Two adult elephants play at fighting. Elephants are highly sociable animals, with all but the itinerant adult males living in tightly knit groups, so it is not surprising that they have evolved many ways to communicate with one another. Elephants also use chemical cues to detect coded messages. For example, males and females sniff at each other's urine to see whether the other is receptive to mating.
Some elephants rub the resulting discharge on tree trunks, perhaps to leave messages behind.
And of course, elephants can be quite vocal. The research of Moss and her colleagues shows that the animals have at least 25 distinctive calls. Most familiar is the bellowing trumpet, which indicates high excitement. Much less obvious are an elephant's soft rumbles, some of which humans can barely hear. These rumbles can communicate dozens of different messages.