Speaker 1: Hey, you welcome to Stuff to Blow your Mind. My
Speaker 1: name is Robert Lamb, and today is Saturday. Once more,
Speaker 1: so we have an episode from the vault. This is
Speaker 1: going to be Odds and Evens, Part three, and it
Speaker 1: originally published nine to twelve, twenty twenty four. Enjoy Welcome
Speaker 1: to Stuff to Blow Your Mind, production of iHeartRadio. Hey,
Speaker 1: welcome to Stuff to Blow your Mind.
Speaker 2: My name is Robert Lamb and I am Joe McCormick,
Speaker 2: and we are back for the third and final part
Speaker 2: in our series on the psychology and cultural significance of
Speaker 2: number paroity pr it y parody referring to whether a
Speaker 2: number is even or odd, and we are ending it
Speaker 2: with an odd number of episodes that just felt right now.
Speaker 2: If you haven't heard the other parts in this series,
Speaker 2: you might want to go back in list into those first.
Speaker 2: But in part one we talked about the mathematical principle
Speaker 2: of number parity, as well as some evidence that people,
Speaker 2: if given the opportunity, will sometimes project associations and emotions
Speaker 2: onto even and odd numbers, for example, by maybe feeling
Speaker 2: more positivity toward even numbers on average, or by having
Speaker 2: an esthetic preference for odd numbers in visual art, as
Speaker 2: reflected in the conventional rule of thirds and rule of
Speaker 2: odds in art theory, which we discussed in some detail
Speaker 2: in that episode. But then we also brought in some
Speaker 2: questions and counter evidence about the real world validity and
Speaker 2: alleged universality of these preferences for odds in art. In
Speaker 2: part two of the series, we talked about a research
Speaker 2: paper on the cognitive psychology of number parity, which advanced
Speaker 2: what I thought was a really interesting argument that despite
Speaker 2: the fact that all positive integers are mathematically defined as
Speaker 2: simply odd or even and nothing in between, our brains
Speaker 2: may in practice treat some numbers as more even or
Speaker 2: more odd than others, mentally transforming these definitionally discrete categories
Speaker 2: into a semi smooth gradient. And this could be due
Speaker 2: to multiple factors, involving mathematical properties like the ease of divisibility,
Speaker 2: and also linguistic properties about how easily we process different
Speaker 2: words and their associated concepts. We also talk some more
Speaker 2: about even and odd groupings in visual art, specifically in
Speaker 2: religious images such as that of the ten headed demon
Speaker 2: king Ravina in Hindu mythology, and we also talked about
Speaker 2: preferences for even or odd groupings on food plates. I
Speaker 2: think the conventional wisdom favors odd numbers of food items,
Speaker 2: but the research maybe paints a slightly more complicated picture.
Speaker 1: Yeah, I think in either case, what does what does
Speaker 1: a plate of food and the multi headed incarnation of
Speaker 1: a Hindu god? What do they have in common? It's
Speaker 1: that there are other things involved and how you're ultimately
Speaker 1: going to perceive this image. Either religious iconography is going
Speaker 1: to be trying to relate other concepts to you the viewer,
Speaker 1: the intended audience viewer, and the food imagery is of
Speaker 1: course showing you something that on some level at least
Speaker 1: you want to eat.
Speaker 2: Yeah, exactly. So we're here today to finish off this
Speaker 2: series with a few more things about odd and even topics.
Speaker 2: So I just wanted to mention at the top of
Speaker 2: the episode here a few more interesting ideas I came
Speaker 2: across while reading about events and odds. Previously, we talked
Speaker 2: about some evidence that at least in certain contexts, people
Speaker 2: like some numbers more than others. For example, they may
Speaker 2: have more positive emotional feelings about even numbers, or at
Speaker 2: least about numbers that are easily divisible because one of
Speaker 2: the studies we talked about in Part one apparently found
Speaker 2: that people had more positive feelings toward even numbers and
Speaker 2: numbers to visible five. Coming back to the question of
Speaker 2: certain numbers feeling more even or less odd than they
Speaker 2: really are. So a great example is that twenty five
Speaker 2: is an odd number, but why does it feel like
Speaker 2: an even number? To me? I would say the ease
Speaker 2: of divisibility by the sub base of five is a
Speaker 2: pretty good guess. And this sort of brings me back
Speaker 2: to an idea I first encountered in a couple of
Speaker 2: the articles that we were talking about in Part one
Speaker 2: by a British author named Alex Bellows who writes newspaper
Speaker 2: columns about mathematics and puzzles sometimes, but it also written
Speaker 2: a book addressing some of these topics. And in these
Speaker 2: articles he talked about people's feelings about odd and even numbers,
Speaker 2: and the idea he raises that if it's true that
Speaker 2: people sometimes feel better about even numbers than odd ones,
Speaker 2: what if that sense of liking for even numbers is
Speaker 2: related to the concept of processing fluency. Now, this is
Speaker 2: a psychological concept that has come up the show before.
Speaker 2: The gist of the idea is that a lot of
Speaker 2: the judgments that humans make, from whether we like something
Speaker 2: to whether we trust a piece of information or believe
Speaker 2: something is true, a lot of these judgments are influenced
Speaker 2: by our subconscious reaction to how easy it is for
Speaker 2: us to mentally process the stimulus in question. There are
Speaker 2: a lot of studies looking at this. I remember this
Speaker 2: came up when we were discussing the illusory truth effect,
Speaker 2: the idea that if a claim a claim may have
Speaker 2: no real evidence for it, or you may have no
Speaker 2: particular reason for believing a claim is true, but if
Speaker 2: you hear it repeated a bunch of times, it starts
Speaker 2: to feel more and more true to you. And one
Speaker 2: of the popular explanations for this effect is the idea
Speaker 2: that hearing a hearing a claim on subsequent exposures increases
Speaker 2: its process in fluency because it's more a miliar to you.
Speaker 2: You've heard it before, so it's easier to take in
Speaker 2: the second, third, fourth, fifth time you hear it, and
Speaker 2: thus it because it has increased processing fluency, it just
Speaker 2: feels more right, It feels more true. One of the
Speaker 2: key findings that already came up in some of the
Speaker 2: papers we talked about in Part two is that it
Speaker 2: seems even numbers are on average more easily processed than
Speaker 2: odd numbers are. You know, when it's easier to think
Speaker 2: about even numbers, we can more quickly classify them mathematically
Speaker 2: as even numbers, it's easier to think about doing mathematical
Speaker 2: operations with them. Odd numbers are just they're introducing friction
Speaker 2: to your brain when you have to consider them. And
Speaker 2: if this is the case, it could be a major
Speaker 2: contributor to these particular situations where people seem to like
Speaker 2: even numbers better than odd numbers. But of course we
Speaker 2: don't always like even numbers better than odd numbers. And
Speaker 2: this comes back to the issues of these additional bits
Speaker 2: of context and cultural associations happen to pin onto these numbers,
Speaker 2: and whether at the time of us having a feeling
Speaker 2: about a number or making a judgment about it, these
Speaker 2: other associations become salient. So anyway, that brings me to
Speaker 2: another line of research that I stumbled across when looking
Speaker 2: into this, that I thought was curious and sort of
Speaker 2: funny also, which is the apparent association between number parity
Speaker 2: and the social concept of gender. Now in much the
Speaker 2: same way, it seems absurd that without any context, in
Speaker 2: other words, without quantifying anything in particular, specific numbers whatever
Speaker 2: feel good or bad to people. It also seems kind
Speaker 2: of absurd that anyone would think of standard Arabic numerals
Speaker 2: as masculine or feminine. But there are some experiments in
Speaker 2: which researchers claim to have found that in some contexts
Speaker 2: there is a pattern of gendered associations between odd and
Speaker 2: even numbers that emerge.
Speaker 1: This is interesting because I I was thinking about gender
Speaker 1: numbers earlier in the research process for this series, because
Speaker 1: I ran across an interesting skit about the number one
Speaker 1: on Sesame Street.
Speaker 2: Oh care to elaborate?
Speaker 1: Oh sure, sure, So in this sketch, this is from
Speaker 1: nineteen ninety seven, so this is not one that I
Speaker 1: was originally exposed to as a kid. But we have
Speaker 1: number one, which is of course a muppet. It is
Speaker 1: the numeral one, and it is a she. So the
Speaker 1: number one she is feeling really down about herself because
Speaker 1: she is such a low value number, like you know,
Speaker 1: it's just she's it's one and then zero, like all
Speaker 1: the other numbers are more potent than her, more important
Speaker 1: than her, and she feels she's really feeling down in
Speaker 1: the dumps about it. Well, who comes up to cheer
Speaker 1: her up? But the Count? Oh, And the Count proceeds
Speaker 1: to sing an entire song for her about how important
Speaker 1: she is numerically, and then afterwards he's like, do you
Speaker 1: feel better? And she's like, well a little bit, and
Speaker 1: he says, well, I'm going to sing it for you
Speaker 1: one more time. But it got me think. It's like, well,
Speaker 1: you know, I didn't think about one being male female,
Speaker 1: what have you? I didn't think about the gender of
Speaker 1: the number one. I just considered it like a number.
Speaker 1: But now I'm thinking of it. I just can't help
Speaker 1: but picture it with like the big full lips and
Speaker 1: the beauty mark here from this nineteen ninety seven Sesame
Speaker 1: Street sketch.
Speaker 2: Well, that is adorable. I like the Count. I hope
Speaker 2: that the Count can help any number feel better about itself.
Speaker 2: All numbers are important, but one is really special.
Speaker 1: Yeah. I think the Count is going to be the
Speaker 1: biggest fan, the biggest supporter of any number. He's not
Speaker 1: going to pull a Harry Neilson and talk about how
Speaker 1: crappy the number one is and how number two is
Speaker 1: also no good. He's a big fan of all of them.
Speaker 2: I like knowing you can count on the count for
Speaker 2: emotional support, so anyway to mention A couple of these
Speaker 2: studies apparently finding this association between gender and number parody.
Speaker 2: A couple of the ones I came across were by
Speaker 2: a pair of researchers named Wilkie and Bodenhausen. One of
Speaker 2: these papers was from twenty twelve in the Journal of
Speaker 2: Experimental Psychology, another one by the same authors from twenty
Speaker 2: fifteen in Frontiers in Psychology, and these papers published the
Speaker 2: results of a number of different experiments about the gender
Speaker 2: associations of odd and even numbers. Now, some of these
Speaker 2: experiments involved explicit judgments, just asking people straight up whether
Speaker 2: they felt like specific numbers were more masculine or feminine,
Speaker 2: and other experiments looked for indirect associations, like people's tendency
Speaker 2: to interpret the faces of babies or unfamiliar foreign names
Speaker 2: with different genders when they were labeled with different numbers.
Speaker 2: And to note that this indirect measure here does rely
Speaker 2: on implicit association tests, which have been subjected to various
Speaker 2: methodological critiques over the years. They've undergone some refinements over
Speaker 2: time to try to improve reliability. But there's still sort
Speaker 2: of debates about how they can be depended on and
Speaker 2: in what context. So anyway, caution on relying too much
Speaker 2: on the implicit parts of these findings. But the authors
Speaker 2: say from the totality of their experiments that on average,
Speaker 2: for some reason, people from sample groups within the United
Speaker 2: States are more likely to say that odd numbers are
Speaker 2: masculine and even numbers are feminine. And while that's the
Speaker 2: general trend, there are some exceptions and caveats. While they
Speaker 2: say that this pattern was on average true for everyone,
Speaker 2: the association was stronger among women, So on average, women
Speaker 2: were more likely to view odd numbers as more masculine
Speaker 2: and less feminine than even numbers. Weirdly, this is where
Speaker 2: it starts getting funny. I thought the numbers in when
Speaker 2: the numbers involved were two digit instead of one digit,
Speaker 2: men started to drift away from this parody association and
Speaker 2: started to say that all numbers were masculine, regardless of parody.
Speaker 2: So I don't whenever we look at studies like this,
Speaker 2: By the way, I always like raise caution because I
Speaker 2: just know from experience a lot of people get real
Speaker 2: excited about like gender differences in responses to psychological experiments
Speaker 2: and then start overinterpreting, thinking it explains everything about men
Speaker 2: and women. Oh, you know why my husband or my
Speaker 2: wife acts a certain way, et cetera. And so I
Speaker 2: will raise the same caution here. You know, it's just
Speaker 2: a few experiments. We're not sure if this is a
Speaker 2: super robust finding, and even if it is robust, it's
Speaker 2: easy to get carried away just reading too much into
Speaker 2: little psychological quirks like this. However, I could not resist
Speaker 2: finding it hilarious to imagine a guy looking at numbers
Speaker 2: higher than nine and being like, thirty four. Huh, that's
Speaker 2: a big number. That's a macho man.
Speaker 1: In between thoughts about ancient real right.
Speaker 2: Yeah, so in reality it's probably not that simple, but
Speaker 2: I was laughing for several minutes after I read this. Anyway,
Speaker 2: the authors of these studies, so they're making an argument
Speaker 2: not that there actually is something objectively or universally gendered
Speaker 2: about even and odd numbers, and instead they're sort of
Speaker 2: making a case about what they call, quote, the pervasiveness
Speaker 2: of gender as a social scaffolding for generating understandings of
Speaker 2: abstract concepts. So the way I take that is they're
Speaker 2: sort of saying gender is such an important concept to
Speaker 2: people that we subconsciously apply it to categories of objects
Speaker 2: that have nothing to do with the primary understanding of
Speaker 2: masculinity or femininity. It's just like a major way of
Speaker 2: making category distinctions that the brain kind of defaults to,
Speaker 2: even in situations that don't have anything to do with
Speaker 2: biological sex or with the social roles of gender.
Speaker 1: Right right, So yeah, it wouldn't be like the hypothetical
Speaker 1: male in question is making a conscious effort to think
Speaker 1: about all higher numbers as men. It's a little more
Speaker 1: new as a little more subconscious than that.
Speaker 2: Now I mentioned that those studies were done on us
Speaker 2: test subjects. I came across an interesting variation with respect
Speaker 2: to culture. So there was a twenty twenty one study
Speaker 2: in Frontiers and Psychology by Jordan Yakani and Sheen which
Speaker 2: found some consistency and some variation across cultures regarding the
Speaker 2: perceived gender of numbers. These researchers tested whether the same
Speaker 2: patterns of association between number parity and gender would show
Speaker 2: up among Arabic speaking people native to the UAE, and
Speaker 2: their top level findings were that there were patterns of
Speaker 2: gender association with number parity, but on the implicit association
Speaker 2: of numbers with faces, the subjects in the UAE were
Speaker 2: more likely to associate even numbers with their own gender,
Speaker 2: whichever that was so, men seeing even numbers as more masculine,
Speaker 2: women seeing even numbers as more feminine. And these findings
Speaker 2: indicate that it may be cross culturally common to associate
Speaker 2: even in odd numbers with gender, at least in some
Speaker 2: weekly held way, to make some kind of weak association
Speaker 2: of that kind, but that the association can vary from
Speaker 2: culture to culture, which actually makes a lot of sense
Speaker 2: to me that I think the idea would sort of
Speaker 2: be that gender is a category lens that we're very
Speaker 2: quick to apply to all kinds of phenomena outside of
Speaker 2: its primary cultural meaning, but exactly how we apply it
Speaker 2: probably depends on a lot of subtle influences that can
Speaker 2: easily vary person to person and culture to culture, though
Speaker 2: apparently within a given language culture, one way of making
Speaker 2: the association is probably more common than another. So anyway,
Speaker 2: all the warnings I gave up top about not reading
Speaker 2: too much into these kinds of findings, but I do
Speaker 2: think if this is basically on the right track, it's
Speaker 2: an interesting example of the way that we we just
Speaker 2: kind of recklessly apply category distinctions across every domain of life,
Speaker 2: whether it really makes direct sense or not. You know,
Speaker 2: I think we if we ever talked about the idea
Speaker 2: on the show before, some people seem to think like
Speaker 2: dogs or boys, cats or girls.
Speaker 1: Yeah. I have caught myself falling into that trap as well,
Speaker 1: Like I kind of on a default level assume cats
Speaker 1: are girls and dogs are boys until I know differently
Speaker 1: concerning individual cats and dogs, and I don't know. One
Speaker 1: reason for that is probably that I've only ever had cats,
Speaker 1: and those cats have always been girls. I don't know, yeah,
Speaker 1: female cats. Sorry, some of them have been very old ladies.
Speaker 2: Then again, at least cats and dogs are like animals.
Speaker 2: You know. It's I guess it's even funnier thinking about
Speaker 2: the way that we we just wantonly apply these categories,
Speaker 2: possibly even to things like abstract numbers and symbols that
Speaker 2: that don't even have like you know, bodies or minds
Speaker 2: or anything. Yeah.
Speaker 1: The only the other prime example that comes to mind
Speaker 1: is when especially a ship but sometimes other vehicles or
Speaker 1: gendered as female.
Speaker 2: Yeah, that always seemed funny to me.
Speaker 1: All right, Now for this next little bit, I wanted
Speaker 1: to talk briefly about the word odd. I was looking
Speaker 1: at other angles on odd and even, and I came
Speaker 1: across this excellent write up on Websters, and it points
Speaker 1: out that the word in English comes from the Old
Speaker 1: Norse word audie odd i, meaning point of land in
Speaker 1: the geographical sense. So it's like the point of a triangle,
Speaker 1: and so it eventually came to mean triangle, and it
Speaker 1: also came to mean odd, as the point of a
Speaker 1: triangle triangle must always oppose the two other corners, so
Speaker 1: it's like the two other corners are an even pair,
Speaker 1: and if they were to leave, then the audi is alone.
Speaker 2: Wow, that's almost poetic. That's like a beautiful etymology.
Speaker 1: Yeah. And eventually from here the term transfers over into English,
Speaker 1: and by the fourteenth century it was written down, so
Speaker 1: you know, it may have made the journey. It probably
Speaker 1: it definitely made the journey earlier than that, but that's
Speaker 1: when we have written evidence of it. And initially the
Speaker 1: word odd meant without a corresponding mate, so it was
Speaker 1: still like tied up with this idea of like to
Speaker 1: leave and leave one. But then it comes to mean
Speaker 1: irregular or non conformist, and Webster's notes that during the
Speaker 1: fifteenth and sixteenth centuries, this usage of odd in English
Speaker 1: language was a good thing. It meant you stood out,
Speaker 1: you know. It's like, oh, look at that odd character there,
Speaker 1: We've got to go chat him up. He has lots
Speaker 1: of interesting things to say as he drinketh from his
Speaker 1: skull and walketh is bear. But then by the seventeenth
Speaker 1: century it comes to lean more toward the eccentric and
Speaker 1: even dare we say, the weird, in the sense that
Speaker 1: you might be like, let's stay away from the guy
Speaker 1: with the bear and the skull. Lord knows what he's
Speaker 1: going to talk about. Let's keep a distance. Wow.
Speaker 2: It almost invokes like a story in the sense that
Speaker 2: if you imagine there were three people and two of
Speaker 2: them left, and now one is odd. Why did the
Speaker 2: other two leave? Were they driven away by the behavior
Speaker 2: of the first one? Or could they just not handle
Speaker 2: the genius?
Speaker 1: Yes, and my apologies to Lord Byron Fans, since he's
Speaker 1: barely covered in the centuries reference there. But Webster's also
Speaker 1: points out that the use of the noun odd for
Speaker 1: a point of land seems to have crossed over a
Speaker 1: second time into English during the nineteenth century, though more
Speaker 1: exclusively to northern England and Scotland. Oh and one more
Speaker 1: little bit here that I ran across. Audi is also
Speaker 1: the name of a town in Iceland. And well, I'm
Speaker 1: not as sure about the direct linguistic connection here between
Speaker 1: what we're talking about and the name of the town
Speaker 1: I did run across. The picture of a statue of
Speaker 1: Salmon the Wise hitting the Devil, and the devil may
Speaker 1: or may not be in the form of a seal
Speaker 1: here with a bible. This was I found this a
Speaker 1: photograph of this on a blog post by eric O
Speaker 1: Scott on the website The Wild Hunt. And this ties
Speaker 1: into a past episode because in our series on Shadows
Speaker 1: from last October that is going to re air this October,
Speaker 1: we talked a little bit about the shadow wizard and
Speaker 1: priest semond or Semonder, the Wise, who has various encounters
Speaker 1: with the Devil. I don't think we talked about him
Speaker 1: hitting the devil with a Bible, but there is an
Speaker 1: episode where he ends up having his shadow stolen by
Speaker 1: the devil.
Speaker 2: Right doesn't he go to like the Devil's College or
Speaker 2: the Devil's School to learn the learn the magical arts.
Speaker 2: But then the devil is supposed to grab one of
Speaker 2: the students at the end of the semester and keep them.
Speaker 2: But semen, they're various tellings, but semen find some way
Speaker 2: to kind of trick the devil and escape.
Speaker 1: Yeah. Yeah, and he like goes to snatch his soul
Speaker 1: and gets his shadow instead and so forth. So I
Speaker 1: don't know, I'm drifting drifting off topic here, but we're
Speaker 1: still somewhere in the neighborhood of a lot and even now. Next,
Speaker 1: I would like to turn to evens and odds and biology.
Speaker 1: This is an area that, uh where you can you know,
Speaker 1: I guess with any of this you have to, especially
Speaker 1: when you're playing in to biology, you have to think
Speaker 1: about like the relationship between numbers and reality, and you
Speaker 1: can get, you know, kind of go do a fair
Speaker 1: amount of navel gazing on that in and of itself.
Speaker 1: But you know, just as we see a tendency for
Speaker 1: external symmetry and biological organisms, we at least to some extent,
Speaker 1: see a tendency toward even numbers. Again, huge caveat here.
Speaker 1: It kind of it can also depend on exactly how
Speaker 1: you want to cut it, because you know, you can
Speaker 1: take a quick survey of your own body, and chances
Speaker 1: are you're going to find some even numbers in play.
Speaker 1: You know, two arms, to let, four limbs total, ten fingers,
Speaker 1: ten toes, two eyes, two nostrils, and so forth. On
Speaker 1: the other hand, I mean, yes, you do have one
Speaker 1: mouth and so forth. But you know, the still of
Speaker 1: course lines up with the basic idea of bilateral symmetry.
Speaker 1: Divide a creature down the middle and you have two
Speaker 1: equal sides, though of course we also have to throw
Speaker 1: in the other caveat that the average human being is
Speaker 1: not perfectly symmetrical, and artificially symmetrical faces tend to read
Speaker 1: as uncanny to us.
Speaker 2: For this reason, we actually did a series on biological
Speaker 2: symmetry and asymmetry a couple of years back. I don't
Speaker 2: recall it was that the series called The Lesser of
Speaker 2: Two crab Claws, where.
Speaker 1: I think the fiddler crabs mm hm, yes, Because you know,
Speaker 1: there are plenty of examples too in the biological world
Speaker 1: which we get into in that series, where there is
Speaker 1: a glaring asymmetry. So anyway, it would be a gross mistake. Though,
Speaker 1: coming back to odds and evens, if you were to
Speaker 1: say that you only see even numbers and organisms. That
Speaker 1: is absolutely not true, and they're ultimately far more common
Speaker 1: place and satisfying ways to apply numbers more universally to nature,
Speaker 1: such as say the Fibonacci sequence so forth. But it's
Speaker 1: still interesting to see cases where there is that there
Speaker 1: seems to be a tendency toward even numbers, and still
Speaker 1: looking at the exceptions to those possible rules and possible tendencies.
Speaker 1: One place that start is with chromosomes. So a chromosome
Speaker 1: is a DNA package that contains all the genetic material
Speaker 1: of an organism, and the chromosome count for individual species
Speaker 1: varies greatly, and it has nothing to do with it
Speaker 1: doesn't correlate with the apparent complexity of an organism. So
Speaker 1: you know, for example, a jack jumper and has a
Speaker 1: single pair of chromosomes, while turkey has eighty. A human
Speaker 1: of course has forty six, and then you have a
Speaker 1: case like and to be clear, you can also get
Speaker 1: odd numbers via genetic disorders. But one of the biggest
Speaker 1: examples it's often brought up of an odd number of
Speaker 1: chromosomes in an organism is the mule. This is a
Speaker 1: cross between donkey and a horse of course, and it,
Speaker 1: you know, tends out for having sixty three and they're
Speaker 1: usually infertile because of this. And there's some other interesting
Speaker 1: outliers as well, like the Indian Mutjak, in which males
Speaker 1: tend to have seven to the female six. In the
Speaker 1: swamp Wallaby you see eleven for males and ten for females,
Speaker 1: and there are various other examples of this nature. But
Speaker 1: of course this is all hidden to the naked eye.
Speaker 1: Limbs stand out far more in human consideration when we're
Speaker 1: talking about evens and odds, and so this raises the
Speaker 1: question what if anything naturally has an odd number of arms?
Speaker 1: And basically the answer is nothing except blank. And I'll
Speaker 1: come back to the blank in just a second. But
Speaker 1: there's one potential possibility that often comes up if you're
Speaker 1: just scanning the names of the popular names of organisms,
Speaker 1: and it's one. There's one that came up on a
Speaker 1: Monster Fact episode several weeks back. There is a species
Speaker 1: of octopus known as the seven armed octopus.
Speaker 2: Now that is an oxymoron, isn't it right?
Speaker 1: Right? Because if you know anything about octopi, it is that,
Speaker 1: as the name implies, they have eight arms. So if
Speaker 1: you had a seven armed octopus that that would be interesting.
Speaker 1: Why does it have why does it seem to have
Speaker 1: seven arms? So this octopus is also known as the
Speaker 1: septipus or the blob octopus, and it is Halofron atlanticus.
Speaker 1: And here's the thing, it actually does have eight arms.
Speaker 1: It like, do not believe the popular name. Uh, it's
Speaker 1: just that the males specialized fertilization arm. It's hectocoidalus remains
Speaker 1: coiled away in a sack beneath the right the right eye.
Speaker 1: So this is a specialized arm. In various sephalopods have
Speaker 1: these and there it's the kind of arm that will
Speaker 1: be used to slip in genetic material or sometimes it
Speaker 1: is like left detached and left with the mate. So
Speaker 1: this species has a specialized arm for mating, and it
Speaker 1: keeps it stored away out of sight behind the right eye.
Speaker 1: And so if you're just checking out the specimen and
Speaker 1: you don't know what to look for, you might see
Speaker 1: only seven arms and assume, well, here we are, it's
Speaker 1: a seven armed octopus. But like I said, there are
Speaker 1: some examples of animals with an odd number of limbs.
Speaker 1: But to find one we have to look to the
Speaker 1: marine invertebrates known as c stars, which tend to boast
Speaker 1: five arms, though they can't have more depending on the species.
Speaker 1: Five arms in a radial presentation. I mean, everyone knows
Speaker 1: what a starfish looks like. You've seen SpongeBob. You get
Speaker 1: the general idea.
Speaker 2: Oh okay, and here's where we get into the different
Speaker 2: types of symmetry that are found in animal body plans. Right.
Speaker 2: Because while most animals, and especially most animals we're familiar with,
Speaker 2: have a bi ladder really symmetrical body plan it can
Speaker 2: be divided down the middle and folded in half, there
Speaker 2: are some animals that live, especially in the ocean, that
Speaker 2: have a radially symmetrical body plan, meaning it can be
Speaker 2: it is symmetrical in that it has copied segments, but
Speaker 2: they are copied by going around in a circle instead
Speaker 2: of folding in half down the middle.
Speaker 1: Yeah. Yeah, And this is a This is especially interesting
Speaker 1: concerning the sea star because this comes back to something
Speaker 1: we talked about perhaps last October as well, that, according
Speaker 1: to some analysis, particularly a twenty twenty three study publishing
Speaker 1: the journal Nature by Formery at All, the c star
Speaker 1: is really more of the head with five or more extensions.
Speaker 1: They're not really arms. They're more like head projections, which
Speaker 1: is an interesting way of looking at it. But another
Speaker 1: thing that they point out in this article is that
Speaker 1: sea stars evolved from an ancestor that add two fold
Speaker 1: or bilateral symmetry, and it develops from larvae that also
Speaker 1: have twofold or bilateral symmetry, but they have a typically
Speaker 1: you know, fivefold radial adult body plan. So yeah, another
Speaker 1: fascinating example. Now, another place to look for even numbers
Speaker 1: in a mammal is, of course, look to the nipples.
Speaker 1: Humans typically have two of these, though to be clear,
Speaker 1: you do have situations where people have, like say, a
Speaker 1: third nipple, but generally speaking you're dealing with a two
Speaker 1: nipple scenario. If you have a cat, you can. I
Speaker 1: don't recommend feeling around because unless you're a professional, because
Speaker 1: you will often get clawed for this. But cats have
Speaker 1: six to eight nipples, and indeed most mammals have an
Speaker 1: even number of nipples. But if you turn to the marsupial,
Speaker 1: the American opossum, you will find a famous outlier here
Speaker 1: with an array of thirteen nipples.
Speaker 2: Now, don't start putting your cultural associations on the opossum.
Speaker 2: No one of its nipples is the unlucky one.
Speaker 1: Now, because when you look at the number of young
Speaker 1: they have like it's it's it's the like the ghost
Speaker 1: nipples past thirteen that were the unlucky ones, because they
Speaker 1: generally have and this is environmentally dependent, they generally have
Speaker 1: like twenty young. So not everybody's gonna get a nipple
Speaker 1: and survive. But but yeah, you can. You can look
Speaker 1: up I don't strongly recommend the opossum nipple google image search,
Speaker 1: but you can. You can find some illustrations that I
Speaker 1: think are ultimately more helpful and better for you, know,
Speaker 1: your sanity, than looking up the actual images of opossom
Speaker 1: nipple arrangements. But the illustrations give you the general idea.
Speaker 1: So I've seen this described as two arches of six nipples,
Speaker 1: with one nipple located centrally. I've also seen it talked
Speaker 1: about in terms of being like a U shape or
Speaker 1: circular shape inside of the female opossum's pouch. Now, there
Speaker 1: are various other classifications of the un and odds we
Speaker 1: might get into there. Of course, odd toed and even
Speaker 1: toed ungulates. Tapers, for example, have four hoofed toes in
Speaker 1: the front and three hoofed toes in the back. Most
Speaker 1: rhino species have three digits on each foot and in general, though,
Speaker 1: and we've gotten into this a bit in the past,
Speaker 1: especially when we talked about horse hoofs, evolution has resulted
Speaker 1: in digit numbers greater and less than the human five
Speaker 1: that we take for granted, you know, because you can
Speaker 1: look at the horse's hoof and see it as a
Speaker 1: single toe, a single great toe foot. And we see
Speaker 1: the opposite as well in some other organisms, with the
Speaker 1: development of a sixth pseudothumb. This is you can find
Speaker 1: these in the giant panda, for example, where this has evolved.
Speaker 1: It's not truly an additional digit on the hand, but
Speaker 1: it is basically like doing the work of an extra
Speaker 1: partially evolved digit to aid in the NonStop consumption of bamboo.
Speaker 1: And then we also see a remarkable pseudo thumb emerge
Speaker 1: on the hand of the II lemur. So the II
Speaker 1: lemur may be a lemur that a number of view
Speaker 1: familiar with from various nature documentaries, because it is a
Speaker 1: very weird, goblin esque looking creature. It's it's it's wonderful,
Speaker 1: I say it is. It is weird. In all of
Speaker 1: the great ways that an animal can be weird. You know,
Speaker 1: it is nocturnal. Uh, it again looks kind of like
Speaker 1: a goblin, and it has these very specialized hands that
Speaker 1: feature a super long middle finger, which it uses. Uh.
Speaker 1: It uses it specialized hands to like cap on wood
Speaker 1: and then uses that that super long middle finger to
Speaker 1: reach in and dig out grubs and wood burrowing insects
Speaker 1: to eat.
Speaker 2: Yeah, so it sort of has nose Feratu hands. But
Speaker 2: I can't emphasize enough that the face in many photos
Speaker 2: is going, oh dude, it's like very big wide eyes
Speaker 2: and the mouth open like it is shouting at you
Speaker 2: in excitement and surprise.
Speaker 1: Yeah. So it's the situation those seems to be pretty
Speaker 1: fascinating here because they have this super specialized again long
Speaker 1: middle finger. It basically has a single use. It's essentially
Speaker 1: a unit tasker. But that means that they need a
Speaker 1: little more help climbing. So it's like, you know, it's
Speaker 1: like they had a callub evolution and say, look, I
Speaker 1: need to put an order in for an extra digit.
Speaker 1: Why you already have five digits. Well, yes, but I've
Speaker 1: specialized one to the degree that it can no longer
Speaker 1: help me in climbing. Trees, So do a search for
Speaker 1: II hands II fingers to get a sense of what
Speaker 1: I'm talking about here. And that's exactly what I was
Speaker 1: doing when I found a mention of a study that
Speaker 1: I had not run across before. I thought I knew,
Speaker 1: like all the main cool things about the ei. But
Speaker 1: as it turns out that elongated middle finger is proportioned
Speaker 1: as such. First of all, that it would be like
Speaker 1: us having a foot long middle finger. But not only
Speaker 1: do they use this to fish out wood boring insects
Speaker 1: and grubs, but according to Anne Claire Fabre and this
Speaker 1: is an evolutionary biologist at the Natural History Museum of
Speaker 1: burn as cited in a Cassidy Ward article for Sci
Speaker 1: Fi in twenty twenty two, they also use this finger
Speaker 1: to pick their own noses, and they get the whole
Speaker 1: finger in there to the point that they're able to
Speaker 1: reach all the way back through their sinuses to the
Speaker 1: back of their throats and then back out again. The
Speaker 1: most prodigious nose picking in nature. It has to be right,
Speaker 1: certainly with fingers with digits. You know, there may be
Speaker 1: other strong candidates. They're involving animals with very like prehinsile
Speaker 1: tongues and so forth.
Speaker 2: But they zoologists right in with better nose picking in
Speaker 2: the animal world.
Speaker 1: I mean, this has got to be one of the
Speaker 1: top cases. So I mean, that's okay. So I'm getting
Speaker 1: off off topic a little bit from the evens and
Speaker 1: the odds here, but that study or and or that
Speaker 1: sci fi article is definitely worth picking up, in part
Speaker 1: because they include an illustration of just how far the
Speaker 1: finger is thought to go into the skull, and you
Speaker 1: get like a cutaway of the II's skull to show you,
Speaker 1: like how deep it goes, all the way to the
Speaker 1: back of the throat. Pretty fascinating.
Speaker 2: You really wouldn't want to, like trip and fall while
Speaker 2: you're doing that.
Speaker 1: No, all right, I have one more biological tie in
Speaker 1: here concerning odds and evens and animals, and this has
Speaker 1: nothing to do with the actual biology of the species.
Speaker 1: It's all about the way we categorize them. We have
Speaker 1: what are called tautonyms. This is when you have a
Speaker 1: speed sees alike Rattus rattus, in which both parts of
Speaker 1: the name are identical. The genus is rattus and the
Speaker 1: species is also rattus, So you have Rattus ratus or
Speaker 1: are rattus.
Speaker 2: Yes, we've discussed a number of these before, But.
Speaker 1: Then there's a step beyond mere tautonyms. There are triple tautonyms.
Speaker 1: This is where the scientific names end up, I think,
Speaker 1: being rather hilarious at times, and resembling as well magical
Speaker 1: spells of summoning, bringing to mind incantations of beetle juice
Speaker 1: and bloody Mary, where you're saying something three times in
Speaker 1: a row, and anything said three times in a row
Speaker 1: will start sounding silly. For instance, there is a buffo
Speaker 1: bufo buffo, the European toad, so it's genus buffo, and
Speaker 1: then the species is Buffo bufo beautiful. We also have
Speaker 1: the black rat that's Rattus ratus ratus, and then we
Speaker 1: have the South African giraffe or giraffa Giraffa.
Speaker 2: Giraffe sounds the most like a spell.
Speaker 1: And there are other fun examples as well, like the
Speaker 1: European eagle owl Boobo Boobo boobo, the Eurasian magpie or
Speaker 1: Pika Pika Pika, and these are all again richly amusing,
Speaker 1: because anything you say three times it's just gonna sound silly.
Speaker 2: Wait, isn't that what Pikachu says?
Speaker 1: Pikachu's definitely, says Pikapka. I don't know if there's a
Speaker 1: third Peka in there or not for.
Speaker 2: When Pikachu really means it.
Speaker 1: Yeah, another interesting thing about this is you'll only find
Speaker 1: these in zoology because they are forbidden in botany under
Speaker 1: the International Code of Botanical Nomenclature. So you're not going
Speaker 1: to find anything like cannabis, cannabis, cannabis because it's just
Speaker 1: forbidden that we don't do that in botany. Leave that
Speaker 1: to the zoologists. They're the silly ones.
Speaker 2: Well, I like this. I think the botanists should do it.
Speaker 2: Maybe they just don't have the guts.
Speaker 1: Yeah, I didn't get in deep enough to find out
Speaker 1: like when this law was laid out and like how
Speaker 1: for what reason? Like why did they really need to
Speaker 1: take a stand on this. But maybe we'll have to
Speaker 1: get into that another time.
Speaker 2: I'm just kidding with you botanists. I know you have
Speaker 2: plenty of courage. All right, Does that do it for
Speaker 2: this series? On even an odd.
Speaker 1: I believe so. Yeah, like you said, we've had our
Speaker 1: third episode. We had a nice odd number of episodes
Speaker 1: for it, so I think we're good to go.
Speaker 2: Obviously, there are even an odd instances of pretty much everything.
Speaker 2: So we could keep going forever, but we got to
Speaker 2: stop somewhere exactly.
Speaker 1: Yeah, yeah, So we'll go ahead and you call it here.
Speaker 1: We want to remind everybody that's Stuff to Blow Your
Speaker 1: Mind is primarily a science and culture podcast, with core episodes,
Speaker 1: publishing and the Stuff to Blow Your Mind podcast feed
Speaker 1: on Tuesdays and Thursdays, short form episodes on Wednesdays. On Fridays,
Speaker 1: we set aside most series concerners to just talk about
Speaker 1: a weird film on Weird House Cinema, and then we
Speaker 1: have some bald episodes or reruns at air on Saturdays
Speaker 1: and Mondays.
Speaker 2: Here's thanks, as always to our excellent audio producer JJ Posway.
Speaker 2: If you would like to get in touch with us
Speaker 2: with feedback on this episode or any other, to suggest
Speaker 2: a topic for the future, or just to say hello,
Speaker 2: you can email us at contact at stuff to Blow
Speaker 2: your Mind dot com. Stuff to Blow Your Mind is
Speaker 2: production of iHeartRadio.
Speaker 1: For more podcasts from My Heart Radio, visit the iHeartRadio app,
Speaker 1: Apple Podcasts, or wherever you're listening to your favorite shows.