evolutionary mass
1.THE EVOLUTIONARY TRACK IN THE H-R DIAGRAM OF MODEL STARS OF 1.2 SOLAR MASS
2.The mass extinction and Lazarus events of three representative categories(graptolite,brachiopod,and conodont)within the strata across the late Ordovician and Silurian boundary was discussed recently. It is assured that the base of persculptus is a remarkable bio evolutionary turnover surface. Consequently,to choose Wangjiawan Ordovician/Silurian section in Yichang as a stratotype with persculptus as the biomarker for the revised boundary is corresponding to the bio evolutionary events.
