Speaker 1: Welcome to Stuff to Blow Your Mind production of My
Speaker 1: Heart Radio. Hey, welcome to Stuff to Blow Your Mind.
Speaker 1: My name is Robert Lamb and I'm Joe McCormick. Today
Speaker 1: we're gonna be in a way we're continuing on past
Speaker 1: discussions concerning the Wheel. Um, also past discussions concerning uh
Speaker 1: like rolling creatures. But we're gonna be getting more specifically
Speaker 1: into the realm of the gear in this episode. Now,
Speaker 1: I have to say I'm anytime we get into one
Speaker 1: of these discussions, I'm always reminded of a few lines
Speaker 1: from The Omega Man. Uh. In part because it's in
Speaker 1: its own way, it's a weirdly interesting film. Also, I
Speaker 1: probably listened to a bit too much Wide Zombie back
Speaker 1: in high school, uh because there's some or maybe it's
Speaker 1: a Rob Zombie song that that samples this movie. But
Speaker 1: there's this one wonderful line from Anthony zerve Is character says,
Speaker 1: the creature of the Wheel, the lord of the infernal engines. Um.
Speaker 1: What is he talking about the vampires or is he
Speaker 1: talking about about Charlton Heston. He's talking about old Chuck Heston. There,
Speaker 1: he's the This man represents the Wheel and the technology
Speaker 1: of the wheel and all the terrible things that we're
Speaker 1: done with it. Um but wait, I recall the vampires
Speaker 1: using wheeled vehicles. Do they not? Don't they have like
Speaker 1: a sort of zombie mobile. Yeah. I'm not saying it
Speaker 1: makes sense. I'm not saying it's a fair criticism. I'm
Speaker 1: just saying that Anthony Zerva had a really cool voice.
Speaker 1: And uh and when he said these lines, it was like, yeah,
Speaker 1: that sounds cool. I don't know what it means exactly,
Speaker 1: but it sounds pretty cool. You know, it would be
Speaker 1: a really good movie Monster Bug Fight and and both
Speaker 1: are Charlton Heston movies. If you pick the vampires from
Speaker 1: the Omega Man versus the Adam Bomb Cult from the
Speaker 1: Second Plan into the Apes movie, you know, they're they're
Speaker 1: pretty similar. I think, pretty similar morbid humanoids. But I
Speaker 1: would like to see them duke it out, and Charlton
Speaker 1: has to I guess can just watch this time? Yeah?
Speaker 1: What was that beneath the Planet of the Apes? I
Speaker 1: always like that one. As far as any eight movies
Speaker 1: that came after Planet of the Apes, that one, that
Speaker 1: one always appealed to me. I'm not sure why. Uh.
Speaker 1: I remember there's a part where they sing a hymn
Speaker 1: to the atom bomb. Remember yep, they have just a
Speaker 1: big old atom bomb in there that they worship. I
Speaker 1: think it's like a minor key version of all things
Speaker 1: bright and beautiful. But it's interesting all these things are
Speaker 1: connected because we're dealing with with a human technology and
Speaker 1: the idea of worshiping the technology being bound to the technology,
Speaker 1: and and the wheel, and by virtue of the wheel,
Speaker 1: gears and machines being this thing that is particular to
Speaker 1: human beings, something that that that we have created. It's
Speaker 1: a part of our various civilizations. And I think it's
Speaker 1: interesting to think about humans as creatures of the Wheel Empire,
Speaker 1: because of course there have been plenty of cultures and
Speaker 1: civilizations where the wheel, at least in terms of of vehicles,
Speaker 1: has played no practical role. Perhaps that you know that
Speaker 1: you had the wheel as a toy, Perhaps it was
Speaker 1: used as a spiritual aid or device that could serve
Speaker 1: as a metaphor. But then certainly, by the time we
Speaker 1: get to the you know, the age of roads and engines,
Speaker 1: humanity very visibly becomes a people of the wheel. But then,
Speaker 1: as we'll discussed in this episode a little bit, you
Speaker 1: also get into this domain of wheels and gears of
Speaker 1: of wheels doing things that they don't have have anything
Speaker 1: directly to do with vehicles, but it's all about using
Speaker 1: the energy of the wheel to do other things. And
Speaker 1: yet at the same time, and this also makes me
Speaker 1: think of the field of bio memetics bioble metics, of course,
Speaker 1: as when we we say, okay, I have an engineering problem.
Speaker 1: I need to turn to the realm of nature for
Speaker 1: a possible solution, because I've only been working on this
Speaker 1: engineering problem for you know, X amount of time. But
Speaker 1: evolution has been working around similar engineering problems just for
Speaker 1: for millions of years. So perhaps we can we can
Speaker 1: cheat off of nature in that regard. But of course,
Speaker 1: one of the problems is that the wheel almost never
Speaker 1: comes up in nature itself. Gears almost never come up
Speaker 1: in nature. So biomometically, you're not going to turn to
Speaker 1: nature and say, oh, well, well there's a there's a
Speaker 1: solution involving the wheel that I might use. Oh, let's
Speaker 1: look and see how this particular creature uses rotary blades
Speaker 1: to fly that sort of thing. Yeah, you know, I
Speaker 1: actually really enjoy thinking about this in terms of comparing
Speaker 1: animal bodies to different types of machines, machine components, simple machines.
Speaker 1: You know the stuff you learn about in those first
Speaker 1: physics lessons when you're a kid. So you know, you
Speaker 1: know the lever and the inclined plane, and the and
Speaker 1: the pulley and the screw and all that. And I
Speaker 1: feel like when you do this exercise, there is one
Speaker 1: type of simple machine that absolutely dominates the landscape of biology,
Speaker 1: and that is the lever. Biology is full of levers.
Speaker 1: I think you could make an argument that almost all
Speaker 1: of the skeletal muscle in our bodies is designed by
Speaker 1: evolution for the operation of levers. Maybe there are some
Speaker 1: exceptions that aren't occurring to me, but I would say,
Speaker 1: if not all of them, almost all of them. So,
Speaker 1: for example, when you use your bicep to do an
Speaker 1: arm curl, you're curling a dumbbell. You know, the muscle
Speaker 1: primarily the bicep. I think also somewhat the muscle in
Speaker 1: your forearm is exerting the effort. The load is what's
Speaker 1: in your hand, it's your your fist, and the full
Speaker 1: crum is the elbow joint, and of course the bone
Speaker 1: is the lever. So I think most of the body's
Speaker 1: gross motor activity is based on the action of levers
Speaker 1: with joints as the fulcrum uh. And then, but then
Speaker 1: when you start looking for other simple machines and animal bodies,
Speaker 1: you can turn up some examples, but it suddenly gets
Speaker 1: a lot more difficult to scope things out. Like you
Speaker 1: can maybe make the argument that sharp teeth and fangs
Speaker 1: or a type of wedge which is technically a form
Speaker 1: of the simple machine known as the inclined plane. But
Speaker 1: then there are other types of of machines and machine
Speaker 1: parts that are pretty rare or even nonexistent in nature,
Speaker 1: and the wheel is a good one of these. There
Speaker 1: there are really only a few examples that people can
Speaker 1: point to of things that might be considered freely rotating
Speaker 1: wheels and axles. In biology, sometimes people bring up versions
Speaker 1: of the of bacterial flagella as something that sort of
Speaker 1: operates like a wheel, kind of spinning like a propeller
Speaker 1: to move the bacterium uh through through a liquid medium
Speaker 1: and uh. And then there are also I think some
Speaker 1: possible parts of animal digestive systems that may function kind
Speaker 1: of like a wheel. But animal body plans clearly favored
Speaker 1: the versatility of legs based on levers instead of wheels,
Speaker 1: And you can make a few different arguments about like
Speaker 1: why evolution overwhelmingly goes that route. You could you could
Speaker 1: say maybe it has something to do with just morphological precedence,
Speaker 1: like that levers are easier to evolve from the pre
Speaker 1: existing forms that were available for animal bodies to work
Speaker 1: on when in you know, adapting through small mutations. But
Speaker 1: you could also argue that there are natural uh, terrain
Speaker 1: negotiation advantages to levers. You know, if you're not in
Speaker 1: a world of clean paved surfaces, wheels can actually pretty
Speaker 1: easily get hung up on things, and you need the
Speaker 1: articulation of levers and limbs in order to say, uh,
Speaker 1: you know, get over rugged terrain, or to flip yourself
Speaker 1: back over if you fall on your back. I think
Speaker 1: it's also telling that when we look to the world
Speaker 1: of mythological creatures than beings, we don't see a lot
Speaker 1: of wheels, or at least we don't see a lot
Speaker 1: of wheels that are innately organic, and then if we do,
Speaker 1: we tend not to see a creature or a being
Speaker 1: that is supposed to be of this world. Um and uh.
Speaker 1: And perhaps there's some exception to this rule. That I'm overlooking,
Speaker 1: but I thought I might bring up a couple of examples. One,
Speaker 1: and I know I've mentioned this this critter on the
Speaker 1: show before. There is a demon by the name of Bure.
Speaker 1: I believe it is b u e R described in
Speaker 1: Johann of Vierst sixty three Grimore pseudo Monarchia demonium Um.
Speaker 1: This covers a number of different of supposed demons, and
Speaker 1: this demon Buer is the Great President of Hell. Kind
Speaker 1: of a goblin faced lion with kind of a wheel
Speaker 1: of five legs going around it, which I find reminiscent
Speaker 1: of the pet rail wheel which I mentioned in a
Speaker 1: previous Artifact episode, an experimental tank wheel that had legs
Speaker 1: on it um. So as the wheel turns, the legs
Speaker 1: are are placed down onto the ount uh. In this
Speaker 1: case they are goat legs, and I've I've read that
Speaker 1: they're supposed to symbolize the demon's ability to move in
Speaker 1: any direction. So I'm not entirely sure that we're even
Speaker 1: supposed to imagine this creature turning like a wheel or
Speaker 1: like a clock or something. But when I look at him,
Speaker 1: that's all I can see, Like he basically moves on
Speaker 1: the page or on the screen when I stare at him,
Speaker 1: and I can imagine I'm kind of lumping around along.
Speaker 1: You know. Well, I tend to think about um. When
Speaker 1: wheels are imagined in the imagery of mythology and religion,
Speaker 1: it's often to say something about the fact that the
Speaker 1: vision is boggling the mind it. You know, that it's
Speaker 1: transcending familiar forms and just completely awing you and humbling
Speaker 1: you with confusion. Uh So I think, for example, about
Speaker 1: Ezekiel's vision of the wheels in in in the Hebrew Bible,
Speaker 1: and and how the wheels there, Uh, it seems to
Speaker 1: me at least, I mean, I'm you know, no professional
Speaker 1: legsagy eat on that, but it seems like that they
Speaker 1: symbolize something about, uh, a concept that sort of like
Speaker 1: surpasses human understanding. You're looking at something that your mind
Speaker 1: can't even fit around. Yeah, I mean, we can easily
Speaker 1: imagine the various connotations that are being drawn in there.
Speaker 1: When you have a wheel like appearing in the sky,
Speaker 1: because you have the idea of technology, something created by
Speaker 1: rational beings, you have the idea of sort of cosmic
Speaker 1: wheels and circular forms related to the movements of the
Speaker 1: stars and the planets and so forth. Uh. And then
Speaker 1: the idea too that if if this is mixed with
Speaker 1: some sort of biological or faintly biological or hybrid form,
Speaker 1: that that is again something that is not reflected in nature.
Speaker 1: It is something there is something inherently unnatural about this,
Speaker 1: this hybrid being that is not even just part animal
Speaker 1: and part human. Are part of this animal and part
Speaker 1: that animal, but part flesh being and part cosmic or
Speaker 1: technological entity. Now then again, in nature and biology, you
Speaker 1: do find all kinds of round mechanisms and round bodies
Speaker 1: and even rolling forms. You know, lots of animals can
Speaker 1: roll up into a round shape and then roll their
Speaker 1: whole body. What you what really seems to be unusual
Speaker 1: in nature, And again maybe you can only find a
Speaker 1: few examples here and there that would seem to fit.
Speaker 1: This is a freely rotating wheel that somehow transfers energy
Speaker 1: within a broader context. So like the wheel and axle
Speaker 1: on a car that moves the car body the car,
Speaker 1: you know, the chassis stationary, and then the wheel turns
Speaker 1: to propel it forward. That's what you really don't find
Speaker 1: much of in nature. But if you're content with just
Speaker 1: like something round, that rolls. You can have a wheel
Speaker 1: spider rolling down a dune. You can have bugs that
Speaker 1: roll up into round shapes and roll all over the place.
Speaker 1: Even some mammals do that. Yeah, there are some examples
Speaker 1: of creatures that that form rolling shapes, granted, if the
Speaker 1: topography is correct. Uh. There's also, of course that the
Speaker 1: example of goat poop I've seen brought up. Granted, goat
Speaker 1: poop is not a self alive, but it is the
Speaker 1: product of of a biological organism. And the idea here
Speaker 1: is that the goat poop is nice and rounds so
Speaker 1: that it can roll away and hide itself. Uh in
Speaker 1: these kind of environments. But I advocate for goat poop personhood. Okay, Um.
Speaker 1: But but of course, one of the things about any
Speaker 1: of these rolling creatures is, of course, if it's going
Speaker 1: to roll, it's everything's gonna roll. There's not gonna be
Speaker 1: a stationary part all of the rolling creature, as in
Speaker 1: the same way that say, there would be the cart
Speaker 1: portion of an ox cart would remain the same. Uh.
Speaker 1: But when we look to some of our supernatural models,
Speaker 1: we do see things that work like this, of course
Speaker 1: in a very supernatural form. Uh. There's a wonderful wheel
Speaker 1: creature in um In Japanese traditions, there's a yokai known
Speaker 1: as one you know, the fire wheel, and he's a
Speaker 1: he's a pretty famous yokai. You've you've probably seen images
Speaker 1: of him, especially if you partake of various like anime
Speaker 1: um products, because he pops up in a lot of things,
Speaker 1: and think he pops up in some video games as well.
Speaker 1: He looks like a grumpy, giant human head sort of
Speaker 1: haloed by a burning, smoking ghost wheel, and we get
Speaker 1: the impression that the wheel is moving in the head
Speaker 1: is remaining stationary. He said to guard the gates of hell,
Speaker 1: and I've also read that in life he said to
Speaker 1: have been a cruel ruler who burned people on the wheel,
Speaker 1: so this is kind of his punishment. He haunts them
Speaker 1: the roads at night he made drag souls back to hell.
Speaker 1: And there's also a female variation called Catawaga. Okay, so
Speaker 1: this would seem to be more like that mechanism you
Speaker 1: don't really find in nature, if the head stays stationary
Speaker 1: while the wheel turns around it right, And of course
Speaker 1: in this too, we have just a it's not even
Speaker 1: pretending to be an entirely organic creature. It is this
Speaker 1: supernatural um combination of two or three different things. UM.
Speaker 1: But yeah, this is a pretty popular figure. The Power
Speaker 1: Rangers have even fought him on occasion. UM shows up
Speaker 1: in various anime titles, and I have to say, sometimes
Speaker 1: he looks a little bit like Dr robot Nick from
Speaker 1: the Sonic Games. So I wonder if Dr Robotnick was
Speaker 1: at all inspired by this yokai you know, a grumpy
Speaker 1: faced man machine with kind of a spherical design. Because
Speaker 1: Dr Robotnick is he's the Eggman, you know, so he's
Speaker 1: often in some kind of little like little circular pod.
Speaker 1: Why do I want to say that the the Dr
Speaker 1: Robotnick was supposed to be based on the appearance of
Speaker 1: Theodore Roosevelt. Do you know what I'm talking about? He
Speaker 1: does look like Theodore Roosevelt. Yeah, so that might be
Speaker 1: it instead. I don't know. I couldn't. I briefly looked around.
Speaker 1: I couldn't find anything that connected at Dr Robotnick. There's
Speaker 1: not a lot of scholarship on Dr Robotnick, it seems,
Speaker 1: unless I'm missing it. And if I am missing it,
Speaker 1: please send it to me. I want to read your
Speaker 1: your thesis. Okay, our new podcast is an oral history
Speaker 1: of Dr Robotnick. Um. Now there's a there's another throw
Speaker 1: some I am the Walrus, and some Teddy Roosevelt and
Speaker 1: your blender, and then there you go, oh yeah, there's
Speaker 1: definitely a It seems like there's definitely a Beatles connection
Speaker 1: there as well. Now, um, I was I was reading
Speaker 1: about this two particularly Yokai, and there's one more little
Speaker 1: story I ran across it. I have to share this was.
Speaker 1: I found this on Matthew Myers. Yokai dot Com has
Speaker 1: a profile of when Udo and shares a brief story
Speaker 1: that I haven't found anywhere else but it's it's too
Speaker 1: good not to share, and I'm probably just missing accounts
Speaker 1: of it elsewhere, but quoting this website, one famous story
Speaker 1: from Kyoto tells a woman who peeked out her window
Speaker 1: at one Udo as he passed through town. The demon
Speaker 1: snarled at her, saying, instead of looking at me, have
Speaker 1: a look at your own child. She looked back at
Speaker 1: her baby, who was screaming on the floor in a
Speaker 1: pool of blood. Both of its legs had been completely
Speaker 1: torn from its body. When she looked back out at
Speaker 1: one Udo, that child's legs were in its mouth being
Speaker 1: eaten by the mad grinning monster. What so it did
Speaker 1: he teleport that I don't Okay, yeah, yeah, I don't know.
Speaker 1: He's eating those babies eggs. He's a bad dude. That
Speaker 1: that's a bad dude. So anyway, I'll stop there with
Speaker 1: my wheel creatures. But this is suffice to say, just
Speaker 1: just bringing these up to drive home the fact that
Speaker 1: that I think we we have long not expected to
Speaker 1: find wheels and gears in the natural world. They are
Speaker 1: things of our creation. We are the people of the wheel, well,
Speaker 1: especially the gear. So that that was my original idea
Speaker 1: for the episode, was to focus on the idea of
Speaker 1: artificial gears versus possible examples of gears in nature. And
Speaker 1: while you can make arguments for a few examples of
Speaker 1: wheels in nature, the gear is really a different kind
Speaker 1: of story, except for this one really cool example that
Speaker 1: we're gonna be looking at today. So what is a gear? Well,
Speaker 1: you've seen gears before, but to actually define the concept
Speaker 1: what counts as a gear? I think I think you
Speaker 1: could say a gear is a set of rotating machine
Speaker 1: parts with interlocking teeth. So these can often take the
Speaker 1: form of a kind of flat circular plate, but they
Speaker 1: can also take the form of say like a long
Speaker 1: shaft that has teeth on the shaft, or they can
Speaker 1: even be non circular. There are more kind of square
Speaker 1: shaped gears and gears of all different kinds of shapes
Speaker 1: and sizes, but what's common to all of them is
Speaker 1: that they have teeth that interlock with each other and
Speaker 1: they use those teeth and rotation to transfer force rotational
Speaker 1: force known as torque. So they can transfer torque from
Speaker 1: one place to another, and they can also sometimes transform
Speaker 1: that force in some way as it is transferred. So
Speaker 1: gears can change the direction of rotational force. Like if
Speaker 1: you picture two interlocking wheel shaped gears, you rotate one
Speaker 1: of them clockwise, it'll actually rotate the other one counterclockwise,
Speaker 1: so that'll that'll perform one kind of change, or you
Speaker 1: can change the orientation of the torque by having the
Speaker 1: gears interlock at an angle. So think of, for example,
Speaker 1: how if you imagine a car that has the engine
Speaker 1: sending its rotational force its torque through a drive shaft
Speaker 1: that runs along the length of the car, then that
Speaker 1: energy has to be transferred to the wheels to get
Speaker 1: them rotating. In the direction that's parallel to the car's motion.
Speaker 1: So there are gears that interlock at angles there to
Speaker 1: transfer that force eventually to the wheels. But gears can
Speaker 1: also be used to gain mechanical advantage or change the
Speaker 1: speed of a rotational force in a mathematically predictable way. So,
Speaker 1: for example, if you use a bigger gear with more
Speaker 1: teeth to spin a smaller gear with fewer teeth, the
Speaker 1: smaller gear will spin faster than the larger one, and
Speaker 1: the change in speed will be proportional to the ratio
Speaker 1: of the tooth counts between the two differently sized gears.
Speaker 1: In other words, if you use a gear to drive
Speaker 1: a second gear with half as many teeth as the
Speaker 1: first gear, it will spin exactly twice as fast. To
Speaker 1: a certain stand. It almost feels like like wheel wizardry,
Speaker 1: because the wheel is doing its thing and and and
Speaker 1: if you're not going to do anything else, you can Okay,
Speaker 1: you can do various tasks and carry out various acts
Speaker 1: by interacting with that wheel on its terms. But by
Speaker 1: the use of gears, you can transform it. You can
Speaker 1: you can make the gear work in other ways. Um,
Speaker 1: And I think that's that's one of the fascinating things.
Speaker 1: So when we're when we're talking about sort of that
Speaker 1: lead from from wheel to gear. And of course, and
Speaker 1: this could be just as simple as why I don't
Speaker 1: want horizontal rotation, I want vertical rotation, that sort of thing, right,
Speaker 1: But it can also this last thing I mentioned about
Speaker 1: the predictable mathematical relationships between the intervals of rotation of
Speaker 1: tooth to gears. The fact that toothed gears are quantized, right,
Speaker 1: that you can like put a number to the number
Speaker 1: of teeth on a rotation that allows you to tightly
Speaker 1: control the ratios you know, how fast one spins in
Speaker 1: relationship to another one. That actually has made gears useful
Speaker 1: not just for say, applying force to things like you know,
Speaker 1: powering a machine or something, but also for tasks related
Speaker 1: to more abstract types of work, like measurements such as
Speaker 1: measuring intervals of time UM and not just in straightforward
Speaker 1: timekeeping devices like clocks. Of course, gears are very important
Speaker 1: in in um analog clocks, but even more complex applications
Speaker 1: like we see in one of the most intriguing artifacts
Speaker 1: from the ancient world, known as the Antiko theorem mechanism,
Speaker 1: which is widely considered the first known computer not a
Speaker 1: digital computer, but an analog computer, a computer that uses
Speaker 1: gears instead of semiconductors for information processing. UH. The antikothera
Speaker 1: mechanism was discovered in a Roman era shipwreck in the
Speaker 1: Mediterranean around the r nineteen hundred UH and this shipwreck
Speaker 1: traced back to a ship that sank probably in the
Speaker 1: first century CE. ROB. I've got an image for you
Speaker 1: to look at here that shows the actual remains of
Speaker 1: the mechanism alongside a modern reconstruction that was sort of
Speaker 1: reverse engineered and built by some experts who had studied
Speaker 1: this machine. The mechanism is now understood to have been
Speaker 1: an ancient mechanical or ory. An oorory is a is
Speaker 1: a working model of the movement of heavenly bodies, and
Speaker 1: this one would have been powered by a hand crank
Speaker 1: that operated gears. And this or ory would allow you
Speaker 1: to calculate the relative positions of heavenly bodies like the
Speaker 1: Moon and the Sun as they traveled through the zodiac
Speaker 1: out to specific future dates. UH. And I think it
Speaker 1: may it may also have tracked planetary motion as well,
Speaker 1: but that's less certain. I think that's a hypothetical mechanism
Speaker 1: that may have been present but may have been lost.
Speaker 1: When I look at it, I'm instantly reminded of those uh,
Speaker 1: those gear devices you find at museums and zoos where
Speaker 1: you can squash a penny and make it into a
Speaker 1: collector's token, which which I have to say, as as
Speaker 1: a parent, I have I have long realized that children
Speaker 1: are drawn to these like like flies to meet they
Speaker 1: they have to turn the crank, they have to watch
Speaker 1: those gears operate. Um and uh and And now that
Speaker 1: we've actually discussed gears a bit on the show, I
Speaker 1: used to be I was. I've long been very annoyed
Speaker 1: by it, like, oh, come on, don't mess with that.
Speaker 1: We're here to look at something else, and you're just
Speaker 1: gonna turn this gear on this machine that I'm not
Speaker 1: going to give you fifty cents and a penny for
Speaker 1: because it's it's a dumb invention. But at the same
Speaker 1: time they're interacting with the gears, they're getting to see
Speaker 1: the gears in motion and see some of that energy
Speaker 1: transference that we're talking about. Oh well, I mean yeah,
Speaker 1: it's a beautiful way. Actually, I think to educate kids
Speaker 1: about mechanical advantage, about like what machines can do. Because
Speaker 1: the kid, they know that they wouldn't have enough strength
Speaker 1: to smash a penny flat with their hands alone, but
Speaker 1: with their hands by operating a crank in a machine
Speaker 1: that has no external power source. It's just the power
Speaker 1: of their arm. But through the mechanical advantage created by
Speaker 1: this crank, the lever of the gears, they can smash
Speaker 1: a penny. That that's kind of that's that's empowering knowledge
Speaker 1: that there's a wizardry to that too. Behold the power
Speaker 1: of the gear. But anyway back to the antikotheram mechanism.
Speaker 1: So it was able to predict the future movements of
Speaker 1: heavenly bodies like the Sun and the moon, and also
Speaker 1: I think predict eclipses. And it managed the different time
Speaker 1: ratios between these these moving objects in the heavens by
Speaker 1: the use of gear ratios, gear ratios to calculate the
Speaker 1: intervals of these movements. So in a way, this was
Speaker 1: a calculator the different ratios between the number of teeth
Speaker 1: on the gears. We're doing math for you now. We
Speaker 1: know in the modern world, gears are useful in all
Speaker 1: kinds of machines. You find them everywhere they're in clocks,
Speaker 1: they're in cars, they're in fluid pumps, they're in mills
Speaker 1: and factory machines. But but you might wonder, okay, well,
Speaker 1: where did they first appear in the technological space, because
Speaker 1: you wouldn't necessarily expect to have found a computer for
Speaker 1: astronomical phenomena in the first century CE. But here it is.
Speaker 1: And probably actually it's even older than that. I think
Speaker 1: it's believed to have been. Uh. I don't know, maybe
Speaker 1: at least a hundred years old at the time it
Speaker 1: was lost in this shipwreck, so so clearly that that's
Speaker 1: taking gear math way way back. Uh. And I was
Speaker 1: trying to find some good sources on the ancient history
Speaker 1: of gears. I didn't come across anything that was super recent,
Speaker 1: so there may be discoveries since these sources I turned up.
Speaker 1: But um one that was interesting to me because it
Speaker 1: was by Derek John Desola Price, who was a British
Speaker 1: physicist and historian of science who was one of the
Speaker 1: investigators who worked on the antiko theorem mechanism. UH. He
Speaker 1: did a chapter that was in a book put out
Speaker 1: by the U. S National Museum Bulletin in nineteen five.
Speaker 1: De nine, called on the origin of clockwork perpetual motion
Speaker 1: devices in the compass, and in a short section on
Speaker 1: the earliest known examples of gears and geared mechanisms, he
Speaker 1: writes that the earliest evidence for the knowledge of tooth
Speaker 1: to gears um probably it goes back at least as
Speaker 1: far as the Greek mathematician and inventor Archimedes, who showed
Speaker 1: clear knowledge of of toothed gears, and he lived in
Speaker 1: the third century BC. But he also cites artifacts from
Speaker 1: ancient China that may indicate knowledge of of gears even
Speaker 1: farther back than that. He writes, quote, in China, actual
Speaker 1: examples of wheels and molds for wheels dating back from
Speaker 1: the fourth century BC have been preserved. One of the
Speaker 1: interesting things he mentions about some of these earliest examples
Speaker 1: of gears in the archaeological record, uh, He says, quote,
Speaker 1: A remarkable feature in these early gears is the use
Speaker 1: of ratchet shaped teeth, sometimes even twisted heliically so that
Speaker 1: the gears resemble worms intermeshing on parallel axles. But then
Speaker 1: he also calls attention to the fact that throughout much
Speaker 1: of history, UH, you know, definitely before the Industrial Revolution,
Speaker 1: a big use of a lot of a major use
Speaker 1: for gears in the technological space was in mills, in
Speaker 1: windmills and water mills, using large gears as a way
Speaker 1: of transferring force, often at a right angle to how
Speaker 1: these natural forces like the flow of water or the
Speaker 1: flow of wind, we're we're moving the primary turban. Yeah,
Speaker 1: or likewise to transition from say a horizontal paddle wheel
Speaker 1: into a vertical millstone, that sort of thing. Yeah. Yeah.
Speaker 1: Now another paper that you you turned up on. This
Speaker 1: comes to us from M. J. T. Lewis Gearing in
Speaker 1: the Ancient World, published in Endeavor seventy seventeen, number three
Speaker 1: from UM and I was reading through this one. This
Speaker 1: was pretty interesting. I'm gonna be some slight retreading of
Speaker 1: what we're very discussed. But basically, according to this this paper,
Speaker 1: we can trace the technology of of the gear to
Speaker 1: ancient Greeks of the third century b c. Which also
Speaker 1: according to um uh to Fagan at all in uh
Speaker 1: the seventy Great Inventions of the Ancient World. Uh. You
Speaker 1: know this is this is also the time and place
Speaker 1: where we see, at least according to ancient Greek and
Speaker 1: Latin technical authors, the birth of water powered milling UH,
Speaker 1: a technology that of course would be highly effective. But
Speaker 1: according to to uh To Lewis, here in Alexandria, the
Speaker 1: Greek kings of Egypt at the time the Ptolemy's they
Speaker 1: set up a research center called the Museum. I think
Speaker 1: we've talked about the museum in the past, right, perhaps
Speaker 1: even in our episode the Invention of the Museum, about
Speaker 1: the sort of the original usage of this word that
Speaker 1: sounds familiar, Yeah, yeah, So basically, various technological innovations were
Speaker 1: said to have emerged from this this sort of lab
Speaker 1: this kind of technological think tank and laboratory. Uh And
Speaker 1: according to such writers as hero Vitruvius and Phillow of Byzantium,
Speaker 1: they all point to the work of Tiscibius, who would
Speaker 1: have lived to eight five through to twenty two b
Speaker 1: c e. None of his actual writings survived, but he's
Speaker 1: said to have written various works on compressed air and hydraulics,
Speaker 1: and hero Vitrucius and Philo would all go on to
Speaker 1: write at length on these various machines and UH and
Speaker 1: and devices, various gear arrangements. Other great minds of that
Speaker 1: age and region, such as Archimedes, would also expand on
Speaker 1: these ideas as well. Now Lewis explains that we ultimately
Speaker 1: don't know where and when the earliest gears pop up
Speaker 1: in human history. Uh Tooth gears, he writes, already existed
Speaker 1: in the form of ratchet wheels that were used to
Speaker 1: hold a windlass against a load, and these might date
Speaker 1: back to Greek crane innovations from around five b c.
Speaker 1: E um he. He also points out that a bronze
Speaker 1: example of this has been found from about a century later,
Speaker 1: and this might have been used for hauling ships up
Speaker 1: a slipway. After this point, ratchets were widely used on
Speaker 1: catapults as a way of holding back all that potential
Speaker 1: firing energy. Um but, he writes, quote but the first
Speaker 1: toothed wheel for transmitting motion may have been a sprocket
Speaker 1: wheel driving a chain. This is attested by two machines
Speaker 1: described by Philo. One is a chain of buckets powered
Speaker 1: by a water wheel. The other is a repeater catapult
Speaker 1: built in roads by certain Dionysius of Alexandria, who cannot
Speaker 1: be precisely identified, but may have well worked before to
Speaker 1: eight two b c. E. So, the Greeks and the
Speaker 1: Romans obviously applied the subsequent technology to a number of tasks.
Speaker 1: But but Lewis raises the question did they invent all
Speaker 1: of this themselves or did they borrow or pick up
Speaker 1: on the ideas of others, And he writes that one
Speaker 1: possibility would be that they somehow got these ideas from China.
Speaker 1: In fact, he writes, this would be seemingly the only
Speaker 1: other alternative UM. However, one of the limiting factors here
Speaker 1: is that accounts of the gear in China largely come later,
Speaker 1: from the first century CE. But he writes, quote the
Speaker 1: only earlier examples in China so far recorded, and I
Speaker 1: do want to stress this was like UM are a
Speaker 1: number of very small bronze gears and ratchets found in
Speaker 1: tombs and dating from around two b c E to
Speaker 1: fifty C. They include extraordinarily what looked like chevron or
Speaker 1: double helical gear wheels of tiny size. All seemed too
Speaker 1: small and too early to belong as has been suggested
Speaker 1: to windlasses for drawing crossbows, and we have no idea
Speaker 1: what they were for gear mystery, And I include a
Speaker 1: uh images of these uh, these mysterious gears below, So yeah,
Speaker 1: I haven't haven't had a lot of time to to
Speaker 1: investigate further to see if any additional scholarship has emerged
Speaker 1: on these little gears and what they might have been
Speaker 1: used for. Um. And I don't know if if, ultimately
Speaker 1: there are stronger arguments that have been put put forth
Speaker 1: regarding their use or possible use and crossbow technology. But
Speaker 1: it's fascinating. Oh, one of these pictures you attached. I
Speaker 1: wonder if this is what Derek J. To sell a
Speaker 1: Price was referring to when talking about ratchet shaped teeth
Speaker 1: that are twisted helickally so that they look like worms
Speaker 1: intermeshing on parallel axles. That I can see at least
Speaker 1: one of the images you include from the Chinese example
Speaker 1: could could be what he's talking about there. Yeah, that's
Speaker 1: where my mind went when you read that that debt.
Speaker 1: Having having looked at these examples, Yeah, it has kind
Speaker 1: of a worm like quality to it. Um. Now, ultimately,
Speaker 1: Lewis and his writing, he contends that gearing was either
Speaker 1: invented independently in China and in the Greek world, or
Speaker 1: that it was actually transmitted from the West to the
Speaker 1: East rather than vice versa. But but, but, like I said,
Speaker 1: that there may be additional scholarship that we just haven't
Speaker 1: come across yet regarding this, But it does raise the
Speaker 1: question what kind of gears would one be entombed with.
Speaker 1: You know, what what bit of technology would it make
Speaker 1: sense to to to go to the grave with. I mean,
Speaker 1: certainly a very nice crossbow seems like the sort of
Speaker 1: thing you might bring with you. Um, I don't know
Speaker 1: if it would make sense for there to be some
Speaker 1: sort of like purely novelty gear device, like something that
Speaker 1: was more of a curio that maybe wasn't fully utilized,
Speaker 1: or you know, an analog computer. Yeah, it could be.
Speaker 1: I guess if your journey in the afterlife really depends
Speaker 1: on knowing when an eclipse is coming, yeah, I wonder yeah, yeah,
Speaker 1: And then of course, but then of course, just interlocking
Speaker 1: gears and turning things are just are interesting. They they
Speaker 1: they make us think about about motion and uh, interlocking energy.
Speaker 1: So I don't know, it seems like they're they're a
Speaker 1: few different directions it could go in that I could
Speaker 1: I could imagine somebody saying, uh, that is something I
Speaker 1: want to be buried than now. I want to come
Speaker 1: back to the concept of gears in biology because for
Speaker 1: a long time. While there was probably no known example
Speaker 1: of a working gear in the in the biological world,
Speaker 1: there have been observations before of animals having appendages certainly
Speaker 1: look like toothed gears. And my favorite, uh instance I
Speaker 1: came across here is a creature called the wheel bug
Speaker 1: or Aeralists cristatus. This is a type of predatory assassin
Speaker 1: bug that preys on all kinds of insects, including a fids, caterpillars, beetles,
Speaker 1: and bees. I found some very gnarly looking images of
Speaker 1: of caterpillar mutilation. Yeah, I don't think i'd really seen
Speaker 1: this species before, these creatures before, but yeah, they're quite
Speaker 1: cool looking. It kind of looks like it has some
Speaker 1: sort of a gear emerging from its back. Also, it
Speaker 1: reminds me of a buzz saw or perhaps to some
Speaker 1: degree of something like a stegasuris or or or demetrodon
Speaker 1: or something. Yeah. So it's called the wheelbug, but I
Speaker 1: think maybe a better name would be the gear bug,
Speaker 1: because it really does look like it's it's got this
Speaker 1: toothed gear poking up out of the back of its
Speaker 1: carapace right sort of behind where the head is up
Speaker 1: on the thorax and so I was reading about this
Speaker 1: insect on the University of Florida Department of in Toropology's website.
Speaker 1: They've got a good profile on it there, and they
Speaker 1: say in adulthood, this insect tends to measure about one
Speaker 1: to one and a quarter inches long, and then quote,
Speaker 1: this assassin bug is a dark, robust creature with long
Speaker 1: legs and antinnie, a stout beak, large eyes on, a
Speaker 1: slim head, and a prominent thoracic semi a circular crest
Speaker 1: that resembles a cog wheel or a chicken's comb. This
Speaker 1: is the only insects species in the United States with
Speaker 1: such a crest. The number of teeth or tubercles in
Speaker 1: the crest varies from eight to twelve. Now immediately you're
Speaker 1: you're probably wondering, as I was, what does it do?
Speaker 1: What what is the gear on its back do? I
Speaker 1: could not find any solid research alluding to a purpose
Speaker 1: of this cog wheel crest. That there may be something
Speaker 1: out there that I couldn't come across, or it may
Speaker 1: just be unknown. I think it's more likely unknown at
Speaker 1: this point what this gear crest is for, in which case,
Speaker 1: barring other knowledge, I guess you might assume that this
Speaker 1: purpose might have something to do with appearance rather than
Speaker 1: any mechanical function. Maybe it plays a visual role in
Speaker 1: interactions with predators or prey or mates, or maybe it's
Speaker 1: a defensive somehow. It's hard to tell um but apparently.
Speaker 1: Another interesting fact is that the wheel is absent in
Speaker 1: juvenile so if you look at nymphs of this assassin bug,
Speaker 1: they don't have it. It only appears in adults after
Speaker 1: the insects final molting, so once it reaches its ultimate form,
Speaker 1: then it's got the gear. But whatever it's for, it
Speaker 1: does not appear to be a functional gear. It just
Speaker 1: looks like one. I mean, for one thing, it can't rotate,
Speaker 1: and there's nothing really that it could clearly be rotating
Speaker 1: against locking its teeth with. It's just a crest that
Speaker 1: kind of looks like a gear or like a like
Speaker 1: a chicken's comb. Now, as amazing as these insects look,
Speaker 1: one thing I should probably note is that you don't
Speaker 1: want to try to handle it, because apparently wheelbugs can
Speaker 1: produce an extremely painful bite that that lingers for days.
Speaker 1: But but anyway, this animal is worth looking up. There
Speaker 1: are actually a few other interesting things about them. For
Speaker 1: one thing, they do appear to practice some amount of
Speaker 1: sexual cannibalism. Also they there is another mystery about them
Speaker 1: where they produce a vocalization. I think they create a
Speaker 1: chirping sound by a certain type of a friction mechanism
Speaker 1: where they rub one part of their body on another.
Speaker 1: I think maybe they're rubbing some uh they're either their
Speaker 1: beak or four legs. I think it was the beak
Speaker 1: on an on a part on the underside of their
Speaker 1: carapacet and it creates this chirping And scientists, as far
Speaker 1: as I could tell, don't know what this is for yet.
Speaker 1: But coming back to the idea of an actual mechanically
Speaker 1: functional gear in biology, as of a study published in
Speaker 1: the year in the journal Science, there actually is at
Speaker 1: least one known animal that does contain working toothed gears
Speaker 1: within its body, and as far as I could tell,
Speaker 1: this is also still the only animal that has this
Speaker 1: feature that that's known, and this animal is a type
Speaker 1: of plant hopper insect known as S. S. Colliup tratis.
Speaker 1: The paper that reported the discovery of this animal gear was,
Speaker 1: like I said, published in Science in by authors Malcolm
Speaker 1: Burrows and Gregory Sutton, who both at the time worked
Speaker 1: in the biological sciences at Cambridge University, and it was
Speaker 1: called interacting gears synchronized propulsive leg movements in a jumping insect. Now, Rob,
Speaker 1: I've got some images that you can that you can
Speaker 1: look at here while I'm talking about this, there's some
Speaker 1: really interesting electron micrographs of of these these gear pieces.
Speaker 1: They truly don't really look animal, right, you know, they
Speaker 1: do look like a machine. And I always love that
Speaker 1: when you like zoom way in on the parts of
Speaker 1: an insect or something and you get that hr Geeger
Speaker 1: space where you can't tell if what you're looking at
Speaker 1: is is natural or artificial. Yeah, because there's one image
Speaker 1: here of believe a nymph um of of this uh,
Speaker 1: of this species, and you know it's it's cute, but
Speaker 1: it doesn't really look like anything other than some sort
Speaker 1: of a fly or insect um. But yeah, when you
Speaker 1: start looking at these these electron microscope images, yeah, then
Speaker 1: then it takes on this bio mechanical kind of reality
Speaker 1: and it's yeah, it's quite unlike anything else. It's so,
Speaker 1: what is this animal, the the s s. Coleopterus, Well,
Speaker 1: this is an insect that is again known as a
Speaker 1: plant hopper. I think you'll normally find them crawling around
Speaker 1: on bits of ivy in Europe and North Africa, and
Speaker 1: so they're they're very very small. They're usually just about
Speaker 1: three millimeters long at maturity um, and so they'll go
Speaker 1: around grazing on ivy leaves. And the discovery that's announced
Speaker 1: in this report is that the juveniles of this species,
Speaker 1: so not the adults, but the nymphs. The juveniles, they
Speaker 1: have these interlocking gear teeth on their back legs which
Speaker 1: allow them to rotate their legs in perfect synchronization when
Speaker 1: they are setting up a jump. So these tiny insects
Speaker 1: have have their main defense against predators. And it's not
Speaker 1: clear exactly what predator this is most adapted against, So
Speaker 1: I don't know if this would be you know, against
Speaker 1: the possibility of being eaten by a large man hold
Speaker 1: that's grazing on foliage, or being pounced on by a
Speaker 1: parasitic wasp or some other kind of smaller insect predator
Speaker 1: or spider or something that's not quite known for sure,
Speaker 1: but but there it is probably some kind of survival
Speaker 1: defensive adaptation that this creature needs to be able to
Speaker 1: jump far and jump fast, and they are one of
Speaker 1: the most amazing jumpers in all of nature. I was
Speaker 1: watching an interview with one of the authors of the study,
Speaker 1: Malcolm Burrows, in which he talks about the jumping mechanism,
Speaker 1: and so the s S insect will take off at
Speaker 1: a at a jump of about five meters per second
Speaker 1: or more than eight miles per hour, which for a
Speaker 1: tiny insect like this is pretty fast. It accelerates to
Speaker 1: its jumping speed in less than a millisecond. And so
Speaker 1: the way Burrows explain this is that this insect experiences
Speaker 1: absolutely unfathomable G forces as it takes off because it's
Speaker 1: acceleration is so fast. He puts it at five hundred
Speaker 1: or even seven hundred g s, which if you look
Speaker 1: at the amount of g's that humans are able to tolerate,
Speaker 1: it's like the amount you can tolerate is a factor
Speaker 1: of how long you are subjected to them. But you know,
Speaker 1: usually for humans, the the the acceleration we can tolerate
Speaker 1: in gs, the maximum is like a factor of a
Speaker 1: few tens, you know, but this would be hundreds. Yeah,
Speaker 1: this is impressive. So this insect has this amazingly fast,
Speaker 1: amazingly powerful jump that can just catapult. It's like it's
Speaker 1: shooting itself out of a cannon using the power of
Speaker 1: its two hind legs. And what was documented in this
Speaker 1: paper by by Burrows and Sutton is that they they
Speaker 1: captured imagery of gear mechanisms on the hind legs interlocking
Speaker 1: using electron microscopy and high speed video recording UH and
Speaker 1: and again the purpose that they found is that these
Speaker 1: UH interlocking gear teeth are useful for synchronizing the motion
Speaker 1: of the legs. Now, why would synchronization of the leg
Speaker 1: movement be so important that it would have its own
Speaker 1: evolved mechanism, which is, as far as we know, unique
Speaker 1: in the animal kingdom. Well, apparently it's because coordination of
Speaker 1: the timing on the two legs is necessary for this
Speaker 1: incredibly powerful sort of cannon shot jump to be effective.
Speaker 1: So I was reading about this in one of the
Speaker 1: press releases about the about the study, and what the
Speaker 1: author's here found is that a lack of synchronization between
Speaker 1: the legs at launch could cause an uncontrolled what they
Speaker 1: call yaw rotation. So if you if you picture an airplane,
Speaker 1: you know you've got the different uh, the different ways
Speaker 1: that you can change the motion of the airplane. You've
Speaker 1: got pitch role and yaw, So pitch would be tipping
Speaker 1: the nose of the airplane up or down. Role would
Speaker 1: be raising, that would be roll ling the airplane, you know,
Speaker 1: raising the wings relative to each other, and then yaw
Speaker 1: is twisting side to side. If you can imagine an
Speaker 1: insect that's sort of catapulting itself in this spectacular jump
Speaker 1: with two with pushing off with the two hind legs
Speaker 1: at the same time, if one leg pushes off faster
Speaker 1: than the other one, you can imagine that it's going
Speaker 1: to send the insects sort of twisting out of control
Speaker 1: in its path, which obviously interferes with landing where it's
Speaker 1: trying to land now, one question would be why the
Speaker 1: need for a mechanical gear for synchronization? What why does
Speaker 1: this need to be on the insects exoskeleton. Why wouldn't
Speaker 1: the insect just synchronize the action of its legs through
Speaker 1: the nervous system like pretty much any other animal would, right,
Speaker 1: Like if you are jumping, you are able to synchronize
Speaker 1: the motion of your legs through neural mechanisms with your
Speaker 1: brain and your nervous system sort of trying to control
Speaker 1: them through normal motor function, and then getting feedback from
Speaker 1: the feelings of your legs from like your appropriate reception
Speaker 1: and stuff and tactle sensations to to try to time
Speaker 1: the jump together and correct for any imbalances in real time. Well,
Speaker 1: apparently the insect can't do that because the problem is
Speaker 1: it's jump is too fast to synchronize through the nervous system.
Speaker 1: The acceleration leading into the jump happens so quickly that
Speaker 1: the nervous system cannot do real time feedback to coordinate it.
Speaker 1: So it needs this mechanical lock on the legs themselves
Speaker 1: to make sure synchronization is happening, because the insects nervous
Speaker 1: system can't talk to itself fast enough to make sure
Speaker 1: that the that the jump is on target. In their
Speaker 1: In their press release, author Malcolm Burrows summarized it like
Speaker 1: this quote. The precise synchronization would be impossible to achieve
Speaker 1: through a nervous system, as neural impulses would take far
Speaker 1: too long for the extraordinarily tight coordination required by developing
Speaker 1: mechanical gears. The s s can just send nerve signals
Speaker 1: to its muscles to produce roughly the same amount of force.
Speaker 1: Then if one leg starts to propel the jump, the
Speaker 1: gears will interlock, creating absolute synchronicity and ss. The skeleton
Speaker 1: is used to solve a complex problem that the brain
Speaker 1: and nervous system can't This emphasizes the importance of considering
Speaker 1: the properties of the skeleton in how movement is produced.
Speaker 1: And this was really interesting to me because it also
Speaker 1: comes back to you could maybe even consider this a
Speaker 1: case of sort of supplementing the cognitive abilities of the
Speaker 1: nervous system, sort of embodied cognition, allowing the body to
Speaker 1: do math for you that your brain and nervous system
Speaker 1: can't handle. Yeah, because essentially it's a it's it's a
Speaker 1: physical way of solving a problem that is beyond cognitive ability,
Speaker 1: um and and and and really when we're talking about
Speaker 1: the g forces pulled here and think this is beyond
Speaker 1: base flights. So when we talk about like humans have
Speaker 1: not evolved to travel in space or to deal with
Speaker 1: certain speeds or or physical realities, like this is a
Speaker 1: case here where I mean this this creature is is
Speaker 1: essentially engaging in those kinds of speeds, those kinds of
Speaker 1: rapid accelerations. Uh So, it's yeah, it's fascinating to think
Speaker 1: about here. Yeah, the body moves too fast for the
Speaker 1: nervous system to make sense of, so it just offloads that.
Speaker 1: That computation that the motor parts of the nervous system
Speaker 1: might do naturally, offloads that onto the skeleton. Now, the
Speaker 1: exoskeleton of the insect is doing the math for you,
Speaker 1: kind of like an analog computer would like the antiqua
Speaker 1: theorem mechanism. Wow. Wow. So to take a slightly closer
Speaker 1: look at these teeth, at the gears on the hind legs.
Speaker 1: They're located on the backs of the strong hind legs
Speaker 1: that the s s insect uses to jump um there
Speaker 1: on the parts of the legs known as the trocantera
Speaker 1: and it's actually a human skeleton has rocantera to they're
Speaker 1: they're sort of on the upper part of the femur,
Speaker 1: near where the femur would would connect to the pelvis.
Speaker 1: And these these insects tend to have somewhere between ten
Speaker 1: to twelve teeth on their gears. But while it seems
Speaker 1: to vary between the insects, the insect always has the
Speaker 1: same amount of teeth on each side within itself. Each
Speaker 1: tooth is about eighty micrometers wide, so eighty millionths of
Speaker 1: a meter. And there are some interesting engineered features of
Speaker 1: of these gear teeth within the body that have been
Speaker 1: created by the evolutionary process that gives rise to them. Here,
Speaker 1: the teeth have rounded corners at the point of contact,
Speaker 1: and this is useful apparently because it would help prevent
Speaker 1: the gears from being sheared off or broken off if
Speaker 1: there is a slight misalignment during a jump. And then
Speaker 1: another interesting thing about them is that they are differently
Speaker 1: shaped than most gears we use in the technological world,
Speaker 1: because usually gears made by humans tend to have symmetrical teeth, right,
Speaker 1: you know, there's sort of curved straight out from the
Speaker 1: gear strip surface, but in these the teeth are not
Speaker 1: quite symmetrical. They're sort of angled out. And it's because
Speaker 1: this gear only needs to work one way, so like
Speaker 1: after the launch is done, the gear teeth can just
Speaker 1: separate from each other and they don't need to roll
Speaker 1: backwards in in the direction opposite from which they came.
Speaker 1: It's a one way gear. Yeah, and you definitely get
Speaker 1: that from looking at the image. It feels like some
Speaker 1: sort of a biomechanical um, you know, firing mechanism, right,
Speaker 1: A firing mechanism is a is a good way to
Speaker 1: compare it, because again, it doesn't go both ways and
Speaker 1: it doesn't need to roll all the way around. It's
Speaker 1: just sort of a strip of interlocking teeth that doesn't
Speaker 1: complete a full circle. And it only and it only
Speaker 1: rolls one way only on launch. Yeah, Like it kind
Speaker 1: of looks like if hr gear designed a flint lock.
Speaker 1: Uh yeah, or maybe if David Cronenberg did you know, yeah, oh,
Speaker 1: but so there was a really interesting thing about the research,
Speaker 1: the question of how did they figure out that these
Speaker 1: gear teeth locked for synchronization while launching the jump? Right? Like,
Speaker 1: how how did they observe that? Well, apparently the authors
Speaker 1: here used a dead insect. They used an insect corpse.
Speaker 1: And what they did was they they took the dead
Speaker 1: insects legs and rotated them back into the jump launching position.
Speaker 1: And then the researchers used an electrical stimulus to cause
Speaker 1: a contraction in the jumping muscle of only one of
Speaker 1: the legs. Okay, so they they stimulate only one leg
Speaker 1: as if it has been told by the brain to jump.
Speaker 1: But because the gear teeth were locked. When the legs
Speaker 1: were in jump readying position, the insects legs both performed
Speaker 1: the launching motion, even the dead leg on the other
Speaker 1: side that had not been electrically stimulated, and the insect
Speaker 1: leapt straightforward, so you could stimulate only one of the
Speaker 1: two legs, kind of like how an airplane can fly
Speaker 1: with only one engine. You know, you only need to
Speaker 1: stimulate one of the legs, and the gears keep both
Speaker 1: legs locked in sync. Now there's another interesting question here,
Speaker 1: why only the juveniles I think I already mentioned that
Speaker 1: the adult insects don't have these interlocking gear teeth. They've
Speaker 1: got a feature that's more common, more like what you'd
Speaker 1: see in a lot of other jumping insects, which is
Speaker 1: not gear teeth, but just sort of um bumps or
Speaker 1: friction pads, so their back legs might touch each other
Speaker 1: and and the touching their helps keep the jump synchronized.
Speaker 1: But they don't actually have interlocking teeth. It's more just
Speaker 1: kind of like pushing to surfaces together that grip each
Speaker 1: other pretty well. In another study by Burrows, he noted
Speaker 1: that this is achieved by quote mechanical actions between small
Speaker 1: protrusions from each trochantera, which fluoresce bright blue under specific
Speaker 1: wavelengths of ultraviolet light and which touch at the midline
Speaker 1: when the legs are cocked before a jump. So they
Speaker 1: adults are touching parts of their back legs together to
Speaker 1: help synchronize a jump, but they don't have gear teeth.
Speaker 1: And the hypothesized explanation for the difference here is that
Speaker 1: is this Insects go through periods of molting as they grow. Right,
Speaker 1: So an insect, as it gets bigger and bigger, it
Speaker 1: will shed its old hard exoskeleton and then it will
Speaker 1: grow bigger and allow a new exoskeleton to harden. But
Speaker 1: the adult exoskeleton at full maturity, it lacks these interlocking
Speaker 1: gear teeth. And the idea is maybe the adults don't
Speaker 1: have the teeth because if the teeth on the jumping
Speaker 1: mechanism were to break or get sheared off but by error,
Speaker 1: this would sort of break their ability to jump. And
Speaker 1: so once the adult is in full molted form and
Speaker 1: it's not going to shed its exoskeleton again, it needs
Speaker 1: to have a less fragile mechanism. But the younger's, the
Speaker 1: younger ones the juveniles, because they will go through multiple
Speaker 1: moltings and can grow new gear teeth if they're old
Speaker 1: gear teeth break, they pay less of a price for
Speaker 1: having this somewhat fragile mechanism. Okay, so here we see
Speaker 1: sort of in in their early stages the advantages of
Speaker 1: having an an exoskeleton, and then in in later life
Speaker 1: the disadvantages of having an exo skeleton, and that you're
Speaker 1: not going to get another one, right, And so when
Speaker 1: you're not going to get another one, it makes more
Speaker 1: sense for evolution to supply you with more durable mechanisms
Speaker 1: that aren't going to possibly like kill you if if
Speaker 1: they break, right, there would be a survival advantage in
Speaker 1: having a jumping mechanism that's not going to it's not
Speaker 1: going to be like a Boba Fett's uh jet pack
Speaker 1: firing off at a weird angle and sending you into
Speaker 1: the sarlac. Right, But that's just a hypothesized explanation for
Speaker 1: the difference between the juveniles and adults. Ultimately, we don't
Speaker 1: know for sure there and as far as I can tell,
Speaker 1: this is still the only known tooth to gear in
Speaker 1: the animal kingdom. That there may have been something since
Speaker 1: then that I wasn't able to track down, but looks
Speaker 1: like this is still the only one. Yeah, well, this
Speaker 1: is fascinating. It kind of brings me back to the
Speaker 1: biobmetics question earlier. You know, um in evolution solving particular
Speaker 1: engineering problems over time, and this is an example where
Speaker 1: the the engineering problem is extreme enough that and the
Speaker 1: and the circumstances of its its lifespan enable the sort
Speaker 1: of answer to evolve and take place. Yeah. Yeah, can
Speaker 1: you imagine if you had gear teeth on your inner
Speaker 1: thighs that helps you jump? It seems uncomfortable. Yeah, yeah,
Speaker 1: I'd have to have an exoskeleton too for this place.
Speaker 1: Or yeah, I'd have to have some other kind of
Speaker 1: weird arrangement, like you would have to be bone spurs
Speaker 1: or keith that grow back, I guess, because that would
Speaker 1: again you'd have to have the situation of what what
Speaker 1: do you do about the wear and tear of this
Speaker 1: the physical mechanics here, I mean, it doesn't really make
Speaker 1: sense for our bodies because that wouldn't that wouldn't be
Speaker 1: how we jump anyway, or like I need to work
Speaker 1: differently for that to make sense. Yeah. Yeah, So again
Speaker 1: we come down to a very specific evolved answer to
Speaker 1: a specific problem that yeah, you're just not going to
Speaker 1: see in in in other organisms. But I am still
Speaker 1: in memorative the idea that in a way, these these
Speaker 1: gear teeth on the insects legs are a kind of computer.
Speaker 1: They're doing a kind of mathematical processing for the animal.
Speaker 1: This is the this is the computer of the thighs. Yeah.
Speaker 1: And and also it's interesting too that no matter how
Speaker 1: no matter how much you know, humanity clung to the
Speaker 1: wheel and to gears and and saw this as their
Speaker 1: technological achievement. Here we have an example of evolution once more,
Speaker 1: beating humanity to the punch. Uh. So, well, before the
Speaker 1: Greeks of Alexandria were devising their uh their gear you
Speaker 1: know complexities. Uh, this creature already had the gears right
Speaker 1: there in its thighs. These gears are hopping. Yeah. Well
Speaker 1: this was fun. I enjoyed talking about everything from we
Speaker 1: had a little bit of an invention episode owed uh
Speaker 1: in here we had some biology, we had a little
Speaker 1: bit of mythology and folklore, so it would be interesting
Speaker 1: to come back to this and and we talked about
Speaker 1: potentially covering screws and screws in nature in this episode,
Speaker 1: but perhaps that would make for its own future episode.
Speaker 1: Oh yeah, there are actually a few things in nature
Speaker 1: that you could argue or screws. Yeah, and then and
Speaker 1: and of course the invention of the screw and uh
Speaker 1: and so forth is also quite interesting. All Right, we're
Speaker 1: gonna go and close it up then, but we'd love
Speaker 1: to hear from everyone out there. Um certainly reach out
Speaker 1: to us, get in touch with us. In the meantime,
Speaker 1: if you want to check out other episodes of Stuff
Speaker 1: to Blow Your Mind Core episodes publishing the Stuff to
Speaker 1: Blow Your Mind podcast feed on Tuesdays and Thursdays, sandwich
Speaker 1: between them, we have an Artifact episode or for the
Speaker 1: months of September and October. Anyway, it's going to be
Speaker 1: the Monster Fact. It's gonna we're gonna take on more
Speaker 1: of a monstrous form for the holidays here and then
Speaker 1: it will likely revert back to the Artifact. We have
Speaker 1: listener mail on Mondays. We have a little Weird House
Speaker 1: in them on Friday, so that's our time just to
Speaker 1: discuss a weird film, and then we have a rerun
Speaker 1: over the weekend. Huge thanks as always to our excellent
Speaker 1: audio producer Seth Nicholas Johnson. If you would like to
Speaker 1: get in touch with us with feedback on this episode
Speaker 1: or any other suggest topic for the future, just to
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