  Recent statistical and computational analyses have shown that a genealogical
most recent common ancestor (MRCA) may have lived in the recent past. However,
coalescent-based approaches show that genetic most recent common ancestors for
a given non-recombining locus are typically much more ancient. It is not
immediately clear how these two perspectives interact. This paper investigates
relationships between the number of descendant alleles of an ancestor allele
and the number of genealogical descendants of the individual who possessed that
allele for a simple diploid genetic model extending the genealogical model of
Joseph Chang.
