With over 150 species, catsharks make up the largest family of sharks, but are generally unexplored, particularly in areas relating to nurseries and reproductive biology. Most catshark species are oviparous (lay eggs), but a few exhibit aplacental viviparity, in which the shark gives live birth after the embryo has developed inside the mother aplacentally. My project involves CT scanning and taking cross-sectional images of 5 representative catshark species (C.cephalus, G. attenuatus, H. regani, P. melanobranchus, and H. edwarsii). Specimens will be obtained from the Florida Museum’s Ichthyology Collection and the Smithsonian Museum of Natural History. I will reconstruct the scans using the computer software VGStudio to distinguish the pelvic structure from other body tissue, and then assess the dimensions to determine percentage of total body mass. Ratios obtained will then be compared to reproductive method to determine if there is an association. Observations regarding this type of morphology are important in understanding broader transformations and patterns of growth in shark species, and could eventually be extended to other marine animals as well.