Spinosaurus aegyptiacus
Spinosaurus aegyptiacus. Art by Gustavo Monroy-Becerril, 2020. Wikimedia Commons.

A new study suggests that Spinosaurus, the weird sailbacked theropod dinosaur widely considered to be an aquatic predator, may have been a wader rather than a swimmer. “The purported arguments that Spinosaurus was some croc-like or even stem-whale like animal spending the vast majority of its time in water, and the way it has been illustrated swimming in deep water, and even diving and pursuing fish does not hold up to scrutiny. Instead, a wading model of a more heron- or stork-like animal that spent a lot of time in and around water, but fundamentally fished while standing rather than swimming, is supported.” The authors’ argument is based on Spinosaurus’s physiology, which doesn’t, in their view, support fast swimming, and is more like other theropods than crocodilians.