Tensor tomography of shark vertebral centra tissue

With rapidly accelerating climate change, populations of many marine species are at high risk, especially slowly reproducing apex predators like sharks. Growth bands in shark vertebral centra are used to estimate age, and numerous sub-bands exist, confounding band counts and negatively affecting population estimates and fisheries management. Centra consist of mineralized trabeculae of 4.5-13 µm thicknesses, and varying trabeculae thickness/spacing produces growth band contrast and the transition between microstructural zones. Whether crystallographic texture also varies across bands or other transition zones at the trabecular level is unknown. 3D, quantitative texture maps resolving individual trabeculae will improve understanding of shark growth and of centrum mechanical functionality. Tensor tomography with 3 µm sampling at ID-13 will be applied to shark centra tissue from species of two phylogenetic families.