Listening to whale chit-chat

Scientists think they have new insights into the different dialects used by groups of sperm whales.

These great beasts live in very tight social groups, chatting amongst each other using a system of clicks.

The researchers have shown how separate clans - perhaps numbering thousands of animals - will use their own particular subtle sequence of noises.

Maurício Cantor and Hal Whitehead from Dalhousie University discuss their work.