Some correlates of cranial and cervical morphology with predatory modes in snakes

Dissection of the cervical and basicranial regions in three species of snakes indicates that compared to Crotalus viridis and Lichanura roseofusca, Masticophis flagellum possesses relatively high numbers of compound axial muscle insertions on the atlas-axis and vertebrae numbers 3-5. It is suggested that the condition in Masticophis facilitates its vertical-neck-horizontal-head foraging posture and has allowed axial muscles inserting on the dorsocaudal braincase in this snake to generate vertical and lateral head movements more effectively.