Figure 5 in Ontogenetic development of the European basal aquatic turtle Pleurosternon bullockii (Paracryptodira, Pleurosternidae)

Figure 5. Shape differences of the nuchal of Pleurosternon bullockii (Paracryptodira, Pleurosternidae), taking into account specimens from the Berriasian (Early Cretaceous) of Swanage (Dorset, England). (a–b) Principal component analysis (PCA). Wireframes indicate the main shape changes in each PC; the light blue concerns the average shape, whereas the dark blue is the shape variance related to the extreme of variation along the axis. (c) Transformation grids to visualize shape deformation relative to the first three principal components. Abbreviations: C, CAMSM; D, DORCM; N, NHMUK.