Skull morphological variation in a British stranded population of false killer whale (Pseudorca crassidens, Owen 1846): a 3D geometric morphometric approach

The false killer whale (Pseudorca crassidens (Owen, 1846)) is a globally distributed delphinid that shows geographical differentiation in its skull morphology. We explored cranial morphological variation in a sample of 85 skulls belonging to a mixed sex population stranded in the Moray Firth, Scotla...

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Bibliographic Details
Published in:Canadian Journal of Zoology
Main Authors: Vicari, D, Sabin, RC, Brown, RP, Lambert, O, Bianucci, G, Meloro, C
Format: Article in Journal/Newspaper
Language:English
Published: Canadian Science Publishing 2022
Subjects:
Online Access:http://researchonline.ljmu.ac.uk/id/eprint/16917/
https://researchonline.ljmu.ac.uk/id/eprint/16917/8/Skull%20morphological%20variation%20in%20a%20British%20stranded%20population%20of%20false%20killer%20whale.pdf
https://doi.org/10.1139/cjz-2021-0112
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Summary:The false killer whale (Pseudorca crassidens (Owen, 1846)) is a globally distributed delphinid that shows geographical differentiation in its skull morphology. We explored cranial morphological variation in a sample of 85 skulls belonging to a mixed sex population stranded in the Moray Firth, Scotland, in 1927. A three-dimensional digitizer (Microscribe 2GX) was used to record 37 anatomical landmarks on the cranium and 25 on the mandible to investigate size and shape variation and to explore sexual dimorphism using geometric morphometric. Males showed greater overall skull size than females, whereas no sexual dimorphism could be identified in cranial and mandibular shape. Allometric skull changes occurred in parallel for both males and females, supporting the lack of sexual shape dimorphism for this particular sample. Also, fluctuating asymmetry did not differ between crania of males and females. This study confirms the absence of sexual shape dimorphism and the presence of a sexual size dimorphism in this false killer whale population.