Some topics covered:
Discussing a 2025 study indicating that men have grown twice as much as women (both height and weight) over past century; CNN covered this finding here
Across countries, wealth is strongly linked to lower fertility. Yet within wealthy countries like the U.S., people often claim they are not having kids because they lack money. The narratives conflict, and the contradiction is revealing
I notice the same competing explanations for loneliness. People in poorer societies sometimes describe American loneliness as a byproduct of wealth and autonomy. Americans, though, often describe loneliness as the result of economic pressure
Discussing Robert Trivers’s parental investment theory. The sex that invests more in offspring tends to be more selective with regard to mates, because the costs of a bad choice are higher
In hunter-gatherer societies, raising a child from pregnancy to independence (roughly age 15-18 years old) requires roughly 10 to 13 million calories; about 20,000 Big Macs
The naturalistic fallacy and the moralistic fallacy
For personality traits, even when men and women look similar on a global score like extroversion, they can split on facets like assertiveness versus enthusiasm
The biggest average sex differences show up in agreeableness and emotional stability
Connecting personality to politics
A small but vivid social observation from Robin Dunbar: women tend to face each other directly when talking, but men often stand at an angle, as if direct staring still carries a hint of threat
Men are twice as likely as women to have participated in a polyamorous relationship and three times as likely to want one. Men are also far more supportive than women of non-monogamy, open relationships, friends with benefits, throuples, and swinging
Among men, handgrip strength is inversely correlated with depression and positively correlated with extraversion. Handgrip strength is also correlated with self-assessed happiness, health, confidence, and overall number of sexual partners.
Answering a reader’s question about hypergamy, the practice of marrying or forming relationships with a partner of higher socioeconomic status, sometimes referred to as “marrying up”
Discussing “willingness to protect” as an attractive trait; more in my essay on this here
Join me for my next live video in the app.
