The Terrible Lizards podcast has an episode about all things Spinosaur. One of the hosts, David Hone, is a co-author of a recent paper in the journal Palaeontologia Electronica. That paper is entitled "Evaluating the ecology of Spinosaurus: Shoreline generalist of aquatic pursuit specialist?". It challenges some of the theories in other recent papers that proposed that Spinosaurus was a pursuit predator that spent most of its time swimming in relatively deep water. Instead, he with co-author Thomas Holtz propose a wading model, which saw the animal fishing from near shore and shallow waters.
Abstract
The giant theropod Spinosaurus was an unusual animal and highly derived in many ways, and interpretations of its ecology remain controversial. Recent papers have added considerable knowledge of the anatomy of the genus with the discovery of a new and much more complete specimen, but this has also brought new and dramatic interpretations of its ecology as a highly specialised semi-aquatic animal that actively pursued aquatic prey. Here we assess the arguments about the functional morphology of this animal and the available data on its ecology and possible habits in the light of these new finds. We conclude that based on the available data, the degree of adaptations for aquatic life are questionable, other interpretations for the tail fin and other features are supported (e.g., socio-sexual signalling), and the pursuit predation hypothesis for Spinosaurus as a “highly specialized aquatic predator” is not supported. In contrast, a ‘wading’ model for an animal that predominantly fished from shorelines or within shallow waters is not contradicted by any line of evidence and is well supported. Spinosaurus almost certainly fed primarily from the water and may have swum, but there is no evidence that it was a specialised aquatic pursuit predator.
David W.E. Hone. Queen Mary University of London, Mile End Road, London, E1 4NS, UK. d.hone@qmul.ac.uk
Thomas R. Holtz, Jr. Department of Geology, University of Maryland, College Park, Maryland 20742 USA and Department of Paleobiology, National Museum of Natural History, Washington, DC 20560 USA. tholtz@umd.edu