Update

This is an Update that is such a shameful omission on my part that it needs to be a separate post.  Eugen Fischer, the Nazi scientist and colleague of the Darwinist Karl Pearson in the 1920s was, two decades earlier, a scientific member of the German genocidal policy in Africa in 1906, in what is, today Namibia.  Scientific work in which he, personally, did experiments on Africans held in death camps and from which he shipped scientific samples of those killed back to European universities, many of those looted body parts from his victims, the focus of political and social pressure on the University science departments for them to send the back to the place their owners were murdered.  

I would count it as a virtual certainty that Karl Pearson would have known about that as he wrote the 1925 paper, using the tool of racial classification he got from his scientific colleague, Fischer, to get results that the Nazi Fischer would cite in the book that I have been discussing.  I will look to see if Pearson ever mentioned it in his papers, as I can find online or whatever evidence there might be of his awareness of Fischer's pre-Nazi genocidal activity for which he never paid a single bit of professional cost. 

Eugen Fischer cites his own findings from the African genocide to assert, within science, that intermarriage of different racial groups led to a dangerous degeneration of the "superior" population.  My scare quotes, not science's.