Ah sorry, I missed that quote in your prior post. Now I'm feeling pretty silly, that's one of the papers I was looking at when I looked up the subject. Thanks for that, it's interesting stuff.

One thing I would note there though is the fact that the Dark Elves are an immortal race would probably entail a much slower evolutionary rate than humans given the time between generations is likely longer. If you call a human generation 30 years then there are ~15 generations in those 500 years if elves have babies half as frequently than humans than it may take 1000 years to see a change. 

Also worth noting is we're both looking at this from a very scientific perspective and a lot of science, particularly evolution breaks down in most fantasy settings.
[@Myrna Minkoff]