New TechnologiesPopulation Crash Coming? Birth Rates Too Low to Prevent Extinction, Scientists Say Posted on May 3, 2025 by Administrator A new study of ancient and modern societies shows that human populations need at least 2.7 children per woman – a much higher fertility rate than previously believed – to reliably avoid long-term extinction. While a fertility rate of 2.1 children per woman is often considered the replacement level needed to sustain a population, this figure doesn’t account for random differences in how many children people have – as well as mortality rates, sex ratios, and the probability that some adults never have children. In small populations, these chance variations can wipe out entire family lineages.
