XPost: alt.fan.heinlein   
   From: ldo@nz.invalid   
      
   On Thu, 12 Feb 2026 03:07:57 +0000, danny burstein wrote:   
      
   > Heinlein's character is initially disapproving, but then works out   
   > the actual math (at least as he figures it) and regards to   
   > inbreeding of genetic issues, determines it's pretty small, and has   
   > them go for it.   
      
   The Egyptian Royals had brother marrying sister, because royal blood   
   was considered too precious to dilute with that from commoners.   
      
   At least, this was true of the Ptolemaic Dynasty (the one with all the   
   Cleopatras). What would that kind of thing do to the gene pool after a   
   few generations straight?   
      
   Also, I was contemplating the contrast between the Westermarck Effect   
   and Genetic Sexual Attraction; the one says that individuals brought   
   up together, whether related or not, tend not to be sexually attracted   
   to each other, yet the other says that individuals who are very   
   closely related (e.g. siblings) who are brought up separately *do*   
   often end up sexually attracted to each other.   
      
   Can you discern any coherent evolutionary pattern in any of that?   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)