Feeding and the Digestive System

Death by octopus (Macroctopus maorum): Laryngeal luxation and asphyxiation in an Indo‐Pacific bottlenose dolphin (Tursiops aduncus)

“…, Cozzi et al . ). The rostral tip of the larynx is permanently seated within the internal nares (choanae) by the palatopharyngeal sphincter muscle, therefore separating the respiratory and digestive tracts to a greater extent than in other mammals (Reidenberg and Laitman ; Pabst et al .…”

“…, Cozzi et al . ). Therefore, under normal circumstances, the respiratory and digestive tracts of odontocetes do not communicate, a useful adaptation for ingesting prey underwater; however, dolphins can voluntarily displace their larynx from the choanae in order to swallow large, bulky prey (Reidenberg and Laitman , Stolen et al .…”

“…As their esophagus is highly distensible, the limiting factor for prey size is the diameter of the dorsally communicating lateral channels of the pharynx, as well as that of the faucal isthmus (Cozzi et al . ). One study of stomach contents in Tursiops sp.…”

“…In terrestrial mammals, the epiglottis in its intranarial breathing position separates the respiratory and digestive tracts; as the animal swallows, the larynx rises and the epiglottis protects the entrance to the trachea so the food bolus is diverted into the esophagus (Pabst et al 1999). In odontocetes, the epiglottis and paired cuneiform processes of the arytenoid cartilages form, respectively, the ventral and dorsal elements of a rigid elongated arytenoepiglottic tube referred to as the "goosebeak" larynx (Reidenberg and Laitman 1987;Brzica et al 2015;Cozzi et al 2017a, b), centrally located between the wide lateral channels of the pharynx, which lead to the esophagus lying dorsally to the trachea (Pabst et al 1999, Cozzi et al 2017c). The rostral tip of the larynx is permanently seated within the internal nares (choanae) by the palatopharyngeal sphincter muscle, therefore separating the respiratory and digestive tracts to a greater extent than in other mammals (Reidenberg and Laitman 1987;Pabst et al 1999;Brzica et al 2015;Cozzi et al 2017a, b).…”

“…The rostral tip of the larynx is permanently seated within the internal nares (choanae) by the palatopharyngeal sphincter muscle, therefore separating the respiratory and digestive tracts to a greater extent than in other mammals (Reidenberg and Laitman 1987;Pabst et al 1999;Brzica et al 2015;Cozzi et al 2017a, b). The lateral channels of the pharynx communicate dorsally; food passes through them either side of the larynx when swallowed (Pabst et al 1999, Cozzi et al 2017c. Therefore, under normal circumstances, the respiratory and digestive tracts of odontocetes do not communicate, a useful adaptation for ingesting prey underwater; however, dolphins can voluntarily displace their larynx from the choanae in order to swallow large, bulky prey (Reidenberg and Laitman 1987, Stolen et al 2013, IJsseldijk et al 2015, Cozzi et al 2017a.…”