Fig. 4

Anatomical details of mouth and lips: a Asian elephant skull in frontal view and b view into the oral cavity from below the maxilla. c, d Mouth opened on command in c m, 7 years and d f, 35 years. e, f Mouth closing and opening while feeding (f, 45 years), e tongue visible in the middle and upper lips above labial angles and f mouth fully closed, note the two sides of the lower lip slightly overlapping while the tip of the lip hangs loosely, images from Video S2. g Frontal view of closed mouth, trunk lifted during social interaction (f, 42 years)