Constraints and adaptations in crocodyliform skull evolution

2025/11/01 by Ananth Srinivas, Jen A. Bright, John A. Cunningham +5 · 2 voices · 1 citation
Earth and Planetary Sciences · #Paleontology and Evolutionary Biology #Evolution and Paleontology Studies #Paleontology and Stratigraphy of Fossils

paper · doi:10.1098/rspb.2025.1773

Abstract

Crocodyliforms display a diverse range of skull morphologies through their evolutionary history. Extant crocodilians possess platyrostral (broad and flat) snouts, thought to be sub-optimal for resisting feeding loads due to the conflicting demands of feeding and hydrodynamic constraints. In contrast, numerous Mesozoic crocodyliforms possessed oreinirostral (dome-shaped) skulls, were terrestrial and hence free from hydrodynamic constraint. This study aims to examine the role of function in determining skull shape in crocodyliforms and assesses the difference in stress resistance between oreinirostral and platyrostral taxa. We hypothesize that in the absence of hydrodynamic constraints, oreinirostral taxa have skulls that are better suited for resisting feeding-induced loads. Using finite element analysis, we evaluated biomechanical performance in oreinirostral notosuchian taxa Baurusuchus salgadoensis , Montealtosuchus arrudacamposi and Caipirasuchus paulistanus , compared to the extant platyrostral Alligator mississippiensis , Crocodylus niloticus and Paleosuchus palpebrosus . Results show that oreinirostral morphologies are comparatively better suited for resisting forces generated during feeding, with increased muscular efficiency, supporting the hypothesis that hydrodynamic constraints influence crocodyliform skull evolution.

Citations

• Widespread convergence towards functional optimization in the lower jaws of crocodile-line archosaurs
• For a while, crocodile: crocodylomorph resilience to mass extinctions
• Paleobiology of Herbivorous Dinosaurs

Cited by

• Phylogenetically‐informed estimates of notosuchian (Archosauria, Crocodylomorpha) body size and the challenges of inferring macroevolutionary patterns in extinct groups

Discussions

• Our new paper in @royalsocietypublishing.org is out now We show that modern crocodiles evolved flatter and weaker skulls from domed ancestors to adapt to life in water, trading skull strength for str [bsky, 27 points, 2 comments]
• A new paper by Ananth Srinivas and colleagues shows that modern crocodiles evolved flatter and weaker skulls from domed ancestors to adapt to life in water, trading skull strength for streamlining. d [bsky, 1 points, 0 comments]

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