drag and aquatic instability from the sail, as well as the rigid trunk and seemingly scarcely-muscled tail. Animals like crocodilians require a flexible body in order to move through the water and make sharp turns when chasing prey, and this is directly contradicted by Hone and Holtz's findings. A 2022 study by Fabbri et al., made comparisons of Spinosaurus bone structure and compared it to that of Baryonyx and Suchomimus. The study revealed that Spinosaurus and Baryonyx had dense bones, which allowed them to dive and pursue prey underwater. Compared to these, Suchomimus had more hollow bones, suggesting it preferred to hunt in shallow water. These findings also suggest that various spinosaurid genera were more ecologically disparate than previously believed, as some were better suited to hunting in subaqueous environments than other, closely related genera. In the same year, contradicting the study by Fabbri and colleagues, Sereno and his colleagues suggested that Spinosaurus was wholly bipedal on land and an unstable, slow moving surface swimmer in deep water. Their results, taken from reconstructing a CT model of the skeleton, and then adding internal air and muscles. Their results, coupled with fossils from Spinosaurus that showed it also lived further inland along rivers and lakes, suggest it was a semi-aquatic, ambush piscivore that preferred waterside environments both along the coasts and further inland along rivers and lakes. Simultaneously, they suggested that the large tail fin was probably utilized more for display than swimming, as tails in living animals have the same function when they possess comparably tall neural spines. Locomotion and posture Although traditionally depicted in the scientific community as a biped, Spinosaurus was often depicted in the mid-20th century as an obligate quadruped akin to Dimetrodon. Starting in the mid-1970s, it was hypothesised Spinosaurus was at least an occasional quadruped, bolstered by the discovery of Baryonyx, a relative with robust arms. Because of the mass of the hypothesized fatty dorsal humps of Spinosaurus, Bailey (1997) was open to the possibility of a quadrupedal posture, leading to new restorations of it as such. Theropods, including spinosaurids, could not pronate their hands (rotate the forearm so the palm faced the ground), but a resting position on the side of the hand was possible, as shown by fossil prints from an Early Jurassic theropod. The hypothesis that Spinosaurus had a typical quadrupedal gait since fell out of favour, however it was still believed