Speaker 1: Hey, they're extraordinaries. Kelly.
Speaker 2: Here my book, A City on Mars? Can we settle Space?
Speaker 2: Should we settle space? And have we really thought this through?
Speaker 2: Comes out in paperback on July twenty ninth, So if
Speaker 2: you've been interested in reading it but the hardback version
Speaker 2: was just too expensive or the wait list at your
Speaker 2: library was intolerably long, then you're in luck. In this
Speaker 2: book we answer questions like where are we likely to
Speaker 2: settle in space? Can we make babies in space? Why
Speaker 2: do astronauts love taco sauce? And what's the legal status
Speaker 2: of space cannibalism? So grab yourself a copy of A
Speaker 2: City on Mars wherever fine books are sold. Conflicting advice
Speaker 2: is making me twitch?
Speaker 1: Is it good or is it bad? To scratch my itch?
Speaker 3: If the ort cloud is filled with icy rocks? Why
Speaker 3: isn't our view of the stars blocked?
Speaker 2: Are honeybees Nature's mathematicians? Or can nature forge hexagons without cognition?
Speaker 3: Whatever questions keep you up at night, Daniel and Kelly's
Speaker 3: answers will make it right.
Speaker 1: Welcome to Daniel and Kelly's Extraordinary Universe.
Speaker 3: Hi, I'm Daniel, I'm a particle physicist and I love
Speaker 3: hearing questions from the public. What people are wondering about,
Speaker 3: what they're curious about, what they are confused about. Right
Speaker 3: to be please and share with me your confusion.
Speaker 4: Hello.
Speaker 1: I'm Kelly Winer Smith.
Speaker 2: I study parasites and space, and I totally agree with Daniel.
Speaker 2: And also I have to note that these questions have
Speaker 2: pointed out to me how many things I don't think
Speaker 2: hard enough about. Like today we have some very basic
Speaker 2: questions about like why do we itch? And I you know,
Speaker 2: I must scratch ten or so times and like, yeah,
Speaker 2: maybe even more without thinking about it. And I've never
Speaker 2: really thought about why. And so I am loving the
Speaker 2: opportunity to dig into all of these different questions.
Speaker 3: Yeah, it's fun on so many levels, Like we get
Speaker 3: an opportunity to learn more about areas that we've always
Speaker 3: been curious about but never had an excuse to dig into,
Speaker 3: Like yeah, when have you told yourself I have an
Speaker 3: hour free, I'm a to read about itching? But now
Speaker 3: you have a reason, right, Yep. You also discover how
Speaker 3: many basic things in science we're still pretty clueless about,
Speaker 3: you know, like how many things we understand at really
Speaker 3: just the surface level. Yeah, which means that there's lots
Speaker 3: of things to figure out for all you young scientists
Speaker 3: out there.
Speaker 2: Yeah, that's right, all the kids who are listening, there's
Speaker 2: a lot of work for you to do, and just
Speaker 2: keep a list as we go through these episodes of
Speaker 2: questions that need answers that you might be the one
Speaker 2: to answer.
Speaker 3: That's right. The forefront of human knowledge is not that
Speaker 3: far away from where you are right now in lots
Speaker 3: of cases. I mean, yeah, we've been doing physics for
Speaker 3: a long time and we've made some progress, and it
Speaker 3: takes a while to understand all the details of particle physics,
Speaker 3: but they're still very basic questions even about particle physics,
Speaker 3: that we don't know the answers to. Why are there
Speaker 3: so many particles? What do they all do? What is
Speaker 3: the rest of the universe made out of? You know,
Speaker 3: basic stuff everybody wants to understand. And so if you
Speaker 3: have a question about the universe or parasites or parasites
Speaker 3: in the universe, you might be asking a question right
Speaker 3: at the forefront of our knowledge. So don't be shy, ask.
Speaker 2: Away and let us do the research for you. So
Speaker 2: I have an answer I'm just itching to share with you.
Speaker 2: We got we got there must have been something itchy
Speaker 2: in the air, because within a very short amount of
Speaker 2: time we got two different questions about itching and scratching.
Speaker 1: So let's go ahead and hear the questions.
Speaker 5: I'd like to know what causes itches and why does
Speaker 5: scratching stop them. I don't mean itches that have a
Speaker 5: clear source medicine, side effects, bug bites, rashes, irritating clothing scenes,
Speaker 5: et cetera. I mean when you're just going about your
Speaker 5: day and suddenly some random part of you itches. How
Speaker 5: will you scratch it the itch stops?
Speaker 4: What's up with that? Hey, I'm loving the show. I
Speaker 4: wonder if you could answer a question for me. This
Speaker 4: might be one for Kelly. I've heard recently about a
Speaker 4: study which said, I think it was in mice, that
Speaker 4: if you scratch an itch, then it's beneficial because that
Speaker 4: allows antibodies to go to the site and to clear
Speaker 4: up any infection. But then there was another study, also
Speaker 4: in mice, saying that scratching and itch is problematic because
Speaker 4: it activates pain nerves, which then causes more riching and
Speaker 4: more inflammation. Which is it, Should I ignore the urge
Speaker 4: to scratch an itch or should I just go ahead
Speaker 4: and scratch it. Keep up the good work. Thanks.
Speaker 3: I think these questions are pretty deep. They're not really
Speaker 3: just surface level, you know. I think they're really dig
Speaker 3: down into what's going on. I didn't eat the skin, yeah.
Speaker 1: And I had a ton of fun digging in.
Speaker 2: And actually, it turns out that our understanding of itching
Speaker 2: has apparently undergone some pretty major changes in the last
Speaker 2: few decades. So initially we thought that itching was a
Speaker 2: minor form of pain, which would suggest that it's using
Speaker 2: the same pain receptors. And it's just sort of like,
Speaker 2: if you tickle the pain receptors just a little bit,
Speaker 2: you get an itch, but when you really hurt them,
Speaker 2: then you get pain.
Speaker 3: But back up and give me the bigger picture here.
Speaker 3: When you say pain receptors, you're talking about like nerve
Speaker 3: endings just under the skin. And I don't know enough
Speaker 3: biology to even know, like, are there different nerves for
Speaker 3: pain and for like cold and for other stuff? How
Speaker 3: does that all work?
Speaker 1: Oh? Yeah, great questions.
Speaker 2: So there are different nerves for different things, and so
Speaker 2: we do have some nerves that specifically are there to
Speaker 2: tell us about pain. And so for anyone who's gotten
Speaker 2: tattoos out there, you know, that there are some areas
Speaker 2: that hurt to get tattooed more than others. Daniel, you're
Speaker 2: shaking your head, yes, knowingly. Do you have tattoos?
Speaker 3: I do not, but I have a teenager who wants
Speaker 3: to get tattoos, and so we've had lots of conversations
Speaker 3: about making ferman decisions for your body.
Speaker 1: Got it okay.
Speaker 2: So there are some parts of your body that have
Speaker 2: more pain receptors than others, and those areas tend to
Speaker 2: hurt a little bit more when you get tattoos. And
Speaker 2: what these receptors do is they deliver messages from like
Speaker 2: the surface of your skin up to your brain to say, oh,
Speaker 2: something hurts, and then you respond to it, and often
Speaker 2: you respond to it without even really thinking about it.
Speaker 1: You have sort of a reflexive response.
Speaker 3: And so, for example, I know that I have a
Speaker 3: lot of nerves and the tips of my fingers, so
Speaker 3: I could tell the difference between one needle and like
Speaker 3: two needles very close together, and the tips of my
Speaker 3: finger has been not like on my elbow because I
Speaker 3: have fewer nerves there. I can't resolve it. But that's
Speaker 3: a different nerve system than the ones that help me
Speaker 3: sense pain.
Speaker 2: Yeah, so we're getting a little bit outside of my
Speaker 2: area of expertise here, but I think that those are
Speaker 2: touch receptors that you would be detecting there, unless you
Speaker 2: were like stabbing those needles into your fingers, which I
Speaker 2: assume you're not. I think we're talking about touch receptors there,
Speaker 2: and we've got receptors for cold and for hot and
Speaker 2: stuff like that.
Speaker 3: So you were saying that people used to think that
Speaker 3: itching or stimulating the pain receptors the nerves that when
Speaker 3: something hurts, Yeah, that doesn't really make a lot of
Speaker 3: sense to me, because itching doesn't feel like pain. It
Speaker 3: feels like uncomfortable and enjoys me crazy, but doesn't hurt
Speaker 3: the same way.
Speaker 1: Yeah.
Speaker 2: Well, so I wonder if it was because sometimes if
Speaker 2: you itch for a really long time, you scratch and
Speaker 2: then it starts to hurt. And so maybe people were
Speaker 2: just like imagining a continuum there that doesn't exist. But also,
Speaker 2: it's not so surprising we got these two systems sort
Speaker 2: of mixed up because they have a lot of cross talk.
Speaker 2: There's a lot of times when you stimulate one system
Speaker 2: and it sort of interacts with the other. For example,
Speaker 2: when I got an epidural when I was pregnant with
Speaker 2: my second. The first one was natural, second one, I
Speaker 2: had an epidural.
Speaker 3: Uh not just like a Friday night epidural.
Speaker 2: No, yeah right, No, I mean fun not recreational.
Speaker 1: Recreational.
Speaker 3: Yeah, no judgments to anybody out there who does that,
Speaker 3: you know, just clarifying here.
Speaker 2: Yeah, fair enough, But that would be an expensive habit,
Speaker 2: I'm guessing, because I think you'd need to get insured.
Speaker 2: But anyway, so when I got my epidural, I started
Speaker 2: itching like crazy.
Speaker 1: And I didn't.
Speaker 2: Find like a paper that specifically said some people who
Speaker 2: get epidural.
Speaker 1: Scratch like crazy.
Speaker 2: But I found a couple of papers that were referencing
Speaker 2: how sometimes when you do something for pain, you get
Speaker 2: this weird itchy side effect, and sometimes when you do
Speaker 2: something for itching, you get this weird pain side effect.
Speaker 2: And so these two systems seem to have a lot
Speaker 2: of cross talk, and they interact, but they are separate. Interesting,
Speaker 2: and so we do have specific receptors for itch.
Speaker 3: We do, so we've like evolved a whole system to
Speaker 3: make you uncomfortable.
Speaker 2: Well, okay, so I would say that a lot of
Speaker 2: times it does seem like our itch system does things
Speaker 2: that are maladaptive. Give me a second to do a
Speaker 2: little bit more explaining, and then we'll get back to that.
Speaker 2: So you've got these itch receptors and they can be
Speaker 2: stimulated externally or internally. So externally would be like there's
Speaker 2: a tick crawling on your skin and you feel itchy,
Speaker 2: and your immediate response is to try to brush it off,
Speaker 2: and that is pretty adaptive. You know, you move it off,
Speaker 2: and now you don't have that tick on there anymore.
Speaker 2: And I'm very proud of my body because I feel
Speaker 2: like I am really tuned to ticks. I've almost never
Speaker 2: had one bite me, but I've taken loads off of me,
Speaker 2: so like I feel them when they're moving around, So
Speaker 2: that's good.
Speaker 3: That's definitely a plus. I understand that, like your body
Speaker 3: wants you to feel uncomfortable having that critter crawl over you.
Speaker 2: Yes, exactly, Like your attention needs to be drawn to
Speaker 2: that you need to take care of it right away.
Speaker 2: We also have responses to internal things like histamines and
Speaker 2: various things that your immune system does. So for example,
Speaker 2: if you in the winter have really dry hands and
Speaker 2: you like make a fist and your skin cracks and
Speaker 2: bleeds like mine does, your immune system responds to those
Speaker 2: cracks and it recruits to where those cracks are, and
Speaker 2: the presence of those immune system cells trigger your itch receptors.
Speaker 2: And that's why your hand gets itchy when it's all
Speaker 2: broken and bleeding.
Speaker 3: Help me understand why internal histamines trigger the same receptors
Speaker 3: as a tick crawling across myself. Does that make sense.
Speaker 2: For some reason, I'm not sure that it does make sense.
Speaker 2: So there's a couple of different hypotheses here. So one
Speaker 2: hypothesis is that our species itches as.
Speaker 1: Sort of like an evolutionary hold over.
Speaker 2: So we used to have fur, and it used to
Speaker 2: be that we would when we would itch, we wouldn't
Speaker 2: damage ourselves because the fur got in the way. But
Speaker 2: now we don't have fur, and so when we itch,
Speaker 2: we damage ourselves. And so it could be that most
Speaker 2: of the time when there was an immune response, maybe
Speaker 2: it was because, for example, there was a tick that
Speaker 2: had bit and the immune system was responding to it.
Speaker 2: And so if you scratch, and you scratch through your fur,
Speaker 2: you get that tick off. And you know, I can
Speaker 2: still imagine the immune system drawing your attention to the
Speaker 2: presence of a tick, and you know, the sooner you
Speaker 2: remove a tick, the better, because some of them don't
Speaker 2: give you the diseases they're carrying until they've been on
Speaker 2: there for a while. And now I feel like I'm
Speaker 2: crawling with ticks because we're talking about it.
Speaker 3: I hope everybody out there getting itchy and ticky.
Speaker 2: Yes, guys and gals, So yeah, I mean I think it.
Speaker 2: Sometimes scratching is good because it removes something, or maybe
Speaker 2: it recruits more immune cells.
Speaker 1: But sometimes scratching is just bad.
Speaker 3: So I think you're saying that itching on the surface
Speaker 3: is very clear. It's to help us get rid of
Speaker 3: something that's crawling across us and might bite us and
Speaker 3: is bad for us, And that itching internally might also
Speaker 3: be good because it's a signal that something is already
Speaker 3: bitten us, and if we scratch it, we could get
Speaker 3: rid of it. So it's not that they trigger exactly
Speaker 3: the same mechanism. It's like two ways to protect us
Speaker 3: from critters. But are they biochemically the same mechanism, Like
Speaker 3: does it tick crawling across your skin trigger the same
Speaker 3: histamines and that whole same channel, or are they two separate.
Speaker 2: Mechanisms Both mechanisms trigger the same itch receptors to send
Speaker 2: a message to your brain that says scratch. And I
Speaker 2: think in both cases you can get good information that
Speaker 2: tells you to scratch when you should scratch, but both
Speaker 2: externally and internally you can also get bad information. So,
Speaker 2: for example, your skin might be particularly sensitive to certain
Speaker 2: kinds of allergens, or you know, certain kinds of compounds
Speaker 2: and soap, right, and then you might start scratching for
Speaker 2: no good reason. And you know, same thing with your
Speaker 2: body responding internally by releasing histamines at places where you
Speaker 2: really don't need to be scratching. And additionally, when you
Speaker 2: start scratching, you can initiate what's called the itch scratch cycle.
Speaker 2: And here's what happens there.
Speaker 3: So this sounds like a nightmare.
Speaker 2: So you start itching, and when you start itching, we
Speaker 2: all know that it feels amazing often, and so what's
Speaker 2: happening there is that your itch signal is being overridden
Speaker 2: by a pain signal, because when you scratch, you're causing
Speaker 2: yourself a little bit of pain. And I think the
Speaker 2: rest of this explanation is a little bit like, here's
Speaker 2: what we think is happening, but we're not one hundred
Speaker 2: percent sure. But they think that after you scratch and
Speaker 2: your pain signal overrides the itch signal, you also release
Speaker 2: some serotonin, which makes you feel better and sort of
Speaker 2: makes the pain eventually go away. And so scratching feels good.
Speaker 2: But when you scratch, you often damage the skin a
Speaker 2: little bit, especially if you're giving it a really strong scratch.
Speaker 2: And if you give it too hard of a scratch,
Speaker 2: now you've caused damage, and that damage recruits more immune cells,
Speaker 2: which makes you itch even more. And so by itching,
Speaker 2: you can make yourself itchier. And so there are people
Speaker 2: who have chronic itching issues and they get stuck in
Speaker 2: this itch scratch cycle. You know, if you tell someone
Speaker 2: who's itchy, oh, just don't scratch it. The scratching is
Speaker 2: what's causing the problem. That's like maddening, I think to
Speaker 2: tell someone because once you've got an itch, how do
Speaker 2: you avoid scratching that itch?
Speaker 1: That's like all you can think about.
Speaker 3: This is fascinating to me to understand exactly what happens
Speaker 3: when you scratch an itch, because I do this all
Speaker 3: the time. I'm the kind of person who's very sensitive
Speaker 3: to mosquito bites. They like torture me, and if I
Speaker 3: have one that's like really buzzing, and I scratch it.
Speaker 3: It's like the greatest relief in the world. Oh my god,
Speaker 3: that feeling is just like it's not just that the
Speaker 3: itch goes away, like actually feels really good, but you're right,
Speaker 3: scratch it hard, then that really fades, and then the
Speaker 3: pain comes through and then it gets itchy again. And
Speaker 3: scattered through my house are like dozens of these itch
Speaker 3: relief sticks, oh, which I totally rely on, and their
Speaker 3: lile benagyl sticks, and they are antihistamines. So I think
Speaker 3: that personal piece of data that the anecdote supports your
Speaker 3: hypothesis there. But it's fascinating to hear about like the serotonin,
Speaker 3: Like that's why I feel good, Right, It's not just
Speaker 3: that the itch has stopped and the discomfort has gone,
Speaker 3: but there's something in my body that is making me
Speaker 3: actually enjoy it.
Speaker 2: That is the current hypothesis. Yes, I don't know that
Speaker 2: we've absolutely nailed that down. And it's interesting that you
Speaker 2: mentioned antihistamines because one of the reasons that we know
Speaker 2: we don't really understand itch well is that you can
Speaker 2: give somewhat antihistamines in a case where you think that
Speaker 2: should solve the problem. Yeah, and it doesn't, and so
Speaker 2: it is more complicated. And you know, for some people,
Speaker 2: if you've got an itch, you scratch it, that's the
Speaker 2: end of the story. But for other people, their immune
Speaker 2: systems are a little bit more sensitive. You scratch it,
Speaker 2: that recruits more immune cells and you start getting in
Speaker 2: the cycle. You also can get chronic itch for reasons
Speaker 2: that you know, we again don't understand really well.
Speaker 3: So, for example, chronic itch.
Speaker 1: I know chronic itch.
Speaker 3: I would never wish that on my worst enemy.
Speaker 2: I was listening to an interview on NPR's Fresh Air
Speaker 2: from a woman who has a disease. I think it
Speaker 2: was of her liver or kidneys, and it creates chronic itch.
Speaker 2: And we don't understand why that particular issue should result
Speaker 2: in chronic itch, but she itches all the time. There's
Speaker 2: also folks who have chronic itch related to mental health issues,
Speaker 2: so like when they get depressed or anxious, it kind
Speaker 2: of makes them itchy, and so they scratch.
Speaker 1: A lot more.
Speaker 3: What's the connection there, I don't think we know. Just
Speaker 3: another amazing mind body connection. You know, it's incredible to
Speaker 3: me how much your mental state influences your body's health.
Speaker 3: And vice versa.
Speaker 2: Yeah, I mean the only reason I ended up on
Speaker 2: anxiety medication is because I went to my doctor and
Speaker 2: was like, everything hurts, my stomach hurts, and why is it?
Speaker 2: And she was like, I think it's uh, you know.
Speaker 2: She didn't say I think it's in your head. She
Speaker 2: was much nicer about it. But yes, when we're stressed
Speaker 2: out or anxious or depressed, it impacts our body in
Speaker 2: weird ways. So yeah, the studying of chronic itching and
Speaker 2: how to relieve it is a big area where there's
Speaker 2: a lot of work that we still have left to do.
Speaker 2: So the first question that we had was why do
Speaker 2: you itch when there's nothing there to make you itch?
Speaker 2: And I think part of the answer could be that,
Speaker 2: you know, for some people it's a mental health thing.
Speaker 2: Maybe they're anxious and stressed and there is nothing there.
Speaker 2: But I think a lot of the times it's something
Speaker 2: did cause you to need to itch, But maybe it's
Speaker 2: just escaping your consciousness. So for example, maybe there's like
Speaker 2: some fiber in your shirt that your body is confusing
Speaker 2: as a tick, or there was something in your soap
Speaker 2: that's creating a little bit of an allergic reaction in
Speaker 2: your back.
Speaker 1: That you didn't know about.
Speaker 2: You know, I think in general, something usually initiates this
Speaker 2: need to scratch, but we just can't always tell what
Speaker 2: it was.
Speaker 3: And the second question I think is one that's to
Speaker 3: my heart, which is, tell me, Kelly, from the point
Speaker 3: of view of science, should I scratch or should I resist?
Speaker 3: Am I a bad person for scratching my itches? All?
Speaker 1: Right?
Speaker 2: One, you are not a bad person for scratching your itches.
Speaker 2: There is no judgment here U.
Speaker 4: Two.
Speaker 2: I think it depends on why you're itching. So the
Speaker 2: listener mentioned that there was a study in mice that
Speaker 2: found that if you scratched, it recruited immune cells to
Speaker 2: the area, and that maybe that immune cell helped you
Speaker 2: deal with an infection or something. So it's possible that
Speaker 2: under some conditions, maybe you're able to recruit more immune
Speaker 2: cells if you've got like an infection or something that's itchy.
Speaker 2: But I think in a lot of cases, itching will
Speaker 2: feel good, but there's some chance that something bad will
Speaker 2: happen afterwards, and that something bad would be you could
Speaker 2: maybe open up a wound and give yourself an infection,
Speaker 2: or you could start off a new round of the
Speaker 2: itch scratch cycle, and so well, I think there's nothing
Speaker 2: wrong with like giving a light scratch to a mosquito bite,
Speaker 2: or if you've got an itch, making sure you don't
Speaker 2: have an insect crawling on you or tick crawling on you.
Speaker 2: But in general, I think the answer, because it's biology,
Speaker 2: is it depends. And if you are going to scratch,
Speaker 2: if you can scratch with like I don't know, your
Speaker 2: knuckles or something to try to like not break the
Speaker 2: skin so much, that would be great. But you know,
Speaker 2: just at the end of the day, some of us
Speaker 2: we can't help but scratch, and it's it's just hard
Speaker 2: to avoid.
Speaker 3: All right. Well, now I have a question which you
Speaker 3: may be the only person in the world qualified to answer.
Speaker 3: What because it connects itches in space? Are there cases
Speaker 3: where astronauts had crazy itches they couldn't scratch because they
Speaker 3: were in a space suit? And what are you supposed
Speaker 3: to do?
Speaker 1: Oh, oh my gosh, that must have happened.
Speaker 2: So you know, you can, like I guess you could
Speaker 2: try to like rub your skin against the inside of
Speaker 2: the suit.
Speaker 3: And so I wish you all could see the dance
Speaker 3: Kelly is doing right now to mimic how to scratch
Speaker 3: your back inside a spacesuit.
Speaker 2: Yeah, there are so many things that sound uncomfortable about
Speaker 2: being in a spacesuit, and the most uncomfortable of which
Speaker 2: is elamination.
Speaker 1: Have we talked. Do you know what that means?
Speaker 3: No, it sounds like you're removing your skin.
Speaker 1: Maybe you're removing your nails. So those gloves, I'm so
Speaker 1: so yeah.
Speaker 2: So those gloves are really hard to bend. And there
Speaker 2: are some cases where people have tried to bend it
Speaker 2: and their nails have kind of got stuck in their
Speaker 2: nails are pulled up from the nailbit.
Speaker 1: I know, so gross. So anyway, and then.
Speaker 3: You can't scratch your itches because you have no more fingernails.
Speaker 1: Oh my gosh. Oh, so many layers of horror. Don't
Speaker 1: go to space.
Speaker 3: Well, I haven't been to space, but I've had the
Speaker 3: situation where I had a cast and had itches inside
Speaker 3: the cast, and you know, we've all devised that long
Speaker 3: scratchy tool you can stick underneath the cast. Yeah, but
Speaker 3: I can't imagine what you would do if you are
Speaker 3: on in like a six hour EVA and you had
Speaker 3: an itch and you just had to keep going.
Speaker 2: I would be so distracted. It would be so hard
Speaker 2: for me to finish the mission.
Speaker 3: All right, Well, let's check in with Jane and Kay
Speaker 3: to see if we scratched their itch, and then we'll
Speaker 3: take a break before we come back and go into
Speaker 3: outer space to answer more questions.
Speaker 4: Oh, Kelly, I'm so sorry for asking such a controversial question.
Speaker 4: I do hope people weren't scratching too much whilst listening.
Speaker 4: Did you answer my question? Well, you seem to say
Speaker 4: that I need to resist the urge to scratch, so
Speaker 4: I'll try my best. But Kelly, I was so proud
Speaker 4: of you that you resisted the urge to combine poop
Speaker 4: and parasites. In the answer, I understand the itch resulting
Speaker 4: from scabies. My infestation is mainly caused by their waste products.
Speaker 4: We thank you for answering my question. This is another
Speaker 4: reason why you're my favorite podcast.
Speaker 1: Okay, we're back.
Speaker 2: So imagine you are an itchy astronaut heading towards the
Speaker 2: ort cloud and Tim from the UK has a question
Speaker 2: about what that would be like.
Speaker 6: Hi, Daniel N. Kelly, Tim from the UK here love
Speaker 6: the podcast. Here's my question. The Orc Cloud surrounds our
Speaker 6: solar system and is filled with trillions of objects. He's
Speaker 6: one to three light years thick, so then surely our
Speaker 6: true view of the universe outside of the cloud must
Speaker 6: be getting obscured or obstructed. And why is our view
Speaker 6: of the night sky relatively permanent fixed points of light
Speaker 6: coming in from the stars. Surely there should be times
Speaker 6: when the stars are completely obscured by the massive objects
Speaker 6: in the cloud. If the cloud thins, then more of
Speaker 6: the stars should be visible. If the cloud thickens, then
Speaker 6: some of the stars should disappear.
Speaker 3: That's it.
Speaker 6: Keep up the good work by.
Speaker 3: Thanks Tim for this wonderful question and for giving us
Speaker 3: an opportunity to scratch your orty itch.
Speaker 2: All right, So when I was looking at your outline,
Speaker 2: there was a fact in your outline that absolutely blew
Speaker 2: my mind. So let's get to it. Let's jump into
Speaker 2: what is the Ork Cloud?
Speaker 3: So the Orc Cloud is a theoretical cloud of icy
Speaker 3: mini planets, meaning I.
Speaker 1: Thought we knew it existed.
Speaker 2: The fact that it's theoretical is blowing my mind. The
Speaker 2: Ork Cloud is a maybe.
Speaker 3: It's a maybe for exactly the reason that Tim is asking,
Speaker 3: Because we can't see it. Oh my gosh, we can't
Speaker 3: see it. We've never seen it. There's like one observation
Speaker 3: of a thing people think might have come from the
Speaker 3: Ork Cloud, and people think comets maybe probably come from
Speaker 3: the Ork Cloud. But the Ork Cloud itself is not
Speaker 3: something we've ever seen, and it's a shame because it
Speaker 3: would be amazing. So let's back up and remind people
Speaker 3: what is the Orc Cloud? Anyway? So we're talking really
Speaker 3: far out in the Solar System. So you know, the
Speaker 3: Sun is at the center, and the Earth orbits of
Speaker 3: what we call one a A and the big planets
Speaker 3: are at like five ish AU, and if you go
Speaker 3: all the way out to Pluto, it orbits at a
Speaker 3: radius of like forty ish AU. So like really far
Speaker 3: out there in the Solar system, right, But the Orc Cloud,
Speaker 3: if it exists, is two thousand to like one hundred
Speaker 3: thousand AU from the Sun. Oh my god, we're talking
Speaker 3: about like one to three light years. This is a
Speaker 3: big blob of objects that are very very very far
Speaker 3: away from where we are currently, so they're not technically
Speaker 3: part of the Solar System. They're sort of like captured
Speaker 3: by the Sun's gravity, but very very far out there.
Speaker 2: So when you say two thousand to two hundred thousand,
Speaker 2: is that a huge error bar or just a huge
Speaker 2: area that's occupied by the Orc Cloud.
Speaker 3: It's a huge area. So like if you were going
Speaker 3: to go visit the Orc Cloud, it would start at
Speaker 3: like fifty thousand AU and you'd still be going through
Speaker 3: and come out the other side somewhere around one maybe
Speaker 3: two hundred thousand AU. Oh my gosh. So it's a
Speaker 3: huge area exactly, and it has lots and lots of
Speaker 3: objects in it. Like the Oor Cloud is not like
Speaker 3: two little pieces of ice. We think. It has like
Speaker 3: trillions and trillions of little icy bits out there, a
Speaker 3: lot of them bigger than like one kilometer wide, billions
Speaker 3: of them bigger than twenty kilometers wide. So it's a
Speaker 3: lot of stuff. But space is really vast. You know,
Speaker 3: volume grows very quickly with radius, so as you get
Speaker 3: far and out there, we're talking about an incredible amount
Speaker 3: of space. So even though there's a lot of stuff
Speaker 3: in there, it all adds up to like five times
Speaker 3: the mass of the Earth if you clump it all together.
Speaker 3: It's spread out really, really far, so you wouldn't be
Speaker 3: like dodging asteroids like in Star Wars. You'd be like
Speaker 3: using telescopes to find an object even if you were
Speaker 3: in the middle of the Ork Cloud.
Speaker 2: Whoa so I had imagine that the ork cloud was
Speaker 2: dust and small rocks, but it makes more sense that
Speaker 2: the cloud is made of water. Or you said ice,
Speaker 2: Is that ice made of water? And how did water
Speaker 2: get out there?
Speaker 3: Yeah? Water is actually everywhere in the Solar System and
Speaker 3: in the universe. It's not just water ice though, there's
Speaker 3: like methane, ice and other frozen stuff. And it's not
Speaker 3: unusual to find ice or frozen water or frozen other
Speaker 3: stuff out there in the far Solar System. You know,
Speaker 3: Neptune and Urinus have a lot of these things in
Speaker 3: them as well. Anything past the frost line in the
Speaker 3: Solar System, which is the inner part of the Solar System,
Speaker 3: where the Sun's radiation is going to melt or vaporize
Speaker 3: any sort of water that's out there, you're going to
Speaker 3: find a lot of it. That's why Jupiter and Saturn
Speaker 3: are bigger, for example, because as those planets started to
Speaker 3: form in the early Solar System, they could gather ice
Speaker 3: because it was around, and so they could grow faster
Speaker 3: than the inner planets. So the sort of more solid
Speaker 3: stuff out there because the Sun's radiation hadn't blasted it
Speaker 3: into vapor all right.
Speaker 2: So there is maybe a massive cloud of ice, but
Speaker 2: maybe not.
Speaker 3: And it's sort of the third cloud. In our Solar system.
Speaker 3: Have the Asteroid Belt, which is past Mars, and it's
Speaker 3: a bunch of rocks left over that we think can't
Speaker 3: coalesce into a planet because of Jupiter's gravitational pull in
Speaker 3: the tidal forces. Then there's the Kuiper Belt which is
Speaker 3: out there that provides short period comets, and it's just
Speaker 3: like a bunch of icy rocks. But the Ork Cloud
Speaker 3: is maybe a thousand times further out than the Kuiper Belt,
Speaker 3: so it really is like a halo for the whole
Speaker 3: Solar System.
Speaker 2: And so the stuff that's out there in that cloud,
Speaker 2: can you give me a sense for like how much
Speaker 2: stuff is out there?
Speaker 1: Like if you mushed it all together, how much would
Speaker 1: you have?
Speaker 3: So it's like five times the mass of the Earth.
Speaker 3: So it's not a tiny amount of stuff, right, It's
Speaker 3: just spread out over an incredible area, you know how
Speaker 3: Like when you start with a tub of frosting, you're like, Oh,
Speaker 3: this is definitely gonna be enough frosting for this cake,
Speaker 3: and then you start spreading out the cake, You're like, uh, oh,
Speaker 3: this might not be enough frosting. Like the oork cloud
Speaker 3: is spread super duper thin. You know, it's like the
Speaker 3: sun is the most lightly frosted thing you've ever seen.
Speaker 2: I thought you're this, this is a bit of insight
Speaker 2: into me. Maybe I thought you were going to say,
Speaker 2: when you sit down with the frosting and a spoon,
Speaker 2: this is.
Speaker 1: Definitely more than enough dessert. And then you're like, no,
Speaker 1: I wanted more.
Speaker 3: You know, there's a warning on the side of the
Speaker 3: frosting that says not to be eaten on its own.
Speaker 1: Are you serious?
Speaker 3: I am serious?
Speaker 1: Why do they are? They like prohibiting joy in.
Speaker 3: This whole episode of the Hyperfixed podcast about exactly that
Speaker 3: you should go dig into it. It's a fun story.
Speaker 1: Oh all right, my family might be in a lot
Speaker 1: of trouble. I'll dig in anyway.
Speaker 3: I'm not a doctor, but I don't recommend that you
Speaker 3: eat all of I'm roasting by yourself. At least share
Speaker 3: it with your family.
Speaker 1: I share it with the kids, all right. So moving on, And.
Speaker 3: We're not one hundred percent sure what the org cloud
Speaker 3: is made out of because we've never seen it directly. Right,
Speaker 3: if we could see light bouncing off of it, we
Speaker 3: could understand how it reflects and absorbs light and we
Speaker 3: could get some spectrographic information, or if we had a
Speaker 3: great theory for how it formed, we can understand it.
Speaker 3: But we have a few various ideas for like how
Speaker 3: one gets an org cloud. One is that it's sort
Speaker 3: of the detritus from the formation of the Solar System.
Speaker 3: There's a lot of like gravitational interactions, and sometimes things
Speaker 3: get sort of tossed out of the center, you know.
Speaker 3: We think, for example, there might have been another gas
Speaker 3: giant that in the early part of the Solar System
Speaker 3: because of the push in the pull of the various
Speaker 3: other planets, could have gotten tossed out. It's not that
Speaker 3: easy to stay in orbit. If you get a big
Speaker 3: enough push from something else, you might find another orbit
Speaker 3: or you might just be lost. And so these orc
Speaker 3: cloud objects might be like little bits that were formed
Speaker 3: closer to the Solar System and then got kicked out
Speaker 3: and ended up in a stable orbit very far from
Speaker 3: the Solar System.
Speaker 1: Whilst we could have had like another Saturn, yeah, but
Speaker 1: now it's out in the ork cloud. That's crazy exactly.
Speaker 3: Or it could have been that as our Sun was forming,
Speaker 3: there was another star that was forming nearby stars tend
Speaker 3: to form in clumps. Right, you have a huge cloud
Speaker 3: of gas that collapses into a solar system, but doesn't
Speaker 3: usually collapse into one solar system, It collapses into several
Speaker 3: based on where the over densities were in that gas cloud.
Speaker 3: And so it could have like exchanged material with sister
Speaker 3: stars and this old clouds could be like, you know,
Speaker 3: the last bit of that tug of war between the stars.
Speaker 1: Huh.
Speaker 2: So we've got theories for why it exists, but what
Speaker 2: is our evidence that it exists? Do we just think
Speaker 2: that it exists because we have some theories saying it should,
Speaker 2: or has someone like look through a telescope and been
Speaker 2: like kind of looks like a cloud out there.
Speaker 3: Yeah, why would anybody imagine this thing exists if we've
Speaker 3: never seen it? Right, Well, one of the original reasons
Speaker 3: for this concept was to explain long period comets. So
Speaker 3: comets are ice balls that plummet towards the center of
Speaker 3: the Solar system, go around the back of the Sun,
Speaker 3: and then zoom back out. And they can have shorter periods,
Speaker 3: you know, years, decades, or they can have longer periods
Speaker 3: hundreds of years, And people wonder, like, where do those
Speaker 3: ice balls come from that. They take hundreds of years
Speaker 3: to orbit the Sun, and so they imagine maybe there's
Speaker 3: a huge cluster of these balls out there, sort of
Speaker 3: floating in distant space, and sometimes one of them gets
Speaker 3: perturbed and falls in towards the inner Old System and
Speaker 3: becomes a comet. So this is where the hypothesis of
Speaker 3: the Ork cloud comes from. Oh interesting, yeah, and highlights
Speaker 3: something which I think is often overlooked, which is comets
Speaker 3: are a real danger. You know, people think about asteroids
Speaker 3: hitting us, and we monitor the asteroid belt and that's cool.
Speaker 3: But like asteroids, we can see, we can predict, and
Speaker 3: mostly we know where the big ones are. But they're
Speaker 3: also not that far away from us. So if they
Speaker 3: hit us, they're not going that fast. But comets they
Speaker 3: come out of the darkness, right, We have no idea
Speaker 3: the trillions of them out there. They can just get perturbed,
Speaker 3: comes suddenly out of the darkness, and by the time
Speaker 3: they hit the Earth, they're going incredibly fast. And so
Speaker 3: like in terms of existential danger, like comets in the
Speaker 3: Ork Cloud are a huge gun loaded with trillions of
Speaker 3: bullets pointed at the Earth.
Speaker 2: And if existential dread is your jam, you should check
Speaker 2: out our earlier interview with Phil Plate where we just
Speaker 2: talked about the many ways the universe is trying to
Speaker 2: kill us exactly.
Speaker 3: And so we've never seen the work Cloud, but we've tried.
Speaker 3: You know, the Oork Cloud is so far that is
Speaker 3: past Voyager one, which is the probe the humanity is
Speaker 3: sent out into space and is the furthest fastest human ship.
Speaker 3: It might reach the beginning of the Oor Cloud in
Speaker 3: three hundred more years, though the power on that thing
Speaker 3: is rapidly running out. But of course we can also
Speaker 3: try to see the or Cloud from Earth. And this
Speaker 3: gets really to Tim's question, like why isn't it blocking
Speaker 3: our view? It's not blocking our view because it's a
Speaker 3: lot of really really tiny objects super far away. It's
Speaker 3: like if an astronaut threw sand into space, it wouldn't
Speaker 3: block your view, right, And that's effectively what's going on here.
Speaker 3: They're really small. Each object, because it's so far away,
Speaker 3: would block the tiniest little portion of the night sky.
Speaker 3: So even though there are so many of them, they
Speaker 3: don't add up to blocking much of your night sky.
Speaker 3: But it's something that people are looking for. The way
Speaker 3: you could see the Ork Cloud is exactly. That is
Speaker 3: to see, like, can we see an object pass in
Speaker 3: front of a star? These little mini star eclipses would
Speaker 3: give us a hint that the Oorkcloud is real. And
Speaker 3: then it's out there, and there is one tentative observation.
Speaker 3: This object called Sedna, we think is one hundred and
Speaker 3: forty billion kilometers from the Sun. It's a tentative observation
Speaker 3: of this thing.
Speaker 2: Oh my gosh, that's I mean, to be able to
Speaker 2: see a teeny tiny object passing in front of the
Speaker 2: Sun seems to me like it would require amazing telescope abilities.
Speaker 3: Yeah, exactly. And Sedna is really hardest spot. It's twenty
Speaker 3: times further away from the Sun than Pluto, so its
Speaker 3: orbit is at about one thousand AU and it's a
Speaker 3: very very elongated orbit. But you know, it's just probably
Speaker 3: one of like zillions and zillions of things that are
Speaker 3: out there that we can just barely spot. But as
Speaker 3: we improve our telescopes, we'll get a clearer view of
Speaker 3: what's out there in the Oork Cloud, which is important
Speaker 3: because the better we understand the Orc Cloud, the better
Speaker 3: we're able to model in and predict what might happen.
Speaker 3: You know, every once in a while, another star comes
Speaker 3: near our star, and when they approach each other they
Speaker 3: can gravitationally nudge on each other. There's ort clouds potentially
Speaker 3: stimulating like a shower of comets into the inner Solar System.
Speaker 3: And yet, doesn't that seem like something we'd like.
Speaker 2: To understand when you say every once in a while,
Speaker 2: I hope you mean every like a few billion years,
Speaker 2: not in my lifetime, or what does everyone's in a
Speaker 2: while mean?
Speaker 3: There is a prediction that in one point three million years,
Speaker 3: another star is going to come within around twenty or
Speaker 3: thirty light days of our star, and so yeah, it's
Speaker 3: not going to be for a while.
Speaker 1: That's good. Yeah, I don't suspect I'll still be around
Speaker 1: by that point.
Speaker 3: But you know, the Sun oscillates relative to the galaxy.
Speaker 3: It doesn't just go around the center of the galaxy.
Speaker 3: It goes up and down through the plane of the
Speaker 3: galaxy like every thirty million years or so. So it's
Speaker 3: not like our galactic neighborhood. It's constant. You know, we're
Speaker 3: always zooming through the galaxy and changing our neighbors, and
Speaker 3: so they can come and go, and that affects the
Speaker 3: ork cloud, and you know, life on Earth.
Speaker 2: That's so amazing to me, how many things are happening
Speaker 2: at the very tiny scales and absolutely huge scales that
Speaker 2: you mess Like the other day, I was walking and
Speaker 2: I saw this little shimmer in front of my face
Speaker 2: and it was a baby spider. When they eventually go
Speaker 2: off to start their lives, they release a tiny little
Speaker 2: bit of silk that catches the air and they it's
Speaker 2: called ballooning, and they sort of balloon off. And there's
Speaker 2: all these little things that are happening that you only
Speaker 2: get a glimpse of very rarely, and you're missing it
Speaker 2: on the micro scale, and there's all this Like I
Speaker 2: just now learned that we're on a carousel around the
Speaker 2: galaxy and I was missing that too.
Speaker 1: It's amazing.
Speaker 3: Well, you're right, there is so much going on in
Speaker 3: the universe. We perceive a tiny little bit of it.
Speaker 3: We pay attention to an even smaller slice, and we
Speaker 3: understand and even smaller slice of that. And so we
Speaker 3: hope this podcast helps open up your eyes and your
Speaker 3: mind to what's going on in the rest of the universe.
Speaker 3: And so Tim tell us, if we have successfully stretched
Speaker 3: your brain out to the edges of the Ord Cloud,
Speaker 3: and explained why it doesn't block your view of the
Speaker 3: beautiful night sky.
Speaker 6: Let us know, guys, Thanks very much, keep up the
Speaker 6: good luck.
Speaker 3: All right, we're back and we're answering questions from people
Speaker 3: like you who are curious about the universe and want
Speaker 3: to know how things work. Please send us your questions
Speaker 3: to Questions at Daniel and Kelly dot org. We'd love
Speaker 3: to have you on the pod. So we've talked about itches,
Speaker 3: we've talked about space, and now we're going to zoom
Speaker 3: back in to talk about something that's happening right in
Speaker 3: your backyard. Humans aren't the only clever engineers on the planet.
Speaker 2: Maybe we'll see that's the payoff at the end. So
Speaker 2: let's go ahead and listen to a question from Eric
Speaker 2: in Idaho.
Speaker 7: Hey, Kelly, I was inspired by your passion for byology
Speaker 7: on the show and came across something called the honeycomb conjecture.
Speaker 7: Bees create hexagons for a fascinating reason, and in the
Speaker 7: last couple of decades a gentleman named Thomas Hales prove
Speaker 7: the conjecture using math.
Speaker 3: I have a few.
Speaker 7: Questions for you that I'd love to get your thoughts on.
Speaker 7: What is the history behind the conjecture, why do bees
Speaker 7: create hexagons?
Speaker 3: To begin with? What are the advantages to do in this?
Speaker 7: Also do biologists see any other species creating hexagons? And
Speaker 7: also I've been thinking a lot about math, and we
Speaker 7: all know math and physics go hand in hand. However,
Speaker 7: I don't hear much about mathe and biology going together.
Speaker 7: How prevalent is math and biology? Do you use it
Speaker 7: daily in your research? One thing too, I've been thinking
Speaker 7: about a lot is that some physicists believe that the
Speaker 7: universe nature is inherently mathematical. What do biologists say on
Speaker 7: this matter? What is their opinion? Is the universe? Is
Speaker 7: nature inherently mathematical? Or is this just the language that
Speaker 7: we human beings create to describe such crazy things like
Speaker 7: hexagons in nature? All right, I certainly appreciate everything you
Speaker 7: and Daniel do. Thank you for considering my questions.
Speaker 3: Eric is a long time listening to this show and
Speaker 3: a frequent emailer, and we love hearing from him. If
Speaker 3: you would like to email with us and have us
Speaker 3: answer all your science questions, please please please write to
Speaker 3: us to questions at Daniel and Kelly dot org. We
Speaker 3: mean it anyway, Kelly, what can you tell us about
Speaker 3: the honeycomb conjecture and bees. How long have people been
Speaker 3: thinking about this?
Speaker 2: Well, first of all, I love this question because it's
Speaker 2: a nice intersection of physics and biology, and so you know,
Speaker 2: I'll expect you to give most of the answer here,
Speaker 2: Daniel totally.
Speaker 1: No, I'm just kidding. I'm just kidding.
Speaker 2: I did my research, all right, So this is a
Speaker 2: question we've been asking.
Speaker 1: Ourselves for a really long time.
Speaker 2: So around thirty six BC, this guy, Marcus Tarentius Vero
Speaker 2: sorry about my pronunciation as ever, was writing a book
Speaker 2: about agriculture and he mentioned that honey bees make hexagonal
Speaker 2: honeycombs and that there was some debate about why this happened.
Speaker 2: And one of the first options was, well, bees have
Speaker 2: six legs, honeycombs have six sides.
Speaker 1: Maybe bees are just like using their.
Speaker 2: Legs to kind of determine the like vertices of the
Speaker 2: honeycomb and it so maybe it just has something to
Speaker 2: do with the fact that they have six legs.
Speaker 1: There was some connection there.
Speaker 3: Interesting. Well, I mean, you notice simple patterns, you draw
Speaker 3: dotted lines between them. Sure it makes sense?
Speaker 1: Yeah, sure, Then you test your conjectures.
Speaker 3: So how do you test that? You like, cut some
Speaker 3: legs off of bees and see if they make square honeycombs.
Speaker 2: I mean, yeah, that you could do that, you could,
Speaker 2: but we don't. It turns out we don't need to
Speaker 2: because actually the first thing you should do is make
Speaker 2: careful observations. And as we're gonna get to later, if
Speaker 2: you make careful observations, you'll see that actually bees are
Speaker 2: making circles that then melt into like a hexagonal shape.
Speaker 2: And so so if you just watch, you'd be like, oh, actually,
Speaker 2: it doesn't matter that they have six legs because they're
Speaker 2: just making circles.
Speaker 3: You're saying that bees when they originally make their honeycomb,
Speaker 3: they're making perfect circles or very close to it, and
Speaker 3: they just relax into honeycombs. Yes, wow, I had no idea.
Speaker 2: Well wait till we're going to get to in a
Speaker 2: little bit more details. So one of the interesting questions
Speaker 2: that arise here than I think, is our bees purposefully
Speaker 2: making hexagons or not our bees Nature's mathematicians or you know,
Speaker 2: is that giving them too much credit? But so the
Speaker 2: reason it's exciting that they're making hexagons is the second option,
Speaker 2: which is that they are purposefully making hexagon shapes through
Speaker 2: some mechanism that we'll get to later, because hexagons maximize
Speaker 2: the area inside. So since Pathagoras's time, we've known that
Speaker 2: some shapes do what's called tile the plane, which is
Speaker 2: to say, they fill a flat space without overlapping one
Speaker 2: another or creating any gaps. Some of the shapes that
Speaker 2: we've sort of studied the most in terms of tiling
Speaker 2: the plane are triangles, squares, and hexagons. There are some
Speaker 2: other shapes that do this.
Speaker 3: Too, and this is actually a really fascinating area of mathematics,
Speaker 3: like finding shapes that tile the plane and new shapes
Speaker 3: that tile the plane. Something this crazy discovery of an
Speaker 3: object that can tile an infinite plane without ever repeating
Speaker 3: a pattern, which is super amazing. This call an Einstein shape.
Speaker 3: And the best part of this story is that wasn't
Speaker 3: developed by like a professional mathematician, but like a craftsman,
Speaker 3: a guy who's just like good with stuff, and he
Speaker 3: built like a physical model to explore this anyway, super fascinating.
Speaker 3: That's amazing though, total digression though, So you're telling us
Speaker 3: about people thinking about tiling the plane way back in
Speaker 3: the time of like Greek geometricians.
Speaker 2: Yes, right, So people have been talking about tiling the
Speaker 2: plane for a long time. But one of the cool
Speaker 2: things about hexagons is that, you know, say you're considering triangles, squares,
Speaker 2: and hexagons to tile the plane. If you want to
Speaker 2: maximize the volume inside of the shape, then for the
Speaker 2: same perimeter for each of those shapes, hexagons maximize the
Speaker 2: volume inside, which you would want if you're storing honey
Speaker 2: or babies or something in place in there.
Speaker 3: Or babies in honey or something honeybabes, honey babes. And
Speaker 3: I guess the idea here is you want to be economical,
Speaker 3: and so you want to store as much as possible
Speaker 3: while using the minimal amount of building materials.
Speaker 2: That's right, because the building materials is wax that they
Speaker 2: have to make, and so you want to minimize the
Speaker 2: building materials you need and maximize the space inside.
Speaker 3: So I love when mathematics intersects with biology, and it
Speaker 3: gives us a reason. The hypothesis, I guess is that
Speaker 3: bees have somehow evolutionarily discovered that this is the most
Speaker 3: efficient way to store their honey by building hexagons.
Speaker 2: Yeah right, And it wasn't actually proved mathematically that this
Speaker 2: was a good strategy for the honeybees until Thomas Hales
Speaker 2: did it in two thousand.
Speaker 3: Two thousand AD AD.
Speaker 1: Yes.
Speaker 3: Wow, I love these mathematical questions that are like open
Speaker 3: for millennia and then some dudes like, I'm going to
Speaker 3: tackle that. Yeah, let's do that tomorrow.
Speaker 2: I'm guessing it was more than just tomorrow, but it
Speaker 2: was a like thirty six page proof, which I will
Speaker 2: admit I just kind of.
Speaker 1: Like scan scan scan scan scan scan. I didn't check
Speaker 1: his math.
Speaker 4: Wow.
Speaker 3: I love that. That's incredible.
Speaker 2: I mean, I think for some of these questions it
Speaker 2: could be because nobody was like I have to know
Speaker 2: if the honey bees are doing it right, Like there
Speaker 2: might have been more pressing questions, but it's a fascinating
Speaker 2: question to answer.
Speaker 3: All right, So we know now that hexagons are the
Speaker 3: best way to store honey. Do the bees know that?
Speaker 1: Yeah?
Speaker 2: So the answer at the end of the day is
Speaker 2: that we really don't know. So I watch some videos
Speaker 2: where people are like, oh, bees are Nature's mathematicians.
Speaker 1: They make hexagons, and I'm like, oh, I like that.
Speaker 1: That really sounds beautiful.
Speaker 2: But so then the question is, like, what do the
Speaker 2: bees know in terms of what they're doing and of course,
Speaker 2: you know, we can't ask the bees what they know,
Speaker 2: so we'll never really know. But as we mentioned a
Speaker 2: little bit earlier, they do start by making circles out
Speaker 2: of the wax, and as things sort of heat and
Speaker 2: then cool, they end up sort of changing their shape
Speaker 2: into hexagons over time. And I think you see this
Speaker 2: also with bubble rafts and Daniel, maybe you can explain
Speaker 2: why this is the case. This is where I thought
Speaker 2: Daniel's gonna chime in here, but maybe I'm wrong. So
Speaker 2: you make a bunch of little circular bubbles and they
Speaker 2: sort of find the spaces in between, and over time
Speaker 2: they sort of settle into hexagons, and I think that's
Speaker 2: like surface tension pulling them together into more efficient shapes.
Speaker 1: Does that sound right?
Speaker 3: Yeah, So what's happening there is the universe is optimizing it, right,
Speaker 3: not the bees, not the bubble raft designer. It's just like,
Speaker 3: if you're gonna squeeze a bunch of bubbles together, they're
Speaker 3: going to end up forming a hexagon shape because otherwise
Speaker 3: they're gonna pop, right, And so if you want to
Speaker 3: keep bubbles open and minimize the amount of popping, then
Speaker 3: you're going to pack them as hexagons. That just sort
Speaker 3: of makes sense. Yeah, And so it seems like we
Speaker 3: can't give credit to the bees for that, right. If
Speaker 3: they're building circles in the universe, is like, yeah, we're
Speaker 3: going to turn these into hexagons. Then that's just the
Speaker 3: mathematics of the universe. Isn't that physics?
Speaker 2: Well that would be boring, but so, uh, just kidding.
Speaker 2: So hold on, So when the bees are putting their
Speaker 2: circles in, they have to place the circles in certain
Speaker 2: ways so that you get the hexagons.
Speaker 1: If they put them.
Speaker 2: In there all randomly, then you wouldn't necessarily get like
Speaker 2: the the near perfect hexagons that you get. And so
Speaker 2: I don't think that they are saying, oh, we've got
Speaker 2: to do it this way, because if you place them
Speaker 2: this way, when they finally make their final form, they're
Speaker 2: going to be a hexagon, which is the mathematically ideal
Speaker 2: shape for our honey storage needs. But I do think
Speaker 2: they have some programming in there that helps them make
Speaker 2: sure that they put their circles in in a certain
Speaker 2: way so that when the wax settles, it will create
Speaker 2: a hexagon. But here's an interesting side thing. Paper wasps,
Speaker 2: which make their nests out of like fibers. So, for example,
Speaker 2: I was sitting on a bench the other day and
Speaker 2: a paper wasp came by, and it was it's an
Speaker 2: old wooden bench, and it was starting to like scrape
Speaker 2: the wood off of the top of the bench, and
Speaker 2: then it went back and it used it to make
Speaker 2: its paper nests. You're yawning, and I can't believe you're
Speaker 2: yawning at paper wasp, Daniel.
Speaker 1: They're so interested.
Speaker 3: But that's not a judgmental yawn. I was like a
Speaker 3: woke up too early yawn.
Speaker 1: No, I get that none of us get enough sleep.
Speaker 2: And so anyway, they also make hexagonal cells, and they
Speaker 2: don't get like you know, wax melts into the right shape.
Speaker 2: They start as circles. So the circles are sort of
Speaker 2: like up at the top point where the nest starts,
Speaker 2: and then as they build it out, you get hexagons.
Speaker 2: And so to me that's even a little bit more
Speaker 2: impressive because they do end up building the hexagons. But anyway,
Speaker 2: so it's all about positioning and not necessarily about going
Speaker 2: for hexagons in particular.
Speaker 3: Interesting and so in the end, are you going to
Speaker 3: give the bees credit? Do you think the bees are geometers?
Speaker 2: I give bees a lot of credit for a variety
Speaker 2: of reasons. Studies have shown that bees are really good
Speaker 2: at making economical decisions about which flowers to visit and
Speaker 2: how many times to visit them.
Speaker 1: They're good at communicating with one another.
Speaker 2: Where the great food sources are, and they are able
Speaker 2: to pull this trick off that maximizes the volume where
Speaker 2: they store their stuff. So I think they're impressive. Maybe
Speaker 2: not as impressive as we had initially imagined, but you know,
Speaker 2: nature doesn't need to find the most complicated solution to
Speaker 2: a problem if an easier mechanism gives you the right solution, amazing.
Speaker 3: The real question in my mind, though, is our b
Speaker 3: geometers or geometricians, which is the correct word.
Speaker 2: It feels like it's more your wheelhouse than mine, But.
Speaker 1: I think they're geometricians.
Speaker 3: Maybe in two thousand more years somebody will come along
Speaker 3: and figure that one out.
Speaker 2: You know what's really cute, though, there's these moths on
Speaker 2: my property, the inch worms, and the I think it's
Speaker 2: the family of inchworms are called geometer moths because they
Speaker 2: are like measuring the earth the way they move along,
Speaker 2: which I thought.
Speaker 1: Is super cute.
Speaker 3: It's cool, it's cute.
Speaker 2: So our listener had a couple different questions. One he
Speaker 2: wanted to know about the honeycomb conjecture. Two he wanted
Speaker 2: to know if other species create them. And we've talked
Speaker 2: about how paper wasps do. My husband Zach sent me
Speaker 2: a picture of tadpole eggs in our ponds that had
Speaker 2: naturally come together their form of hexagon.
Speaker 1: Oh, pretty cute.
Speaker 2: You see some plants make sort of hexagon shapes. So
Speaker 2: we do see this in nature in a couple different places,
Speaker 2: including in the bubble raft example. And then the final
Speaker 2: question was, you know math and physics go hand in hand,
Speaker 2: but you don't hear much about math and biology, you know.
Speaker 1: Yeah, Daniel jumps in there.
Speaker 2: I've heard Daniel critique biologists for not having error bars
Speaker 2: on our graphs and presentations.
Speaker 3: That's a difference. I'm criticizing biologists, not biology.
Speaker 1: Oh okay, got it, got it all right.
Speaker 2: So biologists do think a lot about math. So, for example,
Speaker 2: theoretical ecologists think a lot about how we can write
Speaker 2: equations that describe dynamics in a system, like predator or
Speaker 2: prey equations, or how an epidemic moves through a system.
Speaker 2: And so that requires a lot of maths, so they're
Speaker 2: thinking mathematically. There, we use a lot of statistics to
Speaker 2: try to understand what we observe, and you know, there
Speaker 2: are a lot of people who think about the world mathematically.
Speaker 2: And I think over the course of my twenty year
Speaker 2: career where I've been an ecologist, I've seen a much
Speaker 2: greater emphasis on trying to describe what we see, not
Speaker 2: just in terms of, you know, a qualitative description that's
Speaker 2: maybe a little poetic, which you know, I love reading
Speaker 2: those qualitative, poetic descriptions, but also trying to capture what
Speaker 2: you want in a more quantitative way and describing what
Speaker 2: you're seeing mathematically and then trying to explain why nature
Speaker 2: has resulted in that sort of equation.
Speaker 1: So, yes, biologists do use math a lot.
Speaker 3: On his last question, that's sort of a philosophy question,
Speaker 3: you know, is nature inherently mathematical? And the sort of
Speaker 3: an important philosophical question that we don't know the answer to,
Speaker 3: which is why we can use math to describe the universe.
Speaker 3: You know, you might imagine that math naturally describes the
Speaker 3: universe at the smallest scale, that fundamentally, the some equation
Speaker 3: you can write down to describe fundamental physics. But then
Speaker 3: why can you use math to describe like, you know,
Speaker 3: the predator preye reaction, or the geometry of hexagons, or
Speaker 3: you know, the shape of birds eggs or something. And
Speaker 3: that's the sort of mystery, like why these fairly simple
Speaker 3: mathematical stories emerge from the crazy, chaotic combination of fundamental
Speaker 3: bits of the universe. It's not something philosophers really have
Speaker 3: a handle on, so we don't know if it's something
Speaker 3: that is inherently part of the universe or sort of
Speaker 3: the way we are framing these questions, the way we
Speaker 3: think about things, you know, the sort of our mental language.
Speaker 2: Yeah, And one of the most popular phrases amongst people
Speaker 2: who do modeling in biology is that all models are wrong,
Speaker 2: some are useful.
Speaker 3: That's exactly correct, even of fundamental physics. Right, as far
Speaker 3: as we know, our description of the tiniest particles, it's
Speaker 3: not the end of the story. It's a model, and
Speaker 3: it's not true in the sense that it's not describing
Speaker 3: everything that's happening inside of it, but it's still useful.
Speaker 3: And you know, from a philosophical point of view, might argue,
Speaker 3: like what's the difference between true and useful, and model
Speaker 3: is just supposed to be useful. It's just supposed to
Speaker 3: predict the results of experiments. There's no deeper truth than that.
Speaker 3: But that's a whole nother philosophical rabbit.
Speaker 2: That's right, all right, Well, Eric, this was a fantastic question.
Speaker 2: It was great to hear from you again. Let's see
Speaker 2: if we scratched your itch on this be question.
Speaker 7: And Daniel, I just wanted to say a huge thank
Speaker 7: you for taking the time to answer my questions about
Speaker 7: the honeycomb conjecture on your show. I was fascinated to
Speaker 7: learn more about why best create hexagons and the advantage
Speaker 7: of that structure. It's incredible to think about how nature
Speaker 7: organizes like that. Hearing about whether other species create hexagons
Speaker 7: was really eye opening. In Your insights on how math
Speaker 7: plays a role and biology gave me a whole new perspective.
Speaker 7: I've always thought of math as more tied to physics,
Speaker 7: but now I can see how deeply it connects to
Speaker 7: the natural world in the universal ways I.
Speaker 3: Hadn't considered before.
Speaker 7: I did share what I learned with my wife, hoping
Speaker 7: it might ease her discomfort around bees, but I'm afraid
Speaker 7: she still doesn't feel any better about them. She says
Speaker 7: they're buzzing in geometry ways still gives her the creeps.
Speaker 7: Even so, your passion for biology really shines through, and
Speaker 7: I'm so grateful to have my curiosity spark.
Speaker 3: In such an amazing way.
Speaker 7: Thanks again for sharing your knowledge on the show.
Speaker 3: All right, Thanks very much everyone who engages with the
Speaker 3: podcast and sends us your questions, why don't you join
Speaker 3: their ranks? What is the question and that you most
Speaker 3: want an answer to that you think maybe it's impossible
Speaker 3: to answer, Send it to us. We'll give it a shot.
Speaker 3: Questions at Danielankelly dot org. Thanks for tuning in, Thanks.
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