title: Letter: Comparative anatomy of the esophagus.
mesh_terms: D000818:Animals; D002415:Cats; D004285:Dogs; D004947:Esophagus / Q000033:anatomy & histology* / Q000502:physiology; D005769:Gastrointestinal Motility; D006168:Guinea Pigs; D006801:Humans; D008394:Marsupialia; D008954:Models, Biological; D009130:Muscle, Smooth / Q000033:anatomy & histology / Q000502:physiology; D009893:Opossums; D011817:Rabbits