Why Science Says Men & Women Will Never Be The Same - David Geary

you can take a brain pattern of a 10 year old and predict whether that brain belongs to a boy or a girl about 93 percent of the time almost as good as you can by looking at an adult face of a male and female so huge difference why do you think the discussion about sex differences between men and women has become so hotly contested recently yeah great great question I I think it's always been hotly contested to some extent um it just kind of flares up and then down just depending on conditions I I I think the the one of the main drivers is there are um many individuals who don't want to believe that there's biological bases to anything and if there's a biological basis to anything it it's going to show up in in sex differences and there are um gender activists who don't want to believe that there are differences between men and women that have a biological basis to them and therefore they don't want to consider that those potential differences contribute to socially important outcomes like the percentage of males and computer science or engineering or you know teaching or whatever it might be and so you did a bunch of research right looking at stem uh and seeing what it was that contributed to uh women's lower participation in stem subjects right yeah so so we looked at um we we've looked at a variety of sex differences and a number of things and in one um 2018 study we looked at the um proportion of women college students who were getting degrees in inorganic Sciences so computer science engineering physics and so forth and um we plotted that against things like gender equality which is uh would be a high gender equal country would be one that they tend to be generally pretty wealthy liberal um there's high levels of female participation in the labor force there's women in Parliament or Congress or whatever um it might be a lot of women in higher ed and so forth so the standard argument has been for the last uh four or five decades is that as countries approach that type of um wealth and liberal openness that basic psychological cognitive and other sex differences will begin to disappear so so we looked at that generally we looked across countries and we found the exact opposite of that that as countries became more gender equal they were as proportionately fewer women going into these inorganic Sciences they were going into other areas um presumably so the Gap in these um these particular stem Fields actually increased as societies became more open to women participating in a variety of kind of cultural endeavors have you got any idea whether this is due to interests or abilities right probably a cup a couple of different things um interest for sure um there are sex differences in um interest in science generally and there are sex differences in particularly interest in uh mechanical um types of things how how inorganic things work um in terms of abilities the probably one of the primary movers is intra-individual strength so if you're interested so what what are you best at reading or math or reading or science or whatever it might be and throughout the world girls are generally their best subject is generally reading meaning that their comparative advantage is in fields that are more reading heavy than math or science heavy even if their overall levels of math and science are high or even higher than boys um if their strength is reading they're still more likely to go into other fields uh than than STEM related that's very interesting that it's not necessarily you could have let's say that um women were better than men in uh maths on average but that women were even more better at reading they're going to be predisposed to do the thing that they are best at we all take pride in the things that we feel we're very competent at and if we have this biological predisposition that is a sexed difference why why would it be surprising that we would go away and and flourish in those areas well yeah it is not actually surprising at all um you know in in our mind uh because it it's just a rational Choice you're going to go into areas in which you're going to have a comparative advantage where you're going to do relatively better than you would in other areas so if you're a poor reader and you're reasonably good at math and science you're probably going to go into a tech field um if you're really good at reading and much better at reading than than Tech related sorts of things you're probably going to go into Humanities or something similar why is it the case or why would it be the case that females are better at Reading and that males seem to be better at maths give me the ancestral justification for why uh men should be better at counting things and women should be better at reading things given that both of those have only been around for a few thousand years right yeah so so both reading and Mathematics are evolutionarily novel abilities and so you can't say that well you know women uh you know evolve to be good readers and Men evolve to to do math it just just doesn't make sense and you know probably if anything the good mathematicians and recent evolutionary history probably have had below average reproductive success uh you know just wild guess there um but in in terms of reading if you look at brain Imaging studies and cognitive studies and so forth it is an adaptation of the language system and other systems like theory of mind you know understanding characters and so forth understand plots um and women have advantages in certain language areas and they have advantages and theory of mind and so forth so the underlying basis upon which reading skills are developed there's a sex difference favoring girls and women when it comes to math uh there's no math Gene per se I mean there is a kind of inherent sense of quantity and so forth but it's not a very sophisticated skill um and if we look at overall mean differences in math they're pretty small where we see the differences are in areas that involve spatial abilities so certain areas of geometry solving word problems actually has a spatial component to it because you can sketch out their relations in a complex word problem that helps you kind of solve set up and solve that problem um and and that is driving the sex difference in in math levels to a large extent when when we see those differences there are also more men than women at the high end of math performance that was at one point a very big gap it's closed since the 90s so maybe three to one men than women at the high end um but it's kind of been relatively flat since then I would imagine it seems to me that the discussion around we need to get more women into stem we need to get more men in to heal has very much dampened down as the Stark difference in College admission and then uh like completion rate between women and men with two women for every one man completing a four-year us college degree ish on average seven times more men dropped out of college during covid than women uh it's it's huge um I noticed that the discussion around uh pushing women further into higher education appears to have kind of Fallen by the wayside we haven't we haven't had that uh be quite so vociferous uh as it was and that seems to have been I would have said in the last sort of three to four years uh that I've really noticed it yeah yeah the um you know if we go back that there's a long literature on um kids liking of school you know going back more than 100 years and and girls have always kind of liked School more than boys um sitting there listening to adults and you know being conscientious doing I mean that's more uh it's easier for girls to adapt to that kind of environment than it is especially for young guys they just are not really it's not really their thing um and as higher ed opened you know there there were clearly restrictions on in discouragement of women going into college um going back 60 years or so is those restrictions abated we had more women flowing into higher ed than men and now we have about a 60 60 40 ratio of completion um for uh in in the U.S and a lot of um Western countries yeah so bringing attention to that um highlights the disadvantage that boys and men now have in educational outcomes and that might be why um you don't hear as much about it because um the gender activists don't want people to think about it but it's it's a problem it's a problem on multiple levels one is it's distorting the operational sex ratio for young adults more educated women than men leads to more competition among women uh for a smaller base of educated and ambitious do you know what I've I've deemed that I needed to come up with a meme to describe that so I've deemed it the tall girl problem tall girl problem yeah yep and it's um you know it it's associated with the delays in marriage um you know increased divorce rates uh more objectification more sexy selfies more casual sex more unprotected sex right right you know back back back to the hippie and disco days types of things for young educated um adults yeah you know which is whatever I I used to blame it on the Bee Gees but apparently it's a little more complicated than that you know you've got the the sex ratio uh thing or or or the tall girl thing tall girl problem it is yeah the other problem is is that um the US and and a number of other highly developed countries are losing the industrial base that would um provide pretty good paying jobs for working class guys that really got them integrated into the uh Workforce integrated into the broader culture so forth and now a lot of those jobs are disappearing and you have a lot of guys that are probably pretty good at spatial mechanical types of things but they're not pursuing school and a lot of them are pulling back is a huge number work you know living at home still not really engaged socially not engaged economically and it you know it it's a potential Tinder Box for society if if you know things really really collapse economically you are touching on all of my favorite catastrophes and crises here David so first one um Richard Reeves book of boys and men were you familiar with that did you get to read that last year I don't think I I've read that you would it's very short super short read only about 150 200 pages I think fantastic so it's um here's a policy wonk guy from Washington DC who is looking at structural issues that boys and men are facing uh education employment and then in the home you would love that so first off put that on your list secondly Nicholas eberstat men without work are you familiar with him no no yeah I I yeah sorry I I've read the basic economic papers but not the popular press books got you yeah so his um he was on the show a couple of weeks ago and he said there's this cohort of prime working aged 22 to 55 year old men seven million of which are unemployed and not seeking work on average they spend 2 000 hours per year Watching screens 50 of that time is on prescription drugs or whilst smoking weed and two-thirds of that cohort live in a household which claims at least one disability benefit right right absolutely wild huge huge problem uh that is a huge problem I mean partially due to the changes you know increases in world trade and changes and as I said that the manufacturing base um I I also wonder if a lot of the cultural social rhetoric about things like toxic masculinity and so forth and promoting girls in education which is fine um but it's often seen by activists as a zero-sum sort of game you don't want to acknowledge any issues that boys have because that might take away from what girls are the extras that girls are getting and it's creating a real problem I couldn't agree more um one thing that you touched on before was the potential Tinderbox and uh let's roll all of these together given the fact that we have the highest rates of sexlessness amongst young men that we've ever seen around about 30 of men haven't had sex in the last year aged 18 to 30. around about 50 percent of men say that they're not looking for short-term or long-term relationships we have this massive cohort around about seven million men just in the US 22 to 55 that are not looking for work not um and also not employed also not in education employment or training and yet we haven't seen the in-kind increase of killings and anti-social Behavior spray painting cars setting stuff on fire pushing over granny Etc right what do you attribute the fact that young male syndrome has all the raw materials to occur and yet we haven't seen it what do you think is going on there right yeah yeah well typically as as you said when you have these disaffected disengaged men you get higher rates of crime and violence and a variety of other um social ills I I think you hit on it I mean they have something to keep them occupied they've got internet porn or whatever they're watching on on the screens and they're getting some flow of income either from disability payments or extended unemployment or they're living with their parents or something like that so they are kind of marginally satisfied probably with with things but um you know what happens if you know the US and these countries go into a massive recession and these benefits and other sorts of things have to be cut and you know it's basically they're being paid off uh to be quiet and just deal with their situation oh that's a very interesting way to frame it there is um some existential malaise just this ambient sense that you're not needed uh structurally socio-culturally uh archetypally in terms of the role that you play in The Wider World um and the how would you say Rich social safety net financially that a lot of men are offered it doesn't allow them to buy a palace but it gives them enough money to keep the pawn uh subscription and the internet taking over uh which means that social media can continue to sedate Video Games Etc Etc yeah I think um right where I've arrived at is a sedation hypothesis that you've got porn video games social media that are kind of um nursing the desire for status seeking for goal orientation and for reproduction and giving them a titrated dose this is enough means that they don't need to go and do it therefore the lack of it doesn't hurt quite so much it's not enough to be satisfied but it's enough to not go and burn everything down um foreign I mean this is the this is a problem that I'm I'm basically completely obsessed by at the moment um one one other thing to to just kind of round out what we spoke about at the beginning is that the gender equality Paradox is that what we're referring to the fact that as you get increasing egalitarianism you have more of a sex difference in terms of what people go into right yeah yeah so so that we we call it the gender equality Paradox and stem uh in this particular article um but you also see larger sex differences in a variety of other things such as personality spatial abilities uh a variety of things that it you know as people get wealthier and there are more options social and economic options available to them um they're better able to express their own individual preferences and we've argued that as you're better able to express your own individual preferences any inherent sex differences or any inherent individual differences will be better expressed in those contexts than his contacts that re that um uh have for a variety of reasons more restricted opportunities so as the real world constrains your choices less by being more free more open more degrees of freedom more opulent Etc that allows you to fully follow whatever it is that you care about the most therefore these sex differences we seem to see increase right yeah what is the response from sex difference denial groups about why the gender equality Paradox exists then well um yeah when when we uh uh he's so Ed and I did this you know that this 2018 study you know I I we walked through got through all the data and we thought it was pretty interesting but not you know we didn't think it was going to be as big at least I didn't think it was going to be as big of a deal as it turned out to be mostly because it wasn't that surprising and it wasn't that surprising because other people had found like increases in personality differences and so forth across cultures um but our uh but the response to it was pretty um negative we we got a lot of emails um the editors of the journal apparently got a lot of emails including um you know attacks on us and pressure for them to retract the article so forth they they didn't do that um there there was a commentary on it that did get published I think just because the editor got tired of getting so many commentaries he finally say well we're already published one and we're not gonna do any others um that showed that the gender equality Paradox didn't well one they they complained about how we Define proportion of males and females in stem fields which was just kind of kind of dog you know I I know you know just kind of a stupid thing um but then they took actually in a study that he's born and I put together called the the biggie which was an alternative um measure of well-being and sex differences and well-being rather than the gender um equality measure that most people look at we looked at things like opportunities to complete education overall healthy lifespan life satisfaction things that are um equally valid for men and women and boys and girls rather than something like the proportion of women in Parliament which has a gender activist and it's it's very female biased so when we use the female biased measure which is what the activists push for and is a better measure of gender equality we get the Paradox when we look at our measure which we developed to make it sex neutral just because the gender equality stuff is biased um they don't find that which is what we we would expect but in anyway the authors of that made a big deal of that they did a hit piece on he's bird and eye and BuzzFeed um oh very reputable academic response there yeah I I had never read BuzzFeed I never even considered it you'll be parked in between four outfits to wear on your next hot girl walk and 10 dog memes so good that we can't stop laughing so I'm glad that they really positioned you appropriately that right right well they they put in there a lot of AD homine and a lot of comments that the editor and reviewers of their comment to the journal said you got to take out because this isn't supported they put it in there but anyway now there's this BuzzFeed thing and there's this uh commentary on our original article so when people bring up the gender equality Paradox and stem you they can now say well this has been debunked see this BuzzFeed see this [ __ ] off dude [ __ ] off yeah yeah yeah yeah so that's that's how it's dealt with you know you get something into the General Media in a commentary somewhere or some counter argument somewhere and then when somebody brings it up you don't have to discuss the points you can just say well that's already off the table it's gone it's been uh you know the top speed at Al 2018. yep yep phenomenal okay um one final thing to sort of round this out you've used uh the participation in stem that seems to be you know a very obvious sex difference that occurs as you get more egalitarianism in in a society are there any other equally strong or even stronger evidence for the gender equality paradox well uh one one interesting thing is the um sex difference in height gets bigger um what which sounds weird yeah yeah and that that has nothing to do with gender equality actually it has to do with the overall health of the population the wealth of the population medical um yeah oh so using in a in a less prosperous uh less egalitarian society or a less prosperous Society egalitarian societies tend to need to be prosperous in order to be able to allow people to choose what they want prosperous societies have better medical interventions Food Water Sanitation Etc which doesn't Nerf the height increases that men's natural genetic disposition would have caused them to get am I right here that's correct the physical sex differences get bigger um because the overall health of the population gets better and so not only are the psychological sex differences expressed better the physical sex differences are actually larger that that's a very robust effect and I'm looking now at whether that particular fact is correlated with changes in sex differences in certain cognitive abilities suggesting that as physical health gets better you know the brain obviously is going to mature better and fully developed to its full potential um then some cognitive sex differences should actually increase along with the sex differences and height and um it's hard to study that a little bit because there's really good data on height across you know the last century in a lot of countries and some places across multiple centuries um but the you know the psychological cognitive tests are more recent so there isn't as good a data but but but there's hints of that um the spatial advantages of men in spatial abilities seems to be increasing along with their increases in height and the and and it and it often is uh positively correlated with um the overall health of the population so healthier populations with bigger sex differences in height usually have bigger sex differences in um spatial abilities uh the same seems to be true with women's advantages in certain verbal memory tasks and episodic membrane personal experiences and so forth they're better at those and as indicators of overall physical health get better um the sex difference there seems to increase as well so that ties it into if we tie it into height changes um we can better link it to actual an actual biological mechanism David you're absolutely blowing my mind here this is so interesting so um in the same way as a prosperous society allows men and women to better choose the life path that they have it may also um biologically nutritionally medically Etc create a foundation that allows men and women to be more of what they are with regards to their cognition their capacity uh their behavior which is Upstream from a society that allows them to choose what they want to do more so it predisposes them to a particular type which would be women I I imagine you know if you were able to do the best studies in the world you might even find that women's social networks become more intricate they become um more nuanced and more subtle in particular ways um this is like this is one of the most interesting things that I've learned this is really really really cool um yeah they're they're there are some interesting Behavioral Studies looking at um in developing nations looking at things like um uh Nutritional Health nutritional supplements for kids who are um at risk for stunting you know kind of low physical growth poor poor physical growth and so you can look at behavioral competitiveness um physical activity levels which generally favor boys over girls and you can look at you know how to supplements you know how does improving their health change these sex differences and Rough and Tumble play competitiveness and so forth and the biggest gains are for boys who are receiving these supplements and um the biggest losers are the boys who don't get them so some of the sex differences in you know just physical activity levels and and competitiveness um are smaller or disappear in malnourished you know poor health kits but when you improve their health these sex differences pop up that's fascinating yeah yeah consistent with you know there there's a biological Foundation to this that is rooted in um you know physical health in including um you know brain development when it comes to sex differences in cognition what are the most well-established differences in men's and women's Brains let's get into the nuts and bolts of what's actually going on here sure so let's um you know traditionally psychologists have been studying sex differences in cognition for you know a century or so um and they focused on verbal abilities generally math and spatial let's take math off the table because it's evolutionarily novel it's not that interesting and inverbal is a Big Field it can go anywhere from you know how quickly you can name animals that start with the letter a um versus analogical reasoning you know girls have advantages and one Boys on another so it's it's not not clear so putting it I I've argued that we you know we really need to think about these cognitive sex differences from a broader evolutionary perspective and think about okay what is it that is universal um across people no matter where they live you know math isn't because you get it in school or you don't get it at all um and so things that are one thing that is universal that women and girls have advantages on or something that I call at least an aspect of folk psychology these are skills that allow you to interact with individuals on a one 101 basis and more importantly develop and maintain one-on-one relationships this would be you know BFF sorts of relationships you think about all the skills involved in that and that would be you know language is obviously a good part of it but also reading facial expressions you know making inferences about how they're feeling or thinking based on facial expressions reading body posture types of things vocal intonation theory of mind which is your skill is actually figuring out what's going on with the individual and if we look at each of those individual skills girls and women have small to moderate advantages in them but in the real world they're working in concert they're not just bits and pieces they're they're working all together and if we look at the entire constellation of skills as they're working together in an interaction or interpreting an interaction girls and women have fairly large advantages probably about 85 percent of them are better than the average guy or maybe 90 or so so it's a fairly substantial Advantage there are other areas involved in you know dealing with with people or groups or whatever where we see more subtle differences but it's the the one-on-one kind of emotional intelligence I think some people might call it that I think that's what people mean by that I call it kind of an individual level folk psychology girls girls and women do really well at that um boys and men do particularly good on what I call folk physics this is is not an academic physics but it is kind of the foundation for aspects of of an academic physics it involves things like um dealing with the physical world uh navigating from one place to another tracking the trajectory of things as they're moving um through space um understanding how objects might be manipulated and used as tools a mechanical reasoning type of thing and so boys and men um have small to large advantages in in all of those areas wow okay what social learning theory social learning theory well there is a social learning theory where we learn to um you know what do you do in this context you know you go to a dinner with folks you know it's your first formal dinner you've never worn a tie before and you have no idea how to do things you know you watch other people and you figure out you kind of imitate um what people who seem to know what they're doing are doing and so that's a social learning type of thing and and and that's a universal as well I mean we learn a lot from other people there's no doubt about that but I I think it might be mean social roles theory yes yes yeah so social roles is the um argument that uh boys and girls and men and women learn to behave in sex specific ways you know like girls are more communal or nurturing and guys are more agentic you know focused on getting things done being more dominant and and so forth because they receive either explicit or implicit information from the social environment that they are that basically tells them oh you're a girl you're a boy and this is what girls and boys do and therefore you adhere to these roles and the argument then is that um that's how all these we're basically Blank Slate mentally psychologically and then we kind of develop these roles based from you know learning from others of of the same sex um and that is the argument underlying things like um you know encouraging girls to do this getting Role Models you know girls in stem Role Models which is fine I mean whatever um the problem is is it's it's well overstated you know boys don't like playing with toy cars and blocks and so forth because their parents have implicitly given them those toys for Christmas or they've seen the advertisements you know boys playing with these things on television um they like playing with these things because uh you know if you're playing with a car it is it has a specific type of motion to it it's a non-biological motion that captures the attention of What's called the dorsal visual stream that feeds into these folk physics centers that I um mentioned uh previously so there is an early bias in what boys and girls look at boys look at physical motion and stuff and they're attracted to those types of things girls look at faces and the details of objects more and that's I mean there there is some place for social roles but but it's the extent of its influence is really overstated in my opinion a lot of people when they talk about sex differences particularly whether that be in children or as soon as people grow up to be adults will come up against somebody who either in terms of well-meaning or this is just the way that they see the world will use social roles Theory as well look of course boys are stronger than girls they're the ones that are encouraged to do Rough and Tumble play of course boys are more interested in things than people because they've seen it on TV of course boys are expecting to be more dominant because these are the subtle cues that their parents and the media and everybody else has given to them for the people who sit down at Thanksgiving perhaps with that one brother or sister or cousin who makes it puts this across as an argument what are the strongest rebuttals that can uh dispel this particular myth yeah so so there was well one these differences are um Universal I mean it's not just you know the you know us upper middle class families at Sea I mean you see it all over the place um but but one important piece of data well there are a number of them I'll tell you one and I'll tell you more if you want um there was a study done you know a few decades ago that was a fairly large-scale study looking at um you know a couple hundred parents and how they were socializing their kids so there were some of them were traditional parents you know they'd buy the girls Barbies or dolls or whatever and the boys you know car trucks and other parents were more um I don't know if they'd be Progressive I mean they'd be called Progressive today that back then they were hippies or whatever they were they were they they were non-traditional so they raised their kids say okay you know girls can play with with blocks and with um toy cars and boys can play with dolls and all that's fine it doesn't make any difference and then the researchers brought the kids into the lab setting and said okay is it okay for girls to play with trucks and boys play with dolls those that were raised in non-traditional families said yeah yeah sure it's fine no problem so their beliefs about what's okay and or what's typical or not typical or whatever uh mirrored to some extent what their parents said um but then when you cut them loose and watch how they actually play they still play in sex typical ways so their beliefs about kind of what boys and girls should do and their actual be it was one thing but their actual Behavior was sex typical there was no difference between how boys from traditional and untraditional families played and same for girls meaning that the kids are calling the shots here um they're creating their own environments based on what they find interesting and what they want to do does this show up in primates as well juvenile primates yeah um Rough and Tumble play is um pretty common in species where males are bigger and more aggressive than females and those are typically species if we're looking at primates where there's a lot of male male fighting and competition in adulthood clearly see that in humans if we look you know in human history it's clearly a lot of physical competition a lot of violence and and so forth um the sex differences in physical size go back at least four million years in our ancestors it's a long long evolutionary history of that obviously males and females are big males are bigger than females and modern humans and we see the sex difference in um Rough and Tumble plight I mean it just fits very very nicely with this evolutionary pattern in this pattern of uh male on male aggression I remember hearing a while ago that if you give a juvenile female chimp perhaps a sort of a soft toy that resembles a baby that they treat it in a different way to the males is that right was that have I made this up or was that correct that's that's correct it was with vervet monkeys and I think it's been replicated in you with with macaques or so so right if if you give toys you know sex typical toys the human sex typical a doll in a truck you know big like dump truck that that they they can play with um you do see preferences the the the females like the dolls more than the males do um the males are also more likely to approach their novel types of things and so they're risk-taking um is higher there now there's no um you know toy trucks and macaque evolutionary history um but again it it could be attractive because of the type of motion in the dorsal ventral stream associated with navigation and just kind of focusing on large-scale space I'm fascinated by the fact that um the type of toys it's not it's not just the fact that that figuratively represents a kind of uh role perhaps that I would imagine that if you were to look at the sex differences in the trucker community that it's going to be heavily skewed toward men um but it's there's also something innate about that movement back and forth and given the fact that we you know go back far enough and we do have a common ancestor there has to be the sex difference which at least was maybe there before we split off and we're seeing this play out with macaques or whatever else it might be um what what would you say to the people that say we are more similar than we are different you know if you look at the overlap between the dispositions that boys and girls have that men and women have um you know you've mentioned there at one particular example which seems pretty Stark which is the average female is better than 85 percent of men when it comes to I think it was reading faces or perhaps it was verbal ability um what would you say to people that say we're more similar than we are different these sex differences are basically small and it doesn't really matter and David you're just making a mountain out of a molehill yep yep yep um I've heard that and and that's a very popular belief in um in in the field and in one that is debated so if we look at sex differences in certain verbal skills they're fairly small so you can say well we're more similar than different maybe 60 percent of women are better than the average guy um not big but my point was in in other people's point is is if you put the whole package together it's you know the brain is an integrated system of uh you know that pulls together abilities that you use in Tandem and when you pull together these networks of abilities that it would include you know making eye contact uh theory of Mind sort of things vocal intonation and so forth that's when you get very big differences and that's kind of more of a real life sort of thing so if if we look at individual personality types of things like um how sociable how much you like just you know festive chatter and talking to people in kind of the warmth component being nurturing you know it's a modest sex difference favoring girls and women in this case um but if we put together the whole pattern of Personality we have much much larger differences with not in this case not much overlap uh because this is not just like rolling a six once it's the equivalent of rolling five sixes in a row and that Suite of traits when bound together Trends much more towards women I had um I had Joyce Bennington on the show at the start of the year and she gave me a really interesting example I'd love to know if you've looked at any of this she spent forever uh studying kindergarten kids playing and the games that they play and she mentioned that if you look at the sorts of games that boys and girls play these are uh three four years old I think maybe up to five years old you know hasn't been a massive amount of time for socialization to occur especially in kindergarten this may be if you're the eldest child or an only child the first time that you've actually got to spend any significant period of time with other kids and she said if you look at the language they're using if you look at the games that they're playing boys are um binding themselves together over shared Warfare against Cowboys or aliens or something else and if you look at what girls are doing they are keeping something alive it's a rabbit it's a doll and the language as well that's used is um again very different sex differently what have you have you integrated any of this the sort of social game playing into your work too yeah yeah yeah yeah of course yeah Joyce's work is great I I really keep up on it and uh like like reading it yeah in um yeah that's uh called social dramatic play yeah so kids when they hit that age begin to develop a richer imagination so they can now imagine themselves in different role-taking sorts of um you know uh you know different characters in these roles and then they can now better integrate their roles with the roles of their Playmates so they're they're basically practicing social interactions in different contexts being you know the hero of being a parent or whatever it might be so it's it's an important component of um development and the interesting thing there is that the fantasies that boys and girls as as Joyce stated uh develop on their own um differ quite quite dramatically and uh in fact the the vocabularies of boys and girls begin to differ in the second year of life in terms of what they talk about how so what do they talk about you know so you know a stereotypical things uh you know unsurprisingly to me so 18 month old girls are more likely to focus on clothing um and boys on um objects and you know in terms of just kind of free free discussion sorts of things but but the boys integrating themselves into a they typically integrate themselves into larger groups Joyce probably talked about this as well and these groups as you said are in some type of conflict with something you know the Indians or dragons or whatever it might be and they they're coordinating and integrating their behavior together that is in my opinion a component of rough and tumble play I mean there's individual Rough and Tumble play but there's also coordinating your activity so that you are more functional as a group and if we look at um between group conflict and traditional contacts and we look at it historically it is coordinated activities of males fighting the coordinated activities of other groups of males that's male male competition it just goes beyond one-on-one it goes to a group level type of thing and these early play differences that Joyce talked about we've wrote about 20 years ago saying that this is preparation for this the boys are creating these groups because these are the groups they're going to grow up with and later in some cases fight with or cooperatively hunt with it makes complete sense to anybody with a semi-functioning brain as to ancestrally why boys males would have this predisposition for practicing Warfare and why girls would be interested in people they would be playing doctor or drama or veterinarian or whatever family how does this manifest or what what is happening that's causing this to manifest we can understand why right we can understand the ultimate reason for why this is happening but what what is it that's inside of a male that causes him to think let's pretend that we're fighting Cowboys yeah they don't they aren't necessarily thinking anything they're engaging in things that they find fun so if if we look at disorders or just individual variation in either prenatal exposure to testosterone or um uh postnatal spikes the first six months of Life there is a big spike in testosterone so there's a second dose there in addition to the prenatal dose and and girls have some some fluctuating exposure to estrogens during that six-month period as well although it's not it's more variable than with guys but in in any case um the these hormonal influences are at least partly contributing to these sex differences in play so girls who have more had more androgens early in life uh you know prenatally um engage in have play behaviors that are closer to boys than girls or they're they're kind of in between those so so it's a mix of of activities so there there there's clear the hormonal component to it and I think the way that works is in terms of what captures your attention you know biological motion is probably going to capture the intention you know of a baby or something will capture the attention of girls more than boys whereas the you know the physical motion is going to capture the attention of boys more than girls all you have to do is have kind of a small attentional bias and built-in reward systems that will kind of keep you focused on that and keep you engaged in related activities and then it can kind of build from there so that the mechanism is heavily driven by Androgen exposure to testosterone primarily and that's one of the key differences is there anything else going on here is a protein folding in the brain are there particular areas of the brain that are um larger smaller atrophied you know hypertrophied in in one form or another yeah I mean probably probably the there are I mean there there are sex differences in in certain very basic areas of the brain associated with aggressive sexual and and that type of behavior um and there are some really interesting sex differences in overall patterns of brain organization so if you look at uh gray matter and white matter if you look at one small part maybe there's no difference or maybe there's a difference and if there is a difference it's probably not going to be huge on average but if you look at the whole pattern of the brain um you get quite substantial differences you can take a brain pattern of a 10 year old and predict whether that brain belongs to a boy or a girl about 93 of the time almost as good as you can by looking at an adult face of a male and female so huge difference and that's fmri that that would be MRI just just structural differences what what people really need to look at is the um coordinated activity of brain areas so certain brain areas that are linked together are going to fire together spontaneously and that kind of helps build that Network and um uh keep it kind of well functioning so if you look at those spontaneous brain activity studies and there aren't that many with really young kids yet but there's at least one during the prenatal period where you can put Mom in a scanner and get a brain activity indices of the fetus and we see sex differences there in brain activity patterns in about six months prenatally um and there there was a recent study looking at um I think was two and three month olds also showing uh differences in in spontaneous brain activity patterns but exactly how those are related to some of these sex difference we were talking about we we don't fully know that yet if it was 93 to 10 years old what is it at six three months prior to birth and six months after birth yeah they they didn't do that that was a somewhat different technology and approach and they didn't do those particular analyzes probably it's going to be smaller because probably the differences get bigger um with age but but they they didn't look at it yet I think nine or ten is the youngest that I've seen look at that there there's a number of these studies with adults and it gets up to 95 or so do you know how accurate they could be at predicting the sex of the embryo though oh yeah they they didn't do those analyzes okay okay fine fine um evidently what the researchers are amongst another a number of things trying to achieve here is say well at age nine and ten you have had you know social social roles Theory comes back in again perhaps you have been socialized into a mode of thinking which has caused structural changes in the brain these structural changes then basically beg the question by being the detector thing that is supposed to be detected and people say that's what a male brain looks like because we have never seen a male brain which hasn't been socialized as a male brain despite the fact that there are a wide variety of families that raise children in traditional and non-traditional Progressive and non-progressive ways unless someone is going to say somehow that the brain of the embryo three months prior to being born has somehow been socialized the sex differences that we see and you know I'm being uh like overly um explicit here to just really try and Hammer the point home that there are structural changes that manifest into real world significant differences not only in disposition not only in um uh tendency interest capacity um there are it's a whole Suite of things that occur and um David Buss mutual friend of ours was recently on Rogan and I knew I had it it was absolutely adamant that uh Rogan was going to bring up sex differences sure enough as as was predicted that ended up happening the most interesting thing that I've learned about sex differences in the last year is differences in throwing accuracy amongst children can you please red pill everybody that's listening on the differences in throwing accuracy amongst children sure so um yeah so you find differences in throwing accurate see throwing distance and velocity so uh even in preschoolers boys are throwing more uh they can throw farther um in with higher velocity higher speed and so higher kinetic energy than girls can uh it is it emerges very early uh as I said the preschool years and becomes extremely large by 19 early adulthood or so where there's very little overlap between uh men and women maybe a little bit but not not much it is it is a very big difference it is correlated with um differences you know the shoulders are built differently the forearms are longer in men relatively uh relative to overall size in women that um that difference is evident prenatally it is associated with the sex difference in this dorsal stream sort of thing the ability to track moving objects you know to hit something that's you have to have the cognitive system in brain and cognitive system in place in order to hit something accurately um and if somebody's throwing something at you you want to be able to track it coming in so you can dodge it oh yeah it didn't you looked at a study to do with how effective males and females are at dodging projectiles coming at them what can you tell us that study yeah so um some people have argued that or in fact the initial argument and maybe it's still the argument that the male advantage in throwing distance accurate speed and all of that sort sort of thing is due to Shared child care and male hunting um you know and of course there is a big sex difference in hunting engagement in um in in traditional context no no question about that um but in addition to that men are better at dodging things so in this particular study uh you couldn't do it anymore but but the the researchers I if I remember correctly got one of these tennis ball shooting machines um and uh decided to shoot him at undergraduates um to see what would happen I'm sure the professors had a fantastic time when they were aiming it at the annoying child in the the front row that keeps on distracting them during their lectures yeah yeah yeah would unfortunately we can't do that anymore um but it I'm I'm sure it was at fairly low speed and you know so nobody would get hurt and so if relatively easy task and so they just looked at the number of balls that could be blocked and Men blocked most of them in fact there was a ceiling effect um in women were not as successful uh at that and that's obviously a defensive mechanism if other males are using projectile weapons the ability to track and Dodge that is an important component of male male competition that's that's when my argument's not which came probably before hunting what is the suite of traits that we're talking about here when it comes to throwing accuracy throwing velocity dodging seeing things moving through the air Etc yeah so yeah so so we have the throwing component to it it has you know the behavioral component actually throwing something and hitting it accurately um it has physical components to it you know the upper body upper body strength is big sex difference there the architecture of the shoulder and arms there are um there's brain area associated with motion detection and integrating motion detection with physical movements as in blocking something or throwing something uh and so there's brain and cognitive systems involved there um that you see physical systems the behavioral component of the brain and cognitive component and guys are better on all of those components or at least the most of them integrated together um you get a quite quite a large sex difference so this learning that and it was specifically the accuracy thing that really drove it home to me uh is for me now one of the more compelling justifications for for us thinking about transgender athletes in sport a lot more carefully because everybody has heard to death uh someone talking about how a biological male shouldn't be able to step into the ring with a biological female after a year of estrogen and testosterone suppression and then punched their face into the ground like you know that's it's self-evident and a lot of the arguments that I've seen stem exclusively from well we can reduce Power by x amount by putting them on this particular type of hormone blocker testosterone and androgens aren't all that drive power then someone comes back and says well look at bone density look at muscle mass look at all of the time you've gone through puberty blah blah blah that's that's done like it's interesting I guess it was interesting but it's no longer interesting to me what is much more interesting to me are the fundamental capability differences especially when it comes to things like accuracy because if let's say for instance that you were to have a biological male that is going into the uh what is it the baseball Envy NBA no what's the what's the baseball league called is there a women's lead yeah well there must be I'm oh yeah I've got to imagine so but the same as a WNBA right okay so let's say that male goes into WNBA they're not taller they're not bigger they're built the same uh on average as the average female basketball player because I would imagine that female basketball players probably pretty tall taller than me taller than you um but what we're saying is that there is a fundamental capacity capability difference that biological males have with just the way that they see throwing and spatial rotation generally not just to do with the physicality of the architecture of the shoulder changes in forearm length Etc but the the way that their brains are able to see the world of throwing overall this also explains to a degree why the WNBA may be significantly less popular than the men's division not because women are smaller and something else and something else but they have a predisposition that is oh you could say um that male's capacity is overclocked uh and it is um supercharged comparatively with women so this to me is the most or one of the most compelling reasons because it gets Beyond this sort of messy conversation about power and it gets more into fairness uh and it's why it's so compelling and I've never really heard anyone do a full Treatise on on this area of transgender athletes in sport what is it let's say that there was a sport um where you had to do line detection or you had to manipulate different social groups or you had to be able to detect facial cues or something uh if you were to have female to male transitioners in that sport they're going to absolutely dominate The League even if they have taken testosterone for ages and they're walking around with the socio-sexuality through the roof and the the sex drive really high or whatever I I just found this it's really fascinating I think this is really really interesting stuff yeah yeah yeah some some of the spatial differences and the perceptual differences that I mentioned are more strongly related to prenatal or an early postnatal hormonal exposure than actual circulating testosterone so you can the men's circulating testosterone isn't really highly correlated with their spatial abilities but the earlier exposure seems to be what's important there so yeah you can decrease muscle mass a little bit by reducing testosterone but there's other things you're not going to change that people have as you said people haven't talked about how big are the differences between navigating from one place to another yeah good good question um they are I I would say they are um you know most of them are kind of contrived situations you know they're moderate to large I would say men are better you know just kind of dead reckoning sort of thing you know you start from some place and you wander around in the woods and then you try to figure out how to get your way back without you know explicitly just backtracking the exact same way you were get the quickest route back men are better in that I don't remember the exact effect size but it's it's it's it would be noticeable um difference uh map Reading is different as well interest in maps is different we could see uh quite obviously why it would be the case that men need better spatial rotation they need better navigation over a broad ranging kind of distance because if you're going out and on average men ancestrally hunted more than women therefore wildebeest goes from right to left I have spear wildebeest plus spear plus throwing plus trajectory plus how the [ __ ] do I drag this back home hashtag where is home as well also what about female um sex differences that give them capacities that men struggle with and also why would these be that what is the evolutionary justification for why they would have them yeah so so the sex differences and the folks psychology or emotional attention uh emotional um intelligence that I talked about earlier uh women have advantages in um probably related to a couple of things one of them is uh uh women are and girls want to develop a social support network that for social emotional support and social and other types of problem solving men form networks as well but they're usually task oriented or competition oriented networks so if you hang out with all your friends watching you know the WNBA or the Super Bowl or something maybe the Super Bowl will be better watching the Super Bowl and you were this last time rooting for the Chiefs all of you and they win you're all kind of bonded together even if you didn't talk about anything during that time you drank beer and did whatever you're going to do that's kind of a shared activity um that kind of helps link male groups together and you can have lots of guys there you can't you know doesn't have to be limited to two people um girls and and women form relationships more based on the dyadic interactions and the social and emotional support talking through issues talking about what's important to them and so forth and uh the the Dynamics of this are very different between males and females I I covered in my um my book on on sex different differences but one component of it is that to develop and maintain these BFF relationships you have to be very sensitive to the emotional state of um your girlfriend your your best friend you have to read things and so forth she may not want to really bother you by talking about you know problems with their boyfriend or Mom or whatever that might be but you can pick up that something is not quite right and you know a lot more about her than guys do about their friends saying oh you haven't trouble with your mom again is it such and such a sort of thing so that's the theory of Mind sort of thing you're picking up subtle non-verbal cues picking up on it that's exactly what the girlfriend wanted you to do and that engages you in in the talk that that hopefully will help to resolve um that type of issue so that emotional intelligence is really important for these relationships it's also important for dealing with and matting out something called relational aggression so the movie uh Mean Girls maybe maybe you've seen that so you know kind of kind of [ __ ] um girl you know subtle put Downs um gossip and spreading lies it it's basically designed to disrupt the um social networks of competitors undermine their same-sex friendships and make them unattractive to um boyfriends that would be boyfriends and it is most effective if it's done in a way that is plausibly deniable that is you do it very suddenly you know I'm really worried about so and so because I think she's seeing three guys or drinking a lot yeah that that sort of thing and so because it's more you know when guys are mad at each other they'll make eye contact and they'll push or yell I mean you don't have to figure it out I mean it's usually obvious um if they're really upset but you have to have these subtle social skills to pick up on that relational aggression so that you can counter it um and so I think the combination of relational and and also have these subtle skills to use it to manipulate other other people um I think the combination of the the social support friendships and the competition female female competitions relational aggression is really um the basis for the female advantage in these these skills it seems to me that the heavier brow Ridge that men have the bigger jaw the bigger hands these are our weapons right this is how men would have done their intersexual competition it would have been uh into group Warfare as well with different tribes etc etc the ability to understand and manipulate social dynamics language ability reading facial expressions that is female Weaponry in regard now it's also defensive offensive uh affiliative um you know coalitional all of that um but I just I loved thinking about conceptualizing things in this way that because women on average weren't getting into physical altercations because they are more fragile sometimes could be with child if they die the danger of the child being on their own is significantly higher therefore make sure that you don't uh how would you say explicitly obviously accusatorly do something that could cause you to be on the wrong end of a very sharp stick from either the husband of the woman that you just pissed off or the woman herself right so you need to be able to manipulate social groups you need to be much more subtle and you need to dance your way through this you need to use coalitional uh tactics you need to sow seeds of Discord venting as an example of this um and because of that you have to have a predisposition you have to have these capacities to be able to make yourself capable whereas for men everything's out in the open you got a problem let's sort the problem out we don't need to have that quite so much um yeah yeah men men engage in relational aggression too and they play politics and some of them are very good at it but the politics is to organize large-scale groups for a collective actions sort of thing rather than manipulating the social dynamics within a smaller kind of social um network but but but yeah you're right yeah you have to be very good at that um to navigate all of these complex social relationships in a way that doesn't provoke retaliation yes when it comes to the current trends that we're seeing this increase in transgender especially youths what's your assessment of the situation why do you think it is that we've had such a rapid increase in that happening right yeah so I yeah I wrote that qualified article that that you mentioned on that and if we look at it historically um well so what let's step back let's look at uh brain patterns that I mentioned before where you know you take it a 10 year old you you can predict 93 of the time whether it's a boy or a girl if you take an adult You can predict 95 of the time whether it's a man or a woman so the brain patterns for guys are kind of bunched up in this area but there are some individuals that kind of go out on the curve so there are guys that have female typical brain patterns not a lot of them but they're there uh and there are girls who have been women who have male typical brain patterns so it's not you know kind of out of bounds to think well you know maybe for whatever reason um you know you didn't see the sex typical shift in brain development for for whatever reason so you're going to get it would make sense that you you know you have some guys who really like girl things um but they're kind of forced to be boys and to do boy things and they would develop gender dysphoria and the same thing for some girls and so if we look at early um transsexual um in individuals they had a pattern of sex atypical play so they you know the boys are playing and liked girl things and so forth expressed wanting to be a girl had this uh dysphoria depression and discomfort with being a boy or or a girl if it's the the reverse of that in those individuals if they're carefully screened and so forth would be fairly rare but if they transition um most of them do okay they're okay with it so the detransition rates are one or two percent so it's like yeah it worked for them but now jump forward to the last you know well it started maybe 20 years ago but especially the last 10 years or so the number of individuals who are claiming to be transgender has really spiked um Way Beyond the numbers you would expect based on these brain patterns for example um and the demographics of these individuals have changed as well typically it was disproportionately more men than women and they had a history of gender dysphoria now we're getting more women especially adolescents than men and most of them as far as I know don't I mean some of them do but a lot of them don't have this history of gender dysphoria and sex atypical play patterns and other sorts of things that have historically been reliable markers of um transgender issues and doing well with with the transition if that's what they they chose to do so there's been this huge Spike as you know and it's been argued that's social media has has driven a lot of it um and I I think that's right and I argued that um adolescent girls in particular may be at risk for these negative social media influences um because during that time you know early adolescence late adolescence they're really trying to develop this social support network they're really trying to develop this you know a couple of BFFs and feel included and integrated and socially supported and emotionally supported and so forth that's a really important thing now guys go through a similar thing where they want to be part of a bigger group that works together and so forth um but the girl networks I think are more susceptible to social contagion and going along with ideas that maybe aren't a good idea just to fit in and to be part of the group and not to get excluded or rejected from the group which is a bigger concern for girls than it is for boys and I know so I think we have a recipe for like combine that with social media and all the media attention General Media attention to these issues it's now become a political signal rather than a kind of a personal desire it's like you support this because you support for all Progressive sorts of things or against it because you're against all Progressive sorts of things it's really created an environment that I think is going to be detrimental and is being detrimental to a lot of adolescents and young adults especially girls and this would explain why you have seen a sex difference in the number of f to M as opposed to M to F transitions or desires for transition because it you would presume that um there's a left-handedness argument that gets used I'm not sure if you've heard this used before uh where during the Middle Middle Ages people that were left-handed were seen as more likely to be witches so um people hid the fact that they were left-handed I think it was around about two percent of people few hundred years ago said that they were whereas now it's around about 10 to it's a teens percent I think of the population that are left-handed uh so the argument is when you stop demonizing people for being their true self being fully left-handed or being a male that identifies as a female or vice versa um that people open up that would be the explanation for why you would see this rampant increase the fact that we are more as a society more accepting of it but that wouldn't explain why you have this massive increase in F to M as opposed to M to F that's right this sect difference appears to be explained away largely by the raw materials that we went through women's desire to fit in their greater social cue ability to absorb absorb that it also explains why you don't have a completely random distribution of people across the entire United States you know one person out of every 10 schools one girl out of every 10 schools one male out of every 30 schools let's say across the US it's five girls in one class that all sit at the same table together during lunch that's right yeah yeah you see these clusters or in the one school district I think 10 of the kids um I don't remember what the male female breakdown was uh claimed to be transgender or non-binary or something which which makes no sense the the other issue that has changed is the um regret and detransition rates are going up from Fairly rare one two percent or so to um you know did depending on what you look at the stopping of of hormonal treatment can be you know one out of three or or so so the the rates of people kind of changing their mind is going up suggesting that the transgender of the dysphoria so forth wasn't really related to that it was due to some other other issue what I find particularly fascinating and kind of morbidly ironic about this situation is that the biological sex differences that men and women have are providing the raw materials to cause increasing volumes of men and women to recant their own sex or at least their own gender identity so it's almost like a supply and demand of what's going on is happening in a community of people that deny that there are any sex differences yeah yeah yeah yeah it it it it it it's a mess so right so yeah so you're you're saying that the um adolescent women's girls susceptibility to social Contagion has a biological basis to it which I I think it does um and that biological basis makes them more prone to claim that they're really a guy yeah it is um it's amazing people can can spend stories for sure David Geary ladies and gentlemen David I've absolutely adored this it's been booked on the on my schedule for about two or three months now and I've been looking forward to it it's delivered more than I could have hoped for um first off what are you working on next and then secondly where should people go if they want to keep up to date with your work right so um related to sex differences keep up I published a third edition of my book male female um came out in 2021 so it's it's pretty pretty up-to-date and I'm pretty anal about documenting things because I know it's controversial and you gotta kind of oversight things um on the sex differences thing that the thing I've been working on on and off is I have spare time you know I've uh you know other things to do is this um tracking sex differences and cognition and behavior uh as they are related to the sex differences in height so suggesting you know as as I mentioned you know populations get healthier sex differences and height get bigger if there are other biologically based sex differences or related to you know the health of the brain for instance then we should see other differences in spatial abilities verbal abilities memory abilities and so forth emerging so I work on that on I've been working on off and on on that for for a long time and it's hard to get um kind of knock out evidence for it but there's something there I I just you know the the data isn't quite there but I I I have a number of articles on sex Pacific um vulnerabilities based on evolutionary theory and basic biology that you know if anybody emails me I'm happy to send David I really appreciate you thank you so much for today great thank you thank you I I really enjoyed it what's happening people thank you very much for tuning in if you 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