[TheHound]

Well maybe, but I seem to remember that the Neanderthals became the Basques.

How the Neanderthals became the Basques

[blam]

The Neanderthal Theory

[RouxStir]

The article you link states regarding Rh factors:
"antibodies to Rh+ blood in the woman which typically attack the blood of her subsequent Rh+ children, causing them to miscarry, be stillborn, or die shortly after birth (infant haemolytic disease [6]). This phenomenon is unknown elsewhere in nature..."

This type of blood antibody reaction is known to occur in other animals. And only a very few other animals have been studied for this. So it is possible that this occurs in many animals other than humans.