This study sugests whale vocalisations (codas) have a significantly greater information capacity than was previously known. Prior work identified 21 discrete coda types, and the system could be understood to have an information rate of at most 5 bits/coda. However, our analysis suggests that with 18 rhythms, 5 tempos, optional ornamentation, and three variations (increasing, decreasing or constant duration) in rubato, the information rate could be up to twice as large .
MIT and CETI analyzed recordings of 8,719 codas from around 60 whales collected by the Dominica Sperm Whale Project between 2005 and 2018, using a mix of algorithms for pattern recognition and classification. They found that the way the whales communicate was not random or simplistic, but structured depending on the context of their conversations. This allowed them to identify distinct vocalizations that hadn’t been previously picked up on.