Macroevolutionary dynamics of dentition in Mesozoic birds reveal no long-term selection towards tooth loss.

ABSTRACT: Several potential drivers of avian tooth loss have been proposed, although consensus remains elusive as fully toothless jaws arose independently numerous times among Mesozoic avialans and dinosaurs more broadly. The origin of crown bird edentulism has been discussed in terms of a broad-scale selective pressure or trend toward toothlessness, although this has never been quantitatively tested. Here, we find no evidence for models whereby iterative acquisitions of toothlessness among Mesozoic Avialae were driven by an overarching selective trend. Instead, our results support modularity among jaw regions underlying heterogeneous tooth loss patterns and indicate a substantially later transition to complete crown bird edentulism than previously hypothesized (∼90 mya). We show that patterns of av

SUBMITTER: Brocklehurst N 

PROVIDER: S-EPMC7973866 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature