Abstract
The bony palate of palaeognaths was long thought to retain the plesiomorphic condition for crown birds, but recent fossil evidence suggests that aspects of palaeognath palate morphology are derived from a neognath-like ancestral state. Relatedly, heterochronic shifts have been proposed as the mechanism underpinning major evolutionary transitions in avian palate morphology, but this hypothesis has never been explicitly tested with a broad phylogenetic assessment of morphological variation through avian ontogeny. Here, we assess palatal changes through post-hatching ontogeny across the major extant avian subclades and find that although palaeognaths exhibit distinct ontogenetic changes relative to neognaths, no signatures of heterochrony underlie these developmental differences. However, we find that important patterns of morphological change appear to be dictated by variation in developmental mode. Our results clarify the ontogenetic mechanisms driving avian palate disparity and illustrate the influence of developmental mode on the evolvability of a key morphofunctional system in the avian skull.
Data availability
The 3D models and landmark data generated in this study have been deposited on Figshare (https://doi.org/10.6084/m9.figshare.29618981). All other data generated in this study (e.g., PC scores, angles, and dataset information) are provided in the Supplementary Information. Source data are provided with this paper.
Code availability
The R code used to analyse the data generated in this study has been deposited on Figshare (https://doi.org/10.6084/m9.figshare.29618981).
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Acknowledgements
We are indebted to Matt Lowe (UMZC) and Judith White (NHM) for assistance with specimens, and Keturah Smithson (Cambridge Biotomography Centre) for CT scanning assistance. We would like to thank Michel Beaud and Boris Baeriswyl (Musée d’Histoire Naturelle Fribourg), Manuel Schweizer and Reto Hagmann (Naturhistorisches Museum Bern) for giving access to specimens and Sharon Grant for giving access to MorphoSource specimens. We thank Annabel Hunt (Cambridge) for insight into hemipterygoid homology guiding our landmark applications. We would like to thank the anonymous reviewers for their critical evaluation of our work, which enabled us to significantly improve our manuscript. This work was funded by UKRI grant MR/X015130/1 (D.J.F) and the SNSF grant P500PN_214284 (O.P). For the purpose of open access, the authors have applied a Creative Commons Attribution (CC BY) licence to any Author Accepted Manuscript version arising.
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O.P. and D.J.F. conceived and designed the project. O.P. performed digital segmentation of the bones; designed the analytical framework with input from J.B. and conducted the geometric morphometric analyses with input from G.N.; O.P. designed the figures and wrote the original manuscript with input from all the authors (G.N., J.B., D.J.F.). O.P. and G.N. collected part of the dataset, while D.J.F. collected and curated the remaining data. O.P and D.J.F. secured funding for the project.
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Plateau, O., Navalón, G., Benito, J. et al. Developmental underpinnings of morphological disparity in the avian bony palate. Nat Commun (2026). https://doi.org/10.1038/s41467-026-69576-w
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DOI: https://doi.org/10.1038/s41467-026-69576-w
