Speaker 1: Welcome to Stuff to Blow Your Mind from how Stuff
Speaker 1: Works dot com. Hey, welcome to Stuff to Blow your Mind.
Speaker 1: My name is Robert Lamb and Julie Douglas. We're continuing
Speaker 1: our onslaught against Valentine's Day and all things Valentine's and
Speaker 1: valentine Zan and uh, today we obviously have to take
Speaker 1: on one of the big ones, kissing, Yeah, because I mean,
Speaker 1: what could be more emblematic or even like a physical
Speaker 1: embodiment of love and hearts? Kiss? And we mean to
Speaker 1: dissemble this and show it for what it really is.
Speaker 1: And that's a good question. What is it? Right? We're
Speaker 1: gonna get get to that. Is it something we learn?
Speaker 1: Is it something that we do instinctively? And if we
Speaker 1: do it instinctively, why are we doing it? What possible
Speaker 1: service uh could could could there be in placing your
Speaker 1: lips on another creature's lips and then moving those lips
Speaker 1: around and then what happens back terially? What's the profile
Speaker 1: going on there? Um? And before we dive into some
Speaker 1: of that and even some of the history of the kiss,
Speaker 1: I wanted to mention that Ship Walter, who was writing
Speaker 1: for Scientific American, has a great sort of like lips unfold.
Speaker 1: The kiss from this starry eyed perspective, says quote. When
Speaker 1: passion takes a grip, a kiss locks two humans together
Speaker 1: in an exchange of sense, tastes, textures, secrets, and emotions.
Speaker 1: We kiss furitivelylstiviously, gently, shyly, hungrily, and exuberantly. We kiss
Speaker 1: in broad daylight and in the dead of night. We
Speaker 1: give ceremonial kisses, affectionate kisses, Hollywood air kisses, kisses of death,
Speaker 1: and at least in fairy tales, pecks that revived princesses. Nice,
Speaker 1: I mean, and indeed, there are a lot of different kisses,
Speaker 1: so there's there's no there's no single kiss. There's the
Speaker 1: In fact, if you go by the work of seventeenth
Speaker 1: century German poet, literally historian and translator Martin von kim
Speaker 1: be Uh, he wrote a thousand page encyclopedia of kissing
Speaker 1: that recognized twenty different varieties, including two notable ones that
Speaker 1: kiss bestowed by superiors on inferiors, which we don't really
Speaker 1: get around here at the House of Works, thankfully, and
Speaker 1: uh and also hypocritical kiss. But you mentioned the kiss
Speaker 1: of the kiss of death because of doom. I mean,
Speaker 1: that's a big one too, and instantly brings my mind
Speaker 1: to the Godfather. And of course, uh, you know the
Speaker 1: story of Judas and Christ betraying him with a kiss.
Speaker 1: But the kiss goes back far, far deeper in history
Speaker 1: than that it does. The first documentation of kissing is
Speaker 1: in the four Vedic sanscript texts written in India around
Speaker 1: and it describes the act. And then you have an
Speaker 1: Indian epic poem, Maha Barata, which mentions kissing. And this
Speaker 1: actual this poem was passed down orally for centuries and
Speaker 1: then it was finally written down in threeft C. Yeah,
Speaker 1: we've actually talked about the Mahabarada before. Tells the story
Speaker 1: of the great rivalry between the Curus and the Pandavas
Speaker 1: starting in the middle of the first millennium um b c.
Speaker 1: And you have gods and kings and also the wonderful stuff.
Speaker 1: There's a there's a great uh play and film adaptation
Speaker 1: of the play out there that the English language that
Speaker 1: I definitely recommend people check out. Yeah, it's a very
Speaker 1: rich narrative. Now, another very rich narrative that features kissing
Speaker 1: is the Kama Sutra, which was written in the sixth century.
Speaker 1: Now you throw in a little bit of Alexander the
Speaker 1: Great invading India, and you have, you know, public kissing
Speaker 1: becoming a thing, and it begins to spread, say to
Speaker 1: the Roman Empire, and it sort of comes out of
Speaker 1: the bedroom or the homes of people and out onto
Speaker 1: the streets. Though not entirely so, I mean, this is
Speaker 1: this is very much a Western thing. Yeah. The stats
Speaker 1: tend to say that it's practiced by at least nine
Speaker 1: of cultures among sexual and romantic partners, and that tim
Speaker 1: person is interesting. We started looking back at their the
Speaker 1: accounts of Charles Darwin in his book The Expression of
Speaker 1: the Emotions in Man and Animals. He uh, he talked
Speaker 1: about the rubbing of noses as an alternative to the kiss,
Speaker 1: practiced for instance among the Inuits, where we get the
Speaker 1: idea of the Eskimo kiss the rubbing of the noses. Um.
Speaker 1: And you see also across Africa, the Pacific and in
Speaker 1: the America's um plenty of the examples of people that
Speaker 1: didn't really do the kiss until Europeans introduced it to them. Yeah,
Speaker 1: although especially with with the nezzling of noses, that is
Speaker 1: an intimate act, it's just not as much of a
Speaker 1: bacterial exchange. And I'm even thinking about Hawaiian culture in which, um,
Speaker 1: there's this bowing of the heads next to each other
Speaker 1: and you exchange a breath, so you come very close
Speaker 1: to each other. The idea is that you're you're you're
Speaker 1: meeting each other and taking in a breath. And uh,
Speaker 1: when some of the European explorers showed up, they wouldn't
Speaker 1: do this with the Hawaiian people, and they became known
Speaker 1: as how he's h A O l e. The no breathers,
Speaker 1: that they wouldn't get that close to each other in exchange.
Speaker 1: This moment, I was reading that during the ravages of
Speaker 1: the Black Death fourteenth century Europe, that you saw kissing
Speaker 1: falling out of fashion because obviously there's a lot of
Speaker 1: Black Death going along around, so you kind of cut
Speaker 1: back on some of your your interpersonal physical touching. But uh,
Speaker 1: while kissing fell away, licking, sniffing and nibbling of the
Speaker 1: eyebrows comes into play as an alternative, which, again to
Speaker 1: your point, kind of fills the same void, the close
Speaker 1: intimate physical contact that that makes up for the locking
Speaker 1: of lips. Right, So, even though there may not be
Speaker 1: that specific expression of kissing, there are other expressions like
Speaker 1: the nuzzling of eyebrows. Yeah, yeah, wow, I feel about that.
Speaker 1: It sounds kind of hard to do. I mean, especially
Speaker 1: depending on the how big the nose is. Like, if
Speaker 1: you have like flatter nose, I feel like the otherwise
Speaker 1: you just have to you have to navigate around a
Speaker 1: lot of nose in some cases. All I'm saying, yeah,
Speaker 1: my kid and husband are in for a treat tonight.
Speaker 1: I'm gonna see how the nuzzling of eyebrows goes. Um. Well,
Speaker 1: here's the deal with kissing. Though. It is such an
Speaker 1: important feature of the way that we communicate that there
Speaker 1: is actually a field of study of it called philomatology,
Speaker 1: and those people who are committed to studying kissing have
Speaker 1: brought us a bunch of information about its effects on
Speaker 1: the brain and the body, because if you think about it,
Speaker 1: it is really a full body event when you have
Speaker 1: a good smooch going on. It's true. Yeah, I mean,
Speaker 1: just start breaking it down on a physical level, and
Speaker 1: just not a physical level without getting into you know,
Speaker 1: the nervous system and hormones and what have you. Um,
Speaker 1: I think just in terms, for instance, of the of
Speaker 1: the muscles, right, you have the orbicularious oris, and this
Speaker 1: runs around the outside of your mouth. Yeah, this is
Speaker 1: if you push your lips together, it's kind of hard
Speaker 1: to talk like that, kind of like a pucker those
Speaker 1: that's the bricky lorius. Okay, so that's the big one.
Speaker 1: That's I mean that we're gonna discuss. There are a
Speaker 1: lot of additional muscles, but that's one of the main
Speaker 1: ones that you're flexing when you go in for a smooch,
Speaker 1: because then you have several other muscles around the lips
Speaker 1: that are moving. You have the zygomaticus major the zygomaticus minor,
Speaker 1: you want to use them both of course. Also what
Speaker 1: we're talking about thirty four different muscles here involved in
Speaker 1: the smooch, Yeah, and about a hundred and twelve postural muscles.
Speaker 1: So we think of your neck, back, and your chest
Speaker 1: muscles all being engaged in a full on assault kiss. Yeah.
Speaker 1: Some of the X ray images we're looking at when
Speaker 1: we're putting together this podcast, and indeed the image that
Speaker 1: should be the the cover image for this episode on
Speaker 1: the landing page for this episode of Stuff to Blow
Speaker 1: Your Mind. Uh, you get this sense of this muscular face,
Speaker 1: this communication array that we use to communicate and interact
Speaker 1: with the world. Then it's all. It's all involved in
Speaker 1: this kiss, just on a muscular level, it is, and
Speaker 1: it's exquisitely sensitive stuff going on here, because if you
Speaker 1: think about it, it it all begins with the thinnest layer
Speaker 1: of skin on our body. And of course I'm talking
Speaker 1: about lips, which are among the most densely populated with
Speaker 1: sensory neurons of any body region and as a result,
Speaker 1: or about one hundred to two hundred times more sensitive
Speaker 1: than the fingertips. To think of that, that just that
Speaker 1: initial meeting of the lips is causing a lot of
Speaker 1: data to be uploaded to your brain and carried there,
Speaker 1: which is creating this cascading effect in your body. Yeah,
Speaker 1: a lot of its subconscious as we'll get too into
Speaker 1: as well. They do have nerves. They fire off five
Speaker 1: of our twelve cranial nerves. Uh, So you have all
Speaker 1: this this information firing through the nervous system, sensory information
Speaker 1: going to the brain for processing. Yeah, and that's right.
Speaker 1: So it's shuttling on all sorts of messages um about temperature, tastes,
Speaker 1: smell and movements of this entire smooch going on in
Speaker 1: the summato sensory cortex, which extends from one side of
Speaker 1: the brain to the other, and it has a large
Speaker 1: portion that's devoted to picking up signals from the lips,
Speaker 1: the tongue, nose, and cheek areas, and then it maps
Speaker 1: that and in that map, the lips loom really large.
Speaker 1: It's kind of like a neon sign here when you're kissing,
Speaker 1: because the size of each of those represented body parts
Speaker 1: or regions is proportional to the density of its nerve endings.
Speaker 1: So again, as I mentioned, the flips have a ton
Speaker 1: of nerve endings. When they're engaged on that map, it's
Speaker 1: just saying, hey, this is huge, this is important. Yeah.
Speaker 1: It brings me back to the homunculous images that a
Speaker 1: lot of people probably seen, Like not the actual medieval
Speaker 1: alchemical homuncular little dude, Yeah, not the little dude that
Speaker 1: you're growing in a vat. I love that, but the
Speaker 1: representation of the human body as it would appear if
Speaker 1: size was determined by nerve endings. So it's just like
Speaker 1: a little squat little dude with these enormous lips. Oh
Speaker 1: I like that. Yeah. Um, So all of this is
Speaker 1: going on, and as a result, you have neurotransmitters and
Speaker 1: hormones being released, like dopamine. As we know, it's a
Speaker 1: neurotransmitter associated with feelings of deshire and reward, and it
Speaker 1: spikes in response to novel experiences, which is interesting because
Speaker 1: that sort of explains why a kiss with someone new
Speaker 1: can feel so special. Yeah, there's a little bit of
Speaker 1: the butterflies and the nerves going on, but also this
Speaker 1: is new data that you're taking and that's really making
Speaker 1: the dopamine thing. Your brain is saying, my tongue has
Speaker 1: never been inside this mouth before. There's all sorts of
Speaker 1: new information the process. And kissing also stimulates adrenaline, which
Speaker 1: helps our bodies to anticipate what might occur next. And yeah,
Speaker 1: I mean it's all part of that. That's that stereotypical
Speaker 1: passionate kiss. You know, if you're watching the film and
Speaker 1: you see two people just sort of having this very
Speaker 1: stale moment together locking lips, you're not buying it, you know,
Speaker 1: they're not They're not releasing adrenaline, that's not getting them
Speaker 1: ramped up. Yeah. It reminds me also of Gustav Climpse
Speaker 1: the kiss, which is that all enfolding and encompassing kiss.
Speaker 1: That's you know, in the representation of two people kissing,
Speaker 1: just this ornate display of colors and what looks like
Speaker 1: sensations in that painting. Yeah, I mean they the two
Speaker 1: individuals in a really bassionate kiss should look like they
Speaker 1: are trying to eat each other with their mouths. Yeah.
Speaker 1: It should become like a auaborous thing. Yeah yeah, um, alright,
Speaker 1: so we also have heart rates increasing and oxygen flowing
Speaker 1: more freely through the blood vessels pupils dilating. Its interesting. Yeah,
Speaker 1: this one I read is this supports the Yeah, this
Speaker 1: one I read that might be the reason a lot
Speaker 1: of people close their eyes during a kiss, because otherwise
Speaker 1: you're just staring into like really big, wide, crazy eyes
Speaker 1: the whole time, and that can be awkward. Yeah. All right,
Speaker 1: we're gonna take a quick break. When we get back,
Speaker 1: we're going to talk about the bacterial exchange of a
Speaker 1: good old French kiss. All right, we're back, and this
Speaker 1: is where things are going to get a lot more
Speaker 1: interesting because a lot of what we've covered for sort
Speaker 1: of the basic mechanics of the kiss, and so a
Speaker 1: lot of you are probably thinking, well, of course, a
Speaker 1: lot of muscles are engaged of course, Uh, dopamine, serotonin, adrenaline,
Speaker 1: what have you. Is released that seems to happen in
Speaker 1: any kind of human experience that we've discussed. It's worth discussing,
Speaker 1: right Yeah, Like we we see a piece of chocolate cake,
Speaker 1: same thing happens, right Yeah. But when you start looking
Speaker 1: at the bacterial level here, when you start looking at
Speaker 1: the kiss as a convergence of microbiomes, that's where things
Speaker 1: start really getting trippy and taking us a lot, a
Speaker 1: lot further from the realm of passionate Valentine's Day kisses
Speaker 1: and Hollywood, uh hero saves the Day kisses. Yeah, this
Speaker 1: is where we're going to take that kiss and just
Speaker 1: make it the anti Valentine's kiss right now. And we'll
Speaker 1: do that by discussing it is in it because you've
Speaker 1: got that saliva, and you've got mucus membranes, and that's
Speaker 1: in about nine milli milli leaders of water and about
Speaker 1: point seven milligrams of that protein, point one eight milligrams
Speaker 1: of organic compounds delicious, and point seven one milligrams of
Speaker 1: different fats. And then you have a little bit of
Speaker 1: sodium chloride at point four or five milligrams and maybe
Speaker 1: even up to seven different types of bacteria. And although
Speaker 1: it's it's you know, somewhat rare, it's possible to transmit
Speaker 1: mononucleosis herpie simplex one in gastric ulcers. So those are
Speaker 1: a couple of examples of germs that can be swapped
Speaker 1: and lurking in your kisses mouth. It's basically two train
Speaker 1: cars arriving at the station at the same time, and
Speaker 1: they both unload, and it's just people crossing each other
Speaker 1: to get onto each each train, which is you basically
Speaker 1: just describe the study about the French kiss? Uh would was?
Speaker 1: I love that there's even a study about a French
Speaker 1: kiss and I love that. Um. They were cruited twenty
Speaker 1: one couples in this study and had them snug for
Speaker 1: science essentially. Yeah, and this covered people between the ages
Speaker 1: of seventeen and forty five, so it's not just a
Speaker 1: matter of finding a bunch of young kids and getting
Speaker 1: them to smooch. It's so it's a little more varied
Speaker 1: than that. Um. And before they locked lips, the participants
Speaker 1: were asked to swab out to measure the amount and
Speaker 1: the kinds of bacteria presence. You're getting a good idea
Speaker 1: what the current population is inside of mouth A and
Speaker 1: mouth B and C and D yeah, baseline. Yeah. And
Speaker 1: then at this point they asked one member of each
Speaker 1: kissing couple to eat some probiotic yogurt now. And the
Speaker 1: reason here is because this contains strains of Lactobacillus and
Speaker 1: bifeto bacteria serve as markers to look for in the kissy. Yeah,
Speaker 1: that's right, because they know that. The researchers know that
Speaker 1: normally saliva way contain about point one of Lacto basilius
Speaker 1: and biphobacteria. But after these these couples kissed and they
Speaker 1: exchanged their content, it was found out that the bacteria
Speaker 1: in the non yogurt drinking partner rose to point by
Speaker 1: four and this led the researchers to estimate that each
Speaker 1: intimate liplocked and tonguelocked kiss that can last ten seconds
Speaker 1: or more will transfer about eighty million bacteria into your
Speaker 1: partner's mouth. Okay, so people are probably wondering at this
Speaker 1: point is that a good thing or a bad thing,
Speaker 1: because it might sound if you, especially if you're a
Speaker 1: little more on the germophobic side of things and maybe
Speaker 1: a little adverse to kissing strangers. On the bus already.
Speaker 1: This might sound like just an unnecessary invasion of your
Speaker 1: mouth space. It does. It sounds a little terrible, like
Speaker 1: why would we do this in the first place, But
Speaker 1: the fact of the matter is is that the higher
Speaker 1: the diversity of your microbi I am in your mouth, well,
Speaker 1: the better it is for you. Okay, So the more kisses,
Speaker 1: the better, The more passionate the better. I mean, I
Speaker 1: wouldn't know, if someone has, you know, an outbreak around
Speaker 1: their mouth, I wouldn't go kissing on them, or if
Speaker 1: someone is sneezing or you know, I wouldn't pursue you know,
Speaker 1: certain circumstances kissing. But yeah, in general, mean, what doesn't
Speaker 1: kill us makes us stronger, right, Okay. So if yeah,
Speaker 1: so the opportunity for a kiss comes about and it's
Speaker 1: like you would have taken it anyway, definitely go in
Speaker 1: and happy kiss because there's a potential health benefit there possibly,
Speaker 1: But don't hold us to that. All right, We're gonna
Speaker 1: do another break and when we come back, we're going
Speaker 1: to get into the nitty gritty or we're going to
Speaker 1: get into the reasoning behind the kiss and and again,
Speaker 1: because it's going to get into it even Traz your territory.
Speaker 1: All right, we are back. Why do we kiss? Propert Lamb? Well,
Speaker 1: there are a few possibilities, right Um. One of the
Speaker 1: big ones out there, and we touched on a little
Speaker 1: bit already, is that it's just something we started doing
Speaker 1: and that we learned. And you can point to those
Speaker 1: ten percent of humans that don't kiss and say, well,
Speaker 1: it's it's evidently not really a human thing across the board.
Speaker 1: So is it really in a human behavior or is
Speaker 1: it just something we saw on TV? Now I had
Speaker 1: to think about this one a bit and imagine most
Speaker 1: of you can can relate to this, like think back
Speaker 1: to your your first kiss, or even just the first
Speaker 1: time you wanted to kiss somebody, like why did you
Speaker 1: want to kiss them? Like? What was it? Just because
Speaker 1: you saw it on a million movies and TV shows
Speaker 1: prior to that, and you saw it on every advertisement
Speaker 1: because especially here in the U S, it's it's everywhere
Speaker 1: in Western culture, it's the kisses everywhere? So am I
Speaker 1: just picking up on all those signals and thinking That's
Speaker 1: what I'm supposed to do, that is what is expected
Speaker 1: of me. I feel like at first it's a familiar thing, right,
Speaker 1: Like I look at that with my daughter who's just
Speaker 1: started kissing or friends at age four, no matter what,
Speaker 1: because it was her expression of love. And now she's
Speaker 1: six and she's just had her first kiss from a
Speaker 1: boy or however she's casting it. And she also has
Speaker 1: watched a lot of different things that are depicting kisses
Speaker 1: among opposite gendered people. I mean, I mean, she's not
Speaker 1: watching soap operas or anything, but she's watching Ninjago, and
Speaker 1: you know, two of the characters have a little peck
Speaker 1: on the cheek or something. Um, So, in that respect,
Speaker 1: I see it as cultural. However, it's not that easy
Speaker 1: just to say that's the answer, right, So if we
Speaker 1: get into the idea that it is instinctive, they're they're
Speaker 1: roughly three different hypotheses for why do we kiss to arouse?
Speaker 1: Obviously sort of the ramping up to the actual uh
Speaker 1: genetic genetic act of breeding with another person. Um, it's
Speaker 1: also the possibility that it's all about just cementing the relationship.
Speaker 1: And again it has to do with with with with
Speaker 1: mate bonding or essentially testing out of a potential mate
Speaker 1: kind of a genetic test. And this is where things
Speaker 1: get really fascinating. Yeah, and I did want to mention
Speaker 1: too before we kind of dive into those topics when
Speaker 1: when we talk about it being learned. Um, there is
Speaker 1: a British zoologist and author, Desmond Morris, who in the
Speaker 1: nineteen sixties first proposed that kissing could have evolved from
Speaker 1: the practice in which primate mothers chewed food for their
Speaker 1: young and then fed the mouth to mouth, so preasticating food.
Speaker 1: And I feel like we talked about this, Yeah, we've
Speaker 1: talked about I feel like we've talked about that in
Speaker 1: terms of passing on beneficial bacteria to the young as well. Again,
Speaker 1: mouth to mouth contact comes down to bacteria and the
Speaker 1: microbiome and and very minute data passed between mother and child,
Speaker 1: between two mates, etcetera. So evolutionary biology might say something
Speaker 1: along the lines of, so if chimps do it, so
Speaker 1: two could have our hamt id, and so might we.
Speaker 1: And in fact, they're are a plenty of other cultures
Speaker 1: today that will actually do that to cheat their food
Speaker 1: for their baby and instead of using the grinder or something,
Speaker 1: cheat some food for my son before, I mean, not
Speaker 1: not super recently, but it's been done. I mean because
Speaker 1: he's like sixteen now, right, but you know, you find
Speaker 1: yourself in those situations where it's like, all right, I
Speaker 1: could get out a knife and and cut this in
Speaker 1: half for him, or I can just bite the thing
Speaker 1: in half and give him part of it. Why not? Sure?
Speaker 1: And I mean right, it's a convenient thing. And then
Speaker 1: you put the nursing equation with us, which it really
Speaker 1: gets sort of interesting here because then the child may
Speaker 1: be learning to associate lip pressure with a loving act. Now,
Speaker 1: consider that two thirds of all people turn their head
Speaker 1: to the right when kissing. And this is according to
Speaker 1: psychologists on your constrick of your university in Germany. And
Speaker 1: now stay with me. Why does that matter? Because this
Speaker 1: behavior may mirror the head turning preference observed in babies
Speaker 1: when their breastbed. Huh huh it is. It's a hum moment, right,
Speaker 1: It's something to consider, just the whole right handed thing.
Speaker 1: Like I'm trying to think back on and every kiss
Speaker 1: I've ever had if I turned to the right, and
Speaker 1: I guess that means that the other person turned to
Speaker 1: the right too, right, because yeah, I know, againe it
Speaker 1: agether another test from my husband and my daughter running tonight.
Speaker 1: So anyway, just a couple of things to think about
Speaker 1: But there are other reasons that we do this. Indeed,
Speaker 1: and this is where it comes back to that old song.
Speaker 1: It's in his kiss, right, like if he loves you
Speaker 1: or something, it's in his kiss. That's good. Yeah, that's
Speaker 1: the one. So in a way, I'm not sure about love.
Speaker 1: Love is a whole different kettle of fish. But the
Speaker 1: idea of just pure genetic mate selection, just the straight
Speaker 1: up genetic mission that that that governs our lives. Human
Speaker 1: a needs to find a human being so that they
Speaker 1: can procreate and and do what their their their genes
Speaker 1: are telling them to do. The idea here is that
Speaker 1: a kiss serves as an act of chemical profiling that
Speaker 1: human will. A sticks its tongue into human bees mouth
Speaker 1: and uh and and basically conducts a core sample of
Speaker 1: what that that person consists of, particularly their immune system
Speaker 1: and uh and then crunches that data to see if
Speaker 1: this is the type of person that they want to
Speaker 1: bread with. It's a real possibility, especially when you consider
Speaker 1: that A two thousand and nine study of one thousand
Speaker 1: college students by Gordon Gallup Jr. A professor of psychology
Speaker 1: at the University of Albany, showed that of men and
Speaker 1: sixty percent of women reported that after feeling attracted to
Speaker 1: someone initially, the attraction ended after the first kiss, so
Speaker 1: that just that one kiss put the kai bosh on. Hey,
Speaker 1: I don't think we should really go any further here.
Speaker 1: As reading that, Cheryl Christian Baum, author of the Science
Speaker 1: of Kissing, found that women are attracted to men who
Speaker 1: have a different genetic code from their own immune system,
Speaker 1: which is of course the hallmark of sexual reproduction. You
Speaker 1: want to have two different sets of genes so you
Speaker 1: can produce variety in the offspring, right, better, better, stronger offspring,
Speaker 1: and have a better potential for survival. Um. And this
Speaker 1: this kind of meshes with some of the stats to
Speaker 1: show that that women tend to be more into the
Speaker 1: kiss than the men. Well, it is interesting to see
Speaker 1: that slight uptick that men and sixty six percent. You
Speaker 1: could say, to a certain smaller degree, women are a
Speaker 1: little bit more discriminating when it comes to trying to
Speaker 1: ferret out whether or not that person it's compatible with them. Um.
Speaker 1: Gordon g. Gallup says that kissing is quote a complicated
Speaker 1: exchange of information or factory information, tactile information, and postural
Speaker 1: types of adjustments that may tap into underlying evolved in
Speaker 1: unconscious mechanisms that enable people to make determinations about the
Speaker 1: degree to which they are genetically incompatible. So to your
Speaker 1: point earlier, some of this is just subconscious information being processed. Yeah,
Speaker 1: because when you're engaged in that passionate kiss, uh, you're
Speaker 1: not thinking about all this. You're not thinking, all right,
Speaker 1: is this the one is just said, I wonder what
Speaker 1: their jeans are like, I wonder if if we can
Speaker 1: we can produce a child that's going to survive the
Speaker 1: next big plague or what have you. But under the surface,
Speaker 1: there's a lot, potentially a lot of computation going on. Yeah.
Speaker 1: And when you look at literature on kissing, a lot
Speaker 1: of people will site the old sweaty armpits study of
Speaker 1: women sniffing the the t shirts of men that have,
Speaker 1: you know, their sweat on it. And the conclusion to
Speaker 1: that was that they were attracted to men who had
Speaker 1: different um sent profiles from themselves that indicated that the
Speaker 1: men's immune systems were different from them. So that again,
Speaker 1: the greater the diversity here, the better for any sort
Speaker 1: of coupling and perhaps producing of a child later on. Yeah,
Speaker 1: and I do want to come back as well to
Speaker 1: again that the fact that a passionate kiss especially is
Speaker 1: not just a matter of the lips. It's a it's
Speaker 1: potentially a full body kind of experience. You're you're engaging
Speaker 1: in all of your senses, So it's a it's like
Speaker 1: a full sensory read out of an individual. But but
Speaker 1: at the at the shallow end of the intimacy pool. Yeah,
Speaker 1: there was actually just reminds me of the writer Flannery O'Connor,
Speaker 1: and there was a fellow writer who tried to pursue
Speaker 1: a kiss with her, and he said that it was
Speaker 1: so devoid of passion and really any sort of um
Speaker 1: connection that he called it a memento mori. That's what
Speaker 1: she was communicating to him is, you know, there's absolutely
Speaker 1: nothing that's going to go on here, momenta morian is
Speaker 1: in terms of the the artistic tradition of having these
Speaker 1: images that they reminds you that death is imminent. Death
Speaker 1: is the ultimate um destination in life. Right, It's like
Speaker 1: kissing the grim Reaper a little. Yeah, I think there
Speaker 1: were no sparks there between the two. Now, the big
Speaker 1: question becomes, of course humans do it? Do other species kiss? Well?
Speaker 1: Basically No, I mean because when you when you start
Speaker 1: looking at the human kiss, and in all its varied forms,
Speaker 1: and especially the passionate human kiss, there's nothing really like
Speaker 1: apples to apples like it elsewhere in the animal k Yeah,
Speaker 1: some of its interpretation too, right. So you see great
Speaker 1: apes press their lips together to express excitement, affection, or reconciliation.
Speaker 1: That's a big deal too, right, like saying, Okay, it's
Speaker 1: we're good here, right, we're all cooperating. Maybe this happens
Speaker 1: after um, there's been some sort of fight or agitation.
Speaker 1: And according to Chip Walter, writing for Scientific American, binobo's,
Speaker 1: which are genetically similar to us, although of course um
Speaker 1: we are not their direct descendants, are particularly passionate bunch
Speaker 1: again the interpretation here and in in that article for
Speaker 1: Scientific American, Walter says that Fronds B. M. Duwal, who
Speaker 1: is Emery professor, recounts a zookeeper who accepted what he
Speaker 1: thought would be a friendly kiss from one of the
Speaker 1: banobo's until he felt the apes tongue in his mouth. Now,
Speaker 1: if you look to other animals, you'll find other examples
Speaker 1: of sensory apparati engaging with each other. Snails caressing antenna's
Speaker 1: birds touching beaks. There's a lot of snout licking going on.
Speaker 1: I mean, really, if you base your research just solely
Speaker 1: on YouTube clips, look, then it seems like every animal kisses,
Speaker 1: especially animals that are pets, animals that we've anthropomorphized to
Speaker 1: varying degrees, right, Yeah, and elephants too with their trunks entangled, right,
Speaker 1: And they've been observed doing this before too, and trying
Speaker 1: to calm each other down, and um, what seems like
Speaker 1: calming each other down? I mean if you break down
Speaker 1: a kiss into the into terms of one partner, particularly
Speaker 1: that a female getting some sensory information on a potential mate,
Speaker 1: then you see the various exams. I mean, even a
Speaker 1: giraffe sampling urine is essentially the same sort of communication
Speaker 1: that's going on with a kiss. Yeah. And as Walter
Speaker 1: had indicated in the quote that I read at the beginning,
Speaker 1: a kiss can be so many different things. It can
Speaker 1: be sexually motivated, or it could be a cooperative kiss, right,
Speaker 1: or as you had mentioned too, there's like the kiss
Speaker 1: of death. So the motivations are just as varied as
Speaker 1: anything else in the human experience or in the animal experience. Now,
Speaker 1: there's some additional benefits to kissing. Um. We already touched
Speaker 1: on potential microbiome related benefits, but just on a regular, relieving,
Speaker 1: daily stress level of activity, it seems like a good
Speaker 1: passionate kiss here and there will definitely set you right. Yeah,
Speaker 1: it will reduce your stress hormone cortisol, thereby lowering blood
Speaker 1: pressure and optimizing your immune response. That's the thought at least.
Speaker 1: And it could even help fight cavities, right Like, if
Speaker 1: if you swapped spit with someone else via a kiss,
Speaker 1: then you may adopt a bacterial strain that can really
Speaker 1: fight against plaque that you lack. You you lack this
Speaker 1: bacterial strain. In fact, there's this idea that you could
Speaker 1: even one day have bacterial mouth transplants. I mean, you
Speaker 1: call them kisses, but I mean you could actively seek
Speaker 1: someone who has a great bacterial profile in their mouth
Speaker 1: and say, I would like some of your saliva. Yeah.
Speaker 1: And also it's just worth noting that kissing, the very
Speaker 1: active kissing, also produces more saliva in your mouth, and
Speaker 1: more saliva is good if you want your natural defenses
Speaker 1: against plaque to take action. Indeed, Um, so that's kind
Speaker 1: of you know, an overall. I mean, and it's just
Speaker 1: great too. Write kissing is a pretty awesome thing. I
Speaker 1: like it. Um, it can also apparently ease pain. There's
Speaker 1: there's some evidence for this is a little a little
Speaker 1: if you be aware of anyone who says they'll take
Speaker 1: your pain away with a kiss. But you do have
Speaker 1: blood vessel dilation going on, so arguably there can be
Speaker 1: some minor level of pain relief going on, or at
Speaker 1: least distraction. That's what I was thinking. At the very least,
Speaker 1: it's distracting in a good way if it's welcomed, of course. Um,
Speaker 1: and let's let's talk about welcomed and I'm welcomed kisses too,
Speaker 1: because I've read this a little bit. If you engage
Speaker 1: in kissing with your pets, you might want to think twice.
Speaker 1: Dogs can carry worms, fun guy, And they can carry
Speaker 1: pathogenetic pastorella in their mouths. And cats. Don't even get
Speaker 1: started on cats. It's like a far worse thing. Well,
Speaker 1: if you own either of these animals, and I own
Speaker 1: a cat, like, you see what they do, You see
Speaker 1: where they you see what they're up to. All right,
Speaker 1: So there you have it. Um, Hey, if you want
Speaker 1: more on this topic, other topics we've covered in the past.
Speaker 1: Go to stuff to Blow your Mind dot com. That's
Speaker 1: where you'll find all of our past episodes or videos
Speaker 1: or blog posts. Links out to our social media accounts,
Speaker 1: information on how to contact us, pictures of what we
Speaker 1: look like, pretty much everything. It's the mothership. Oh, and
Speaker 1: also go to how stuff works dot com. Check out
Speaker 1: how Kissing Works by tray C. V. Wilson. Yeah, this
Speaker 1: article goes into the history, goes into the you know,
Speaker 1: the muscles, the nerves, a lot of the information we've
Speaker 1: discussed here, and you can just you can get it
Speaker 1: all illustrated out there for you, uh, in the ten
Speaker 1: pages or so. Yeah. Also real quick, um, if you're
Speaker 1: interested in finding out more about that study, it's a
Speaker 1: two thousand and fourteen study. It's called Shaping the Oral
Speaker 1: Microbiota through Intimate Kissing. That's the French kissing. One eighty
Speaker 1: million bacteria is strong. All right, you have thoughts, well,
Speaker 1: we would like to put our eyes on them. Please
Speaker 1: send them our way, and you can do that by
Speaker 1: sending an email to below the mind at how stuff
Speaker 1: works dot com for more on this and thousands of
Speaker 1: other topics. Does it How stuff Works dot Com, difficult
Speaker 1: to get youth group, difficult to eat Parlia