Variation in air sac morphology and postcranial skeletal pneumatization patterns in the African grey parrot.
3D model
African grey parrot
air sac
anatomical variation
avian
lung
micro‐CT
skeletal pneumatization
Journal
Journal of anatomy
ISSN: 1469-7580
Titre abrégé: J Anat
Pays: England
ID NLM: 0137162
Informations de publication
Date de publication:
07 Oct 2024
07 Oct 2024
Historique:
revised:
13
09
2024
received:
24
11
2023
accepted:
16
09
2024
medline:
7
10
2024
pubmed:
7
10
2024
entrez:
7
10
2024
Statut:
aheadofprint
Résumé
The anatomy of the avian lower respiratory system includes a complex interaction between air-filled pulmonary tissues, pulmonary air sacs, and much of the postcranial skeleton. Hypotheses related to the function and phylogenetic provenance of these respiratory structures have been posed based on extensive interspecific descriptions for an array of taxa. By contrast, intraspecific descriptions of anatomical variation for these features are much more limited, particularly for skeletal pneumatization, and are essential to establish a baseline for evaluating interspecific variation. To address this issue, we collected micro-computed tomography (μCT) scans of live and deceased African grey parrots (Psittacus erithacus) to assess variation in the arrangement of the lungs, the air sacs, and their respective invasion of the postcranial skeleton via pneumatic foramina. Analysis reveals that the two pairs of caudalmost air sacs vary in size and arrangement, often exhibiting an asymmetric morphology. Further, locations of the pneumatic foramina are more variable for midline, non-costal skeletal elements when compared to other pneumatized bones. These findings indicate a need to better understand contributing factors to variation in avian postcranial respiratory anatomy that can inform future intraspecific and interspecific comparisons.
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Subventions
Organisme : Association of Avian Veterinarians
Informations de copyright
© 2024 The Author(s). Journal of Anatomy published by John Wiley & Sons Ltd on behalf of Anatomical Society.
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