Neuroethology Chemosensory Control of Feeding Behavior in the Lobster. The feeding behavior of most organisms can be divided into an appetative phase where the animal first detects, searches and locates food and a consummatory phase there the actual consumption takes place. Both of these phases are under control of a variety of distance and contact chemoreceptors.
Lobsters are no exception and are provided with a rich variety of chemosensory structures.
The paired antennules are the equivalent of the nose of a lobster. These structures beat rhythmically to sample compounds in the water and are invested with a rich distribution of chemosensory sensillae. In addition, the walking legs are also covered with chemosensory sensillae as are the mouthparts, the maxillapeds and maxillae. For example, the antennules are thought to have the lowest behavioral threashold and their stimulation appears to trigger locomotion and investigative behavior. As the stimulus concentration increases, stimulation of the sensillae on the anterior walking legs triggers directed grasping movements, and finally stimulation of receptors on the maxillapeds are thought to trigger repetative chewing by the mandibles.