New embryological and palaeontological evidence sheds light on the evolution of the archosauromorph ankle.

ABSTRACT: The homology and evolution of the archosaur ankle is a controversial topic that has been deeply studied using evidence from both extinct and extant taxa. In early stem archosaurs, the astragalus and calcaneum form the ancestral proximal tarsus and a single ossification composes the centrale series. In more recent stem archosaurs, the centrale is incorporated to the proximal row of tarsals laterally contacting the astragalus. This bone is subsequently lost as an independent ossification before the last common ancestor of birds and crocodilians, but the evolutionary fate of this element remains mostly unexplored. Here, we integrate embryological and palaeontological data with morphogeometric analyses to test the hypothesis of loss of the centrale or, alternatively, its incorporation into the

SUBMITTER: Blanco MVF 

PROVIDER: S-EPMC7083827 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature