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For most of human history wealth was positively correlated with fertility and especially with next generation fertility. The trend has changed in the more recen

• somenameforme 1y ago
  But it is! To take a silly but noncontroversial example - if, for just a single fertility generation (which is driven by the female fertility window for humans - about 20 years) anybody over 5'3" stopped having children, all humans would become quite short! Of course there's some asterisks there like malnutrition may mean somebody's genetically 'normal' height is greater than their expressed height, but the broad point remains true - in a single generation there would be a dramatic transformation in humanity. This has also been observed in nature. For instance most people view the variation in Darwin's finches as something gradually happening over eons, but further studies on them showed a rapid shift in beak morphology following a single severe drought. [1] It's the same stuff - suddenly one beak became more likely to reproduce (or not), which drove a very rapid population level change. [1] - https://www.sciencedaily.com/releases/2016/04/160421145759.htm https://www.sciencedaily.com/releases/2016/04/160421145759.h...
• trallnag 1y ago
  Bottlenecks of just a few generations should have a huge impact in the longterm, no?