I watched a programme last night in which the comedian Eddie Izzard traced his ancestry. More precisely he followed a trail across continents worked out by geneticists. It was, in truth, not about Izzard and his family, but the family of man, Homo Sapiens Sapiens. Last night it was the migration of the female line out of Africa, through Asia into Europe. Over time, naturally, the population whose movement was followed got smaller and smaller, as the human race divided and the various branches went their separate ways.
There is another programme tonight following Izzard's male line.
One thing I learned - all blue eyed people descend from a common ancestor way back in time, and at some stage were settled on the shores of the Black Sea. I hear the call of the Eurasian Steppe.
The blue eyes are linked, in some manner which I could not understand, with the beginning of man's adoption of milk, i.e., animal milk, as part of his diet. Apparently not everyone adapted easily to the new food, but the development of the blue eye colour was a sign of successful adaption.

[Small digression: the Greek for milk is gala. One Greek word for blue is galanos, which also means 'blue-eyed'. I think it is also a Greek surname. It's often noted that the ancient Greeks didn't have a word for blue, hence Homer's "wine-dark sea".]

I'd love to get a personal DNA reading, such as can trace one's ancestry back before surnames gave a clue to one's ancestry; before nations were formed and borders drawn on maps; before recorded history perhaps. I keep checking to see if the fee charged for this service has yet matched my ability to pay up and order.