“…Sirenians are generally slow‐moving animals with a low metabolic rate (Gallivan and Best, ), unlike cetaceans, which are normally highly active and fast‐moving, with mammaries located below the surface of the skin to help minimize water resistance during swimming (Pabst et al, ). Perhaps such streamlining is not so important for the sirenians, given that they are the only aquatic mammals with axillary mammaries; but more likely, the morphology and location of sirenian mammaries are pleisomorphic (De Jong and Zweers, ; Pabst et al, ), rather than an aquatic adaptation, as their closest living relatives, elephants, also have one pair of axillary mammaries (Miall and Greenwood, ; Laursen and Bekoff, ).…”