Fig. 6

Mean radius of the upper osculating circle (R up) in keel view (μm) per sample through time (Ma) at Hole 925B for G. menardii (a), G. limbata (b), and G. multicamerata (c). In d means of R up of the three groups are compared to each other. See Fig. 5 for explanation of symbols. For explanation of the radius of the upper osculating circle R up refer to Fig. 4. Measurements and statistics can be read from Tables 4a–c and 5a–c in the electronic supplementary materials