Comparative Study of Tongue and Lingual Papillae in Four Species of Birds: Otis tarda, Nycticorax nycticorax, Chrysolophus pictus and Corvus macrorhynchos

This study examined tongue morphology in four birds (Otis tarda, Nycticorax nycticorax, Chrysolophus pictus, and Corvus macrorhynchos) using light and scanning electron microscopy technique.Species-specific variations included mucosal features, papillae patterns, and specialized structures.Corvus macrorhynchos showed a bifid tongue tip, marginal filiform papillae, and a symmetrical median groove, with distinct epithelial cell margins.Nycticorax nycticorax had clustered filiform papillae and a continuous median sulcus.Lingual gland openings occurred in both body and root regions of Otis tarda and Corvus macrorhynchos but only at the root in Nycticorax nycticorax, while absent in Chrysolophus pictus.Histology revealed shared components: keratinized tips, entoglossal cartilage, mucus glands, and root conical papillae.Nycticorax nycticorax and Chrysolophus pictus uniquely displayed elastic fibers around root blood vessels.All species exhibited posterior-oriented marginal conical papillae, with conserved lamina propria organization despite papillae variations.These differences reflect ecological adaptations.Corvus macrorhynchos' bifid tip and Nycticorax nycticorax's clustered papillae suggest dietary specialization, underscoring how avian tongue morphology aligns with environmental niches.