Figure 4

Synthesis of published shell mass data plotted against new estimates of seawater density. Data are for G. bulloides shells (300–355 μm) and Mg/Ca - δ¹⁸O derived in-situ densities from N. Atlantic and S.W. Pacific sites (p < 0.001, n = 312). The dashed lines around the regression line indicate the 95% level of confidence. Data are grouped based on marine isotopic stage (MIS). The correlation between size normalized weight to salinity or temperature alone was R² = 0.44 (p < 0.001, n = 315) and R² = 0.03 (p > 0.1, n = 315) respectively, while temperature and salinity were uncorrelated (p > 0.05).