The Common Ancestor?

You are ignoring all of the other ancestors that lived at the same time who also have descendants in the current population. You are ignoring all of the uncommon ancestors.This is a rather simple concept to understand by looking at your grandparents. Your mother's father is your ancestor, but you do not carry his y-chromosome. Does that mean that your mother's father is not one of your ancestors? Your father's mother did not give you your mitochondria, so does that mean that she is not one of your ancestors?A y-chromosome MRCA and a mit-DNA MRCA does not indicate that the human population was founded by a single couple. In fact, the genetic variation elsewhere in our genome argues strongly against it. Mitochondria and y-chromosomes are just 2 genetic markers out of millions in our genome, and the common ancestors for those other markers are going to people other than mit-DNA Eve and Y-chromosome Adam.Added these wonderful images in an edit: Edited by Taq, : No reason given.Edited by Taq, : No reason given.Edited by Taq, : No reason given.

Why Aaron? How did you determine that a person named Aaron was the source of the Y-chromosome?Also, those men also have male ancestors who were alive at the same time as the Y-chromosome MRCA. The Y-chromosome is just one genetic marker out of millions, and many of them will have DIFFERENT MRCA's. A Y-chromosome most recent common ancestor in no way indicates that an entire population was spawned by one man. I guess you are unaware of all the different Y-chromosome haplogroups in the modern population?Human Y-chromosome DNA haplogroup - Wikipedia

That seems quite arbitrary. Why not our common ancestor with all mammals, or all vetebrates? The fixation on chromosome counts is also just as arbitrary. Chromosome number does not define a species. There are mouse species with many different chromosome counts, and there are in fact living humans with 22 pairs of chromosomes that are fit and hale.