Dolphins call each other by name.

Each bottlenose dolphin develops its own 'signature whistle'. Others copy that whistle to call it, and dolphins respond when they hear their own. They seem to remember the whistles of old companions for decades.

Truth label: Established. Strong evidence and broad agreement among experts.

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Twenty years later

Dolphins separated for over 20 years still responded to a former companion's whistle.

Choosing a name

Calves develop their whistle in their first year, often shaped by sounds around them.

Learn

1. Rare in nature. Using learned names for individuals is very rare. Humans and dolphins are among the few.

Test yourself

Sources

• Signature whistle

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