Being an Anthropology student, as well as a genealogy enthusiast, I just have to ask myself; What is the probability of any two people sharing a common ancestor? For the sake of simplicity {somewhat} lets just say what are the odds of any person from any of the non-isolated populations of Europe, Asia, Africa and their descendant diaspora. In other words, odds do I, an average American have of sharing a common ancestor with any Asian, European or African within 16-20-30 generations? If anyone has any statistical sources they wish to cite it would be useful.