Metric variation in the postcranial skeleton of ostriches, <i>Struthio</i> (Aves: Palaeognathae), with new data on extinct subspecies

Abstract As a result of numerous fossil and subfossil finds ostriches, there is great demand for comprehensive osteometric dataset the living species subspecies genus Struthio. We meet this by providing set &amp;gt; 100 measurements sample 18 sexed skeletons, including all recently extinct ostriches. provide first mensural data two subspecies, hitherto questioned Struthio camelus spatzi from north-western Africa Arabian ostrich, syriacus. The unique skeletal proportions S. c. spatzi, with relatively short wing, broad pelvis, tarsometatarsus big third toe, confirm validity taxon suggest an increased stability at expense cursoriality, which might have contributed to its extermination humans. Our biometric analysis entire suggests subtle sexual dimorphism in ostrich skeleton, females having more robust limb bones (especially wider and/or deeper ends) despite being on average smaller than males. If confirmed further research, size-independent reflect independent regulation longitudinal transverse dimensions as revealed several studies morphological integration (covariance among traits) avian skeleton.