Researchers have observed male Amazon river dolphins engaging in an unusual behavior known as 'aerial urination,' where they flip onto their backs and release jets of urine into the air. The behavior appears to serve a social or communicative purpose among these aquatic mammals. Scientists suggest that the bristles on the dolphins' snouts act as chemical sensors, helping them decode messages in other dolphins' urine. This behavior may play a role in their social interactions and serve as a form of communication.