Variability of Structural and Biomechanical Prameters of Pelophylax esculentus (Amphibia, Anura) Limb Bones

Abstract

Structural and biomechanical parameters of Edible Frog, Pelophylax esculentus (Linnaeus, 1758), limb bones, namely, mass, linear dimensions, parameters of the shaft ’s cross-sectional shape (cross-sectional area, moments of inertia, radiuses of inertia) were investigated. Some coeffi cients were also estimated: diameters ratio (df/ds), cross-sectional index (ik), principal moments of inertia ratio (Imax/Imin). Coeffi cients of variation of linear dimensions (11.9–20.0 %) and relative bone mass (22–35 %) were established. Moments of inertia of various bones are more variable (CV = 41.67–56.35 %) in relation to radii of inertia (CV = 9.68–14.67 %). Shaft ’s cross-sectional shape is invariable in all cases. However, there is high individual variability of structural and biomechanical parameters of P. esculentus limb bones. Variability of parameters was limited by the certain range. We suggest the presence of stable norm in bone structure. Stylopodium bones have the primary biomechanical function among the elements of limb skeleton, because their parameters most clearly responsive to changes in body mass.