- Joseph T Eastman: Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, Ohio, 45701-2979.
Cover illustration. Notothenioid fishes lack swim bladders, but species live temporarily or permanently in the water column. Without swim bladder, skeletal mass becomes a key determinant of buoyancy. In this issue of the Journal of Morphology, Joseph Eastman and coauthors (pp. 841-861 10.1002/jmor.20258) quantify the degree of skeletal ossification in notothenioid fish and discuss it in phylogenetic context. The cover image shows a volume rendered micro-CT image showing extensive bone in the adult skeleton of the non-Antarctic notothenioid Bovichtus diacanthus from Tristan da Cunha. Tissue density is mapped in false color on a spectrum ranging from less dense (cool colors) to more dense (warm colors). Bone is considerably more extensive in B. diacanthus than in Antarctic notothenioids.