In case you still doubted that dolphins have an awareness rivaling our own, new research shows that these cetaceans can remember the whistles of their old tank-mates after being separated for more than 20 years! No species other than humans has demonstrated such a long-term social memory.
In bottlenose dolphin communication, there are normal whistles, and then there are signature whistles. Every dolphin develops its own unique signature whistle, which functions sort of like a name. So when a dolphin comes into contact with another pod in the wild, for example, it will use its signature whistle as a way of announcing its identity. Recent research has also shown that bottlenose dolphins will call each other by their signature whistles, similar to the way we address each other by name.