Modelling the recent common ancestry of all living humans
The journal article " Modelling the recent common ancestry of all living humans " by Rohde, Olson, and Chang (2004) explores the fascinating question of how recently all living humans shared a common ancestor. This seemingly simple question leads to surprising insights into the nature of human population history and genealogy. The authors begin by defining the concept of the most recent common ancestor (MRCA) . This is the individual who is a genealogical ancestor of every person alive today. While intuitively, one might assume this MRCA lived long ago, the authors demonstrate that in a randomly mating population, the MRCA would have lived surprisingly recently. However, the real world is far more complex than a randomly mating population. The key contribution of this paper lies in its exploration of how population substructure affects the timing of the MRCA. Population substructure refers to the fact that humans tend to mate within their own social and geograph...