FIGURE 8 in Holocephalan (Chondrichthyes) dental plates with hypermineralized dentine as a substitute for missing teeth through developmental plasticity

FIGURE 8 Chimaera monstrosa, μCT-scans, sub-adult upper dentitions (a) from Figure 1 and (b) from Figure 3a–e, with the rod series explained as whitlockin formed to a timed order at the aboral surface in the trabecular dentine, determined by a dental epithelium, where on the lingual side ridges of the outer dentine layer form (Figure 8b, also Figures 1a, 2b and 3d–e). (a) Partially segmented upper dentition (Avizo) showing three rods of the anterior plate, 2 aligns with the rods of the posterior plate, 0 forms in the symphyseal segment of the plate, 1 and 2 along the labial ridge. (b) Anterior dental plate with five rods and a coloured overlay to explain the co-incidence of ridges with rods (0–4). Colours show the tissue types seen in a virtual section relative to the surface anatomy of the oral and lingual surfaces: whitlockin, orange; trabecular dentine, lime green; sclerotic osteodentine dentine, olive green; wear surface of the sclerotic dentine, moss green. Extent of wear surface is double arrow in Figure 7a. Abbreviations, in previous figures