A family of four smiling and sitting in a red convertible car parked outside a house with green lawn.

Photo by H Armstrong Roberts/ClassicStock


In more prosperous societies, are men and women more similar?

Photo by H Armstrong Roberts/ClassicStock

by Kåre Hedebrant & Agneta Herlitz + BIO





How much the sexes differ psychologically depends on how fair and wealthy a country is. But not in the way you’d think

When it comes to gender equality, no society is perfect, but some are widely understood to have come further than others. These societies do a better job of offering equal opportunities, rights and responsibilities, and minimising structural power differences between men and women. One might expect that men and women in these societies would also become more similar to each other in terms of personality and other psychological qualities. Research has previously found differences in men’s and women’s average levels of characteristics such as self-esteem and sensation-seeking (both typically higher in men), emotional perceptiveness (higher in women), and some cognitive dimensions (though not overall cognitive ability). Do these differences become less pronounced when women and men are more equally empowered?

Surprisingly, researchers have sometimes found the opposite to be true: that improved living conditions, including greater gender equality, are associated with larger psychological differences between men and women. This phenomenon is often referred to as the ‘gender-equality paradox’.

For instance, a 2018 study comparing 22 countries found that higher scores on the Gender Gap Index (GGI), indicating higher gender equality within a country, were strongly associated with larger sex differences in commonly measured personality traits. Women typically rated higher than men on each of the so-called Big Five traits – openness, conscientiousness, extraversion, agreeableness, and neuroticism. But these differences were all larger where GGI scores were higher. (To be clear, in these examples and those that follow, we are talking about differences in group averages; there is a great deal of overlap between men and women on all these traits.)

The personality study is just one of several studies showing that some psychological sex differences are larger in countries with higher gender equality, or in countries with better living conditions more broadly – countries that are wealthier and more highly educated, for example.

There is, of course, much debate surrounding the causes of psychological differences between sexes, especially regarding the relative contributions of biological and environmental factors. The gender-equality paradox is sometimes brought to bear on these issues. Some theories of psychological sex differences propose that they stem from men and women being socialised into distinct gender roles. This process is believed to start in early childhood, with societal expectations constantly pushing individuals to behave in specific ways depending on whether they are male or female. But some researchers argue that the gender-equality paradox undermines social-role theories of sex differences. If such theories were correct, the argument goes, we would not see larger sex differences in more gender-equal countries, since that is presumably where gender roles are weakest.

Better living conditions are associated with men and women becoming more similar in some ways, but more different in others

The gender-equality paradox does not hold true for all psychological differences, however. For example, differences between women and men related to sexuality, such as their attitudes toward casual sex, have been found to decrease with higher gender equality. It seems, then, that better living conditions are associated with men and women becoming more similar in some ways, but more different in others.

What patterns emerge if we look at the research in a more systematic way? Knowing this might help us critically examine the claims made in debates on psychological sex differences and their causes. It could also hint at how gender dynamics are likely to change as societies develop.

To this end, we reviewed and analysed dozens of previous studies on the relationship between psychological sex differences and indicators of gender equality, education and economic development (eg, national GDP per capita), as well as several other measures of living conditions. Our overview touches on sex differences in most major areas of psychology, including personality, cognition, emotion, sexuality and mental health.

Looking at the big picture, we found that most psychological sex differences are not significantly related to living conditions across countries. However, it was more common for a sex difference to be larger, rather than smaller, in countries with better living conditions. This arguably supports the idea of the gender-equality paradox. Moreover, though results were mixed when considered as a whole, they were often more systematic within specific psychological areas.

Sexuality is one of the areas where the pattern is most consistent. Typically, compared with women, men display less selectivity and greater willingness to engage in sexual behaviours of various forms, whether through extramarital sex or pornography use. These differences could have an evolutionary basis: parental-investment theory notes that, for human (and protohuman) males, sexual encounters never carried the same risk of an inescapable nine-month commitment that they do for females. This may have led to evolution favouring greater sexual selectivity in females.

Nonetheless, differences between men’s and women’s sexuality were consistently found to be smaller in countries with better living conditions. This is likely explained by environmental factors that mitigate any underlying difference – factors such as an increased availability of contraceptives and more permissive cultural norms surrounding sex.

In the area of cognitive abilities, sex differences are sometimes larger, sometimes smaller in countries with better living conditions. On close inspection, though, the results follow a pattern. In domains where women perform better than men, the performance gaps increase further as living conditions improve. Thus, in countries with higher levels of development, women show greater advantages in verbal abilities (eg, reading comprehension) and episodic memory (memory for experienced events). By contrast, in domains where males perform better, sex differences typically get smaller with improved living conditions. This was the case for mathematical abilities and semantic memory (memory for facts).

If the personalities of men and women drift further apart as development unfolds, the same might happen to their politics

Why do we see this pattern? It is well established that improved living conditions are associated with increased cognitive performance. This is illustrated by the fascinating finding of a global increase in IQ scores during the 20th century and beyond, a result known as the Flynn Effect. Women’s cognitive performance appears to be disproportionately helped by this effect. This may be because women start from a more disadvantaged place, reaching a more equal footing as societies develop. In other words, women may see improvements due to balancing effects, such as more gender-equal education, in addition to other benefits from development in their society. An apparent exception to this pattern is spatial abilities (eg, the sort of reasoning involved in assembling a Lego set) where there is a male advantage showing no systematic association with living conditions.

Finally, men and women seem to adopt increasingly different personality traits – including the Big Five traits mentioned earlier – as societies develop, consistent with the gender-equality paradox. This could be a result of some importance, since personality influences our choices and behaviours in a wide variety of contexts. One area that might be affected is politics, as there is evidence that Big Five traits influence political convictions and voting behaviour. If the personalities of men and women drift further apart as development unfolds in a society, the same might happen to their politics, raising concerns of a political landscape increasingly characterised by polarisation along gender lines.

What could explain the increases in personality differences? Some researchers favour a ‘resource hypothesis’, based on the idea that there are intrinsic tendencies for men and women to be psychologically different (presumably for evolutionary reasons). However, in less economically developed societies, people’s choices are largely dominated by goals tied to basic necessities. Whether male or female, people must devote a lot of energy to subsisting, and these gender-neutral goals might drown out gender-specific preferences. It is only when societies achieve greater prosperity that such gender-specific preferences can be expressed more freely.

Here is a hypothetical example. In poorer countries, people are presumably more desperate to find better-paying jobs. We can imagine that a certain level of social forwardness is needed to compete for these jobs. This might push people toward a more extraverted behavioural pattern, characterised by talkativeness and outgoingness, as opposed to an introverted one, which is more reflective and reserved. But if conditions improve, the pressure to be extraverted might be reduced. If more men than women tend to have an inherent preference for introverted behaviour, then men will drift in that direction more than women will, increasing this sex difference.

Although that is just a hypothetical, this sort of account could help explain why some sex differences grow as living conditions improve. Moreover, the resource hypothesis implies that improved economic circumstances, not gender equality, ought to be the most important factor in promoting larger sex differences. And indeed, we found that economic metrics were the most sensitive predictors of the magnitude of sex differences. So, our findings support the resource hypothesis to some degree.

Women entering stereotypically ‘female’ professional roles may internalise the ‘female’ values of these roles

However, there is still an argument to be made for social-role explanations. The social-role theory proposed by Alice Eagly and Wendy Wood argues that psychological differences between men and women originally stem from differences in physical attributes. They specifically point to women’s capacity for bearing and nursing children, and men’s greater size and strength. Because of these characteristics, men and women have historically tended to take on different sorts of tasks, resulting in a gendered division of labour. This, in turn, caused various expectations to form about the proper social roles of men and women.

Gains in economic prosperity have coincided with more women entering the job market, and they have disproportionately done so in fields such as healthcare, education and social services, while jobs requiring physical strength and technical skills have remained dominated by men. Following social-role considerations, we can speculate that women entering stereotypically ‘female’ professional roles may internalise the ‘female’ values of these roles. This could strengthen or maintain some psychological sex differences in countries with better living conditions.

For instance, nurses – the largest professional group among US women – may absorb the care-oriented values, such as empathy and compassion, that are emphasised in their work. High female numbers in fields like nursing could thereby contribute to women being more likely than men to espouse such values. This might end up fuelling expectations that push women to be more care-oriented than men. Such effects could also become self-perpetuating, with men’s and women’s occupational choices both driving gender-role expectations and being driven by them.

The current state of research may not allow us to conclusively favour either the resource hypothesis or the social-role hypothesis – nor is it clear that they are mutually exclusive. But even more important than the explanation we choose could be the overall trends we observe.

Some psychological sex differences seem to decrease as living conditions improve, more seem to increase, and most remain unaffected. This result offers little support for the idea that sex differences will decrease – let alone vanish – as societies develop economically and achieve greater gender equality. Rather, we can probably expect these differences to remain largely intact. Looking at the Scandinavian countries, for example, there is little question that they are more gender-equal and wealthier than the majority of countries in the world. Yet on many dimensions, this has not translated to these countries’ men and women being more psychologically similar. We might draw various implications from this. It suggests, for example, that improved living conditions alone are unlikely to result in men and women choosing to enter the same professions at equal rates, even if these professions become less rigidly segregated.

The study of psychological sex differences is highly complex, so we must draw conclusions with great nuance and care. What the research tells us is that any simple story about sex differences and developing societies will not get us very far. The idea that psychological differences between men and women are permanently fixed in place does not fit with the data. But neither does the assumption that these differences will fade away as opportunity grows.





25 June 2024