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Cited by 43Paleontology and Evolutionary BiologyEvolution and Paleontology StudiesComparative Animal Anatomy Studies

Inferring lifestyle for Aves and Theropoda: A model based on curvatures of extant avian ungual bones

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Cobb, Savannah Elizabeth, Sellers, William I.·2020·PLOS ONE
DOI 10.1371/journal.pone.0211173PMC PMC7001973

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Abstract

Claws are involved in a number of behaviours including locomotion and prey capture, and as a result animals evolve claw morphologies that enable these functions. Past authors have found geometry of the keratinous sheath of the claw to correlate with mode of life for extant birds and squamates; this relationship has frequently been cited to infer lifestyles for Mesozoic theropods including Archaeopteryx. However, many fossil claws lack keratinous sheaths and thus cannot be analysed using current methods. As the ungual phalanx within the claw is more commonly preserved in the fossil record, geometry of this bone may provide a more useful metric for paleontological analysis. In this study, ungual bones of 108 birds and 5 squamates were imaged using X-ray techniques and a relationship was found between curvatures of the ungual bone within the claw of pedal digit III and four modes of life; ground-dwelling, perching, predatory, and scansorial; using linear discriminant analysis with weighted accuracy equal to 0.79. Our model predicts arboreal lifestyles for Archaeopteryx and Microraptor and a predatory ecology for Confuciusornis. These findings demonstrate the utility of our model in answering questions of palaeoecology, the theropod-bird transition, and the evolution of avian flight. Though the metric exhibits a strong correlation with lifestyle, morphospaces for PD-III curvatures overlap and so this metric should be considered alongside additional evidence.

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  • Analyses of pedal claw curvature lack consensus, which may at least partially reflect differences in how curvature is quantified.

    “Analyses of pedal claw curvature lack consensus, which may at least partially reflect differences in how curvature is quantified.”

    From The ecology of Archaeopteryx (2026) · cites this paper as [69]

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Authors
Cobb, S. E., & Sellers, W. I.
Affiliations
University of Manchester (GB)
Corresponding author
  • Cobb, Savannah Elizabeth
  • Sellers, William I.
ORCID
Venue
PLOS ONE
Publisher
Public Library of Science (PLoS)
Published
2020-02-05
Volume
15
Issue
2
Pages
e0211173
ISSN
1932-6203 (ISSN-L)
DOI
10.1371/journal.pone.0211173
PMC
PMC7001973
OpenAlex
W3002552645
Cited by
43
References
15
Citations by year
2026: 4 · 2025: 9 · 2024: 4 · 2023: 14 · 2022: 4 · 2021: 6 · 2019: 2
FWCI
3.44
Type
journal article
Language
en
Open access
Licence
Locations
  • PLoS ONE (publishedVersion, cc-by)
  • bioRxiv (Cold Spring Harbor Laboratory) (acceptedVersion, cc-by)
  • Europe PMC (PubMed Central) (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • Research Explorer (The University of Manchester) (publishedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
  • Figshare (submittedVersion, cc-by)
  • Research Explorer (The University of Manchester) (submittedVersion)
Funders
Natural Environment Research Council (NE/R011168/1)
Topics
  • Physical Sciences › Earth and Planetary Sciences › Paleontology › Paleontology and Evolutionary Biology
  • Physical Sciences › Earth and Planetary Sciences › Paleontology › Evolution and Paleontology Studies
  • Health Sciences › Medicine › Urology › Comparative Animal Anatomy Studies
Keywords
distal phalanx, Archaeopteryx, Microraptor, Confuciusornis, perching, paleoecology
MeSH terms
Animals, Birds, Fossils, Hoof and Claw, Predatory Behavior, Bones of Lower Extremity

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