Dolphins have memory of an elephant

Dolphins are able to recognise the signature calls of their own species even after being apart for 20 years, according to a study from the Proceedings B magazine.

The discovery reveals that the sea mammals’ recognition of their peers’ characteristic “whistle” may last longer than a human’s identification of a face. This is explained by the fact that the animal’s call barely changes while human features develop throughout the years.

The study was conducted with 43 captive dolphins from six different zoos and water parks which had switched animals throughout the years, and consisted of getting the dolphins to listen to the call of its fellow species. Results showed that the animals reacted to the familiar “whistles” of former tank mates that they had not been in contact with for years.

“As soon as they hear a dolphin they know, they come closer to the speaker, normally in a quick manner. Sometimes, they swim in circles and whistle back in an attempt to receive an answer,” said Jason Bruck, the researcher in charge of the study.

Bruck highlighted the curious tale of Bailey, a dolphin which recognised the call of old acquaintance Allie, a dolphin it had not interacted with for more than 20 years.