An article in The Times today reports that information from the National Audit Office (NAO) of the United Kingdom to the effect that “Family sizes shrink to their lowest level”, with the fertility rate dropping to 1.9 children per woman. Around 20% of women do not have any children, a proportion that is, it seems, historically anomalous.

An ONS statistician is quoted with a precise summary:

"Women born in 1971 who completed their bearing in 2016 had an average 1.9 children per woman, fewer than their mothers' generation, born 1944, who had 2.21 children, and the lowest level on record."

Some will doubtless interpret this as showing that rich people have other interests than fulfilling biological drives, but there are other possible explanations. – In a complex, competitive society the cost of maintaining a satisfactory position from which an individual can securely reproduce leaves less over for investment in the offspring, a pressure that encourages lower fertility to maintain high levels of resource concentration per child. On this view, in spite of appearances, and careless chatter about the demographic transition, people are still maximising their reproduction, but the conditions are such that this means smaller family sizes. Another way of approaching this is to say that as general societal complexity moves further from thermodynamic equilibrium, the human species is becoming further K-shifted in its reproductive strategies.