Sperm Whales Synchronize Complex Vocal Exchanges Beyond Single Clicks, Study Finds

A recent study led by Professor Roy Diamant at the University of Haifa, in collaboration with the international Project CETI team headed by Professor Dan Chernob, reveals that sperm whale (Physeter macrocephalus) communication is far more complex than previously understood. These large toothed whales, known for their deep diving capabilities and sophisticated sonar, communicate using rhythmic clicks called codas within their social groups.

The research, conducted in the Caribbean Sea near Dominica and published in the journal Bioacoustics, analyzed nearly 4,000 codas recorded via acoustic tags attached to identified whales. The team discovered that a sperm whale's vocalization is influenced not just by the immediately preceding click but by a sequence of up to ten prior codas from another whale. This indicates that their vocal exchanges rely on ongoing contextual sequences rather than isolated signals.

Key acoustic features such as coda duration, intervals between clicks, and timing before the next response were significant in predicting subsequent codas. The study also found synchronization between whales, with changes in one whale's click rate or duration often mirrored by the other. This suggests a coordinated vocal interaction resembling a structured social communication system, potentially akin to a language.

Professor Diamant emphasized that the findings shift the focus from decoding individual codas to understanding the order, dependency, and timing in whale vocal exchanges. The use of extensive acoustic datasets and artificial intelligence enabled the identification of these patterns, overcoming previous challenges in isolating communication between whale pairs.

This research advances the understanding of sperm whale social communication and opens new avenues for studying one of the most intriguing animal communication systems in the natural world.