Research carried out in the Marine Biology and Biotechnology program at BGU's Eilat Campus have shown amazing evidence: Dolphins imitate a unique sound that is in effect the 'name' of another dolphin, even after the dolphin has left the reef or died – proof that animals are capable of expressing a profound memory, researchers say. This is the first time that animals have been documented "remembering" another animal. The research findings were first published in Alef, Bet, Gimmel, BGU's Hebrew language magazine and later presented at a scientific conference.
At Eilat's Dolphin Reef, there is a dolphin pod in the same area where holidaymakers visit. The dolphins make contact with whom they choose. It's no wonder that the Reef attracts not only holidaymakers, but also researchers who want to understand these special creatures, who are highly gifted both with intelligence and emotionally, who live in pods and manage complex social lives.
Tan Morgan – a doctoral student from Scotland who is studying marine biology at BGU – came to Eilat to research dolphins at BGU's lab in Eilat. After completing a bachelor's degree at Cambridge University in England, during which she was exposed to voices made by animals, she was excited to hear of an opportunity to research dolphin voices in Eilat.
An experiment that she carried out was based on recordings of dolphin sounds in different areas of the Reef at different times. The original purpose of the study – conducted under the auspices of marine biologist Prof. Nadav Shashar, was to examine whether there is a difference between the sounds created by the dolphins in different situations related to the activities of humans. The recordings were analyzed and classified by means of an advanced program.
During the research, Morgan was surprised to find a number of signature whistles that did not seem logical. Dolphins emit unique sounds, or vocal signatures, that other dolphins in the pod can use to identify them. They call each other using this unique signature whistle. During the first year of their lives the dolphins learn how to make a lot of different sounds, they imitate some of the other dolphins, some invent their own, and finally they create a whistle that is unique to them, which no other dolphin uses. The moment it develops the whistle, that's its name, its signature whistle. The signature whistles of the dolphins at the Reef are documented in International Laboratory for Dolphin Behavior Research in Eilat which was established in 1994.
The unexpected result was that when Morgan analyzed the recordings, she was surprised to discover the signature whistles of three dolphins that no longer live in the reef. One of them, a dolphin named Dicky, was returned to the Black Sea in 1998; the other two, Dana and Shai, died in 2013 and 2015, respectively. At first, she didn't believe it and thought that maybe it was a mistake. An in-depth examination of the audio files revealed that Morgan was not mistaken, and that the dolphins being studied repeated the signature whistle of their friends, who are no longer with them.
The importance of the research is that for the first time it presents empirical proof that an animal is capable of remembering other members of its species even when they are no longer alive.
