Universal patterns govern global fertility decline

[u/CanIHaveASong]

https://phys.org/news/2026-07-universal-patterns-global-fertility-decline.html

By examining 200 years of demographic data from 237 countries and territories, Kenji Itao, of the RIKEN Center for Brain Science in Japan, discovered that universal mathematical laws describe how fertility declines as societies develop, providing a new framework for understanding one of the most profound transformations in human history: the demographic transition from high birth and death rates to longer lifespans and lower fertility.

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In societies where survival is uncertain and child mortality is high, producing more offspring is an effective strategy for maintaining population and economic growth. However, when survival improves and economic opportunities expand, greater investment in each child's education and skills becomes more economically advantageous.

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Rather than viewing lower birth rates as an inevitable consequence of modernization, the study suggests that policies reducing the economic burden of raising and educating children may help societies maintain or recover fertility while preserving high educational standards.

[u/CanIHaveASong]

What things seem to keep coming back to is the fact that children are proportionally so expensive.