of it now, but yeah, it’s really interesting.

[00:35:48] So it was kind of, as you said, like a bit of an accidental discovery. Okay.

[00:35:52]David: [00:35:52] Yeah, and a really good one. It’s a nice study. so I guess if anyone at home is wondering what this means for them, if you’re going to be chased by a [00:36:00] man, do it while no one’s watching. And if you’re going to be shot at, by a woman, then try and get some people to watch,

[00:36:07] Sophie: [00:36:08] yes. Do what Dave says or don’t we don’t mind.

[00:36:12] David: [00:36:12] or don’t be chased, star shot at. That’s also fine. But if it’s got to be that way, then that’s the way you should go.

[00:36:17]Sophie: [00:36:17] Science says, so