In all, the program detected 18 types of rhythm (the sequence of intervals between clicks), five types of tempo (the duration of the entire coda), three types of rubato (variations in duration), and two types of ornamentation — an “extra click” added at the end of a coda in a group of shorter codas.
These features could all be mixed and matched to form an “enormous repertoire” of phrases, the scientists reported in May. However, the approach has its limitations. While machine learning is adept at identifying patterns, it doesn’t shed light on the meaning.
A next step, according to the study, is interactive experimentation with whales, along with observations of whale behavior, which could be an important part of unraveling the syntax of sperm whale click sequences.