Fig. 7

Mean spiral convexity (a) as seen in keel view (μm) through time (in Ma) at Hole 925B for G. menardii (a), G. limbata (b), and G. multicamerata (c). In d mean spiral convexities of the three groups are compared to each other. Same explanation for symbols as in Fig. 5. Horizontal bars in a–c are quartile ranges, while in d horizontal bars represent ±95 % confidence intervals around the means. For explanation of spiral convexity (a) refer to Fig. 4. Measurements and statistics can be read from Tables 4–c and 5–c in the electronic supplementary materials