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

Brocklehurst, Neil and Field, Daniel J. (2021) Macroevolutionary dynamics of dentition in Mesozoic birds reveal no long-term selection towards tooth loss. iScience. p. 102243. ISSN 2589-0042 DOI https://doi.org/10.1016/j.isci.2021.102243

	Text PIIS258900422100211X.pdf - Accepted Version Available under License Creative Commons Attribution. Download (12MB)
Preview	Image (Graphical abstract) 1-s2.0-S258900422100211X-fx1_lrg.jpg - Accepted Version Download (211kB) | Preview

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 avialan tooth loss adhere to Dollo’s law and suggest that the exclusive survival of toothless birds to the present represents lineage-specific selective pressures, irreversibility of tooth loss, and the filter of the K–Pg mass extinction.

Item Type:	Article
Uncontrolled Keywords:	2021AREP; IA77
Subjects:	04 - Palaeobiology
Divisions:	04 - Palaeobiology 07 - Gold Open Access
Journal or Publication Title:	iScience
Page Range:	p. 102243
Identification Number:	https://doi.org/10.1016/j.isci.2021.102243
Depositing User:	Sarah Humbert
Date Deposited:	05 Mar 2021 16:44
Last Modified:	05 Mar 2021 16:44
URI:	http://eprints.esc.cam.ac.uk/id/eprint/6024

Actions (login required)

View Item