Diving dinosaurs? Caveats on the use of bone compactness and pFDA for inferring lifestyle.

The lifestyle of spinosaurid dinosaurs has been a topic of lively debate ever since the unveiling of important new skeletal parts for Spinosaurus aegyptiacus in 2014 and 2020. Disparate lifestyles for this taxon have been proposed in the literature; some have argued that it was semiaquatic to varying degrees, hunting fish from the margins of water bodies, or perhaps while wading or swimming on the surface; others suggest that it was a fully aquatic underwater pursuit predator. The various proposals are based on equally disparate lines of evidence.

is not an aquatic dinosaur.

A predominantly fish-eating diet was envisioned for the sail-backed theropod dinosaur when its elongate jaws with subconical teeth were unearthed a century ago in Egypt. Recent discovery of the high-spined tail of that skeleton, however, led to a bolder conjecture that was the first fully aquatic dinosaur. The 'aquatic hypothesis' posits that was a slow quadruped on land but a capable pursuit predator in coastal waters, powered by an expanded tail.

Wing Shape in Waterbirds: Morphometric Patterns Associated with Behavior, Habitat, Migration, and Phylogenetic Convergence.

Wing shape plays a critical role in flight function in birds and other powered fliers and has been shown to be correlated with flight performance, migratory distance, and the biomechanics of generating lift during flight. Avian wing shape and flight mechanics have also been shown to be associated with general foraging behavior and habitat choice. We aim to determine if wing shape in waterbirds, a functionally and ecologically diverse assemblage united by their coastal and aquatic habitats, is correlated with various functional and ecological traits.