No I don't know about those white deer - a mutant isolated population - how interesting, genetically speaking I mean. I shall check that out on Wiki...
In the end I went back to a piece of stunning rock art from Gardom's Edge
http://www.themodernantiquarian.com/post/13459/gardoms_edge.html
which since Andrew Common Era told me about has etched itself in my mind's eye.
I was very interested to see that at Eggerness we get antelope petroglyphs; common in Scandinavia, all over Africa, but not here.