Dolphins have 'longest social memory'

[Still Waters]

Forget about elephants - scientists say that dolphins have the longest memories yet found in a non-human species.

Researchers in the US say that even after 20 years of separation, dolphins could recall the whistles of former companions.

The authors believe that these long-term memories are a product of the complex social connections that dolphins have evolved.

http://www.bbc.co.uk...onment-23589041