The Sexual Evolution (Featuring Dr. Nathan Lents)

Daniel and Kelly talk to Dr. Nathan Lents about sex, gender, monogamy, and other topics from his recent book, The Sexual Evolution. See omnystudio.com/listener https://omnystudio.com/listener for privacy information.

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Daniel Whiteson?

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• 0:07Speaker 01

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• 0:35Speaker 02

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• 1:08Speaker 03

  Hey, I'm Niall Rogers. This fall, I'll be driving across the country, meeting some of today's coolest and most fascinating artists. We'll explore the stories before the moments that changed everything. Because every musician remembers the moment where it all began. Experience before the moment. A Lincoln Original Series on the iHeart Radio app, YouTube, or wherever you get your podcasts.

• 1:46Speaker 04

  When the bias about sexual monogamy came down with birds and that bias finally started to crumble was because of DNA testing. It was invented in the late eighties. And that's really recent. I mean, the late eighties, I mean, I was, I was alive and kicking. I was a budding young biologist in late eighties. And they finally started doing genetic testing and they found every species, one after the other after the other, is they would find these clutches of eggs that had mixed paternity. was not as simple as they had thought, and that sort of forced them to explain it. And that's when the term extra pair paternity and extra pair population was invented. Because, again, if you look at the early papers, it's all about deception and hiding it and cheating, cuckold, you know, moralizing words that we put on these behavior when animals are just doing what

• 2:28Speaker 04

  they do. And if we had just opened our eyes a little bit, because it's not like they do it in secret. There's no reason, we just wanted to see it a certain way. And, you know, when you squint hard enough, you can see nature however you want.

• 2:41Daniel Whiteson?

  Penguins know how to party and they're not ashamed of it, it sounds like.

• 2:44Speaker 04

  That's really a human thing, shame.

• 3:00Daniel Whiteson?

  Hi, I'm Daniel. I'm a particle physicist and I want to learn to party like a penguin.

• 3:06Kelly Weinersmith?

  Hello, I'm Kelly Wiener Smith, and by the end of the show, you'll see Daniel in a very different light.

• 3:11Daniel Whiteson?

  Though you probably won't see me wearing a tuxedo.

• 3:14Kelly Weinersmith?

  No, did you wear a tuxedo at your wedding?

• 3:17Daniel Whiteson?

  No, I'm not a tuxedo kind of a person. I'm not a dress up kind of a person. I'm definitely sandals and shorts.

• 3:23Kelly Weinersmith?

  And that's what you wore at your wedding?

• 3:26Daniel Whiteson?

  No, my wedding, I actually did wear a suit. Suit I had personally tailored for me in China. Yeah.

• 3:31Kelly Weinersmith?

  Whoa, why in China?

• 3:33Daniel Whiteson?

  We were visiting some friends in China and they were like, by the way, if you want a suit tailored, it's $20. And so we just like went down to the market and you buy your fabric in one stand and bring it over. And they're like, yeah, we'll make you a suit out of whatever fabric. So I chose some very nice wool fabric for the outside. And then the inside is this crazy red dragon tapestry.

• 3:52Kelly Weinersmith?

  That sounds awesome.

• 3:53Daniel Whiteson?

  Yeah, it was very cool. Only time I've ever had a suit personally tailored.

• 3:57Kelly Weinersmith?

  Very cool. Do you think it'll be the only time for the rest of your life?

• 4:00Daniel Whiteson?

  Yes, I do think so. Exactly. That was 20 years ago and I haven't done another one since. And so, yes, I think I can extrapolate to one per life. How about you? Have you ever had clothes personally tailored to fit?

• 4:12Kelly Weinersmith?

  I'm sure my wedding dress probably got taken in in some spots, but I don't really remember. And I've certainly never had an outfit. Oh, man. My mom used to make me MC Hammer pants.

• 4:23Kelly Weinersmith?

  Yeah. So she was a seamstress. So no, I guess I had my mom make me clothes particularly for me. And they were mainly MC Hammer pants. Because I was a really cool kid.

• 4:33Daniel Whiteson?

  Well, I can't touch that. Wow. Why MC Hammer pants?

• 4:38Kelly Weinersmith?

  My mom was very talented, but this could have been because they were really easy to make. It's like an elastic band at the bottom and an elastic band at the top and then just a bunch of fabric in between. But also, you know, I mean, I was a kid in the 80s, early 90s. It could have also just been that it was cool.

• 4:52Daniel Whiteson?

  Yeah, I was also a kid in the 80s and I never wore MC Hammer pants. I'm not sure what that says about us.

• 4:57Kelly Weinersmith?

  I'm not sure how that places both of us in the hierarchy of coolness, but, but I have a feeling neither one of us were very close to the top.

• 5:06Daniel Whiteson?

  No, I definitely was not close to the top.

• 5:09Kelly Weinersmith?

  Yeah, no, I was pretty close to the bottom, scraping the barrel.

• 5:12Daniel Whiteson?

  But human society is very complex and social hierarchies are complicated and dating structures are complicated. And today I'm excited to talk to our guest about the complexities of human interaction and what we can learn from the animal kingdom.

• 5:27Kelly Weinersmith?

  I had a lot of fun with this conversation. As I mentioned in the show, when I was in undergrad and grad school, I studied behavioral ecology. And in these classes, you learn a lot about the different ways that animals mate. And sometimes it's upsetting, sometimes it's hilarious, but it's always fascinating. So it was really fun to read his book and see like where the field has gone in the last 15 years and to get some amazing examples of diversity in the animal kingdom. And I think we had a really fun conversation.

• 5:52Daniel Whiteson?

  We certainly did. And though the topics we dive into today are scientific and we try to keep it apolitical and family friendly, there are of course, some things that come up that might reflect on both topics. So keep that in mind as you listen.

• 6:06Kelly Weinersmith?

  And as you decide if your kid should listen.

• 6:10Kelly Weinersmith?

  All right, let's do it.

• 6:15Kelly Weinersmith?

  Dr. Nathan Lents is a professor of biology at John Jay College, City University of New York. He's the author of Not So Different: Finding Human Nature in Animals and Human Errors: A Panorama of Our Glitches from Pointless Bones to Broken Genes. On today's episode, we're talking to him about his newest book, The Sexual Evolution: How 500 Million Years of Sex, Gender, and Mating Shape Modern Relationships. Welcome to the show, Nathan.

• 6:41Daniel Whiteson?

  It's great to be here and thanks for the invitation.

• 6:43Kelly Weinersmith?

  Yeah, we're thrilled to have you here.

• 6:45Daniel Whiteson?

  So let me jump in and ask the first question, the big picture question, since I'm not the biologist. And so the naive question is like, why do we think that animals have more than one sex? Like, why does it exist in the world anyway? And while you're answering that question, maybe you could also clarify like what the difference is between sex and gender, since we're speaking sort of scientifically and technically here.

• 7:09Speaker 04

  Right. These exact questions fill a couple hundred thousand words in my book. So let me try to see if I could distill it down a little bit more. But I mean, I think what you're getting at is a frustration that humans have to want to categorize, name, label, everything so that it fits in these nice neat buckets. We created language to do this for us, right? So we have pronouns that have gender and a lot of languages have gender with the way that they speak. So we just assume that everything fits in this bucket, male or female. It's just there's only two buckets and everybody's has to be in one of them. If you just suspend your need for that for just a little bit and remember that animals do what they're gonna do. They're gonna behave or they're gonna behave and they're gonna create new generations. And they do that through sex, through the mingling of two genomes.

• 7:53Speaker 04

  And then everything else could be, you know, structured in lots of different ways to make that happen. So if we talk about sex, first of all, the difference between sex and gender. Sex is really a physical property of bodies, of cells, of tissues, of organs of a body. It's a physical property, whereas gender is a behavior. It's a psychosocial phenomenon. It's how we interact with one another. And it flows from sex, but it's not purely reducible to sex. So if you can think of sex and gender as like kind of two axes on a spectrum, and there would be more than just these two, because I would put sexuality on a third axis as well. But if you can imagine these as this multi-dimensional spectrum and you can have sex and gender, and they flow together a lot, but not always, you know, there's a trend line that you could draw.

• 8:38Speaker 04

  But there's lots of individuals that will play with sex, gender, and even sexuality. And the environment will select what's most successful. Meaning what's most successful will leave the most offspring and reproduce and persist over time. And one thing that biology has taught us is that All throughout anatomy, physiology, histology, genetics, diversity is the key to a successful species, to a successful lineage. The more diverse you are, the more insulated you are against future changes in the environment. And we think about that in terms of like abiotic environmental conditions, you know, temperature, or even biotic ones like food, whatever. But actually, if you think of the environment also as social, right? So how

• 9:20Speaker 04

  you interact with your conspecifics, you know, the other members of your species. And again, some will be more successful than others. So diversity gets generated all of the time. And when environments change, including social environment, that which is successful will leave more offspring and go on. So I'll try to get to a sum up point here because I know I've been talking for a while. But we've appreciated the diversity in genetics and the diversity of anatomy and all these things for a long time. And we're just now starting to appreciate the diversity of sex and gender itself. And I think that we're just really at the beginning of that. So I have a lot of examples in my book of gender exploration and creativity and diversity in nature. But I think that even 10 years

• 10:02Speaker 04

  from now, this book is going to look very outdated, because we're discovering a lot of this stuff all the time.

• 10:07Daniel Whiteson?

  Well, your book focuses on sex in the animal kingdom, but it sounds sort of like your motivating questions are about sex in humans. Why are we studying sex in the animal kingdom if our questions are about sex in humans? Is that just the easiest place to do these things scientifically, the most ethical? Or do we think that the questions transcend humanity?

• 10:26Speaker 04

  Exactly. The last thing you said, because, you know, humans are animals, right? We're animals, we're vertebrates, we're mammals, we're primates, we're apes. And so we bear the legacy of all of those lineages. And in fact, you know, we didn't just fall out of the sky in our present form, right? We are the product of a long evolutionary process. And we can see that in our anatomy, we can see it in our genes, but we can also see it in our behavior and the way that we approach mating. So that's why I want to look at it from this very broad perspective. And in fact, actually, in some of the early chapters of the book, I go even beyond animals, and I talk about fungi and plants and just what is sex about in the first place? Why do you need two individuals? reproduce when obviously the vast majority of life forms on earth clone themselves.

• 11:09Speaker 04

  That's how they reproduce. I'm talking about bacteria and other microbes. So you don't need sex in order to reproduce. Sex was invented by nature as a way to reproduce, not by cloning, to specifically introduce variants, variants, the plural of variants. Because by having lots of different kinds of individuals, it's like in your investment portfolio. You don't put all your money in one stock, right? You invest in either in an entire industry or multiple industries because you don't know what's going to happen next year or the year after that. And so when you apply that same principle to sex and gender, you know, you don't know what's going to be successful. You don't know whether it's competing against your fellow cons specifics or just in general, you're going to be successful long term. You need a diverse gene pool, and I think that's why.

• 11:54Speaker 04

  So, but you're right, the motivating factor here and why I wrote this book and why I want people to read it is because humans are now in a time where a lot of what we thought was settled about sex and gender, it's all coming under question now. People are are living very differently than they have for a long time. And whether it's marriage rates or the style of relationships or sexuality, you know, same-sex sexuality and so on, and even gender expression, all of these things seem to be up for debate in a way that they weren't 50 years ago or even 25 years ago with some of these. So that's the motivating factor. And hopefully you'll still read the book, but I'll give you the punchline. My thought is that all of that we're seeing now is a rediscovery of a more diverse and expansive relationship with sex and gender that our ancestors used to have,

• 12:39Speaker 04

  our human ancestors, but our animal cousins enjoy today, a much more expansive view of sex and gender. That's not so categorical and restrictive.

• 12:48Daniel Whiteson?

  Well, I mostly read the book looking for investment advice, so I'm very glad that there was some of that in there also.

• 12:54Speaker 04

  I just saw that the stock market plunged this morning. And the thing is, that's funny about it is that, again, it's specific industries. There's plenty of stocks that did great today, so that's the point.

• 13:03Kelly Weinersmith?

  So I'm a big fan of freshwater fish and I think the bluegill sunfish system is a really nice example of diversity.

• 13:09Speaker 04

  Right.

• 13:10Kelly Weinersmith?

  And a really nice way to explain the difference between sex and gender. So could you tell us about that system and sort of our history of how we've understood that system?

• 13:17Speaker 04

  I'm glad you chose that one because bluegill sunfish, these are something that most Americans and Canadians are familiar with because they're the most abundant, one of the most abundant fishes in lakes and ponds and streams around North America. But I bet most people don't realize how diversely they approach gender. So for example, females in sunfish do not nest. They do not build a nest, they do not protect the eggs. For them, reproduction really is a squirt and go. They squirt their eggs and then they leave and that's really it. One day of the year is the entire sexual activity. And females school together, interestingly, but they really have nothing to do with childcare or nest building or any of that. So they're sort of the deadbeat moms, so to speak. So they're the least interesting gender when it comes to sunfish. But the males, when they're preparing for spawning day, males will spend a couple of

• 14:02Speaker 04

  weeks building the best nest. And the males compete against one another for the biggest nest, for the most centrally located, because you know, they also school together somewhat. And so you have a region where the nests will be that really outside regions are not very desirable because they're more prone to, you know, predation and things and the inner ones are the most kind of protected and insulated. And so they fight with each other to a certain degree for the best spot and the biggest nest. But that's only most males. It turns out there are some males that are a little different. They don't build a nest and instead what they do, well, there's actually three varieties of males. So the smallest ones, they don't bother with any of this and they literally wait for the females to come squirt their eggs and then they start to dart in and try to steal some

• 14:44Speaker 04

  paternity by just, you know, squirting the sperm towards the recently laid eggs. That's called a sneaker and we've known about those kinds of males for a long time.

• 14:52Daniel Whiteson?

  I love that expression, steal some paternity. Wow.

• 14:55Speaker 04

  Steal some paternity. You know, it's a good strategy because you have, no effort really is involved, you just have to be fast and small and sleek and a little camouflage. So they're the most darkly colored of the males so that they try to blend in with the background. We've known about sneakers for a long time, but what's interesting to me in a variety of species, what's interesting- Interesting to me is we kind of dismiss them as runts. You know, the suboptimal males that really, you know, kind of frustrated by this submissive position. That's all they can do. So another way to look at them is a minority strategy that's fairly successful. It wouldn't be successful if they all did that. But if you can stay sort of just being different, sometimes gives you an advantage. But the most interesting males are the third gender of males. And I do consider these genders because, you know, they're really different ways of expressing their maleness.

• 15:40Speaker 04

  This third kind are called the cooperator males, or sometimes called medium sized males. So what they do, they don't try to build a nest and they don't try to woo females. Because the large males do try to seduce females or court females. But what the medium sized cooperative males try to do is they try to court other males, the big males, into a partnership. So they're trying to convince one of the large males to take them on as a partner, a subordinate partner. And they won't build the nest, but they will stick around and protect it once the eggs are laid. But what they do is on spawning day, they come in and they try to find a mate, a male mate, that together they can woo females.

• 16:19Speaker 04

  And what we found is that, all things being equal, females actually prefer large males that have a cooperator male. Because now their eggs will be protected by two males after they've laid them and they're fertilized and developing. Now, having cooperative male isn't everything, because having a large central nest is still desirable over one of the smaller, more exterior located ones. And those males generally don't take a cooperator because they don't need the help. And so they're going to father all or almost all of the eggs. But more towards the periphery, there's a little bit more competition. And some males have figured out that if they pair up, they can make up for their poor nest location or size by having two protecting the eggs. And some females have recognized that that's also a good strategy.

• 17:02Speaker 04

  So what you see is this diversity of strategies. And why is this good for the species? Well, you know, the environment could change. That pond may look very different a year from now, 10 years from now. And so having a variety of sort of rewards, you know, for different systems built in. And in fact, actually Joan Ruffguard was the one who really made this example famous. And she has a different point of view. Again, she thinks that Part of what attracts the females to the large males, if they're willing to take a cooperator, is that they're more social by nature. They're less antisocial, less territorial, and that too could have advantages for the species long term. So there's just a variety of reasons, and I'm really excited that biologists are going to be able to start testing some of these hypotheses and see if gender diversity really is good just in and of itself.

• 17:44Kelly Weinersmith?

  I've worked out in freshwater lakes a lot, and I've noticed, you know, you scare a male, so I've worked on small mouth bass, you scare a male away, and loads of minnows immediately come and start to try to eat all of the eggs. And I think I hadn't appreciated until I saw it myself, just how much risk there is of eggs getting sort of gobbled up. And so how great it would be to have somebody who's like always there to defend the eggs.

• 18:04Speaker 04

  Yeah.

• 18:05Kelly Weinersmith?

  So I got a PhD in behavioral ecology like 15 years ago. And so, but when I was learning about the bluegill sunfish system, I learned about those cooperator males as female mimics.

• 18:15Speaker 04

  Uh huh.

• 18:16Kelly Weinersmith?

  And so the idea there, as you mentioned in your book, is that they're not actually cooperating and teaming up with the males. They're tricking the males into thinking that they're another female who's gonna lay eggs, but then surprise, they're actually stealing some paternity.

• 18:28Speaker 04

  Mm hmm.

• 18:29Kelly Weinersmith?

  And so how did we go from having one view of how that relationship was working to our current view?

• 18:34Speaker 04

  I hate to say this, but I think a lot of our views of these cooperator males were based on this bias, this sort of heteronormative bias, and this idea that there's only one correct way to be a male, and that's to be strong and dominant and big and all of that. And we're seeing that these are not always the case. So, and actually in sunfish is a good example that they do have some markings, the cooperator males do have some markings that females also have, but it's not like all of their markings are female typical, right? They'll have a mixture. And that's what we see a lot of these sort of additional genders, particularly in males, that have been called female mimics over the years. And in some cases, it might be, maybe they truly do fool the males. I don't want to say that the entire field is wrong about this.

• 19:16Speaker 04

  But what I think is a more likely explanation is that the signals that they've adopted from the female morphology are to disarm the aggressive instincts, right? You gotta remember, the fish brain's very small, right? So it's not quite stimulus response, but you know, it's a little bit better than that and not much. And so if you have a signal that is pacifying. Meaning that prevents the male from chasing you out. It's like a flag of I come in peace. Hey, hey, I'm not trying to steal your paternity. I'm trying to work with you. And the thing is, is that they do engage in courtship. So you'll have male, male courtship and they put their genital openings together and they kind of quiver a little bit. It looks like sex. It looks like what we think of as sex. But the thing is, is that's really where the female mimicry ends because they then partner.

• 20:00Speaker 04

  The females just go in and squirt the courtship. The whole thing lasts less than a minute and they're gone. Right? So these males don't act like females and they approach the nest differently. They approach from above rather than from horizontal line. And the reason why they approach from above is so that the male doesn't get confused. I mean, that's the idea is that if they approach from above and kind of float down gently, the male could see what's going on and say, ah, okay. So this is a cooperator male. Maybe I'll accept him. Maybe I won't. Maybe I'll chase him off. But if he approaches as one of the other males would, he would get frightened off or chased off, whereas the females don't do that either. So it's, it's one of these things where there's not that much female mimicry involved in their morphology or behavior. Instead, what you see is sort of a blend in male, female, and then of course some new behaviors.

• 20:43Speaker 04

  And I, of course, in the book, I go through other examples where I'm not sure female mimicry is the best explanation.

• 20:50Daniel Whiteson?

  So it sounds like what we're doing here is a lot of imposing our concept of sex and gender onto the animal kingdom where things are actually very complex. And we're like drawing dotted lines along something through the spectrum, sort of the way we think about like, is Pluto a planet? Is it not a planet? Who really cares? It's just a dotted line. It's an arbitrary distinction. But you're also using two very different species here. We're talking about tiny fish versus complex humans. How much do we know about how this changes as you go from species to species? Like, do we have examples? In your book, you talk, for example, about the Varunga mountain gorillas. Can you tell us a little bit about the situation there? Is that more like what we see in human society or more like the fish?

• 21:30Speaker 04

  Well, actually, I think it's a good parallel to human in one way is that what we now know about mountain gorillas is that they're flexible in their gendered behaviors. So this is not an example of having multiple genders living in a culture, but having gendered behaviors completely switch around. And let me explain what I mean. So it was previously thought up until about 25 years ago, that there's really only one way that gorillas live. And they live in very small groups with a single dominant male called the silverback, and then a harem of say, four to eight, somewhere in there, females, adult females that are reproductive. It's a polygynous situation. We have several females for one male. And we thought that's how they live. That's the only way they could live. And when they have their children, the children are the genetic offspring of the male.

• 22:14Speaker 04

  And as they grow up, they have to eventually leave. Otherwise, they're going to be challenging their father, the only male there, and they don't want to do that because they're not big enough yet. So they grow up and then once they start to be a threat, they leave and hopefully take over their own harem one day. Obviously, the math is mathing. Most of them don't make it, right? So actually, any males, any human males who are jealous of the harem lifestyle, just remember that most males die as frustrated versions trying to take a harem. And even the ones that do are constantly, you know, looking over their shoulder because someone wants to take over their harem.

• 22:47Daniel Whiteson?

  And sell mountain gorillas, never thought of that.

• 22:49Speaker 04

  I mean, most of them would be, unfortunately. But what happened in Varunga, so this is a preserve in Uganda, some mountain gorillas started living a different way, where the males didn't leave. You know, the juveniles became adolescents, and they just were tolerated and they stuck around. And these groups have now swelled. We call them multi-male, multi-female groups, which we did not expect gorillas to ever do. But in two generations, they've been doing it now for about two full generations, you have these groups that sometimes have 60, 70 members in them, seven or eight adult males. Now, the adult males aren't particular, they're not social partners, they'll kind of avoid each other, but they do seem tolerant of each other's reproductive behaviors, which is again, something no one would have predicted. And they're doing fine. They're doing great.

• 23:33Speaker 04

  And in fact, a lot of people are taking a closer look at the females in these settings because, you know, the idea that the male is in charge is also Wrong. The only thing the male's in charge of is who gets to mate with the females. That's it. The social life of this group is really dominated by the females. You have an alpha female and they're ranked downward from that. And so what goes on in the social life of these groups is really female dominated. It's just the male controls sexual access to the females. That's really it. So what are the females doing differently to allow their children to grow up and then form these large groups? We don't really know. What we know is that it happened quickly and that everybody's fine. They're thriving. And what it teaches us is that gendered behaviors are flexible, that they can completely switch, given a change in social environment,

• 24:18Speaker 04

  and it doesn't cause a big catastrophe. Because we had tried in zoos to put two males together and of course, one kills the other. But because they weren't socialized with this. But when these males now are socialized with it, they're fine. They're tolerant. You know, a new society is sort of emerging right under our eyes. And so I think it's changed how a lot of us see gender in the animal world to see that they all are a product of their history. And that history could change and will change and they'll live differently. These aren't universal laws of nature that gorillas have to exist in a one male group, that it can take different forms. So if they can do it, certainly we can do it.

• 24:55Daniel Whiteson?

  Well, what is the inciting incident there? I understand if you're a male and you grow up in this environment, you can learn from it and propagate it. It could continue, but how do you go from one male to two male?

• 25:05Speaker 04

  Nobody knows.

• 25:06Daniel Whiteson?

  Nobody knows.

• 25:06Speaker 04

  No, no, we're just watching. And of course, some people are wondering it's, well, they're in a protected environment. You know, maybe that's changed it, but I mean, what are they protected from there? That's different than anywhere else is just poaching, which is human interaction. They're a little bit more protected from poaching. But I mean, remember that poaching was something that wouldn't have been a long part, million year part of their history or anything. So could the presence or absence of poaching explain it doesn't really follow? I don't see that, but from anything else that could get them, you know, they're living just as they would anywhere else. So nobody knows. And not enough people know about that. I'm hoping more people will now that it's in the book.

• 25:42Kelly Weinersmith?

  I thought that was awesome. I feel like, you know, you learn about a mating system on Animal Planet and you're like, got it. I know what the gorillas are doing. But, you know, to come back a couple of decades, the gorillas are doing something else.

• 25:51Speaker 04

  Yeah, yeah. And we see this with lions, too. You know, a lot of people think of lions as having a single male dominating a pride, but that's not true either. Actually, I don't know about the exact numbers on it, but a fair number of lion prides are dominated by a coalition of males. I should say led by a coalition of males. Once again, the females are more in charge of the social life of the pride. It's really just the mating privileges that the males seem to dominate. But yeah, coalitions of males run lion prides as well. It's not as simple as just the lone male, you know, beating off all the other males and, you know, it's just, it's more complicated.

• 26:23Kelly Weinersmith?

  All right, we're gonna take a break. And when we come back, we'll talk more to Dr. Nathan Lents about the sexual evolution.

• 26:40Speaker 01

  That sound? That's the National Squash League. Pro teams, the world's best players, and rallies so fast you'll forget to breathe. Season four is in full swing and every match streams free on YouTube. Big hits, bigger rivalries, and a front row seat from wherever you are. Watch every match for free on YouTube. Search National Squash League and hit subscribe or follow live updates on Instagram at NSL.Sport.

• 27:09Speaker 03

  Hey, it's Nile Rodgers, host of Before the Moment, a Lincoln original series. I'm driving across the country, meeting some of today's most fascinating artists. We're exploring the stories before the moment that changed everything. This week, I'm joined by breakout singer-songwriter Alex Warren.

• 27:29Speaker 06

  To this day, Ordinary would not have done anything, and I would have not been able to put it out if Book Talk didn't back it up and if my wife and a friend didn't back it up. So, pretty crazy how like- Just one thing.

• 27:40Speaker 03

  Right.

• 27:41Speaker 06

  I mean, you, I bet you, we could point to nine different things in our careers where it's just one thing, all of a sudden, if that one thing didn't happen, then I wouldn't be here.

• 27:47Speaker 03

  What you're talking about right now

• 27:50Speaker 06

  Yeah.

• 27:50Speaker 03

  is what I've been talking about since the beginning of my career. There's these things outside of you.

• 27:55Speaker 06

  Yeah.

• 27:55Speaker 03

  That make everything happen. These other forces somehow came into contact with each other.

• 28:03Speaker 06

  Yeah.

• 28:03Speaker 03

  Help propel you to this place.

• 28:05Speaker 06

  It's just insane.

• 28:06Speaker 03

  Experience before the moment. The Lincoln Original Series on the iHeart Radio app, YouTube, or wherever you get your podcasts.

• 28:15Speaker 07

  Cash flow crunch? OnDeck's small business line of credit gives your business immediate access to funds, up to $200,000, right when you need it. Cover seasonal dips, manage payroll, restock inventory, or tackle unexpected expenses without missing a beat. With flexible draws, transparent pricing, and control over repayment, get funded quickly and confidently. Apply today at ondeck.com. Funds could be available as soon as tomorrow. Depending on certain loan attributes, your business loan may be issued by OnDeck or Celtic Bank. OnDeck does not lend in North Dakota. All loans and amounts subject to lender approval.

• 28:54Kelly Weinersmith?

  All right, so we're back. And next I want to talk about a story that you tell in the book where you had a colleague who asks a question that I've also heard a lot. And the question is, should we expect that there won't be gay people anymore? Because now that society is more comfortable with homosexuality, nobody's going to get pushed into pretending they want to be in heterosexual relationships that produce kids. And so should we expect there to not be gay people anymore because of this? And I feel like I've also heard this question a lot. And I'd love for you to address, for starters, that, you know, this comes down, I think, to the question of like, is there a gay gene?

• 29:30Speaker 04

  Right.

• 29:31Kelly Weinersmith?

  Is there genetics underlying this trait?

• 29:32Speaker 04

  Being gay is definitely genetic, but it's genetic in the way that having a kidney is genetic. Not genetic, as in having blue eyes, is genetic. Meaning, there's not going to be a single gene for your sexual orientation, not even close to a single gene. It's very diffusely genetic. It's going to be controlled by genetic elements all throughout the genome. You can't just isolate this variable and breed it out of the population, no matter how hard you try. That's the punchline of it, but there's more detail into that. And that's why I have almost a whole chapter on the gay gene, as it's called. And the most definitive study that came out from 23andMe confirms that there are some clear elements that seem to associate with it, but they're diffuse and they're spread all throughout the genome.

• 30:14Speaker 04

  And they were only able to capture what they estimated about 25% of the heritability. So even all of these things that are spread throughout the genome, still at most, it's a predisposition. Right? So what we know is that attraction and orientation, again, is not so categorical. It's not like with your genes, you were born to be exactly what you are right now. You know, attracted and everything else. I hate to tell you this, but if you, as you are genetically constituted, were born somewhere else at a different time, you would be a very different person, including in your sexual behaviors. You're not you. You are everything that's happened to you since the moment of conception. But the misconception is that, well, if gay people aren't breeding as much, then there won't be gay people eventually.

• 30:56Speaker 04

  But like I said, it's diffusely genetic. You can't isolate it anyway. But also that really misunderstands something because gay people have only been forced to live in the closet and pretend to be straight for a very short part of our history. You know, if you consider our species is about 200,000 years old, something like that. It's really, even in the ancient times, they didn't have to do that, meaning recorded history, certainly not in prehistory. So you're talking about a very small amount of the history of our species. Was that ever even an issue? So we applied a little bit of negative selective pressure, but which resulted in them breeding more than they would have. So did we promote? It really doesn't follow on any selective model that you can think of. But even more than that.

• 31:40Speaker 04

  Birth rates among straight people are falling and gay people still are reproducing from various ways. So it's really hard to get to any way that it could be true that you would expect this because, you know, the desire to reproduce isn't a heterosexual desire. Same-sex marriages and same-sex relationships aren't as productive of children currently as heterosexual ones, but they're approaching parity because of the differences there. So even what negative pressure there was is slipping away. And I think that more and more, you know, people are going to make that decision regardless. And, you know, straight people aren't being forced to have children either, but by social pressures. I mean, when I say forced, I mean, you know, coerced by social pressure. It used to be like, by the time you're 18 or 19, they're like, okay, be married and have kids, you

• 32:22Speaker 04

  know. But, you know, my generation are raising the kids to say, hey, wait as long as you can, you know, go establish yourself first. And then if maybe if you want to have kids deep into your 30s, you know. So, I mean, everything's changing on this. And the effect of sexual orientation on reproduction is just, it's not a very close relationship.

• 32:40Kelly Weinersmith?

  This is a really interesting argument that I hadn't totally absorbed until reading the book. So like, your genetics maybe have 25% input on your sexual orientation as an adult, and you're saying that in the past, there were no, nothing keeping people from being gay if they wanted to be gay. And we still have gay people. And so those two things suggest that that's a silly question.

• 33:01Speaker 04

  Yeah, yeah, that there's just no connection in general. Yeah.

• 33:04Daniel Whiteson?

  Yeah, I'd love to dig in a little bit more into the state of our knowledge of the connection between the genetics and the sexuality. Does that mean that we can't explain it? Like, it could be encoded in the genes, but the mechanism for determining sexuality is just too chaotic, too complex for us to model? Or does that mean it can't be encoded in the genes and it requires some sort of environmental factor? Like, you know, type 1 diabetes has a genetic factor as well as some unknown environmental trigger? Which is it more like?

• 33:33Speaker 04

  It's both of those things. So I would say there's genetic component to it. But at best, it's a weak predisposition, kind of like your type one diabetes example. But unlike that, the predilection towards type one diabetes is probably going to be a little bit simpler genetically to model and to figure out mechanistically, whereas attraction, we have almost no idea why we're attracted. Even just the regular heterosexual, why are heterosexuality, those attractions, we have no idea about the genetics of it. Really none. And we've got to remember that heterosexuality is rarely scrutinized. Anyway, right? Because it's the default. Nobody really asks, how do you become straight? We have asked it the other way around of how you become gay. And what we've been found is frustrating after frustrating after frustrating study

• 34:18Speaker 04

  is that it's very weakly genetic and there is some kind of environmental influence, either in utero or very early childhood. Nobody really knows. But what it seems to be is this complex interplay between genetics and environment. And one thing we do know is the culture that you're raised in has an influence on how you're attracted. And we know that because of changing beauty standards across time and place, you know, what's attractive. You know, at this time in place is very different than, you know, different times and places. So we know that you absorb something about your environment and that influences it. So no matter what, it's not going to be purely genetic. But where the genes interact and what part of your brain and how that becomes a sex drive, we don't have any idea about it.

• 34:59Daniel Whiteson?

  Does it make sense that it's really complicated, that it's not simple? I mean, it's such an important part of how we become who we are and how evolution works. Why isn't it as simple as genes coding for blue eyes or for brown hair?

• 35:13Speaker 04

  I'm glad you used those examples. The reason why those are simple is because they're recent. Those are a recent genetic mutation that led to that. So it's a nice, simple spot. But I use the example of having a kidney. It's absolutely genetically controlled. Absolutely, but we have no idea exactly what all the complex interplay is because it is essential. Our ancestors have had kidneys for probably at least 500 million years, to use a number from the book. And it's the same way with our sexuality, right? Animals have had something like a sex drive since there were animals, you know? And so, of course, it's going to be embedded all throughout the genome. The older a feature is, the more complicated it will be genetically.

• 35:53Daniel Whiteson?

  Like, if you wanted to engineer a kidneyless human, it would require lots of changes to the genetic code, not just one switch.

• 35:59Speaker 04

  And all of those switches affect other things as well. Yeah, that's why it's just so embedded. You can't isolate that variable. But you can, for example, maybe tweak the genetics such that the kidney might develop a little differently. And if you get really lucky, you could do it so that it doesn't affect any of the other ones. But I mean, where are we with that kind of work? Something as concrete as a kidney, we still don't have a clue about. Something, a psychosocial phenomenon like sexuality, we don't stand a chance. So I'm not really worried about anybody going after the genetics of this because it is embedded all throughout our constitution.

• 36:33Daniel Whiteson?

  And what do we know about the history of sexuality? Like, how far back does it go? I mean, we think probably what the first life form was asexual. Somewhere between there and here, we got sexuality? Was it billions of years ago, millions of years ago? Do we know?

• 36:49Speaker 04

  We know a little bit because what you can do through phylogenetics is you see all of the creatures that have a certain trait, and then you go back to when they converged, and you can say that's a kind of a minimum age for that trait. So with sexuality, that's why I chose 500 million years. Animal sexuality goes back at least 500 million years, to the earliest animals. Because what you see in the origin of animals, and by the way, you also see this in plants separately. Plants and animals both have large gamete, small gamete, you know, sperm, egg. But they clearly have different origins. So it's kind of funny that the two most dominant multicellular life forms both settled on this two-sex system of sperm and egg. Because it's the simplest way where you can merge two genomes together, is have one really

• 37:33Speaker 04

  big cell and one really small cell, and they merge to form a new individual. So once that happened, and preceding that was something we would call mating types, where you have the same sized cell. So they're not really egg and sperm. They're both similar, but they have different mating types. So A and alpha, for example, is the one that's most common in fungi. And they do fuse, so to speak, to form this other thing. But there's no inherent difference between them. Some molecules are different on the surface, but that's it. So that they recognize each other. That's a mating type.

• 38:02Daniel Whiteson?

  Are you telling me that mushroom have no genders? And if so, why do we call them fungi and fungi?

• 38:08Speaker 04

  Well, I don't know that we do call them fungi, except for as an adjective, I guess. No, they don't have sexes, but they do have mating types. Again, I use that as an example of that's another way we could have done things. But both plants and animals went the other way, which is to have gametes, one small and one large. But that's a sex. That's not gender. But it got us on the path towards that. So once you have some creatures making a small gamete, and some creatures making a large one, then you start to have some differences that can then get exaggerated, or built upon, or whatever you want to say. But once again, even that, preceding that were the hermaphrodites. So this first emerged in animals that could make both sperm and eggs. And of course, lots of invertebrate species have hermaphrodites.

• 38:53Speaker 04

  Either they only have a hermaphrodite, or they have hermaphrodites along with males or whatever. So if you look at roundworms, for example, they have males, and then they have hermaphrodites. There are no female only sex in this, which is interesting, actually, in and of itself, because it talks about the different selective pressures that males and females can experience.

• 39:10Daniel Whiteson?

  But this story you're telling us, it's very compelling, but it comes from studying current extant species and their relationships, and then imagining back this sort of tree of life and evolution, right? It's not like we're looking at fossils of hermaphrodites, and we're seeing these things. This is not fossil based information, is it?

• 39:25Speaker 04

  Most of what I just said is not right, because this would have been in very soft bodied creatures that were lucky to get even a single impression, you know, of them. And remember that external genitalia, which is what we kind of use to sex the animal body, that didn't emerge for a very long time, right? Birds, most reptiles don't have external genitalia. So there's not much that can fossilize. It's really mammals that get more exaggerated with that. And mammals are, of course, one of the younger groups of vertebrates. But yeah, we don't have a time machine. Unfortunately, we don't have a time machine. So we have to do the best we can through deduction. Some of that's with fossils, but also, you know, seeing what animals have certain things and then you can deduce back when it first evolved. And some of it's just based on likelihood and where we all could be wrong. Evolutionary biology is like history.

• 40:09Speaker 04

  You find the sources you can and you do the best you can.

• 40:12Daniel Whiteson?

  All right, you mentioned it though. So I have to ask you, if you did have a time machine and you could go back and see like one moment in evolutionary history, what would be your pick? Where are you setting that dial?

• 40:20Speaker 04

  Well, because first and foremost, I'm interested in humans. I would really like to observe foraging humans well before farming. Those are the humans that I think most accurately reflect our state of nature, so to speak, before the culture so outpaced the biology in terms of influence on us. So I would like to see pre agrarian human cultures all around the world. And I bet you, I bet you, they all are different when it comes to all this. And that would, I think, prove my point, that there is no one state of human sexuality, that it's going to take all kinds of different shapes everywhere it goes.

• 40:55Kelly Weinersmith?

  All right, well, let's take a break. And when we come back, we're going to talk about monogamy.

• 41:10Speaker 01

  That sound? That's pro squash. Some of the fastest rallies in sport played inches from the crowd. The National Squash League is back in full swing for season four. The sport is heading to the 2028 Olympics for the first time, and you can see it up close right now in a city near you. Watch every match for free on YouTube. Search National Squash League and hit subscribe or follow live updates on Instagram at NSL.Sport.

• 41:38Speaker 03

  Hey, it's Niall Rogers, host of Before the Moment, a Lincoln original series. I'm driving across the country, meeting some of today's most fascinating artists. We're exploring the stories before the moment that changed everything.

• 41:54Speaker 03

  This week, I'm joined by my friend, John Ledge. What still makes you just sit down at the piano?

• 42:01Speaker 08

  If you sat down at 9 a.m. and then at noon, you had a full song that you recorded and put in your voice recorder or you recorded at your studio, you've just created something brand new that didn't exist when you woke up. What a beautiful feeling it is. I'm always excited to write something new. I've been writing for Broadway, which has been a new challenge with new collaborators and some amazing performers who are triple threats, who can sing and dance and act and do all these amazing things. And I want to keep feeling that. And so that means not resting on my laurels, going out there and continuing to create something new.

• 42:36Speaker 03

  Experience Before the Moment, a Lincoln original series on the iHeart Radio app, YouTube, or wherever you get your podcasts.

• 42:45Speaker 09

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• 43:24Kelly Weinersmith?

  All right, so welcome back to the show. So let's talk about how common monogamy is in mammals. Are we unique in our monogamy? Or is that seen in all mammals?

• 43:34Speaker 04

  What do you mean by monogamy? The opening of the book is we have social monogamy, which is the tendency to form dyads, to form pairs, breeding pairs. And then there's sexual monogamy, which is what everybody's the most hyper about when it comes to humans, which really is sexual exclusivity is how I would define that. Well, sexual exclusivity is extremely rare among mammals. I think eight species of mammals have been found to have any degree of sexual exclusivity.

• 43:58Daniel Whiteson?

  Eight species, not 8%?

• 44:00Speaker 04

  No, eight out of like 6,000. I think it's like 0.15% of mammal species are sexually monogamous. Now, a larger portion are socially monogamous, something like 15% of primates are socially monogamous, which is the tendency to form stable breeding pairs, or stable pairs, we should say, mainly for the purpose of raising children. So, social monogamy is not as uncommon, but in mammals, it's still a minority mating type. And birds are really the masters of social monogamy because of the way that they have external eggs that still require warmth. Really pairing up works best for birds. So, something like 90% of migratory birds have that tendency to form dyads.

• 44:44Daniel Whiteson?

  Wait, but so species that are socially monogamous, they form these breeding pairs, but are not sexually exclusive? What's going on there?

• 44:51Speaker 04

  That's right.

• 44:52Daniel Whiteson?

  They have these pairs, but they sometimes also go out and have fun?

• 44:55Speaker 04

  Yes, exactly. Biologists, for, I mean, 100-plus years, just assumed when they saw two birds, you know, build a nest together, lay the eggs, take turns sitting on them, they assumed that they were sexually exclusive because that was our bias. You know, we saw the model. Those Victorian naturalists saw the perfect model of human marriage, you know, because some of the birds do mate for life. About half of those that do, you know, have very long-term bonds. But unfortunately for us, they're not sexually exclusive in almost any cases. The males will go out and try to find, you know, extra pair populations, extra pair paternity, and the females will accept, you know, an extra pair male for copulation as well. And both parties have an interest in that because it diversifies the genetics of their

• 45:40Speaker 04

  clutch. And remember, diversity is the key. And people are like, "Well, but wouldn't a bird just want to find the best mate and really throw everything in with that best mate?" There is no one best way to be, right? And that's the lesson here is that, okay, this male is great in this particular environment, but you don't know what the future holds. You have no idea what kind of new survival challenges around the corner. So if you're a female, having a variety of fathers in your brood is a good long-term strategy for the success of your brood. Of course, you want to select for healthy, strong, you know, good genes overall. But if some males do things a little bit differently, that's a good hedge investment. Go back to the investment portfolio here. So that's, you know, why females would do it.

• 46:25Speaker 04

  And males, of course, have almost no reproductive investment when they have extra pair copulation. So there's really no loss there. And what I think is interesting about this is to watch how they try to prevent their partner from doing this, because in some species, they really do. So this lack of sexual exclusivity doesn't mean that jealousy isn't an issue or there's going to be drama, because, for example, in some birds, when a male does extra pair copulations, he will then return and feed those females to a certain amount, not as much as his primary partner, but he will, you know, potentially invest a little bit in those. And of course, so his main female has an interest in stopping that. I don't think she cares so much about the sperm, but she cares about the investment

• 47:09Speaker 04

  that she's not getting because he's sharing it. And then, of course, the exact opposite would be true as well. This male doesn't want to be investing a lot in what are not his genetic offspring. So he tries to prevent the female from accepting extra pair copulations, and we're right back to the battle of the sexes. It doesn't really solve anything. And so, you know, people have said like, oh, you think then non-monogamy is, you know, a more natural state and that's what we should all go for? I'm saying, I'm not saying that at all. I'm just saying that there's nothing unnatural about it, but it doesn't mean it's better.

• 47:37Daniel Whiteson?

  Well, how common is monogamy in humans? I mean, I remember reading studies of paternity that suggest that a lot of folks have different parents than they might imagine. You know, we're imposing this vision of monogamy on the animal kingdom, but does it even exist in humans? Do we have any data on that?

• 47:55Speaker 04

  Yeah, we have a lot of data on that. So what you're referring to is misattributed paternity. That's when somebody, the father on the birth certificate is not the genetic father of someone. And when blood typing was first invented around the 1930s, there was a guy in England, I forget his name, but he was a physician, and they wanted to do population studies on blood types, you know, how many are in the different groups and all that. So he went out to the hospitals and they wanted to get births because that was a good chance because you had the families all together. So you'd have mother, father, kid, and if there were siblings, they'd be around. So you could do a whole bunch of testing at once. And he got his results back and he didn't publish them for a couple of years because it was impossible to hide the fact that about 5% of the children that

• 48:37Speaker 04

  were born could not be the result of the father on the birth certificate, meaning the blood type was incompatible genetically. And remember, some misattributed paternity would still result in a compatible blood type. So the 5% was kind of a minimum. If we assume randomness, it would be about 10% was more likely. Now, this could have been an extreme case, particularly in the time period in the 1930s, because at that time, you know, the depression and things like that, it might have been a little bit of a blip. But what we now know is that misattributed paternity prior to like industrialization is somewhere between 5 and 10%. And then after things like blood testing and now DNA testing, it's gone way, way, way, way down. Basically, now we know that you can be found

• 49:20Speaker 04

  out. So, so both males and females, you know, change the way that they approach this issue, but only because they're afraid they're going to get caught. But, okay, but that's from modern society. What do we know about foraging societies? This is what I like to have. Foraging societies, monogamy, the tendency to pair up is common, but it is not universal. There are all kinds of different family structures that you find among hunter-gatherer peoples today, contemporary hunter-gatherer peoples. And sexual, you know, lifelong committed sexual monogamy is not the most common one by far. Polygyny is actually a little bit more common than that. Some versions of promiscuity, you see plenty of that as well. You even find marriages that are purely for, you know, maintenance of family lines and privileges and status.

• 50:04Speaker 04

  That really seems to follow much more than the actual sexual activity, which, by the way, is exactly the same in the history of human marriage. So if you look at the Roman custom is really where marriage started as we know it today as an institution. It was purely about property and investment, inheritance and maintaining of that. And it never included sexual exclusivity as part of it. So the concept of legitimacy, meaning legitimate children, was really invented by the ancients, Greeks and Romans. And it wasn't really about love. It wasn't about sex. It wasn't about anything other than maintaining family status, privilege, wealth. And so marriage as an institution doesn't have quite the romantic past and history that you might expect.

• 50:47Kelly Weinersmith?

  Can I take a couple of steps back in our conversation? So you mentioned that Victorians were a bit scandalized when we started discovering that birds weren't monogamous in the way that we thought that they were. Daniel and I often like to talk on the show about things that sort of blind us to what's actually happening. You know, maybe you don't have the right tools to study a question, but this seems like an interesting example where like human society and our culture is keeping us from understanding what's actually happening. But I loved the story about the Victorian scientist who tried to like hide his results.

• 51:14Speaker 04

  Yes.

• 51:15Kelly Weinersmith?

  Can you tell that story just for fun?

• 51:17Speaker 04

  Right, so he was studying Adelie penguins, which are in Antarctica. So these penguins, they're very sexual. They do all kinds of crazy sexual activity, not just same-sex sexual activity, but sex with juveniles, with even necrophilia. There's kind of every kind of sexual kink you can imagine was represented by these penguins. And he was so scandalized that he took his field notes in Greek rather than in English. He wrote them in ancient Greek because if somebody came across those notes and that wasn't a gentleman, you know, an educated gentleman, they would be scandalized and they would have their virtue stolen from them. And in fact, he had a hard time publishing these results for years. And it was by his own reservations as well. He didn't want it to get out there to the public, the idea that, you know, they could be scandalized even reading it.

• 52:01Speaker 04

  And I think that that shows you the power of bias. I mean, he self-censored in recognition of that bias. But you know, when the bias about sexual monogamy came down with birds and that bias finally started to crumble was because of DNA. Testing. It was invented in the late eighties and that's really recent. I mean, the late eighties, I mean, I was, I was alive and kicking. I was a budding young biologist in late eighties and they finally started doing genetic testing and they found every species, one after the other, after the other, is they would find these clutches of eggs that had mixed paternity. It was not as simple as they had thought and that sort of forced them to explain it. And that's when the term extra pair paternity and extra pair copulation was invented because, again, if you look at the early papers, it's all about deception and hiding it and cheating,

• 52:46Speaker 04

  cuckold, you know, moralizing words that we put on these behavior when animals are just doing what they do. And if we had just opened our eyes a little bit, because it's not like they do it in secret. There's no reason. We just wanted to see it a certain way. And, you know, when you squint hard enough, you can see nature however you want.

• 53:03Daniel Whiteson?

  Penguins know how to party and they're not ashamed of it, it sounds like.

• 53:06Speaker 04

  That's really a human thing, shame.

• 53:09Kelly Weinersmith?

  So what are the big open questions in this field today?

• 53:13Speaker 04

  Well, I think that unfortunately, with my book and a couple others that are coming out this year, I think you're going to expect a lot of pushback and you're going to see a lot of biologists that are really not happy about the notion of gender diversity as something that is a biological phenomenon. They really think that is just kind of humans are being weird and we're overpopulated, so we're doing these crazy gender things. So I think the big frontier is going to be biologists going out and devising ways to answer this question. The hypothesis about whether gender diversity is a better framework for understanding behaviors. Because, you know, we use the framework of female mimicry, for example, and cuckoldry and, you know, this deception based way of assuming animals behave. So the other way is

• 53:57Speaker 04

  the gender diversity framework. So that's just a framework though, right? It's not data, it's not evidence, it's just a framework. So I think what's going to happen, hopefully, is that scientists will devise ways to test. You know, a good framework springs forth hypotheses and hypotheses can then be tested in the field. So we're going to have to see creative hypotheses and creative ways of explaining this. But I also think what's going to happen is the idea of multiple genders within Males or within females, multiple ways of approaching reproductive behaviors. I think that is going to be the hot area right now where we've collapsed a lot of diversity by just thinking about male typical ways of behavior, female typical ways of behaving.

• 54:40Speaker 04

  And then, but once we sort of forget that and stop trying to kind of wedge everything in to meet our expectations, I think you're going to see reports of a lot more reproductive diversity. To me, that's the hot area.

• 54:51Daniel Whiteson?

  So to end the conversation, I'm going to zoom us out and like way, way out and think about not just life on earth, but life in the universe. You know, we learn so much about life by studying here on earth, but it is ultimately N equals one. If you are an astrobiologist and you're landing on some alien planet, do you expect to find life there to be asexual, to be sexual, to have two genders, to have 97 genders? What is your expectation there?

• 55:16Speaker 04

  Well, you're right, we have an N of one. So it's really hard to imagine all the different constraints that you would have on a different planet. But I will say this, the tendency for life to create diverse forms, that has to be universal. I think that is so built into how even molecules behave. If you can use the word behave with molecules, I think you're going to see diverse forms. Whether or not they settle on two sexes will be really interesting. But I think there's some reason to believe that you would see that just because of the advantages of a small gamete and a large gamete, that that solves a lot of technical problems of two cells fusing. So if we assume that diversity will win over asexual reproduction, asexual reproduction does not produce diversity.

• 56:02Speaker 04

  So if we assume that that's a general principle, that diversity generating things will outcompete non-diversity generating things, then I think the mingling of two genomes really will probably fall into a two-sex paradigm. I don't know, but I would say that there's enough reason to think that. However, what their genome is, of course, would dictate all of this too. Because we're assuming, you know, that if they do have a genome, it's going to be DNA and blah, blah, blah, but that may not be the case. So I'm not a astrobiologist myself, but what I understand of that is that some of these principles of natural selection, diversity, reproduction, I think we can expect them to be universal. But one thing I will say is that microbes, even though in my book, I dismiss them as

• 56:46Speaker 04

  less successful, but you have to remember, they're incredibly successful at what they do, at streamlining and simplicity, because there's more E. coli cells in your body than there are human cells in your body. Right? So they've definitely figured out a way to be successful, but that way is extreme streamlining, you know, simplicity. They ditch everything that's not essential to, in order to really just hone in on one thing. But that's why they haven't come to dominate the planet the way that plants and animals have. So I think if we go to another planet, the dominant thing, the thing that we're really concentrating on, plants, animals, fungi, their equivalent of that, I do expect them to be sexually reproducing.

• 57:20Kelly Weinersmith?

  All right. Well, thank you for being on the show and everyone can pick up the sexual evolution at all fine bookstores. Yeah, thank you so much for being on the show.

• 57:29Speaker 04

  It was a pleasure. It was a great conversation. Thank you so much.

• 57:32Daniel Whiteson?

  And thank you for speculating about whether aliens party like penguins.

• 57:34Speaker 04

  I bet they do.

• 57:45Kelly Weinersmith?

  Daniel and Kelly's Extraordinary Universe is produced by iHeartRadio. We would love to hear from you.

• 57:50Daniel Whiteson?

  We really would. We want to know what questions you have about this extraordinary universe.

• 57:56Kelly Weinersmith?

  We want to know your thoughts on recent shows, suggestions for future shows. If you contact us, we will get back to you.

• 58:02Daniel Whiteson?

  We really mean it. We answer every message. Email us at questions@dandkuniverse.

• 58:09Kelly Weinersmith?

  Or you can find us on social media. We have accounts on X, Instagram, Blue Sky, and on all of those platforms, you can find us at D and K Universe.

• 58:18Daniel Whiteson?

  Don't be shy. Write to us.

• 58:25Speaker 01

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