Patterns of morphospace occupation and mechanical performance in extant crocodilian skulls: a combined geometric morphometric and finite element modeling approach.

摘要: Extant and fossil crocodilians have long been divided into taxonomic and/or ecological groups based on broad patterns of skull shape, particularly the relative length width snout. However, these not quantitatively analyzed in detail, their biomechanical functional implications are similarly understudied. Here, we use geometric morphometrics finite element analysis to explore variation crocodilian morphology those patterns. Our results indicate that shape extant crocodiles is much more complex than previously recognized. Differences snout main components variation, but differences correlated with changes other regions skull. Additionally, there considerable disparity within general classes such as longirostrine brevirostrine forms. For example, Gavialis Tomistoma occupy different parts morphospace implying a significant difference despite fact both traditionally considered longirostrine. Skull also strongly influence mechanical performance skull; narrow morphotypes (e.g., Tomistoma) experience highest amount stress during biting, whereas short Caiman latirostris) least stress. Biomechanical hydrodynamic properties show strong relationship distribution morphospace, phylogeny biogeography weak or no correlation. Therefore, specializations related feeding foraging likely greatest shape.