I would argue humans are devolving. The most intelligent barely bread, the stupid breed like rabbits.
The 20th century was a time of tremendous stress on the human genome.
In Europe, tens of millions of the finest were killed. We are concerned about the deaths of one or two of our troops in Afghanistan. On several different occasions in WW II battles tens of thousands were killed on one day.
As time progressed, the bottom of the various national barrels were dredged up to draft troops go fight in WW I. The death toll among German and Russians on the eastern front in WW II is incomprehensible.
The USA was largely exempt from this loss of genes. While there were very substantial losses, proportionally compared to Europe, they were very small.
In Europe today, there is a strong political desire to permit immigration. There can be two results. Hybridization or Replacement. In standard survival of the fittist terms, replacement is the method whereby there is change within a species that can result over time in a new species altogether. The outcome in Europe is presently unclear. However, the remaining gene pool apparently lacks the wherwithal to prevent it’s own elimination.