Ontogenetic scaling of pelvic limb muscles, tendons and locomotor economy in the ostrich (<i>Struthio camelus</i>)

Channon, Sarah B, Young, Iain S ORCID: 0000-0002-9502-6216, Cordner, Beckie and Swann, Nicola (2019) Ontogenetic scaling of pelvic limb muscles, tendons and locomotor economy in the ostrich (<i>Struthio camelus</i>). JOURNAL OF EXPERIMENTAL BIOLOGY, 222 (17). jeb182741-.

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Abstract

In rapidly growing animals there are numerous selective pressures and developmental constraints underpinning the ontogenetic development of muscle-tendon morphology and mechanical properties. Muscle force generating capacity, tendon stiffness, elastic energy storage capacity and efficiency were calculated from muscle and tendon morphological parameters and <i>in vitro</i> tendon mechanical properties obtained from a growth series of ostrich cadavers. Ontogenetic scaling relationships were established using reduced major axis regression analysis. Ostrich pelvic limb muscle mass and cross-sectional area broadly scaled with positive allometry, indicating maintained or relatively greater capacity for maximum isometric force generation in larger animals. The length of distal limb tendons was found to scale with positive allometry in several tendons associated with antigravity support and elastic energy storage during locomotion. Distal limb tendon stiffness scaled with negative allometry with respect to body mass, with tendons being relatively more compliant in larger birds. Tendon material properties also appeared to be size-dependent, suggesting that the relative increased compliance of tendons in larger ostriches is due in part to compensatory distortions in tendon material properties during maturation and development, not simply from ontogenetic changes in tendon geometry. Our results suggest that the previously reported increase in locomotor economy through ontogeny in the ostrich is due to greater potential for elastic energy storage with increasing body size. In fact, the rate of this increase may be somewhat greater than the conservative predictions of previous studies, thus illustrating the biological importance of elastic tendon structures in adult ostriches.

Item Type:	Article
Uncontrolled Keywords:	Growth, Ontogeny, Allometry, Biped, Economical locomotion, Locomotor efficiency
Depositing User:	Symplectic Admin
Date Deposited:	19 Aug 2019 08:27
Last Modified:	24 Jan 2024 23:55
DOI:	10.1242/jeb.182741
Related URLs:	Author Publisher
URI:	https://livrepository.liverpool.ac.uk/id/eprint/3051962

Available Versions of this Item

• Ontogenetic scaling of pelvic limb muscles, tendons and locomotor economy in the Ostrich (Struthio camelus). (deposited 29 Jul 2019 09:19)
  • Ontogenetic scaling of pelvic limb muscles, tendons and locomotor economy in the ostrich (<i>Struthio camelus</i>). (deposited 19 Aug 2019 08:27) [Currently Displayed]