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I recently made my second appearance on Ricardo Lopes’ Dissenter podcast to discuss my new book, A Billion Years of Sex Differences. We had a fun, wide-ranging conversation about the science of sex differences, human nature, and some of the most contentious debates in contemporary psychology. Here are some of the topics we covered:

• Why I’m skeptical of the sex-gender distinction

• Whether parents shape sex differences

• Whether the science of sex differences is compatible with feminism

• The largest psychological sex differences in our species

• What drives the evolution of sex differences (hint: It’s not that sperm are cheaper than eggs)

• Sex differences in career-related interests

• Sex differences in cognitive abilities

• The trans phenomenon from an evolutionary perspective

• Three approaches to dealing with sex differences: gender-role traditionalism, gender-role progressivism, and gender-role individualism

Here’s a clip from the episode, where I discuss trans and nonbinary identification:

And here’s a clip where I discuss the three main approaches to dealing with sex differences, both as individuals and as a society:

The full episode is available on Apple Podcasts, Spotify, or wherever you get your podcasts. It’s also available on Ricardo’s Dissenter YouTube channel.

Buy A Billion Years now

Follow Steve on Twitter/X for more psychology, evolution, and science.

How You Can Support the Newsletter

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In Case You Missed It…

• 12 Things Everyone Should Know About Wokeness

• The Evolutionary Enigma of Same-Sex Sexual Orientation

• Academia’s Leftward March

Psychology has always been influenced by the moral fashions of the time. In the age of “wokeness,” however, this process has gone into overdrive. According to a growing number of critics, psychology has become increasingly ideological, increasingly activist, and increasingly hostile to dissenting views.

But the counterrevolution seems to be gaining steam. More and more psychologists are pushing back against the woke turn in psychology, and trying to reclaim a more empirically based, more politically moderate, and less identitarian approach to the field.

In this post, I highlight some important recent examples of this pushback: three papers that explore and critique different aspects of the woke trend. Specifically, they look at the suppression of politically inconvenient findings, the erosion of public trust in psychology, and the growing tension between therapeutic practice and politicized conceptions of human suffering.

You might not agree with every claim made in these papers. But I hope you agree that they all raise important questions - questions we ignore at our peril.

1. Suppressing Science

The first paper examines what authors Stephen Ceci and Wendy Williams call the “dominant gender narrative”: the widespread belief that women face pervasive discrimination at every stage of their scientific careers. The paper argues that the strongest available evidence no longer supports this claim, but that researchers who point this out often face hostility or attempts at silencing, rather than open scientific debate. Here’s an excerpt from the piece.

The “dominant gender narrative” in science holds that bias against women is pervasive and occurs in every domain, including tenure-track hiring, letters of recommendation, awards, grants, journal publications, authorship assignment, citations, salaries, promotions, and teaching evaluations. Many of these claims are repeatedly broadcast despite their nullification by larger, stronger studies and meta-analyses that do not find gender bias. Because these stronger studies are cited less often, there exists a false belief among many faculty that gender bias is omnipresent in the tenure-track academy. As an example of this false belief, 248 U.S. faculty were surveyed about their beliefs regarding gender bias. They overestimated the extent of such bias in every domain. We illustrate this misalignment of beliefs by focusing on just one of the many domains in which bias against women is alleged but has been nullified by stronger studies: tenure-track hiring. We show that the dominant narrative of pervasive bias in favor of hiring men is not supported by the evidence. The reality is the opposite of what is believed, with women preferred over comparable men: multiple sources of evidence demonstrate that in tenure-track hiring in the United States and many European countries, women have an advantage over equally-accomplished men. Yet, the claim of bias against hiring women faculty continues to be widely cited in the premier science media. Challenging the gender narrative should be part of normal scientific discourse; however, doing so often evokes a backlash—as documented in testimonials by researchers who have been attacked.

I was one of the researchers Ceci and Williams contacted for testimonials, and I shared details of my own (relatively minor) experience of backlash. Specifically, I shared an excerpt from my new book, A Billion Years of Sex Differences, in which I discuss the heated reaction I received to a paper I wrote with Lewis Halsey about the causes of sex differences in STEM. Ceci and Williams quoted some of the excerpt in their piece, making it the first academic paper to cite A Billion Years.

Finally, we received a summary about the current state of affairs by Steve Stewart-Williams, an evolutionary scientist who conducts research on gender (Stewart-Williams, in press), that is worth repeating here:

“A vocal minority see positing sex differences as more than a mere social faux pas or difference of opinion, and view it instead as a moral transgression. For individuals in this camp, the idea that the sexes are naturally identical has become a sacred belief. Disagreement is seen not as an honest mistake or interesting challenge to be evaluated, but as sacrilege. And the typical response to sacrilege isn’t a tolerant appreciation of the wonderful diversity of human lifeways: ‘Well, I’m not personally into sacrilege, but if other people are, who am I to judge?’ Instead, the typical response is to censor, to silence, to cancel, punish, and shun.”

Citation: Ceci, S. J., & Williams, W. M. (2026). Organized dogmatism controls the message about gender bias in the academy. Journal of Controversial Ideas, 6, 4.

You can access the paper here for free.

The Nature-Nurture-Nietzsche Newsletter

The Truth About Sexism in Science

It’s an idea so widely accepted that we rarely think to question it: Women face rampant discrimination in science, while men coast along on a cushion of unearned privilege. You’ll hear this claim echoed everywhere, from the most prestigious scientific journals to the pages of…

Read more

a year ago · 46 likes · 15 comments · Steve Stewart-Williams

2. The Cost of Woke Psychology

The second paper argues that psychology’s increasingly activist and identitarian public face may be undermining trust in the field. According to author Travis Proulx, many people - including many on the political left - feel alienated by the discipline’s moralizing tone, unrealistic worldview, and ideological conformity. The proposed remedy is simple: less moral grandstanding and more intellectual humility. As Proulx writes:

Given the predominant role of taxpayers in funding our research, we should be concerned that the voting public may justifiably perceive our science as emphasizing activist visions of what should be over the empirical complexities of what is. Ensuring public trust will depend on re-embracing persuasive intellectual humility and eschewing the identitarian vernacular and deficit model pedagogy that currently characterizes our public-facing messaging…

Psychologists know that public trust decreases to the extent that manifest ideological leanings diverge from their own. We also know that progressive activism within our science represents views that diverge from ≈90% of the Western public – including most left-wingers. Alarming, when roughly 90% of research funding ultimately derives from a public whose enthusiasm for funding scientific research decreases with perceived social distance from scientists. Western cultural institutions are moving on from monomaniacal identitarianism, re-embracing the intellectual humility to acknowledge that it depends. Will we join them in escaping this ‘identity trap’, or spiral into an ‘Endless Summer 2020’?

Citation: Proulx, T. (2026). An ‘outgroup’ public won’t trust a progressive ‘ingroup’ psychology. Current Opinion in Psychology, 70, 102316.

You can access the paper here for free.

3. How Victimology is Killing Therapy

The third and final paper focuses on cognitive behavioral therapy (aka CBT). Authors Richard Redding, Robert Maranto, and Nathan Honeycutt argue that therapists and clinical psychologists increasingly emphasize oppression and victimhood over personal agency - a shift they fear could undermine one of psychology’s most effective treatments, and make therapy less accessible to clients who don’t share progressive political views.

Cognitive behavioral therapy (CBT) rests on the premise that individuals possess personal agency to change their life circumstances. At the same time, given growing political homogeneity within psychology, views of individual agency are increasingly being displaced by greater emphasis on conceptualizing distress as reflecting systemic oppression. Drawing on research concerning these frameworks, this article briefly examines the implications of these trends for CBT in the United States. Specifically, we outline three potential concerns, including declining interest in traditional CBT, reduced value alignment between therapists and non-liberal clients, and possible shifts in the theoretical and practical focus of CBT. We conclude by discussing implications for graduate training and the importance of sociopolitical competence and diversity in clinical education…

It would be quite unfortunate if fewer young therapists are attracted to learning or practicing CBT, given its proven effectiveness. Or, if they corrupt it through a politicization that alters its fundamental approach, aims, and therapeutic strategies in favor of strategies that serve a political agenda. This will result not only in reduced therapeutic efficacy but in some cases therapy that is harmful or iatrogenic. It would also be unfortunate if politically moderate or conservative clients cannot find a therapist in their community who understands their values and problems or only one who practices a politicized form of CBT that is a very poor match for their sociopolitical values…

[W]e are hopeful that enough clinicians will “resist the ideological encroachment into the field to rebuff politicized narratives, to re-assert the primacy of individual clients in all their complexity.”

Citation: Redding, R. E., Maranto, R., & Honeycutt, N. (2026). Is the victimology worldview of many young therapists ill-suited for cognitive behavior therapy? Current Opinion in Psychology, 70, 102313.

You can access the paper here for free. Note that it’s part of a special issue in Current Opinion in Psychology focusing on identity and politicization in behavior therapy.

The Nature-Nurture-Nietzsche Newsletter

Social-Justice Therapy

Read more

a year ago · 44 likes · 9 comments · Steve Stewart-Williams

Will papers like these be enough to turn the tide on wokeness in psychology? I’m not sure. But with the number of such papers growing steadily, I feel more optimistic today than I did when I had my own taste of ideological backlash five or so years ago.

Follow me on Twitter/X for more psychology, evolution, and science.

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How You Can Support the Newsletter

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I recently rejoined political scientist on the Good Fight podcast to discuss my new book, A Billion Years of Sex Differences. We had a wide-ranging conversation about what the science says about the differences between men and women, and why the topic remains so controversial.

Here are some of the many topics we covered:

• The three main types of sex differences: Mars-and-Venus differences, Mars-and-Venus-plus-exceptions, and statistical or “fuzzy” differences

• Four biases that distort the science of sex differences: the alpha bias, beta bias, gamma bias, and delta bias

• The dangers of exaggerating sex differences - and of minimizing them

• Why gay men tend to have more casual sex than straight men, while lesbians tend to have less than straight women

• Why humans are neither strictly monogamous nor highly polygynous, but somewhere in between

• The evolutionary roots of male aggression - and how civilization works to suppress it

• What drives sex differences in STEM fields

• The gender-equality paradox: why sex differences are often larger, rather than smaller, in wealthier, more egalitarian societies

• How even small differences at the mean can give rise to large differences at the extremes - what I call the tail-of-the-distribution effect

• Greater male variability in cognitive abilities: fact or fiction?

The episode is available on Spotify, Apple Podcasts, or wherever you get your podcasts. You can also find it on Yascha’s Substack or the Persuasion Substack, along with a transcript of the conversation.

Yascha Mounk

Steve Stewart-Williams on Sex Differences and Human Nature

Steve Stewart-Williams is a professor of Psychology at the University of Nottingham’s Malaysia campus and runs The Nature-Nurture-Nietzsche Newsletter. His latest book is A Billion Years of Sex Differences…

Listen now

6 days ago · 4 likes · Yascha Mounk

If you want to dig deeper into these issues, you can pick up a copy of A Billion Years of Sex Differences here.

Follow me on Twitter/X for more psychology, evolution, and science.

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On top of that, you’ll be helping support my efforts to explore important ideas and promote open, non-politicized scientific inquiry.

Thanks for your support!

Steve Stewart-Williams

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This is the latest excerpt from my book A Billion Years of Sex Differences, released on June 4. You can access the full collection here, and pick up a copy of the book here.

In this installment, I tackle a common objection to evolutionary explanations for human mate preferences: the idea that our ancestors didn’t choose their own mates, because marriages were arranged and women were often coerced into relationships. Among other things, we’ll look at:

• How arranged marriage can coexist with individual mate choice

• Why mate preferences aren’t relevant only at the start of a relationship

• How affairs and elopements may have helped shape human evolution

• Why humans may have stronger mate preferences than other animals

• How parental interference may help explain the evolution of romantic love

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A Billion Years is Out!

My new book, A Billion Years of Sex Differences, is finally on the shelves.

It's about how evolution shaped the minds of men and women - and why it matters today.

After finishing my previous book, The Ape That Understood the Universe, I swore I’d never write another. But then I was stuck at home during the pandemic, and I had an idea for a book that I couldn’t shake off. So I thought, “Fine, just one more...”

And now, five years later, it’s a real thing in the world. It feels great!

This is the last one, though...

If you’d like to read a sample or pick up a copy of A Billion Years of Sex Differences, you can do so here.

My Appearance on the Keep Talking Podcast

In other news, the first interview I recorded for A Billion Years was released today, to coincide with the release of the book. It was on ’s excellent Keep Talking podcast. These are some of the many topics we covered:

• How I fell in love with the evolutionary psychology of sex differences

• Whether A Billion Years of Sex Differences will destroy my career

• The main sex differences in our species

• Why human sex differences are relatively modest compared to those in most other mammals

• My controversial paper on sex differences in STEM

• My crazy plan to start a Substack so I wouldn’t be financially dependent on my academic job - and how, by some kind of miracle, it actually worked

• Why the science of sex differences matters

• How we should respond to sex differences as individuals and as a society: gender-role traditionalism vs. gender-role progressivism vs. gender-role individualism

The episode is available on Apple Podcasts, Spotify, or wherever you get your podcasts. You can also find it on Dan’s Keep Talking Substack and Keep Talking YouTube channel.

A New Review of A Billion Years

Last but not least, the latest review of A Billion Years of Sex Differences has just appeared in Male Psychology magazine. It’s written by Dr. John Barry, whose groundbreaking work is discussed in the book. Here’s an excerpt.

[P]eople who don’t like evolutionary psychology, or those who are wed to the idea that gender roles should be rejected on principle, are probably going to find reasons not to like this book. But for everyone else, it’s hard to find examples of where Stewart-Williams puts a foot badly wrong. This book is a mine of interesting and sensible information, engagingly written, and I thoroughly recommend it.

You can read the whole review here. And you can check out previous reviews of the book in The Times and The Guardian.

Buy A Billion Years now!

Follow Steve on Twitter/X for more psychology, evolution, and science.

How You Can Support the Newsletter

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1. Like and Restack - Click the buttons at the top or bottom of the page to boost the post’s visibility on Substack.

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Steve

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I recently sat down with the Telegraph’s science editor, Sarah Knapton, to discuss a range of topics related to my book, A Billion Years of Sex Differences.

We kicked things off with the trad wife phenomenon. Below is an excerpt on the topic from Sarah’s article. Note that the title of the article - “‘Trad wives’ are a myth as women always worked” - is somewhat misleading as women didn’t always work, at least outside the home. My point was that, among our hunter-gatherer ancestors, both sexes worked outside the home, not just men. Why does it matter what our hunter-gatherer ancestors did? Because we spent most of our evolutionary history as hunter-gatherers, and thus this way of life was the crucible in which human nature evolved.

The “trad wife” or “traditional wife” trend has spread through social media, and promotes a lifestyle in which the husband is the sole financial provider, leader and protector, while the woman is dependent and submissive…

It is supposed to be based on historical gender roles, which proponents claim have been lost in modern life.

But Dr Steve Stewart-Williams, of the University of Nottingham Malaysia, whose book ‘A Billion Years of Sex Differences’ is published on June 4, said there was little evidence to support the phenomenon.

“The idea that this is the natural arrangement for our species is, I think, very, very weak,” he explained.

“For most of our evolutionary history, women weren’t just at home with the kids; they had jobs outside the home, gathering food and the like.

“[And for] most of [our] evolutionary history, women were not isolated. They were hanging out with other adults most of the day.”

To be clear, if people want to adopt the trad wife lifestyle, all power to them. The fact that it’s not the natural arrangement for our species doesn’t mean it’s inherently bad - most ways we live today aren’t natural. My guess is that this lifestyle wouldn’t suit most women, at least not for long. But people differ, and it would no doubt suit some. And that’s what we should be thinking about when making life decisions: what would suit us, not what’s natural or unnatural.

A second topic Sarah and I discussed was sex differences in career choice. This is arguably the most controversial topic I address in A Billion Years of Sex Differences, and the one I’ve got the most grief about in the past. Here’s another excerpt:

Dr Stewart-Williams said he accepted that men and women naturally gravitate toward different types of work – with women often preferring people or language-focused roles, such as psychology, the humanities, teaching and caring professions.

Conversely, fields that are less people-oriented, such as computer science, physics, and mathematics, tend to naturally remain male-dominated.

As societies become more developed and women gain more rights and opportunities, the gender divide in careers becomes greater not less, a phenomenon known as the “gender equality paradox”.

In wealthier nations, people have the financial freedom to follow their dreams and individuality, which ends up giving natural, innate differences more room to grow, he argues…

“For a lot of sex differences, you’d expect them to be smaller in gender-equal nations, wealthier nations, nations with higher levels of human development, but instead they’re often larger,” he said.

Dr Stewart-Williams said individuals should be able to pursue whatever interests them, whether that meant women choosing STEM professions or men entering teaching and caring professions.

But he warned that because the sexes have different average interests, trying to force a strict 50-50 gender balance in every occupation is unnatural.

I’d quibble with the wording of that final line. I do think that trying to force a strict 50-50 sex ratio in every occupation would be unwise, as it would inevitably mean nudging, bribing, or cajoling some people to go into areas less aligned with their interests. But I wouldn’t say a 50-50 gender balance is unnatural - first, because none of our modern occupations are natural, and second, because the tacit assumption in this context is that “unnatural” means “bad.” It doesn’t. Plenty of unnatural things are very good, and plenty of natural things are terrible.

Note as well that I don’t deny that discrimination and socialization help shape the sex ratios of different fields. I just don’t think they’re the entire explanation. Other factors - in particular, average sex differences in career-related interests - also play a role.

You can read the whole Telegraph piece here. And you can order A Billion Years of Sex Differences here.

Follow me on Twitter/X for more psychology, evolution, and science.

Further Reading

I cover the question of sex differences in career choice in depth in A Billion Years. In addition, I’ve written several academic papers with Lewis Halsey on the topic.

The main one is this 2021 paper in the European Journal of Personality:

• Stewart-Williams, S., & Halsey, L. G. (2021). Men, women and STEM: Why the differences and what should be done? European Journal of Personality, 35, 3-39. https://doi.org/10.1177/0890207020962326 [Free version]

This was published alongside two commentaries - one favorable; one critical.

• Ceci, S. J., Kahn, S., & Williams, W. M. (2021). Stewart-Williams and Halsey argue persuasively that gender bias is just one of many causes of women’s underrepresentation in science. European Journal of Personality, 35, 40-44. https://doi.org/10.1177/0890207020976778

• El-Hout, M., Garr-Schultz, A., & Cheryan, S. (2021). Beyond biology: The importance of cultural factors in explaining gender disparities in STEM preferences. European Journal of Personality, 35, 45-50. https://doi.org/10.1177/0890207020980934

Here’s our response to the critical commentary:

• Stewart-Williams, S., & Halsey, L. G. (2022). Not biology or culture alone: Response to El-Hout et al. (2021). European Journal of Personality, 36, 991–996. https://doi.org/10.1177/08902070211022477 [Free version]

From the Archive

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To help support my work, please consider upgrading to a paid subscription. A paid subscription will get you: (1) full access to all new posts and the archive, (2) full access to my “12 Things Everyone Should Know” posts, Linkfests, and other regular features, and (3) the ability to post comments and interact with the N³ Newsletter community.

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Steve

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In Case You Missed It…

• Academia’s Leftward March

• An Evolutionary Enigma: Same-Sex Sexual Orientation is Biological But Largely Non-Genetic

• Everything You Wanted to Know About Sex Differences but Were Too PC to Ask

Welcome to the May 2026 edition of the N³ Newsletter Linkfest: a collection of links to papers and articles that grabbed my attention over the last month. On the menu today…

• Surprising news about the gender pay gap

• Psychological myths that won’t die

• The political divide separating men and women

• The media’s hate-crime blind spot

And we’ll ask: Can positive thinking extend your lifespan? Are some delinquents born while others are made? And can you tell how intelligent someone is from just a few seconds of video?

Around half the items are free to read for everyone; the rest are behind a paywall. I tend to put the spicier content behind the paywall, so if you want a taste of that, consider becoming a paid subscriber.

You can access the complete collection of Linkfests here.

Political Breakups

More than one in three Americans has lost at least one family relationship, friendship, or romance over politics. Democrats are especially prone to such “political breakups” - and people who’ve experienced them tend to see their political opponents not merely as wrong but as selfish and extreme. [Link.]

Murderous Intent

Millions of people in the US have seriously contemplated shooting someone. [Link.]

Birds Fear Women More Than Men

A curious finding from Europe: City birds are more afraid of women than men, consistently fleeing sooner when approached by a woman. This pattern was found in five out of five countries, survived a battery of controls, and left researchers scratching their heads about what on earth might be going on. [Link.]

Humorless Humans, Serious Monkeys

Here are two potentially related findings I happened to spot this month:

1. In human societies with stricter social norms and lower tolerance for deviance, people are less likely to make jokes or be skilled at humor. [Link.]

2. In monkey and ape societies with despotic leaders, adults are less likely to clown around and have fun. [Link.]

The Latest on the Gender Pay Gap

Among young Australians, women now earn more than men. The same pattern has also been observed in many US and UK cities. It’s a real and growing trend. [Link.]

The Replication Crisis

Non-replicable research gets cited more than replicable research. This is consistent with what I call Steve’s Law: Boring findings and non-PC findings are more replicable than interesting or PC ones. [Link.]

Psychological Myths and Misconceptions

People believe a lot of myths about psychology - even after they’ve taken an intro psych class. The myths in question include everything from learning styles to repressed memories to sugar-induced hyperactivity. For some reason, women believe more psychological myths than men. [Link.]

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What happens when a secular evolutionary psychologist and a Christian podcaster sit down to talk about human nature? More agreement than you might expect.

I recently joined Joseph Holmes on The Overthinkers podcast to discuss nature, nurture, and the evolution of sex differences. Among other things, we discussed:

• My new book A Billion Years of Sex Differences

• Why genetic and evolutionary explanations for human behavior make so many people uncomfortable

• Six lines of evidence that many sex differences are partly innate

• Why upbringing has less impact than we think - but it’s also not all in the genes

• The nature and nurture of criminality and addiction

• How a better understanding of human nature can help us build a better world

Despite coming at these issues from very different philosophical starting points, Joseph and I found a great deal of common ground on human nature, morality, and how best to cultivate our better angels while restraining our darker impulses.

The episode is available on Apple Podcasts, Spotify, Podbean, and wherever else you listen to podcasts.

Follow Steve on Twitter/X for more psychology, evolution, and science.

Related Reading

• You can order my book A Billion Years of Sex Differences here.

• You can read the first chapter of my previous book The Ape That Understood the Universe for free here.

From the Archive

How You Can Support the Newsletter

If you like what I’m doing with The Nature-Nurture-Nietzsche Newsletter and want to support my work, there are several ways you can do it.

1. Like and Restack - Click the buttons at the top or bottom the page to boost the post’s visibility on Substack.

2. Share - Send the post to friends or share it on social media.

Share

3. Upgrade to Paid - A paid subscription gets you:

   • Full access to all new posts and the archive

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Upgrade to paid

If you could do any of the above, it’d be much appreciated. The support of readers like you helps keep the newsletter going.

Thanks!

Steve

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This is a guest post by Turi Munthe. His book, Why We Think What We Think: The Unexpected Origins of Our Deepest Beliefs, was published on May 14 by Penguin’s Hutchinson Heinemann.

Can You Control Your Own Beliefs?

Only if you know how your beliefs control you.

A few years ago, the UK’s Guardian newspaper bravely informed its left-leaning readership that attractive people tended to lean right. The heartthrobs and dreamboats of this world - people with conventionally desirable traits like tall men and women, men with high natural upper-body strength and women with symmetrical faces - vote conservative. Specifically, attractive people are greater believers in meritocracy - the classic conservative view that you should earn what you get, and that you get what you deserve.

There’s nothing intrinsically sexy about conservatism: listening to Ronald Reagan’s speeches will not give you lustrous hair or an aquiline nose. The reason that conventionally attractive people tend, on average, to be bigger believers in meritocracy is because of something teenagers call ‘Pretty Privilege’. Beautiful people inhabit a gentler reality than us common mortals: strangers, teachers, employers and even parents all bend towards them, quietly smoothing their path. It’s no wonder they trust in a meritocracy - for them, it largely works, even if their ‘merit’ is only being pretty.

It’s a disconcerting notion. Who wants to be told their careful reading of Milton Friedman and Friedrich Hayek is just post-hoc rationalisation? That their deepest convictions are arbitrary: the fruit of happenstance rather than intellectual agency?

And yet, as I show in Why We Think What We Think: The Unexpected Origins of Our Deepest Beliefs, so many of our opinions are just that. From our faith in God to our taste in decoration, the ‘reasons’ we hold our convictions are often more accurately attributable to quirks of history, geography, climate, psychology and even genetics than to reading, deliberation and ‘reasoning’.

Wherever the climate is hot and humid - from Singapore to the DRC - people tend to be both more xenophobic and more conformist than the global average. Why? Because hot and humid climates are rich in pathogens like bacteria, fungi and parasites. The locals’ wariness of strangers comes from a heightened fear they might bring infection. And their learned conformity is a form of behavioural immunity to ensure nobody deviates from the practices they know will keep them safe from contagion.

People who score high in ‘neuroticism’ (one of our five key personality traits) are more likely to follow radical ideologies. At the 2015 general election, they were both more likely to vote for the hard-left Greens and more likely to vote for the hard-right UK Independence Party. Why? Because that existential discomfort prompts those high in neuroticism to search for radical alternatives that might fix it.

‘Moralising’ deities like God or Allah (and unlike, say, Zeus or Thor who don’t have much to moralise about given their own behaviour) almost always emerge in regions prone to drought. Why? Because drought is the great climatic killer - worse than floods or typhoons or earthquakes - and the only way to survive it as a society is to pull together. You need strict moral rules to keep the community from destroying itself - they’re less important when everyone is doing OK.

Your deepest sense of self and your relationship to the world is a by-product of the agriculture of your ancestors. There are two broad camps. Individualist cultures (like Europe) prioritise self-expression and personal autonomy over group loyalty, and collectivist ones (like Asia) prioritise shared obligations and social harmony over personal interests. If your ancestors grew up planting wheat, you’re likely the former, and if rice, then the latter. Why? Because rice cultivation takes whole communities to build the paddies, manage the irrigation systems and harvest the rice. A culture of cooperation and harmony was essential to survival. Whereas wheat can be cultivated by a single family, which afforded early Europeans the luxury of putting themselves first.

We know our beliefs are subject to the vagaries of history: 500 years ago, we’d all have believed the sun rotated around the Earth. But history influences our attitudes in much more unconscious ways too. Why are Bretons historically more liberal, less patriarchal and more egalitarian than their neighbouring Frenchmen? Because, as Asterix tells us, the Romans never truly conquered that corner of the country, and the paternalistic culture Rome spread across Europe never took root quite so deeply there.

There are countless ‘accidental’ environmental influences on our opinions - like the weather, or topography, or history - but there are also deeper ‘biological’ ones too, and they have an outsized effect on our politics.

Right-wingers, on average, have measurably more taste buds than left-wingers. It’s because people with greater ‘disgust sensitivity’ (like sensitive tongues) tend to be more conservative in all their tastes, and more judgmental of those who deviate from them.

Put a teenager in a brain scan and you can tell with 70% probability what their politics are. The amygdala, which responds to emotions like fear and threat, tends to be larger and more active in conservative teens; the prefrontal cortex, which processes ambiguous information and works to resolve cognitive conflict, is more active in liberal ones. That enlarged amygdala might be behind right-wing concerns about immigration or crime. And that overactive prefrontal cortex might explain why liberals tend to be more tolerant of difference or why so many pernickety academics lean left.

Your politics owe more to your genes than to your reading. Identical twins who share 100% of their DNA have MUCH more similar politics than fraternal twins who share only 50% of their DNA, even when they were raised apart. By comparing identical and fraternal twins’ beliefs, we know that genetics explains around 50% of the variance in our views on tax policy (or porn), for example. That means that half of the differences between people’s opinions on things like government spending (or banning Pornhub) can be traced back to their genes – inherited traits from their biological parents.

Our opinions are not predetermined: we can control our beliefs. Some cuties do vote Labour, just as some trolls vote conservative. We are, as the famous phrase goes, hardwired not to be hardwired. Humans have the most extraordinary capacity for reason. We do have intellectual agency. We can and frequently do change our minds. But we are predisposed to many of our beliefs. Acknowledging that, and understanding how the quirks of history, geography, climate, psychology and even biology unconsciously influence our worldviews is the first step towards achieving intellectual independence from ourselves.

Turi Munthe is the author of Why We Think What We Think: The Unexpected Origins of Our Deepest Beliefs, which was published 14 May with Penguin’s Hutchinson Heinemann.

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The second review of A Billion Years of Sex Differences just dropped!

This one’s by Sophie McBain in The Guardian. The Guardian tends to lean progressive, so I had wondered how the book would be received. But it’s a very thoughtful review, and a very positive one overall.

The opening paragraph summarizes the book nicely:

According to the evolutionary psychologist Steve Stewart-Williams, almost everyone gets sex wrong. Traditionalists tend to exaggerate the natural differences between men and women. Progressives tend to minimise them, and to assume that nurture and socialisation play a decisive role. He wants to promote a more nuanced, scientifically rigorous public conversation about why and how men and women differ to guide better policymaking.

McBain adds that the “book is filled with interesting, counterintuitive findings, studies you might want to discuss with a friend.”

There are some parts of the review that I’d quibble with and that I think McBain gets wrong. For example, she claims I don’t discuss our history of anti-female bias, but I do. And she suggests that it’s rather convenient to focus on innate influences rather than the structure of the workplace, when I argue we should focus on both.

But none of her criticisms are particularly unreasonable or unfair, and my overall impression is that she’s sincerely engaged with ideas that are outside her comfort zone. Who could ask for more?

You can read the whole review here. And if you’d like a copy of the book, you can order it from the Guardian Bookshop at a discount.

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This is the latest excerpt from my book A Billion Years of Sex Differences. You can access the full collection of excerpts here, and pick up a copy of the book here.

In this installment, I share one of my favorite sections of the book, which explores one of the deepest patterns in nature: greater female choosiness about sexual partners. Among other things, we’ll look at:

• Why men dominate what biologists call “mate-choice failure”

• Why women swipe right less

• Why some female animals would rather fake their own deaths than mate

• Why even female plants are choosy about their sexual partners

• Why men are less choosy in casual mating but not in long-term relationships

• Why female orgasm may be choosier than male orgasm

Women Are Choosier than Men About Their Mates… But Not Always

Aside from sexual orientation, the most fundamental sex difference in mate choice concerns overall sexual choosiness. The evolutionary rationale for this difference is straightforward. Both sexes evolve to be choosy in proportion to their level of parental investment. If females and males in a species invest equally in the young, the sexes evolve to be equally choosy. Conversely, if one sex invests more than the other, the higher-investing sex evolves to be choosier than the lower-investing sex. As we know from earlier excerpts, in most species, females invest more than males in each offspring. Ergo, females in most species are choosier about their mates.

Even a cursory glance at the living world confirms the accuracy of this claim. A common trend among animals is that males do everything within their power to impress females, only for the females to remain entirely unimpressed, nine times out of ten. A nice example concerns the greater superb bird of paradise. Males in this species perform one of the most elaborate and bizarre courtship dances known to modern science; google it if you want to feel insecure about your own dance moves. Despite the male’s strenuous efforts, however, females typically reject several dozen suitors before finally consenting to mate. The funny thing is that because females evolved to be so super-choosy about the males’ displays, we humans are probably more impressed by the superb male’s dance than is the average female of his own species. Ditto the peacock’s tail and every other nonhuman mating display.

Greater female choosiness doesn’t just explain males’ desperate attempts to wow the ladies; it explains all sorts of otherwise mysterious behaviour found across the animal world. In some frog species, females fake their own deaths to escape unwanted male attention; males, on the other hand, never fake theirs to escape female attention. In some spiders, females attempt to eat any male that tries their luck with them, thus filtering out suitors that don’t have the skills to avoid becoming dinner. And in some octopus species, females throw shells and other objects at amorous males who they don’t feel measure up. Even apparent exceptions to the choosy-female rule generally turn out not to be. We saw in a previous excerpt that female chimps and bonobos are highly promiscuous, commonly mating with every adult male in the group. Importantly, though, underneath this stereotypically male behaviour is a strong undercurrent of stereotypically female choosiness. The females’ sexual adventurousness, you see, is largely confined to the period leading up to estrous – that is, the period before they’re fertile. As soon as estrous kicks in, the females become much more socially conservative, reserving their sexual favours for the highest status males.

And we’re still only scratching the surface! Female choosiness isn’t just a behavioural phenomenon; it’s often stamped into female anatomy and physiology. Some female ducks, for instance, have corkscrew vaginas that spiral in the opposite direction to the males’ corkscrew penises, helping them to avoid fertilization by rapist males. In some species, including some rodents and sea urchins, eggs are choosy about which sperm they allow to fertilize them. And in some plants, female reproductive organs are choosy about which pollen they accept, selectively aborting ovules fertilized by suboptimal pollen. Yep, that’s right; greater female choosiness isn’t even confined to animals. It’s an extremely deep trend in nature.

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The first review of A Billion Years of Sex Differences just appeared in The Times!

I probably wouldn’t have chosen the title - “Why men are promiscuous and women are choosy” - but I’m very happy with the review itself.

Below is a brief excerpt. You can read the whole thing here. And if you’d like a copy of the book, you can order it from the Times Bookshop.

Within every nation, men watch more pornography, use more prostitutes, are more interested in one night stands, masturbate more, cry less, are more likely to murder and die in car crashes than women…

When men have absolute power, they get a harem. When women have power — well, let’s just say that Queen Victoria wasn’t noted for her tendency to fill the court with nubile young men.

And if men can’t get a harem? “Men corner the market on what evolutionary biologists call mate-choice failure, with documented cases involving everything from lampposts to trees to vacuum cleaners.”

Of course, it’s not so much the existence of these differences that is so controversial among his academic colleagues. Rather it is the assertion that these differences are in some way innate. Are women really less likely to fornicate with trees? Or has the patriarchy simply repressed their latent arborophilia?

Stewart-Williams’s position is the former…

Where Stewart-Williams is most persuasive is in laying out the areas of uncertainty, acknowledging the importance of nurture, but arguing forcefully that there is a core of irreducible difference that is so obviously down to nature that — well — it takes a very clever social scientist to claim otherwise.

“No one would argue that female and male raccoons act differently because they’re rewarded for behaviour consistent with arbitrary raccoon gender roles,” he writes. So why do we do that with humans? “Why would natural selection wipe the slate clean of these sex differences in our species alone, only for us to then reinvent the same set of sex differences in every society on record?”

You can order a copy of A Billion Years of Sex Differences from the Times Bookshop here.

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Men have more dreams with competition-related themes than women do; women have more dreams with social themes - a pattern consistent with broader sex differences in human motivations. Beyond these domains, however, men’s and women’s dreams are largely similar.

The graph comes from a recent paper by Zachary Grant and colleagues. Here’s an excerpt:

We explore whether sex differences in evolved behavioral and cognitive strategies shaped by distinct evolutionary pressures are expressed in dream content. We hypothesized that biological sex influences dream content; specifically, that females would report more dreams featuring social and emotional themes, while males would more frequently report dreams involving competition-related content (e.g., risk, reward, and threat), reflecting sex-differentiated ancestral challenges. With a sample of 298 participants logging 4641 dreams, we evaluated dream content across six thematic domains: Emotional Valence, Positive Emotional Content, Negative Emotional Content, Social Content, Competition-based Content, and Resource Acquisition-based Content. Using a mixed-effects model, we discovered that males were significantly more likely to report dreams involving competitive content, while females showed a higher propensity for social dream content. No other themes, including the domains of emotional content, yielded significant results. While these patterns are consistent with possible adaptive functions of dreaming, they may also reflect hormonal influences, socio-cultural factors, personality differences, or other non-evolutionary contributors. Our results extend existing literature on sex differences in dream content using text-based scoring methods, offering a nuanced perspective on how dreams may relate to both biological and social influences.

• You can access the paper here for free.

• For more on the evolution of sex differences, you can preorder my forthcoming book, A Billion Years of Sex Differences, here. Note that paid subscribers to The Nature-Nurture-Nietzsche Newsletter can read exclusive excerpts from the book before the official publication date.

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Universities have leaned left politically since at least the 1960s. In itself, that’s not a problem. Different professions attract different kinds of people. Artists lean liberal. Soldiers lean conservative. Why should academics be any exception?

But there’s a difference between a lean and a monopoly - and American academia is rapidly approaching the latter. According to a recent paper by Nathan Honeycutt, 74% of US faculty identify as liberal, 15% as moderate, and only 11% as conservative. Remarkably, more faculty identify as “far left” or “very liberal” than with any position right of center.

This matters because intellectual progress depends on disagreement. When dissenting voices vanish, institutions don’t become wiser; they become more vulnerable to groupthink, motivated reasoning, and the comforting illusion that everyone sensible already agrees. If universities lose the capacity to challenge their own assumptions, their claim to be society’s truth-seeking institutions starts to look increasingly shaky.

In this post, I’ll outline five key findings about the political makeup and trajectory of academia, captured in five fascinating graphs.

1. Even the Center is Vanishing

The first graph shows the increasing dominance of the left in academia from the late 1960s to the early 2020s. As you can see, liberals and leftists have always outnumbered the rest, but the skew has grown increasingly strong over time. And not only have conservatives become vanishingly rare, so have centrists. That’s how complete the left’s dominance is: Even moderates are now a fringe group in academia.

2. Representation Matters - But Only the “Right” Representation

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Same-sex sexual orientation is a genuine evolutionary mystery. Traits that reduce reproduction are not supposed to persist - yet homosexuality does.

How?

In this excerpt from my book A Billion Years of Sex Differences, I explore the latest scientific answers to this question. Along the way, I dismantle some persistent myths, explain why same-sex orientation is neither a product of socialization nor an evolved adaptation, and argue that the best evidence points to a surprising conclusion: that sexual orientation is biological but largely non-genetic.

You can access the full collection of excerpts here, and pick up a copy of the book here.

Nature’s Rainbow

Let’s wrap up the discussion of sex differences in sexual psychology by exploring the question I’m most often asked when I give talks on the topic: Why are some people exclusively attracted to members of their own sex?

Heterosexuality is no mystery in evolutionary terms. Its primary function is clearly about making new life, and secondary functions – such as galvanizing the bond between potential parents – are just as clearly linked to the primary function. As soon as we put on our Darwinian goggles, however, homosexuality starts to seem mysterious. The mystery is not that individuals sometimes engage in sexual activity with members of the same sex; the occasional same-sex dalliance is unlikely to have much impact on the number of children one has in one’s lifetime. The mystery is that a non-trivial number of people never want to have sex with members of the other sex. Individuals with such a profile might occasionally have children, especially in societies with strong social pressure to marry and have a family. More than likely, though, they’ll have fewer children than people with a heterosexual (or at least a bisexual) orientation. This is especially true of men, because of men’s higher maximum offspring number.

How, then, does homosexuality persist? To the extent that it’s genetic, why hasn’t selection removed the genes contributing to its development from the gene pool? To the extent that it has non-genetic causes, why hasn’t selection made the development of heterosexuality more robust to perturbations?

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In Case You Missed It…

• The Science of Controversial Science

• 12 Things Everyone Should Know About Wokeness

• IQ and Mental Health, Bias Against Men in the Courtroom, and Declining Trust in Institutions

We’d all like to believe that the criminal justice system is rational: that punishments are meted out fairly, consistently, and in ways that promote the common good. And contrary to the cynics, they often are. In certain respects, however, the system falls short of this ideal. People’s biases and instinctive taste for vengeance sometimes intrude on legal decision-making, such that offenders are punished in ways that have little to do with fairness or social utility. While racial biases in criminal justice are widely recognized, other biases - including those based on sex - receive far less attention. In this essay, I explore how these biases shape punishment, and what this reveals about the gap between justice as it is and justice as it ought to be.

The Goldilocks Approach to Punishment

When it comes to theories of punishment, one stands head and shoulders above the rest: optimal punishment theory. Most famously associated with the economist Gary Becker, optimal punishment theory treats criminal justice as a matter of balancing costs and benefits. The central idea is that punishments should be set at a level that minimizes both the costs of crime and the costs of punishing it.

This deceptively simple premise yields various concrete proposals about how society ought to punish different crimes and different criminals. One is that crimes that are harder to solve should attract harsher penalties, so the average expected cost of offending remains high despite the lower probability of getting caught. A second is that criminals at greater risk of reoffending should be punished more severely, both to deter them effectively and to incapacitate them for longer. And a third is that punishment should not be shaped by factors that are irrelevant to the goal of minimizing the combined costs of crime and punishment.

In short, punishment should be neither too harsh nor too lenient, but “just right” for minimizing social harm.

Does the System Measure Up?

All of this sounds eminently reasonable - but to what extent does reality approach the ideal? Many studies have addressed this question over the years, but one particularly illuminating contribution is a paper by Edward Glaeser and Bruce Sacerdote titled “Sentencing in Homicide Cases and the Role of Vengeance.” The paper tests some of the central predictions of optimal punishment theory by examining sentencing patterns in US homicide cases.

In some ways, the news is good. Glaeser and Sacerdote report, for example, that offenders tend to be punished more severely when the risk of getting caught is low, consistent with the idea that harsher penalties are needed to deter potential offenders in those circumstances. Thus, arson-related homicides receive longer sentences than homicides during robberies, which in turn receive longer sentences than homicides during drunken brawls.

Also consistent with optimal punishment theory, offenders at higher risk of reoffending tend to be punished more severely. People who kill during a robbery, for instance, receive longer sentences than those who kill during a fight or lovers’ quarrel.

So far, so good. In these respects, the system behaves roughly as optimal punishment theory would predict and recommend.

But then things start going off the rails.

Bias in the Machine

One of the central premises of optimal punishment theory is that factors unrelated to crime risk should play no role in determining punishment. But Glaeser and Sacerdote found compelling evidence that they do.

The researchers looked at two broad categories of influence: demographic characteristics of the offender and demographic characteristics of the victim.

Let’s begin with the offender. A large body of research suggests that various demographic traits influence sentence length even after controlling for potential confounds such as crime severity and criminal history. Perhaps the least surprising example is that Black offenders tend to receive longer sentences than White offenders for the same crime. More surprising to many is that men tend to receive longer sentences than women. Indeed, women from every ethnic group - even the least favored - tend to receive shorter sentences than even the whitest of White men.

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People aren’t always great at figuring out what’s going on in others’ heads. Nowhere is this truer than in the realm of sex and love. Here are three findings from recent research by Paola Baca and colleagues, cataloguing common mindreading errors in the sexual sphere.

1. Both sexes overestimate the average person’s desired number of sexual partners. Men overestimate the average man’s desired number more than women do. Men and women overestimate the average woman’s desired number to the same degree.

   

2. Both sexes overestimate how willing men and women would be to have sex with someone they’ve known for a given length of time: an hour, an evening, a day, a week, an month, etc. They especially overestimate men’s willingness.

   

3. Both sexes overestimate how comfortable the average man is with sex without love. Men slightly overestimate how comfortable the average woman is; women get it about right.

   

Notice that, in all these cases, men and women do in fact differ on the relevant traits, but that the differences aren’t as large as people think. This has an interesting implication. It suggests that the main lesson of research on sex differences isn’t that the sexes differ when people thought they were the same, but rather that they don’t differ as much as people tend to assume!

• You can access the published paper here or request a free copy from the authors here.

• For more on this topic, you can preorder my forthcoming book, A Billion Years of Sex Differences, here. Note that paid subscribers to The Nature-Nurture-Nietzsche Newsletter can read exclusive excerpts from the book before the official publication date.

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Why are men more interested than women in casual sex and sexual variety?

The standard answer is simple: Men can father more children, so they evolved to want more partners.

It’s a nice, tidy story - and it’s partly true.

But it also fails to explain a lot of what we actually see in the world. In many species, females are far more promiscuous than the standard story predicts. And in our own species, sex differences in sexual psychology, though real, are smaller than you might expect.

In this excerpt from my book A Billion Years of Sex Differences, I lay out a new way of thinking about the evolution of sex differences in sexual psychology - one that goes beyond the usual focus on maximum offspring number and brings a wider range of evolutionary forces into view.

You can access the full collection of excerpts here, and pick up a copy of the book here.

The Evolution of Sex Differences in Sexual Psychology: It’s Not (Just) What You Think

We saw in the last excerpt that sex differences in sexual psychology aren’t just a product of culture; there’s also an innate contribution. Importantly, though, to say that there’s an innate contribution is to say nothing about how it came about. Why did natural selection ‘decide’ to give men and women somewhat different, somewhat incompatible desires? If a god were behind it, we might suspect that he was playing a cruel joke on us or trying to make the soap opera of human life more entertaining for himself. With natural selection as the architect, however, no such explanation is available. Somehow, male-typical sexual leanings must have been adaptive for our male ancestors, whereas female-typical sexual leanings must have been adaptive for our female ones. The only real question is why.

Now, you might think you know the answer already. I touched on it in Chapter 4, and in any case, the basics are quite well understood these days. But not so fast. As with sexual selection, the evolutionary explanation for sex differences in sexual inclinations is long overdue for an overhaul. The aim of this section is to sketch out a new and improved version of the explanation. We’ll start with the standard story, then gradually thicken the plot.

The standard story goes like this. As a result of sex differences in reproductive physiology, men can potentially have many more offspring than women. A man who has, say, five sexual partners in a year could end up with five new offspring; in contrast, a woman who has five sexual partners in a year would probably end up with no more offspring than she would if she’d just had one.

This created very different selection pressures for our male vs our female ancestors. Men who sought multiple partners typically had more offspring than men with less wide-ranging interests, and the genes underpinning that tendency became increasingly common in the human gene pool. Men evolved a higher sex drive, a greater hunger for casual sex, a stronger desire for sexual variety, and a capacity to be quickly aroused by sexual stimuli (which for most of our evolution meant flesh-and-blood women rather than porn).

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Long before they can walk, talk, or tie their shoelaces, infants have a rudimentary sense of beauty. By four months of age, babies look longer at patterns that adults judge to be beautiful. This suggests that, like our love of faces, the aesthetic sense may be built into the human mind from the start.

The graph comes from a recent paper by Hélène Mottier and colleagues. Here’s the abstract:

The present study investigated the emergence of a visual preference for beautiful kinetic dot displays during development. The displays were previously judged for relative beauty by an independent group of adults. Preferential looking was measured with an eye tracker in 4- to 24-month-old infants and adults. Analysis of the overall preferential looking response over the 5 s of stimulus display indicated that adults’ judgement predicted preferential looking at all ages tested. Analysis of the time course of this attentional response indicated two different mechanisms: (i) a fast-orienting response towards motion patterns that were not judged as beautiful by adults, and (ii) a slower but longer-duration response towards motion patterns that were judged as beautiful by adults. The contribution of these two mechanisms to the overall preferential looking response changed with age in a consistent manner. Because the beauty ratings of adults were associated with a later but longer-duration visual attention response in infants, and most preferred patterns differed in many aspects from non-preferred patterns, we propose that a sense of beauty, defined in adults as a pleasurable mental state leading to sustained visual attention, may influence behaviour by four months of age when looking at kinetic dot displays.

You can access the paper here for free.

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How You Can Support the Newsletter

This post was free to read for all. If you like what I’m doing with The Nature-Nurture-Nietzsche Newsletter, and want to support my work, there are several ways you can do it.

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Related Reading From the Archive

In Case You Missed It…

• Top 10 Most Replicable Findings from Behavior Genetics, Part 2: Findings #6-10

• Keeping It Casual, Part 2: The Nature and Nurture of Sex Differences in Casual Sex

• People Prone to Corporate Bullshit Tend to Make Worse Leaders

Welcome to the April 2026 edition of the N³ Newsletter Linkfest: a collection of links to papers and articles that grabbed my attention over the last month. On the menu today…

• An innate sense of kindness in humans and dogs

• Why greater gender equality means fewer babies

• Three new findings on personality, three new findings on sex differences, and three new findings on gender issues

• The lengths females go to to avoid unwanted male attention

• The downside of reclaiming slurs

• And we’ll ask: Which is more common, misogyny or misandry? Does gender reassignment help or harm the mental health of youth with gender dysphoria? And does DEI foster inclusion and mutual understanding or division and hostility?

The first half of the Linkfest is free to read for everyone; the rest is for paid subscribers. I tend to put my spicier content behind a paywall, so if you want a taste of that, consider becoming a paid subscriber.

You can read about the benefits of a paid subscription here, and you can access the complete collection of Linkfests here.

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But First, Some News…

I’ll be appearing at the How the Light Gets In festival in Hay-on-Wye this May 22-25, doing a debate about the merits and demerits of spirituality, a podcast with , and an event for my forthcoming book A Billion Years of Sex Differences.

Wanna come? You should come; it’ll be fun!

Explore tickets

Echolocation in Humans

Some blind people don’t just learn to live without vision; they replace it with something arguably just as impressive: echolocation. Specifically, they make click sounds with their mouths, then use the returning echoes to detect objects and navigate through the world. In a clever EEG study, blind echolocators outperformed sighted participants at locating objects in the dark, progressively refining their spatial judgments by integrating echoes across multiple clicks. [Link.]

Born to Give

Toddlers, it turns out, are tiny altruists: They’re happier giving treats away than receiving them. Not only that, but they’re happier when they personally give the treats than when someone else does, and happier when they give them spontaneously than because they were told to. This is suggestive evidence that human altruism is driven by the inbuilt emotional rewards of lending a helping hand. [Link.]

Dogs Help, Cats Watch

Dogs are about as helpful as toddlers, but cats look out for number one. In a fascinating recent experiment, a human parent pretended to be looking for a lost object. Around three-quarters of toddlers and dogs tried to help. Most cats, in contrast, sat back unless there was something in it for them. Helpfulness, it seems, comes more naturally to some species than others. [Link.]

More Equality, Fewer Babies

Fact: Across countries, greater gender equality is associated with lower fertility. Theory: With greater freedom and material wealth, women become less dependent on men, and thus less likely to form pair bonds. Combine this with reliable contraception, and the fertility rate comes crashing down. [Link.]

The Missing 5’11” Men

Something strange is happening with self-reported height among men: There aren’t enough 5’11” men, and there are too many 6’0” men. Hmmm... [Link.]

The Paradox of Upward Mobility

We tend to assume that people who are born poor and get rich will be more sympathetic to the plight of the poor than those who are born rich and stay rich. But it’s the other way around: Those who start out poor are less sympathetic. [Link.]

A Billion Years of Plate Tectonics

This incredible animation compresses a billion years of plate tectonics into just 40 seconds. We tend to think of land masses as stable - but they’re in constant motion. They just move a lot more slowly than us. [Link.]

Three New Findings on Personality

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