Planarians exhibit traits of cephalization but are unique among bilaterians in that they ingest food by means of goal-directed movements of a trunk-positioned pharynx, following protrusion of the pharynx out of the body, raising the question of how planarians control such a complex set of body movements for achieving robust feeding. Here, we use the freshwater planarian Dugesia japonica to show that an isolated pharynx amputated from the planarian body self-directedly executes its entire sequence of feeding functions: food sensing, approach, decisions about ingestion, and intake. Gene-specific silencing experiments by RNA interference demonstrated that the pharyngeal nervous system (PhNS) is required not only for feeding functions of the pharynx itself but also for food-localization movements of individual animals, presumably via communication with the brain. These findings reveal an unexpected central role of the PhNS in the linkage between unique morphological phenotypes and feeding behavior in planarians.

扁嘴虫具有头颅化的特征，但在双侧扁鲨中是独特的，因为它们会通过咽部伸出身体后，通过躯干定位的咽部的目标定向运动来摄取食物，从而引发了涡虫如何控制这种复杂的集合的问题。的身体运动以实现强劲的进食。在这里，我们使用淡水涡planar证明从planar虫体内切除的孤立咽部会自动执行其整个喂食功能序列：食物感应，进食方式，摄入决定和摄入。通过RNA干扰进行的基因特异性沉默实验表明，咽神经系统（PhNS）不仅需要咽部自身的进食功能，而且还需要个别动物的食物定位运动（大概是通过与大脑的交流）。这些发现揭示了PhNS在独特的形态表型和饲喂动物的进食行为之间的联系中出乎意料的核心作用。