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Cited by 3Paleontology and Evolutionary BiologyFossil Insects in AmberEvolution and Paleontology Studies

Wing morphology of Anchiornis huxleyi and the evolution of molt strategies in paravian dinosaurs

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Kiat, Yosef, Wang, Xiaoli, Zheng, Xiaoting, Wang, Yan, O’Connor, Jingmai·2025·Communications Biology
DOI 10.1038/s42003-025-09019-2PMC PMC12638977
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Abstract

As one of the most diverse terrestrial amniote clades, Aves has attracted enormous interest regarding its Jurassic origins and the evolutionary transition from terrestrial to volant in theropod dinosaurs. While abundant research has focused on the skeletal transformations associated with the emergence of flight ability, fewer studies have documented the changes to the soft tissues forming the airfoil itself. Newly emerging information concerning the wing structure in pennaraptorans highlights unexpected complexity in the evolution of wing-like structures in non-volant theropods that complicate efforts to understand the origins of flight. No taxon exemplifies this better than Anchiornis, controversial with regards to its flight abilities and phylogenetic position, alternatively regarded as volant or non-volant, and as an avialan or as a troodontid. Here we provide new information concerning the wing structure of this key taxon including temporary changes due to molt based on nine specimens. Anchiornis preserves the first evidence of an irregular molt in a non-avian pennaraptoran, which, together with the unique wing structure, indicates flightlessness. The plumage diversity reflected by this new information highlights the significant gaps in our understanding of the evolution of the avian wing and the ability of new discoveries to drastically alter current interpretations.

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  • Anchiornis was non-volant.

    “it is increasingly clear from the morphology of the skeleton, forelimb feathers, molt pattern, and ontogenetic changes in proportions that this taxon was non-volant [2, 4-6]”

    From The ecology of Archaeopteryx (2026) · cites this paper as [4]

  • Anchiornis exhibits an irregular molt.

    “However, comparison with volant paravians Microraptor and Confuciusornis strongly suggests the remiges would have molted sequentially [110, 111] whereas the non-volant Anchiornis exhibits an irregular molt [4].”

    From The ecology of Archaeopteryx (2026) · cites this paper as [4]

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Cited by

Sorted by citations

Authors
Kiat, Y., Wang, X., Zheng, X., Wang, Y., & O’Connor, J.
Affiliations
  • Tel Aviv University (IL)
  • Linyi University (CN)
  • Shandong Pingyi Tianyu Museum of Natural History (CN)
Corresponding author
  • Kiat, Yosef
  • Wang, Yan
ORCID
Venue
Communications Biology
Publisher
Springer Science and Business Media LLC
Published
2025-11-21
Volume
8
Issue
1
Pages
1633-1633
ISSN
2399-3642 (ISSN-L)
DOI
10.1038/s42003-025-09019-2
PMC
PMC12638977
OpenAlex
W4416470642
Cited by
3
References
10
Citations by year
2026: 3
FWCI
2.11
Type
journal article
Language
en
Open access
Licence
Locations
  • Communications Biology (publishedVersion, cc-by-nc-nd)
  • Europe PMC (PubMed Central) (publishedVersion, cc-by-nc-nd)
  • PubMed (publishedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Funders
  • National Natural Science Foundation of China (41402017, #41688103)
  • Natural Science Foundation of Shandong Province (ZR2020MD026)
Topics
  • Physical Sciences › Earth and Planetary Sciences › Paleontology › Paleontology and Evolutionary Biology
  • Life Sciences › Agricultural and Biological Sciences › Ecology, Evolution, Behavior and Systematics › Fossil Insects in Amber
  • Physical Sciences › Earth and Planetary Sciences › Paleontology › Evolution and Paleontology Studies
Keywords
Anchiornis huxleyi, wing morphology, molting, plumage, flightlessness, troodontids, theropod dinosaurs
MeSH terms
Animals, Biological Evolution, Flight, Animal, Fossils, Phylogeny, Wings, Animal, Dinosaurs

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