This is a simulation of the basic demographic / genealogical process. Individuals are born and individuals die. This causes lineages to branch and to disappear, and causes the population to share a common ancestor at some time in the past. The coalescent provides a mathematical description of these patterns of ancestry.
Individuals are represented as circles. Layout is taken care of through simple physics. Each individual is given a charge and Coulomb's law is used to for repulsion. The edges of the screen are also charged.
Individuals leave a trace of where they used to be. I was pleasantly surprised to have the physical location of a lineage cleanly reveal its genealogical history.
Press H to bring up a listing of commands.