Publication
Title
Looking back over the shoulder : new insights on the unique scapular anatomy of the tapir (Perissodactyla: Tapiridae)
Author
Abstract
The musculoskeletal anatomy of the shoulder of many ungulates has been inferred from veterinary model taxa, with uniformity in muscle arrangements and attachment sites often assumed. In this study, I investigated the muscular and osteological anatomy of tapirs and their relatives (Perissodactyla: Tapiroidea), using a combination of gross dissection and digital imaging (photography and laser surface scanning). Dissections of three modern tapir species revealed that the m. infraspinatus originates from both supraspinous and infraspinous fossae for all species, lying on both sides of the distal scapular spine. The epimysial border between the m. supraspinatus and m. infraspinatus origin sites are marked in all species by an ossified ridge, sometimes extending the length of the scapular spine. This “supraspinous ridge” is clearly visible on the scapular surface of both modern and extinct Tapirus scapulae; however, the ridge does not appear present in any non‐ Tapirus tapiroids examined (e.g., Helaletes , Nexuotapirus ), nor in other perissodactyls or artiodactyls. Moreover, the ridge exhibits a clearly distinct morphology in Tapirus indicus compared to all other Tapirus species examined. Combined, these findings indicate that the presence and position of the “supraspinous ridge” may represent a robust phylogenetic character for reconstructing relationships within tapiroids. Unfortunately, any functional locomotor outcomes or benefits of the m. infraspinatus straddling the scapular spine remains elusive. This study represents a firm reminder for anatomists, veterinarians, and paleontologists to (where possible) look beyond veterinary model systems when inferring musculoskeletal form or function in non‐model organisms.
Language
English
Source (journal)
The anatomical record: advances in integrative anatomy and evolutionary biology. - New York, N.Y.
Publication
New York, N.Y. : 2023
ISSN
1932-8486 [print]
1932-8494 [online]
DOI
10.1002/AR.25352
Volume/pages
(2023) , p. 1-18
ISI
001104757900001
Pubmed ID
37966173
Full text (Publisher's DOI)
Full text (open access)
The author-created version that incorporates referee comments and is the accepted for publication version Available from 15.05.2024
Full text (publisher's version - intranet only)
UAntwerpen
Faculty/Department
Research group
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
Web of Science
Record
Identifier
Creation 29.11.2023
Last edited 10.01.2024
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