Type
Text
Type
Dissertation
Advisor
Fleagle, John G | Jungers, William | Stern, Jr., Jack | Taylor, Andrea | Wall, Christine.
Date
2013-12-01
Keywords
Epaxial muscles, Fiber types, Muscle physiology, Spinal mobility | Morphology
Department
Department of Anthropology.
Language
en_US
Source
This work is sponsored by the Stony Brook University Graduate School in compliance with the requirements for completion of degree.
Identifier
http://hdl.handle.net/11401/76922
Publisher
The Graduate School, Stony Brook University: Stony Brook, NY.
Format
application/pdf
Abstract
The spine is the central element of the locomotor skeleton, acting as a link between the head and limbs. However, despite well-documented differences in spinal morphology among primates, we have comparatively little quantitative documentation on the structural characteristics of muscles that move the spine. The primary goals of this investigation were: (i) to identify and characterize morphological and related physiological, histological, and mechanical aspects of selected epaxial muscles in two groups of related but behaviorally distinct primates; and (ii) to investigate if these features could be interpreted in terms of the degree of spinal mobility during locomotion. To these ends, thoracic and lumbar segments of three epaxial muscles (iliocostalis, longissimus, and multifidus) were examined for physiological and histological differences in two pairs of primates: (a) Galago senegalensis vs Nycticebus coucang, and (b) Chlorocebus aethiops vs. Erythrocebus patas. In pair (a), G. senegalensis are habitual leapers, while N. coucang are cautious arboreal quadrupeds. In pair (b), E. patas are terrestrial quadrupeds; while C. aethiops engage in both terrestrial and arboreal quadrupedalism. Physiological and histological parameters studied were: (i) muscle mass, (ii) angle of pinnation, (iii) fiber length, (iv) tendon length, (v) potential excursion of muscle (h), (v) physiological cross-sectional area (PCSA), and (vi) fiber type. Mechanical differences in muscles were studied by investigating characteristics of bony lever arm of lumbar vertebrae of each species. The results indicate that within the first pair, epaxial muscles of the leaper (G. senegalensis) are physiologically and histologically designed for generating high contraction velocity (important for rapid back extension during leaping); while the muscles of the slow-moving N. coucang are adapted for postural and stabilizing purposes. Differences in bony lever arm also support these observations. Within the second pair, muscles of C. aethiops are physiologically suited for generating higher force relative to those of E. patas. Histologically and mechanically, however, muscles of C. aethiops are adapted for producing high contraction velocity (relative to those of E. patas) required for rapid back extension. These differences can possibly be explained by differences in the respective positional behaviors of the two monkeys. In sum, these results indicate that differences in spinal mobility pattern are reflected in structural characteristics of epaxial muscles. Future work will focus on more fine-grained analyses of the locomotor role of spine in primates, including in vivo muscle recruitment patterns. | 420 pages
Recommended Citation
Huq, Md Emranul, "Physiological, Histological, and Mechanical Characteristics of Selected Epaxial Muscles in Primates" (2013). Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions). 2795.
https://commons.library.stonybrook.edu/stony-brook-theses-and-dissertations-collection/2795