Observation of mandibular yaw movement in the Sulawesi babirusa (Babyrousa celebensis).

Recent observations of babirusa skulls have found there are two types of wear patterns on the molar teeth, suggesting a relationship with the grinding of their specific diet in the wild. Yaw rotation, which is involved in the transverse grinding of food particles, has not been reported for the babirusa mandible. Therefore, we have sought a simple protocol to geometrically describe such a motion based on videos of a male babirusa. When observed in frontal view, the yaw movement of the babirusa mandible could be shown as a waveform with approximately three cycles per second on the positiontime graph based on the measured xcoordinates of the mandibular canines. [ABSTRACT FROM AUTHOR]