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Old 09-23-2012, 08:44 PM
President Johnny Gentle President Johnny Gentle is offline
Join Date: May 2007
Posts: 583
Originally Posted by Jonathan Chance View Post
I think you'd need to find some means of dealing with consanguinuity to make that calculation accurate. You find that just a few people like me, with genetic stock pulling from:

Northern European
Middle Eastern
Sub-saharan Africa
Native American

And suddenly there's a LOT more ways to make it all come together with less than 50th-level cousins.
Exactly. Going back 50 generations would imply that we have about 1 quadrillion great*48 grandparents each. Current estimates say that there have been around 100 billion humans ever. The estimate I've seen for the world population in the year 1000 is 400 million.

The fact that the 1 quadrillion ancestors all have to be taken from this same group of 400 million (many of whom have no living descendants) makes the 50th cousin claim highly plausible.