Joshua’s paper generated significant conversation at the Conference. This is because practically everyone realized that his proposal provided helpful insights, and perhaps even a helpful corrective, in several areas. He makes the important distinction between genetics and genealogy. If I’m understanding his argument correctly, he makes two points: 1) We have little or no discernible genetic evidence of most of our ancestors beyond, say, 1000 years ago. So most of our ancestors are “genetic ghosts.” And 2) if someone in the ancient world (i.e., before the time of Christ) had any children at all, then he or she probably is the direct ancestor of all.
For scientific laypersons like me, this is extremely helpful. It means (I think) that I shouldn’t get too distracted by attempts to locate a common genetic ancestor (i.e., a Mitochondrial Eve or a Y-Adam), nor should I wonder if it is possible if an ancient couple could be the genealogical ancestors of all living humans.