Document Detail

Microanatomy of the mandibular symphysis in lizards: patterns in fiber orientation and Meckel's cartilage and their significance in cranial evolution.
MedLine Citation:
PMID:  20665813     Owner:  NLM     Status:  MEDLINE    
Although the mandibular symphysis is a functionally and evolutionarily important feature of the vertebrate skull, little is known about the soft-tissue morphology of the joint in squamate reptiles. Lizards evolved a diversity of skull shapes and feeding behaviors, thus it is expected that the morphology of the symphysis will correspond with functional patterns. Here, we present new histological data illustrating the morphology of the joint in a number of taxa including iguanians, geckos, scincomorphs, lacertoids, and anguimorphs. The symphyses of all taxa exhibit dorsal and ventral fibrous portions of the joints that possess an array of parallel and woven collagen fibers. The middle and ventral portions of the joints are complemented by contributions of Meckel's cartilage. Kinetic taxa have more loosely built symphyses with large domains of parallel-oriented fibers whereas hard biting and akinetic taxa have symphyses primarily composed of dense, woven fibers. Whereas most taxa maintain unfused Meckel's cartilages, iguanians, and geckos independently evolved fused Meckel's cartilages; however, the joint's morphologies suggest different developmental mechanisms. Fused Meckel's cartilages may be associated with the apomorphic lingual behaviors exhibited by iguanians (tongue translation) and geckos (drinking). These morphological data shed new light on the functional, developmental, and evolutionary patterns displayed by the heads of lizards.
Casey M Holliday; Nicholas M Gardner; Sylvia M Paesani; Mallory Douthitt; Jack L Ratliff
Related Documents :
10400223 - Mechanical sensitization of cutaneous c-fiber nociceptors by prostaglandin e2 in the rat.
19151953 - Photomultiplier tubes in biosensors.
22468633 - Conditioned [corrected] stimulus informativeness governs conditioned stimulus-unconditi...
Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, Non-P.H.S.    
Journal Detail:
Title:  Anatomical record (Hoboken, N.J. : 2007)     Volume:  293     ISSN:  1932-8494     ISO Abbreviation:  Anat Rec (Hoboken)     Publication Date:  2010 Aug 
Date Detail:
Created Date:  2010-07-28     Completed Date:  2010-10-13     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  101292775     Medline TA:  Anat Rec (Hoboken)     Country:  United States    
Other Details:
Languages:  eng     Pagination:  1350-9     Citation Subset:  IM    
Copyright Information:
(c) 2010 Wiley-Liss, Inc.
Program in Integrative Anatomy, Department of Pathology and Anatomical Sciences, University of Missouri Medical School, Columbia, Missouri 65212, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Cartilage / anatomy & histology*
Iguanas / anatomy & histology
Joints / anatomy & histology*
Lizards / anatomy & histology*
Mandible / anatomy & histology*
Skull / anatomy & histology*

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Hyperostosis frontalis interna and androgen suppression.
Next Document:  Reconstructions of the axial muscle insertions in the occipital region of dinosaurs: evaluations of ...