Welcome to STEMology – Show Notes
Season 1, Episode 32
Ghostly tardigrades, wormy vulva milk, projectile crying and globe-skimming globe skimmers
In today’s episode of STEMology… Sophie & dave will discuss about
A fossilized 16 million year old tardigrades, worm’s self-destructive vulva yolk milk for its offspring, the science behind squirting milk from eyes, and the theory of dragonflies’ ability in crossing the Indian ocean
So they’ve been described as a ghost lineage for paleontologists … apparently they are like a ghost lineage for paleontologists because they have almost no fossil record
It turns out that as worm and mothers age, they secrete a milk like fluid through their vulva that is consumed by their offspring to support their offspring’s growth. So it’s a form of primitive lactation that is both selfless and sacrificial.
So faulty ducts might be the reason that people can shoot milk out of their eyes.
Dragonflies can detect and select favourable winds. Winds that propelled them up. So they, exhibit a behaviour called slope soaring, which is basically where they find thermal currents that propel them up the way. And you can show that they will preferentially find their way into that
And here’s the link to the paper that Dave refer to on the show!
This is a “kind of, sort of, vaguely close” copy of the words that David & Sophie speak in this episode.
IT IS NOT 100% accurate. We are very sorry if we have spelt something completely incorrectly. If it means a lot to you to have it corrected, email us at email@example.com
[00:00:00] David: Welcome to episode 32 of STEMology
[00:00:02] Sophie: a podcast sharing some of the interesting fun, and sometimes just patently bizarre news in science, technology, engineering, or maths.
[00:00:10] David: Your hosts are Dr. Sophie Calabretto and Dr. David Farmer. In today’s episode of STEMology we’ll be chatting about ghostly tardigrades, wormy vulva milk,
[00:00:20] Sophie: projectile crying, and globe skimming globe skimmers.
[00:00:26] David: Tardigrades
[00:00:27] Sophie: Yes, Dave, welcome to tardigrade park.
[00:00:31] David: nanny.
[00:00:34] Sophie: Thank you.
[00:00:35] David: Good. So we’ve got an incredibly ancient tardigrades and in fact it’s a new species of tardigrades
[00:00:41] Sophie: that they found in fossilized Dominican Amber, just like where they found the mosquito in Jurassic Park.
[00:00:49] David: Just like in a movie.
[00:00:51] Sophie: but they didn’t, what they haven’t done is taken its blood and made dinosaurs.
[00:00:55] David: No, they shouldn’t. Then that’s why we’re eternally disappointed with tardigrade research.
[00:00:59] Sophie: That’s [00:01:00] right.
[00:01:00] David: As cool as it is, they can withstand space. They can withstand hot springs. They can withstand the, you know, Antarctic cold, but can you make them into dinosaurs? No, you can’t
[00:01:09] Sophie: Yes. So sorry, Dave, getting back to this. Yeah, they found a new kind of tardigrade that on the outside looks like a modern tardigrade, but on the inside, it’s very, very different, but it turns out this is the third tardigrade ever to be found preserved. Is that right?
[00:01:25] David: Yeah, that’s my understanding too. So that’s not very many.
[00:01:27] Sophie: That’s not very many tardigrades at all.
[00:01:30] David: so we’ve got several, we’ve got one from this era, the cenozoik era, the geological era.
[00:01:36] Sophie: Is that one this one.
[00:01:37] David: That’s this one. So that one is 16 million years old. That’s the one that’s just been found. We’ve got two others, one from 90 million years ago and one from 72 million years ago.
[00:01:47] Sophie: Yeah. And so they’re both from the Mesozoic I learned about zoics and cene a lot this week, but it’s all sort of irrelevant, but yeah. So basically the era that we’re in now is the Miocene, which is the first geological epoch [00:02:00] of the near gene period. But basically, yeah, so this geological era is the tardigrades they’ve just found us from that. And then the other ones were quite old, but it’s got something to do with the fact that like, they just don’t preserve well, isn’t it?
[00:02:12] David: Yeah. So apparently they don’t contain the sorts of minerals that would result in fossilization but they also point out that it’s also just difficult for them to die. So maybe they don’t fossilize that. Well, because not that many of them actually die.
[00:02:26] Sophie: Most of them run out of the Amber as it’s setting. They’re just like, I will not be held by you. And they just like forced their way out of the Amber. That’s what I’m guessing.
[00:02:35] David: Yeah. So they’ve been described as a ghost lineage for paleontologists. So though we know that they’re really, really hardy and although, we know that they’ve been around for millions and millions of years predating the dinosaurs or being contemporary with the dinosaurs. Anyway, apparently they are like a ghost lineage for paleontologists because they have almost no fossil record.
[00:02:52] Sophie: Yeah, which is crazy. And so this is like quite a big discovery. And also the fact that this particular tardigrade, as we said, has a [00:03:00] very unique foregut organization, which is why they know that it’s different to the modern tardigrade and the reason. And I thought this is kind of cool. So it’s basically like they found this tardigrade
[00:03:10] preserved in our Dominican Amber. it is very, very small. So just over half a millimeter in length and basically too small to look at properly with just a normal dissecting microscopes. So they use confocal microscopy, which I hadn’t heard of, but it’s quite, it’s sort of like simple, but also quite clever.
[00:03:26] So the whole idea is that you sort of use lasers and lenses to focus light on a certain plane, and then you have like the light reflecting and then there’s this pinhole which only accepts the InFocus light from that plane. So you can kind of look at the sort of different plane sections, of this tardigrade and then that’s how they saw inside.
[00:03:44] They saw that I think the claws were like slightly different, but it was mainly the mouth apparatus or the foregut, which was quite different insight. And then that’s how they know that it’s a different kind. So basically tardigrades have evolved Dave.
[00:03:58] David: Yes. And so this is one of the things I [00:04:00] find most amazing about this study. So as you say, they looked at the foregut gut and they could see from the foregut that this was a new type of tardigrade one they hadn’t seen before by the forego organization, but they could see this creature’s mouth parts and its claws.
[00:04:11] So you’re talking about micron level detailed, but you’re talking about micron level details on a fossil that 16, million years old.
[00:04:21] Sophie: Yeah. That’s not nothing like, that’s pretty impressive that even that sentence. Yeah.
[00:04:25] David: so yeah, we use confocal microscopy. I’m glad you explained confocal microscopy, because I’ve used confocal microscopes. I didn’t understand how they work.
[00:04:32] Sophie: Well, I mean, I didn’t explain them that, well, I’ve got a picture in my head that I wanted to learn a thing. And then there’s one thing and another thing, but yeah, basically it’s just using in focus and out of focus light to pinpoint certain things that you want to look at. But yeah, in the plane I just say it was a very clever, so you can kind of get this nice
[00:04:46] section really of the tardigrade inside though. That’s the cool bit you can look inside. It’s not just kind of like we see a shape in the Amber. Yeah.
[00:04:54] David: I got interested. See, you mentioned the tardigrades have evolved. I got interested in that because I got interested in the fact [00:05:00] that, so if we don’t have that many fossils of them, how do we know that the species is that old? so you’ve got these two examples of one from 19 million years ago and one from 72 million years ago.
[00:05:11] But apparently you can also date organisms using something called the molecular clock, has been used to date tardigrade as a species. and apparently this involves what it involves is looking at the mutation rate of bio-molecules. So what I mean by that is you look at things like usually nucleotide sequences in DNA.
[00:05:29] Or amino acid sequences in proteins. And because you can look at different organisms through time and look at the rates at which the molecules have become different, you can work out the mutation rates of molecules
[00:05:41] Sophie: Oh,
[00:05:42] David: which means you can look at a contemporary organism and based on what its molecule looks like kind of infer, how mutated it is.
[00:05:49] And therefore at what time in the, you know, its evolutionary past it diverged from another species.
[00:05:56] Sophie: So you can basically backdated.
[00:05:57] David: Yeah, you can backdate to just by looking [00:06:00] at how it works now, which is kind of amazing as well.
[00:06:03] Sophie: That is very cool, but yeah, I like this and I also just got excited about Amber and dinosaurs, Dave, but, um, I’m going to talk about Amber and dinosaurs because Jurassic park is not a documentary as much as I want it to be this particular piece of Amber that they found also contained partial flowers and some beetles and three ant workers.
[00:06:20] David: that’s lovely.
[00:06:21] Sophie: How cute is that? It’s just like a little menagerie in the
[00:06:23] David: Snapshot of life is lovely. and the researchers hope that the discovery might inspire others to take a closer look at Amber samples in the hope of finding out more about these animals. and apparently I didn’t realize this, but we’re just scratching the surface when it comes to understanding living tardigrade communities.
[00:06:39] Especially, I didn’t realize this in places like the Caribbean, where they’ve not been surveyed and are presumably really chilled out by comparison.
[00:06:46] Sophie: Yeah, I would, I think so. I think they just like lying on beaches you know, that’s how they got caught in the amber
[00:06:51] David: just
[00:06:52] Sophie: SAP, because they were just chilling. And then this ant, like the sap just like started oozing on them and they were just like, oh, just see how it goes. And then, uh, and then it was [00:07:00] too late. It’s too late for them to get out.
[00:07:02] David: she’ll be right.
[00:07:03] Sophie: But then there was one other thing that I want to talk about very quickly, Dave. And it’s this idea of like also fluorescence? Did you look at the cool glowing tardigrade in the paper?
[00:07:11] David: Yes. So it glows. so one of the things with confocal microscopy is that you don’t illuminate so with a normal microscope, you illuminate the whole sample, right? You just shine as much light everywhere as you can. And with confocal microscopy, you don’t do that. You only eliminate the piece of tissue that you’re looking at.
[00:07:27] and you can do that with basically any wavelength of light that you like. So if you turns out with the tardigrade, if you pick the right wavelength of light to shine on the tardigrade, it actually glows in the dark.
[00:07:38] Sophie: Yeah. And so, and this is really funny, cause yeah, so the autofluorescence has just they emit natural emission of light from like biological structures. But when I was looking into it, it turns out that, so for this particular work, it was quite useful because you could use like the different colors to highlight the different tissues.
[00:07:53] But often, like most of the things I found on the internet about autofluorescence is how to stop it. And people are just like, it’s getting in the way of it. [00:08:00] So I really, like, I thought they used autoflouresence for good in this
[00:08:03] particular case and then made this like very cool glowy image of a tardigrade, which I
[00:08:08] David: That’s right. so often biologists will use fluorescent molecules to study particular things of interest. So if you’re interested in say immune cells, you might pick a gene that the immune cells have and then cause it to be fluorescent using genetics. And therefore you want to look at that fluorescence. So if there’s something autofluorescence, then it’s just going to get in the way of looking at the beautiful immune cells, gone to lots of trouble to staying up.
[00:08:30] But yeah, you’re absolutely right. They were just like, oh, cool. It also fluoresces. We don’t even need to do anything
[00:08:35] Sophie: This is very helpful, but yes, there you go. And we’re one step closer to understanding our little microscopic Caribbean friends,
Wormy vulva milk
[00:08:42] Sophie: Dave
[00:08:54] self-destructing worm, vulva, yolk milk.
[00:08:58] David: these are words that I have [00:09:00] not put in this particular order before Sophie.
[00:09:02] Sophie: No. And so this is from our friend, uh, our little, roundworm friends, C elegans. So if they, everyone playing at home, remember if you crush up C elegans and eat C elegans, you can learn everything they know. and so, yeah, basically there’s a thing that happens to these. These are one millimeter long, transparent roundworms.
[00:09:20] they get to an age and they basically, uh, liquify their insides and, Look, I just want to preface it with this thing we’re about to describe, scientists previously assumed that these changes that happen in the worm were futile and represented some form of old age disease state, which just seems very like a bit condescending.
[00:09:40] It’s like those worms have no idea what they’re doing, but in
[00:09:43] David: Look at them, lactating, their pus-filled organs and them, what idiots.
[00:09:48] Sophie: idiots, but it turns out that as worm and mothers age, they secrete a milk like fluid through their vulva that is consumed by their offspring to support their offspring’s growth. So it’s [00:10:00] a form of primitive lactation that is both selfless and sacrificial. Dave.
[00:10:04] David: Yeah. So to be clear, they generate this yolk inside their body, forms these large pills and save their body and consumes their internal organs. So they’re actually breaking themselves down.
[00:10:14] Sophie: Yeah, they’re basically converting their biomass into milk.
[00:10:19] David: Yes. And so this is the first study where they’ve shown that it’s produced and that it’s expelled for the vulva. And also that it’s eaten by the larvae and that the larvae that eat it benefit from it. And they did this in a really clever way. In fact, we were just talking about making things fluorescent, right.
[00:10:38] So what they did was they took C elegans and they made it transgenic, which is to say they changed its genetics artificially. And what they did was They tagged a particular protein with a fluorescent protein and the protein they tagged was called Vitellogenins yolk protein.
[00:10:55] So whenever these worms make Vitellogenins yolk protein, it glows [00:11:00] basically. And what they showed was that if you had worms, a female worms of a particular age on a dish, they would glow. And also they would expel fluid that glows .
[00:11:08] Sophie: yep.
[00:11:09] David: Which is disgusting and scientifically great.
[00:11:12] Sophie: There’s a video, please check out the show notes for supplementary video number one. It is gross.
[00:11:17] David: and then more excitingly they were able to show that baby worms in the same way would’ve consume it. So basically they had worms of a certain age on the dish. They would expel this gross yolk stuff, and then they took those worms off, put some larvae on and showed that two things. One that after some time, some of the larvae would glow showing that they had ingested this glowing protein and two that the worms that did seemed to do a bit better in terms of their growth.
[00:11:43] Sophie: Yeah. They’d had their wheat bix, right? Like a, so, so I love this idea. So basically what happens is this makes me really sad though. So you’ll have C elegans. And as I’ve said, we’ve got male and reproductive organs. Basically what happens is they reproduce using limited stocks of self sperm.
[00:11:58] And then when they run out of self sperm, [00:12:00] which is within days of sexual maturity, so they don’t live a very long time reproduction ceases, and then that’s when you get this process happening. And so what they used to previously do was just like, I mean, they still do it. They would lay their own body weight in unfertilized eggs and these scientists, which is like, well, that’s a dumb thing to do, or they’re very confused and old, but it turns out it’s the eggs that are full of this gro ss yolk milk. so they’re basically making little milk bottles, but the little milk eggs for then the larvae to eat, as you said. And yeah, the ones that do basically grow up big and strong compared to the ones that don’t.
[00:12:35] David: Well but at what cost.
[00:12:40] Sophie: but yeah, so basically it’s just this way of like, transferring resources to their offspring in a really, really gross way. And then as I said, I like to end up in the supplementary material cause I I’m going to be honest Dave. Cause I’d never seen a worm vulva over before and I was just intrigued it’s on the side of their body by the way.
[00:12:58] and yeah so there’s a.[00:13:00] to go with the line in the paper, yolk was vented through the vulva in brief bursts, either alone or with unfertilized. Now I never say this word, Dave right, oocyte..
[00:13:10] David: Yeah.
[00:13:10] Sophie: oocyte or just ooze
[00:13:12] David: Uh, Ooh,
[00:13:13] dates. I think you said you make two signs oocyte.
[00:13:16] Sophie: Yeah. So I was like, oh, I’m intrigued as to what this means yolk was vented through the vulva brief bursts, either alone or with unfertilized oocytes. And then there was a link to the supplementary video and you literally see the glowing milk, like being puffed out in bursts from a tiny one vulva.
[00:13:33] David: Oh, it’s just not very good. Is
[00:13:35] Sophie: it?
[00:13:35] It’s just something I never thought I’d have to do for science.
[00:13:38] David: Yeah. And presumably these scientists feel the same. And the reason they’re doing this is because, because these worms do this when they’re about to die. If it turns out that there’s a pretty, relatively simple genetic trigger for this behavior to happen.
[00:13:52] And in worms, if you prevent this genetic trigger from happening, then they don’t die. They just extend their lives up to about 10 [00:14:00] times. So. These researchers are interested in this, not just because it’s gross and evocative, you know, depositing, glowing yolk eggs from one’s vulva, but because maybe it can tell us something about aging and other species, including maybe ourselves, because what happens to us?
[00:14:16] I don’t know if you know this Sophie, but we get old and then we die.
[00:14:19] Sophie: Yeah, I’m definitely getting old.
[00:14:21] David: yeah, I feel like I’m getting old. I mean, not expelling vulva milk through my vulva, but
[00:14:27] Sophie: Well, me neither, Dave, that makes you feel
[00:14:29] David: I’m glad to hear that.
[00:14:31] Sophie: yeah. And good. But then I think there was, like sort of some caveats that Dave that didn’t quite understand that thought. Maybe you could explain to me, but they said that if this life extension of C elegans is just to suppression of suicidal reproduction, like in salmon.
[00:14:44] So, you know, you’ve got when salmon reproduce, they kill themselves in the process then basically, it’s not going to help us understand aging, but if that’s not the case and it will.
[00:14:52] David: Yeah, so, the way I understand that is, so I’m not an expert in aging. Let me just preface everything. I’m about to say by saying that, but [00:15:00] basically if you think of aging, aging happens for a variety of reasons. You know, your telemeters get shorter, your stem cells get exhausted metabolic because there’s a thing called metabolic exhaustion, where basically you’ve been exposed to oxygen for so long that your cells just can’t cope anymore.
[00:15:16] Sophie: I know the feeling.
[00:15:17] David: Fall to bits. so I guess the question is so let’s say C elegans lives for a few days. And if you prevent this genetic thing from happening, they live 10 times that the question is, is the initial period, the typical end of their life, and we’re then extending it, or is the 10 times
[00:15:36] length the typical extent of their life. And that’s being limited by this reproductive process. So if they live for 10 times the usual time that they live and that’s being limited by stem cell exhaustion and metabolic exhaustion and all these other things, then it doesn’t really help us because presumably the same things are limiting our own lifespans because we don’t have this reproductive trigger.
[00:15:59] When you have a baby, [00:16:00] you don’t suddenly fall to bits. Create a bunch of milk. I
[00:16:04] Sophie: can you imagine, I just feel like that would be a great horror movie. David, I’m going to need to talk to you after.
[00:16:08] David: I feel like our society would be structured in a different way if that’s what happen.
[00:16:12] Sophie: Yeah, just in a disturbing way, but yeah, I thought that was, disgusting. It was interesting. There were great pictures and yeah, C elegans just continuously coming through with the goods,
[00:16:22] David: and glowing.
[00:16:23] Sophie: glowing, disgusting goods. Thank you. C elegans,
[00:16:26] Sophie: Dave, I’ve got a question for you.
[00:16:38] David: Yes, Sophie,
[00:16:39] Sophie: Why can some people squirt milk from their eyes whilst others can’t?
[00:16:44] David: I don’t know. Prior to reading this story, I didn’t know that this was a thing.
[00:16:48] Sophie: Oh, whereas I did, because I think, I know we mentioned this when we were picking the story. So there was a, so everyone’s aware of the Guinness book of world records and there was for a period of time. And I want to say like, in the early [00:17:00] two thousands, I think there was a TV show where people. The records that were very, um, performative.
[00:17:07] They would basically people on TV on this TV show, which will never be produced. It wasn’t live would try and compete for certain, world records. And one of them I remember seeing was a man shooting milk out of his eye at a very, like a very far distance. And he got the world record for the Guinness world record.
[00:17:24] That’s not pretended to wherever.
[00:17:26] David: I was about to say what a champion, but I mean kind of facetiously, but he is literally a champion.
[00:17:31] Sophie: He’s
[00:17:31] David: is a
[00:17:31] Sophie: a champion.
[00:17:32] Yeah. So his name is, I did look it up for everyone at home. So his name’s Ilker Yilmaz he’s from Turkey. And on the 1st of September, 2004, he squirted milk from his eye, a distance of 279.5 centimeters. So 2.79 meters, he could squirt milk. Out of his eye and it, turns out, so what we had here was it wasn’t really a paper.
[00:17:52] It was a, a case report with three cases with some conjectures and they think Dave that, people who [00:18:00] can kind of push air or liquid the other way, which we’ll talk about in a second, possibly have abnormal valves. The idea is, this is what we’re about to describe is like a sewage system for your eyes.
[00:18:11] And it drains all the crap out of your eyes, into the back of your nose and throat. And these people can just do it in the opposite direction.
[00:18:17] David: So I didn’t realize this right. I’m a biologist and I did not realize this. So first of all, You’ve got something that I did realize you’ve got lacrimal glands that produce tears, and then there’s a duct that drains the tears into your eyes. Fine. Right. I thought that’s what tear ducts did. I thought they deposited tears.
[00:18:34] Sophie: Yeah. I thought there were the ducts that teared, as opposed to ducts that take the tears away.
[00:18:39] David: Yeah. So you’ve got those and then you’ve got another set of lacrimal ducts that drain to something called the lacrimal sack and that deposits itself in the back of your nose and throat, which is why when you cry a lot, if anyone’s ever cried a lot is presumably most of us have you get a runny nose because the tears drained from your eyes, not just on your face, but also [00:19:00] into the corner of your eyes, nearest your nose, and then go into the sink with the lacrimal sack, and then go back down in the back of your nose and come out of your nose.
[00:19:07] And that’s why you get a runny nose.
[00:19:09] Sophie: So tear ducts, like, as we know them are actually the nasal lacrimal ducts and you’re right though. So they attached to everything. They actually drain the stuff away. And as you said, that’s why you, when you cry, you get like a runny nose because it’s your tears moisturizing everything in your face.
[00:19:22] and then pace, it could look along the trip, you know, so let’s say I’ve cried and now my tears are draining into my nose and throat along the way in me. I have valves that stop the flow in the other direction whereas there are some people who can basically it’s, it’s all got to do with pressure by the looks of it, but they can force air or liquid the other way from their nose through to their eye holes.
[00:19:48] David: Yes. And so the way they do that is by doing something called the maneuver of Valsalva.
[00:19:54] And this is something that everyone has done, because this is the maneuver you do when [00:20:00] you are trying to poop.
[00:20:01] Sophie: Yeah. Also when you’re, I think I remember you saying, I was like, oh, I looked up. I was like, oh, it’s also like, if you’re in an airplane and try unblock your ears.
[00:20:08] David: Yeah. So you can do it by, with, or without, blocking your nose. So if you do it again, if you just close your throat, like you usually do when you’re, I don’t know how you poop or
[00:20:17] Sophie: I
[00:20:17] know. Next time I
[00:20:19] to the bathroom
[00:20:19] David: people don’t
[00:20:20] hold their noses while they’re doing it, or if they do or holding their noses for a different
[00:20:23] Sophie: but I’m really gonna monitor everything next time I go into the toilet
[00:20:27] David: Ok. I expect full report.
[00:20:29] Sophie: okay. I’ll report back on stem ology next week.
[00:20:31] can you
[00:20:32] David: all looking forward to that.
[00:20:33] Sophie: so yes, Dave, tell me about pooping
[00:20:36] David: So you perform the maneuver of Valsava. So this is when you block your nose and you exert a pressure as though you’re trying to blow out, but because you’re blowing out against the closed nose, you build up the pressure in your chest and the back of your throat and your mouth. so you’re generating a pressure and that lack rumble sack, which then, because these people maybe have weird valves, enables air to escape from the tear duct
[00:20:58] where it usually [00:21:00] drains.
[00:21:00] Sophie: exactly.
[00:21:01] David: Sometimes Sophie, sometimes Sophie producing a high pitched sound. And presumably when they say it produces a high pitch sound, they mean in addition to the high pitch sound of,
[00:21:14] Sophie: Oh, just the guy I was like in my head at some mosquito. It’s like having one whiskey. Um, yeah, so this,
[00:21:21] David: well like a tiny flapping sound. Yeah.
[00:21:26] Sophie: yeah, but yeah, so this particular case study, they really only looked at three people. So we have a 35 year old patient presented with complaint of tear duct expansion.
[00:21:36] David: was wrong with this person? He didn’t even say, oh, my tear, duct expands. What seems to be the trouble, sir? Tear duckts expand,, like not my tear ducts. Now I seem to be having a problem with my eyes. Just tear ducts expand.
[00:21:49] Sophie: a tear, duct expanded I’m seeking advice. and yeah so they did a CT scan and it revealed that his right lacramal sact was distended by air. And they hypothesized [00:22:00] that it was a dysfunction of the valve of hasner, which I realized I now didn’t look off and that name makes me giggle a bit and I regret it.
[00:22:07] and then we had a 42 year old patient and his son, a 9 year old patient. And they are the people who presented with a sensation of any of the ocular region, but also that high pitched sound, which I wish there was a recording of, I want it like, could we all hear it or could they only hear it, Dave? That’s my question
[00:22:21] David: Yeah. Or did you need specialist equipment? That’s what I want to know.
[00:22:24] Sophie: Yeah. And they’ve, hypothesized that, they’ve got compromised valve function along the entire lacramal excretory system beginning when the valve of hasner, but also including the valves within the duct, which other valve of Rossenmuller and the Punctal valves
[00:22:39] David: So these are valves that presumably were found during the sections of cadavers by
[00:22:43] Sophie: by German, man.
[00:22:44] David: Various mostly German people.
[00:22:46] Sophie: Yeah. Apparently.
[00:22:47] David: I’d say it’s amazing that like you would think that someone who found one would find them all, but no, it took three different forays into the lacramal ducts to spot all these different valves.
[00:22:58] Sophie: Maybe they were all in the room at the [00:23:00] same time. divided them up
[00:23:01] David: maybe they did that’s
[00:23:02] Sophie: and you can have that one. You can have that one, but I like how one of them is one or they’re all like that. It’s not just like the Hasner valve or the Rosenmuller valve. It’s the valve of Hasner I think that’s it’s a more dramatic name.
[00:23:13] Isn’t it. But then like Punctal valve, that just sounds like very,
[00:23:16] David: Well, it’s a bit descriptive. Isn’t it
[00:23:18] Sophie: It’s a bit descriptive, but so I’m just, I’m going to digress slightly because it’s what we love to do here on STEMology. . So when I was looking up my piece of information about my Turkish man, who shoots milk through his eyes in world record distances, I stumbled across another Guinness world record that had to do with shooting milk out of your eye.
[00:23:35] And this one was from 2013. And we have, Brandon “Young blood” Kee, who now has the world record for the fastest time to ignite five target with milks squirted from the eye..
[00:23:45] David: to ignite.
[00:23:47] Sophie: I watched the video and it’s exactly what I said. So it’s this guy who, and it’s amazing to watch because apparently Ilker our Turkish friend.
[00:23:55] He would get the milk into his eyes by basically he’d put milk in his [00:24:00] hand and kind of suck it up through his nose. Whereas Brandon just used a glass of milk and kind of drunk it into his nose. And then they had a table set up that had, I shit you not five martini glasses. And there was something at the bottom of each of them.
[00:24:14] And I couldn’t like, there was no information as to what it was, but it has to be like some kind of potassium thing. Right. Cause you think, you know, like think of, did you have to do that experiment at school where you throw a hunk of potassium into the
[00:24:23] David: and men and it skates around
[00:24:25] Sophie: Yeah. And it like fires. It was kind of like that.
[00:24:27] So surely it’s something that is like ignited through liquid, but basically he’s there. And so he’s like, like from a distance, these martini glasses just like shooting milk, so that was all about accuracy. So it shoots milk into martini glasses. this little flame that like glows up and then he goes on to the next one and he has to do at one stage, he has to reload cause he runs out of eye milk, but.
[00:24:46] So the previous world record was like a minute something, this guy in 34.9 seconds shoots milk at a distance to ignite five different martini glasses full [00:25:00] of, I think potassium something. it was weird, Dave,
[00:25:03] David: I just don’t. I’m I’m speechless.
[00:25:07] Sophie: Anyway, but yeah, so, uh, it turns out that if you or anyone, you know, can shoot disgusting things out of your eyes, you probably have faulty valves. And, I do like, and I didn’t write down direct quote, but in this particular case study, they said that they were basically, they were just going to monitor, like, it was like kind of like surgical intervention was not decided like it was necessary.
[00:25:27] It’s like, what are you doing? It’s fine.
[00:25:30] David: I know. Yeah. I feel like if it was necessary, that would be a good way to stop people from doing it.
[00:25:35] Sophie: Yeah, but apparently it’s not even Like that whole system is like very well thought out by, I dunno God, whoever invents right here on stem ology. but yeah, so they, they decided that this particular issues that these three people had probably didn’t need surgical intervention, which is good.
[00:25:49] Cause I just think cutting anything near your eyes is not a good idea.
[00:25:53] David: no. And it just seems like a bit much, like I could shoot milk from my eyes. So under the knife I went, I mean, it feels like something very innocuous, but [00:26:00] something very serious
[00:26:00] Sophie: Yeah, we just cut something off, but yeah, there you go. So faulty ducts might be the reason that people can shoot milk out of their eyes.
[00:26:07] David: Faulty ducts.
Globe-skimming, Globe skimmer
[00:26:08] David: Sophie can dragonflies migrate thousands of miles across the Indiana.
[00:26:24] Sophie: Theoretically. Yes.
[00:26:26] David: Theoretically. Yes. Hypothetically. Yes, we think so. It’s feasible maybe.
[00:26:32] Sophie: Yeah. And I like that. This is all based on, so apparently Marine biologists, Charles Anderson in 2009, put forward this question, Dave, after observing Globes skimmer dragonflies, the, uh, old mates Pantala Flavescens
[00:26:45] David: Old mate.
[00:26:46] Sophie: yeah, in the, uh, in the Maldvies um, that had flown in from what he assumed was India. And then when they flew off again, it was towards east Africa and he went, can they migrate thousands of kilometers and then turns out we wanted to know, but [00:27:00] we had to do it theoretically, Dave, because these dragonflies are too small to have transmitters put on them.
[00:27:04] So if you them on, I liked that. It’s like we put the transmitters on them. They wouldn’t be able to fly. We need to
[00:27:10] David: I, I like the idea that they tried it, that they put a transmitter on this dragon fly and it just like fell out of the sky
[00:27:16] Sophie: Yeah, and they went, oh, okay. Can we make a smaller transmitter? And no, we’re gonna have to do this a different way.
[00:27:22] David: So the question is, and it’s quite a big question is can a dragon fly that weighs 300 milligrams, which is not very much, cross 2000 kilometers of open sea, which is quite a lot
[00:27:33] Sophie: Which is quite a lot. And it turns out that their flight speed is up to five meters per second day, which like fast for a dragon fly. But like not fast, if you think of like the distances that sort of need to be traveled and how long that will take.
[00:27:45] David: Yeah. And so if, they can, then the globe skimmer dragonfly migration across the Indian ocean would be the longest in the animal kingdom in relation to its size.
[00:27:53] Sophie: Like it’s huge. I can’t do anything. However long, we just said 2000 kilometers. I
[00:27:57] David: Hypothetically, theoretically, probably.[00:28:00]
[00:28:00] Sophie: Probably I can’t. guess.
[00:28:02] David: so basically they did two things. One was, they looked at the physiological aspects of the organism, which is to say, they looked at the amount of power that it consumes when it flies and how much fat in energy it stores in its body and said with the amount of energy stored in the dragonfly’s body with the amount of energy it uses per unit time, could it theoretically get across the ocean of its own volition?
[00:28:26] And the answer was. Yes, but only if it did it at the shortest possible crossing time with the greatest possible efficiency. So they were like, that seems unlikely. So it must also depend on the wind.
[00:28:39] Sophie: Yeah. And I thought this was really interesting. So just looking at the energetic flight model for this particular dragon fly, they said, yeah, a hundred percent, there has to be a mixed strategy of gliding and active flapping. And then the gliding is going to obviously depend on the wind, which we can talk about in a sec.
[00:28:53] because, so if you do gliding and active flapping, and so that’s a shaming that the metabolic rate of gliding is close to resting. So you just stuck your arms [00:29:00] out and you just like just hanging out. You’re not doing anything but they can stay airborne for up to 230 to 286 hours, that’d be able to stay airborne if they were using a mixed strategy of gliding and active flapping.
[00:29:12] But if they just did continuous active flapping, that reduces to four hours, like that’s a huge difference Dave.
[00:29:19] David: Yes. and I read, so they have a power output of 0.1, nine Watts. I went looking that to put it in perspective is a bit less than half of a 55 inch television on standby.
[00:29:30] Sophie: Okay. 55
[00:29:31] David: So not very much.
[00:29:33] Sophie: not very much at all.
[00:29:34] David: so basically, yeah, you’re right. So their flight time will be greatly shortened. So they’ve say that basically two things have to be true.
[00:29:41] If they have to use a mixture of flying and gliding, they have to have favorable winds. And it also said something that really caught my attention, which is that they would have to have good wind selection ability. Yeah. So I look, I was like, what the hell is that? So I went and looked and apparently [00:30:00] dragonflies are able to detect and select favorable winds.
[00:30:04] So there’s a paper which we’ll put in the show notes, which shows that dragon flies can detect and select favorable winds. Winds that propelled them up. So they, exhibit a behavior called slope soaring, which is basically where they find thermal currents that propel them up the way. And you can show that they will preferentially find their way into that. There’s also other instincts. So there’s an there’s something called entomological radar, which is the scientific technique for detecting insects. And they showed that kind of migratory moth would actively select high altitude fast-moving Airstreams that would go in a direction that was beneficial for their autumn migration.
[00:30:42] Sophie: Yeah.
[00:30:43] David: yeah. So not only are these organisms just, they’re not just flying into the wind and happening to end up there. There’s actually some active selection of they know where they want to go and they’re able to maximize it. So they’ll actually come and they’ll exhibit they’ll orient themselves in the downwind [00:31:00] direction.
[00:31:00] And they’ll also find that when the wind is going in the wrong direction, they’ll actually use as much of it as they can. So they’ll compensate for the crosswind, like a plane landing in the So that they’re maximizing the direction that they want to go in. So these guys. Yeah, they’re not just going into the air and ending up in Africa.
[00:31:16] They’re actively selecting where they want to go and then flying there and picking the winds to get in there with the greatest efficiency, which I think is bloody amazing. Cause they’re insects.
[00:31:24] Sophie: It is. Yeah. And so this are the according to the simulated migration experiments using the wind models. So 15.2% of the dragonflies could manage the migration from India to Africa in the autumn. And that would take approximately 127 hours. And then in the spring 40.9 could make the same journey in the opposite direction.
[00:31:43] And that would take about 55 hours. that was yeah, taking all these things to encap. That’s crazy that they can just, they do that instinct insect inst inct.
[00:31:51] David: That’s bloody amazing, bloody amazing animals.
[00:31:53] Sophie: But yeah, and they make an interesting point though, Dave, that there’s a lot of other, well, not a lot of, but there are other animals that rely on [00:32:00] favorable wind conditions when they migrate such as the Amer the ammo Falcon and the Jacobin cooker, they also fly across the Indian ocean, but they make a good point that, climate change
[00:32:12] may affect the chance of these things to actually migrate because when the ocean surfaces get warmer, the associated wind patterns are going to change.
[00:32:20] So there’s this thing where like, we just keep messing everything up with climate like, when you think about climate change, you wouldn’t go like, well, climate change, that’s going to stop all these things from being able to migrate and do what they need to do.
[00:32:29] But like, so this is what things are going to look into, like a little bit more from my understanding, but then the other thing I want to talk about, David’s just names. Cause you know, we get into names sometimes. This, so this particular dragon fly just has some great names in different languages. So in English, the common names are the wandering glider and the globe skimmer.
[00:32:47] And that literally refers to the migratory behavior that we’ve been discussing. In German, it’s called the Wandelibber I don’t know if that’s, I can’t speak German. That means migrant dragon fly. So they called up migrant dragonfly. [00:33:00] In Hong Kong. It’s name translates as typhoon dragon fly as it arrives with or shortly before the seasonal rain.
[00:33:07] And then the Japanese name is again, apologized for pronounciation of everything is also Usubakitombo,which translates to yellow dragon fly with delicate wings. Which is just beautiful. So that’s just like more of an evocative name and then the best one So the south Korean name is Doen Jang dragon fly because its color is similar to Doen jang, the Korean bean paste.
[00:33:28] David: Oh, there you go. That’s altogether more earthy. Isn’t it?
[00:33:31] Sophie: Yeah. So I just like that, like the different languages, how they go about naming these things. So it’s kind of like, you know, German and English, just like very straightforward.
[00:33:39] David: compounds noun, and here you go. Bam.
[00:33:42] Sophie: Yeah. And then we have, you know, it’s a slightly more descriptive names in the Asian languages.
[00:33:46] David: Love it.
[00:33:48] Sophie: that was a wee bit of a digression. I apologize, but you
[00:33:50] David: No, I love the digression. So not only is it an amazing example. So what we’ve established is that we haven’t actually observed a dragon [00:34:00] fly, crossed Indian ocean, it is theoretically possible, even probable based on both the weather and the physiology of these dragonflies
[00:34:10] Sophie: And then also the fact that they seem to be in these different places and they go, via the, uh, the Maldives
[00:34:15] David: Yeah. I wonder if you could do something, that’s not put a tracker on them. Couldn’t you just paint them or something?
[00:34:22] Sophie: interesting yeah. Just like paint them different colors. What are, yeah. just tag them, micro tags.,
[00:34:26] David: scientists, when they talk about other scientific fields, sometimes have a bad habit of saying, why don’t you just, and then describe 10 years of work. and I feel like that’s what I might be doing now, but, um,
[00:34:37] Sophie: another idea, Dave, why don’t you just follow them? Just little aircraft, just like pick one, just follow it. See where it goes.
[00:34:43] David: Just to strap some delicate wings on. Little disguise. So you blend in.
[00:34:48] Sophie: Some delicate wings
[00:34:50] David: Get yourself, a bean paste body suit.
[00:34:53] Sophie: true.
[00:34:54] David: And off you go you’re, you’re one of them. And you make you infiltrate the bean curd, dragon fly [00:35:00] community, and just follow them across the little ocean
[00:35:03] Sophie: And who knows, they might really like you and adopt you as their overlord. So, you know, there’s that as well,