2018, Aureliano and colleagues presented a possible scenario for the food web of the Romualdo Formation. The researchers proposed that spinosaurines from the formation may have also preyed on terrestrial and aquatic crocodyliforms, juveniles of their own species, turtles, and small to medium-sized dinosaurs. This would have made spinosaurines apex predators within this particular ecosystem. Aquatic habits Many spinosaurs likely had semiaquatic habits, as has been shown in studies using techniques like isotope analysis and bone histology. It has been found that they probably took advantage of aquatic prey and environments (usually marginal and coastal habitats) to occupy a distinct ecological niche, therefore avoiding competition with more terrestrial theropods. Spinosaurines appear to have been more adapted for such lifestyles than baryonychines. A 2018 study by British paleontologist Thomas M. S. Arden and colleagues examined the morphology of spinosaurine skull bones for possible aquatic traits. They found that the frontal bones of Irritator, Spinosaurus, and Sigilmassasaurus were similar in being arched, concave on top, and narrowed at the front; features that would have resulted in the eyes being positioned further up on the head than in other theropods. In particular, the broad lower jaw and narrowed frontals of Irritator resulted in the orbits facing at a steep incline towards the midline of the skull, whereas most theropods had laterally facing orbits. These traits would have permitted the animal to see above the waterline when submerged. In 2018, Aureliano and colleagues conducted an analysis on the Romualdo Formation tibia fragment. CT scanning of the specimen in the University of San Carlos revealed the presence of osteosclerosis (high bone density). This condition had previously only been observed in Spinosaurus aegyptiacus, as a possible way of facilitating submersion in water by making its bones heavier. The presence of this condition on the Brazilian leg fragment showed that compact bones had already evolved in spinosaurines at least 10 million years before the appearance of Spinosaurus in Morocco. According to phylogenetic bracketing—a method used to infer unknown traits in organisms by comparison with their relatives—osteosclerosis therefore might have been the norm in the Spinosaurinae. The significance of these traits was questioned in a later 2018 publication, where Canadian paleobiologist Donald Henderson argued that osteosclerosis would not have changed a theropod's buoyancy to a significant extent. Neuroanatomy and senses In 2020, German paleontologist Marco Schade and colleagues analyzed the anatomy of the holotype skull braincase through CT