This might be very interesting. Red hair and light skin go together. The adaptation appears to be related to life at high latitudes, such as Europe. It allows the skin more effectively to synthesize Vitamin D, particularly if much of the body is covered with clothing because of the cold.
I suspect that Neanderthals and modern humans were able to interbreed, but there is no longer any way to test this hypothesis by the usual means. If the two groups could not interbreed, and the Neanderthals and modern humans independently developed light skin for life in foggy, cold, northern latitudes, this would be a case of parallel evolution.
Of course, if you still think that the Earth and the whole Universe were formed in 4,004 BC, you will have trouble making sense out of all this.
Not all cave men were Neanderthals. The men who painted the fine pictures on the walls of the caves in southern France and northern Spain were Cro Magnon, which is a racial type of modern men. There is good evidence that they have left modern descendants.
The Neanderthals, on the other hand, were heavier-boned than modern humans, and had skull characteristics which would be very distinctive. They probably were muscular enough to be able to make short work of even our most grisly looking, steroid-enhanced pro-wrestlers. So why did the Neanderthals die out?
Perhaps global warming got them! ;-)
I don’t think they did die out. They were absorbed within the rest of the human race. Every now and then, a throwback pops up. They are still here..............
Given access to appropriate technology, I can adapt to any environement.
OTOH, no amount of technology will allow me to adapt to any environmentalists.
Ergo, it was Global Warmers, not Global Warming that did them in.