Drifting along ocean currents in their mother’s shadow, newborn bottlenose dolphins sing to themselves. They create a unique siren of squeaks, known as a signature whistle, which scientists have likened to a human name.
Unlike most animals, dolphins cannot use voices as their identifying feature because it becomes distorted at different depths. They instead invent a melody – a pattern of sound frequencies held for specific lengths of time – that they use to identify themselves for the rest of their lives. Bottlenose dolphins (Tursiops truncatus) can even imitate the whistles of their friends, calling out their names if they are lost. Additional information, such as reproductive status, can be conveyed by changing the volume of different parts of the whistle, not unlike how people emphasize certain words to add nuance.
But how do dolphins decide what to call themselves?
