Possible phylogenetic relationships based on the morphology of the ovine calcaneal bone (Ovis aries Linnaeus, 1758)

Abstract

In sheep, there is a relationship between the mass of the crural muscles and the greater or lesser ability to walk, in turn perhaps related to body proportions, so there could be functional differences between breeds, based on different motor skills. The calcaneal bone represents the base of insertion of the crural muscles responsible in part for walking. To corroborate this hypothesis, digital images of 28 calcanei of domestic sheep of four breeds from the Iberian Peninsula were obtained: Churra, Merina, Merino preto and Merino branca. The images were analysed using geometric morphometry techniques from 20 anatomical landmarks (bone points). Significant differences were obtained between breeds, both for shape and size, being greater in merinos. It can be deduced that the conformation of the calcaneus reflects the variable enthesis area according to the greater or lesser development of the crural muscles. It is considered that these differences between races are mainly defined as a matter of body conformation rather than dynamogenic capacity.