The combined effect of sex-selection and low fertility

Despite the headline, not much new in this report from the BBC, 'Remarkable' decline in fertility rates by James Gallagher. We've seen this developing for thirty years. However, Gallagher does connect two pieces of knowledge, both of which I knew, but which I have not particularly considered in tandem.

China has seen huge population growth since 1950, going from around half a billion inhabitants to 1.4 billion.

But it too is facing the challenge of fertility rates, which stood at only 1.5 in 2017, and has recently moved away from its famous one child policy.

The reason developed countries need a fertility rate of 2.1 is because not all children survive to adulthood and babies are ever so slightly more likely to be male than female.

But in China, the report shows for every 100 girls born there were 117 boys which "imply very substantial sex-selective abortion and even the possibility of female infanticide".

There has long been concern in economic circles about the risk that China might get old before it got rich. All the trend lines support the concern. China is greying already. Its population continues to expand due to demographic momentum but its fertility rate has long been below replacement. At some point there will be something of a cliff which will be very consequential, especially depending on what has happened in terms of increased political freedom and in terms of the shift into services.

I have also known that China, like India, has a marked sex-selective ratio favoring males. But, for whatever reason, I have never particularly considered the distorted sex-selective ratios in combination with the dramatically low fertility rate. I have not read any considerations about the probable tensions and effects arising when a society with a disproportionately male population encounters a demographic collapse from low fertility. I have been thinking about the probable tensions at an economic and political level but the combination effect of sex-selection and low fertility is kind of alarming.