Aunt (Kate 1) and niece(Tess 2) displaying greeting behavior.

Greeting rumbles:
One of the most striking forms of elephant vocal communication occurs when family groups come together and burst into a chorus of greeting rumbles. Recent work has shown that elephants are able to distinguish familiar from unfamiliar voices, confirming the long-held hunch that greeting rumbles involve recognition of another individual or family.

The illustration below is a sound spectrogram of greeting rumbles exchanged between two African forest elephants in the summer of 2000 at a mineral-rich forest clearing in the Dzanga National Park, Central African Republic. The photo above shows the elephants as they made these calls. Both adult females, Kate 1 and Tess 2, displayed stereotypical greeting behavior including ear flapping, standing side by side, and alternating calls.

To hear the recording, click on the spectrogram below.. Each rumble appears as a crescent-shape in the spectrogram. Because the elephants were very close to the microphone, many harmonics are visible at multiples of the lowest frequency. The rumbles overlap in several places, as is typical of elephant greetings. (When you play the sound, you may also hear the whispers of the Elephant Listening Project team, "It's a greeting".) More about spectrograms>>