In birds, the jaw musculature is a crucial adaptive feature involved in feeding. The morphological traits and postnatal growth patterns of jaw muscles constitute a useful proxy to interpret feeding function and ecology. This study aims to describe the jaw muscles of Rhea americana and explore their postnatal growth pattern. A total of 20 specimens of R. americana representing four ontogenetic stages were studied. Jaw muscles were described, weighed and their proportions with respect to body mass were calculated. Linear regression analysis was used to characterize ontogenetic scaling patterns. The morphological patterns of jaw muscles were characterized by their simplicity: bellies with few or no subdivisions and similar to those described for other flightless paleognathous birds. In all stages, the muscles pterygoideus lateralis, depressor mandibulae, and pseudotemporalis had the greatest mass values. The proportion of total jaw muscle mass decreased with age from 0.22% in 1-month-old chicks to 0.05% in adults. Linear regression analysis showed that all muscles scaled with negative allometry with respect to body mass. The progressive decrease of jaw muscle mass relative to body mass in adults could be related to the generation of less force, which is in accordance with the herbivorous diet of adults. In contrast, the diet of rhea chicks includes a large proportion of insects thus, this greater muscle proportion could be associated with the ability to generate more force, thus providing better abilities to grasp and hold more mobile prey.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/jmor.21596 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Progress and prospects in antisense oligonucleotide-mediated exon skipping therapies for Duchenne muscular dystrophy.
J Muscle Res Cell Motil
January 2025
Institute of Developmental and Regenerative Medicine, University of Oxford, IMS-Tetsuya Nakamura Building, Old Road Campus, Roosevelt Dr, Headington, Oxford, OX3 7TY, UK.
Recent years have seen enormous progress in the field of advanced therapeutics for the progressive muscle wasting disease Duchenne muscular dystrophy (DMD). In particular, four antisense oligonucleotide (ASO) therapies targeting various DMD-causing mutations have achieved FDA approval, marking major milestones in the treatment of this disease. These compounds are designed to induce alternative splicing events that restore the translation reading frame of the dystrophin gene, leading to the generation of internally-deleted, but mostly functional, pseudodystrophin proteins with the potential to compensate for the genetic loss of dystrophin.
View Article and Find Full Text PDFComment on "Near-Normalized Maxillomandibular Relationship and Upper Airway in Infants With Robin Sequence Treated With Stanford Orthodontic Airway Plate".
Cleft Palate Craniofac J
January 2025
Sleep Medicine, Stanford University, Stanford, CA, USA.
It's interesting to note that despite clinical improvements in upper airway dimensions, the maxillary, mandibular, and mandibular body lengths remained smaller than those of controls. This finding may represent an underlying neurocristopathy, which represents a deficiency in the population of neural crest cells available in the embryonic maxillary and mandibular processes de novo. Indeed, it is known that craniofacial dimensions in infants with malformations, such as cleft palate, are often smaller when compared to non-cleft counterparts.
View Article and Find Full Text PDFBackground: Although varieties in chewing patterns are essential for the transformation of food in mouth and thereby its sensorial perception, there are few reports that show the effect of chewing frequency on food oral processing and its properties.
Objective: The current study tested whether consciously controlled chewing frequency influences the oral processing of habitually consumed foods and their sensory analysis.
Method: Chewing behaviour was analysed during the mastication of mushed potato samples by 20 participants in two separate test sessions, in which they were instructed to chew the sample in their habitual manner (free chewing test) or follow a preprogrammed video animation displayed on a screen, wich guided them to maintain a constant chewing frequency (F-const chewing test).
Prevalence and risks of sleep bruxism in children and adolescents presenting for orthodontic treatment.
Eur J Orthod
December 2024
Department of Orthodontics, School of Dental Medicine, University at Buffalo, 3435 Main Street, Buffalo, NY 14214, United States.
Objectives: This study determined the prevalence and risks of definite sleep bruxism (SB) among children and adolescents presenting for orthodontic treatment.
Methods: This was a cross-sectional study of 7-16-year-old subjects pursuing orthodontic treatment for the first time. The presence or absence of SB was determined using an overnight mandibular movement monitoring inertial measurement sensor, worn by each participant for two consecutive nights.
Assessment of the role of coronoid in restrictive jaw disorders and physiologic mandibular movements.
Natl J Maxillofac Surg
November 2024
Department of Oral and Maxillofacial Surgery, Lucknow, Uttar Pradesh, India.
Introduction: Restricted mouth opening has major health implications, such as malnutrition, difficulty in speech, and poor oral hygiene resulting in a functional shortage of the masticatory system. Reduced mouth opening can occur due to trismus, as in the oral submucous fibrosis (OSMF) condition. Excision of fibrous bands in OSMF leads to reestablishment of the mouth opening.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!