Embryonic development and cranial ossification of the Japanese Aodaishō, Elaphe climacophora (Serpentes: Colubridae): with special reference to the prootic bone and auditory evolution in snakes.
cranial ossification
embryonic staging
heterochrony
prootic
snake
Journal
Anatomical record (Hoboken, N.J. : 2007)
ISSN: 1932-8494
Titre abrégé: Anat Rec (Hoboken)
Pays: United States
ID NLM: 101292775
Informations de publication
Date de publication:
11 Jul 2024
11 Jul 2024
Historique:
revised:
24
06
2024
received:
14
04
2024
accepted:
27
06
2024
medline:
12
7
2024
pubmed:
12
7
2024
entrez:
12
7
2024
Statut:
aheadofprint
Résumé
Snakes show remarkably deviated "body plan" from other squamate reptiles. In addition to limb loss, they have accomplished enormous anatomical specialization of the skull associated with the pit organs and the reduction of the tympanic membranes and auditory canals in the outer ears. Despite being the most diverse group of snakes, our knowledge of the embryonic staging for organogenesis and cranial ossification has been minimal for Colubridae. Therefore, in the present observation, we provide the first embryonic description of the Japanese rat snake Elaphe climacophora. We based our study on the Standard Event System (SES) for external anatomical characters and on a description of the cranial ossification during post-ovipositional development. We further estimated the relative ossification timing of each cranial bony element and compared it with that of selected other snakes, lizards, turtles, and crocodilians. The present study shows that the relative ossification timing of the palatine and pterygoid bones is relatively early in squamates when compared to other reptiles, implying the developmental integration as the palate-pterygoid complex in this clade and functional demands for the unique feeding adaptation to swallow large prey with the help of their large palatine and pterygoid teeth. Furthermore, unlike in species with pit organs, the prootic bone of Ela. climacophora is expanded to provide articulation with the supratemporal, thereby contributing to the hearing system by detecting substrate vibration. We also demonstrate that the relative timing of the prootic ossification is significantly accelerated in colubrids compared to snakes with pit organs. Our finding suggests that the temporal changes of the prootic ossification underpin the evolution of the perception of the ground-bourne sound signals among snakes.
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Subventions
Organisme : Japan Society for the Promotion of Science (JSPS)
ID : 22J00127
Organisme : Japan Society for the Promotion of Science (JSPS)
ID : 23K14255
Organisme : Japan Society for the Promotion of Science (JSPS)
ID : 22K06337
Organisme : Japan Society for the Promotion of Science (JSPS)
ID : JSPS 22K06786
Organisme : Deutsche Forschungsgemeinschaft (DFG)
ID : WE-5440/6-1
Informations de copyright
© 2024 American Association for Anatomy.
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