Figure 5
From: Caudal autotomy as anti-predatory behaviour in Palaeozoic reptiles
Comparisons of fracture planes through ontogeny in squamates and captorhinids. Caudal vertebrae in juvenile Iguana (ROM R9175) (a–d) have fracture planes that extend through the entire centrum in thin section. During autotomy, these fracture planes facilitate a break in the anterior third of the vertebrae, through the neural arch and spine, to allow the vertebra to split in two (e). Older, larger Iguana (ROM 77408) (f–i) have closed fracture planes and show less frequency of autotomy1. Large anterior caudal vertebrae of captorhinids (ROM 73770) (j–m) similarly possess closed fracture planes in thin section. Abbreviations: cb, cortical bone; nc, neural canal. Anterior is to the left in all of the images.
