Figure 9. Synchronous relative extremums (in percent) of the number of stages (diamonds), diversity of marine organisms (squares), and their extinctions (triangles) compared with relative extremums in the geomagnetic reversal frequency. For the sake of clearness, these values are normalized to a maximum peak of a given characteristic. (a) Data are grouped in 10-Myr intervals. (b) Data are smoothed using a 30-Myr interval.