MODELING THE GENETIC ARCHITECTURE OF MODERN POPULATIONS

This article summarizes recent genetic evidence about the population h istory of our species. There is a congruence of evidence from differen t systems showing that the genetic effective size of humans is about 1 0,000 reproducing adults. We discuss how the magnitude and fluctuation of this number over time is important for evaluating competing hypoth eses about the nature of human evolution during the Pleistocene. The d ifferences in estimates of effective size derived from high mutation r ate and low mutation rate genetic systems allow us to trace broad-scal e changes in population size. The ultimate goal is to produce a compre hensive history of our own gene pool and its spread and differentiatio n over the world. The genetic evidence should also complement archaeol ogical evidence of our past by revealing aspects of our history that a re not readily visible from the archaeological record, such as whether hominid populations in the Pleistocene were different species.