I have put up on my site http://knordtvedt.home.bresnan.net some output of a program which does simulation of how a demographic tree of descendants develops (or goes extinct). It is called “FirstNode.txt” We can tame the stocastic fluctuations of mutations to a good degree for prediction or “tree tagging” purposes by using a large number of STRs in our haplotypes --- each STR being an independent “clock” of sorts running through the tree. But when considering a specific tree, there is basically nothing that can be done to tame the early generation stocastic fluctuations of reproduction --- a tree first has just two people, then three, then four....., and such small numbers have large stocastic fluctuations in their reproductive outputs. As a result any specific male in a population has very huge variation in what his descendant population will be in the future, in addition to the ultimate demographic lottery of extinction or not of his descendant line. Extinction probabilities are quite large even for a growing population. The purpose of looking at generational distance to “first node” was because that is an important parameter in relating tree coalescence age to tree tmrca. While we don’t know how far apart these ages are for an ancient, pre-paper-genealogy tree, I was hoping some experience about coalescence age versus tmrca could be collected by these simulation studies.