Figure 7.  Comparison of radiolarian evolutionary (A-C) and environmental history (D-F, Mackensen et al. 1992 data only) in Antarctic Neogene. Evolution curves are composites of the different authors' data sets, with cut-points of 5 and 11 Ma. Gray shading indicates the two major episodes of environmental change between 15-13 Ma and 7-4 Ma. A - first occurrences in radiolarian faunas. B - last occurrences. C - Diversity. D - ¹³C of planktonic (red) and benthic (blue) foraminifera . E - Percent CaCO₃ in sediment. F - ¹⁸O of planktonic (green) and benthic (blue) foraminifera.