Isometry in mesosaurs: implications for growth patterns in early amniotes

Jorge Ferigolo,Graciela Piñeiro,Pablo Nuñez Demarco

doi:10.4202/app.00931.2021

Abstract

Isometry in mesosaurs: implications for growth patterns in early amniotes

Highlights

Mesosaurs were small amphibious tetrapods that lived in western Gondwana during the Early Permian or even earlier, when temperate Permo-Carboniferous conditions initiated after the glaciations that affected the southern region of Pangea
The analyses revealed that all mesosaur bones scale remarkably close to a model of geometrical similarity, and that this pattern is strong in long bones and in the skull
The well-defined isometry, and the high interrelation between metatarsals and phalanges permit us to suggest that the mesosaur hind limb is subject to notable modularity

Summary

Introduction

Mesosaurs were small amphibious tetrapods that lived in western Gondwana during the Early Permian or even earlier, when temperate Permo-Carboniferous conditions initiated after the glaciations that affected the southern region of Pangea. We applied traditional linear regression morphometrics to analyse proportions of both the skull and limb bones in more than 100 mesosaur specimens.

Results

Conclusion