Dolphins Have The Longest Memories In The Animal Kingdom

Move over elephants, it would seem the dolphin has the best memory in the animal kingdom according to the latest research. New experiments suggest the bottlenose dolphin has the ability to remember the whistles of other dolphins they have encountered or lived with even after they have been separated for over 20 years. Each dolphin is identified by a unique whistle which acts just like a name, enabling these marine mammals to maintain strong social bonds.

Remembered by a dog

This new research has conclusively found that dolphins have the longest memory of any species of animals apart from humans. Chimpanzees and elephants also present with similar memory abilities though these have yet to be tested according to Dr. Jason Bruck of the University of Chicago. Dr. Bruck had the idea to study the memory of animals when he was remembered and greeted by his brother’s dog after a four year absence.

Lots of data on dolphins

Dr. Bruck decided to study dolphin behaviour because they have extremely tight social bonds which are very important and there are excellent records for captive dolphins (rather than wild dolphins). He collected data from six facilities and 43 bottlenose dolphins throughout the U.S. and Bermuda. These facilities formed a breeding consortium that have been swapping dolphins for decades and kept meticulous records of each dolphin’s social partners.

Dolphins remember their companions

Dr. Bruck began by playing recordings of a number of unfamiliar whistles to the dolphins that were participating in the study. The dolphins eventually got bored and stopped checking out the underwater speaker that was making the sounds. At that point Dr. Bruck started to play the sounds of dolphins the subjects of the study were familiar with. When the dolphins heard these sounds they would perk up and approach the speakers, and in most cases they would whistle their own name in the hope of a response. In general the dolphins under study tended to respond more to the sounds of animals they had known decades ago than to animals that were picked randomly, which suggests they did indeed recognise their previous companions.

Memory Linked to Smarts?

It is still not known why a dolphin with a lifespan in the wild of 20 years would need long term memory. Some people theorise that it may be due to having to maintain relationships because over time, groups of dolphins tend to break up and reorganise themselves into new alliances. This type of social system is known as “fission-fusion” and is also seen in both chimpanzees and elephants which are also both social and highly intelligent species.

5 dolphins_Save_these_beautiful_creatures by Jay Ebberly, on Flickr