YGA Journal | Article
World Whale & Dolphin Day
Echoes Underwater: The Remarkable Communication System of Whales and Dolphins
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Article
Published July 23, 2023
Whales and dolphins, collectively known as cetaceans, are some of the most socially complex and intelligent beings on our planet. At the core of their social intelligence lies a remarkable communication system that is truly an acoustic marvel. This article delves into the intricacies of their communication, shedding light on what we have learned so far and what remains a mystery.
The Language of Dolphins
Dolphins are renowned for their intricate system of vocal communication, deploying a symphony of clicks and whistles to interact with each other. Each dolphin possesses a unique whistle, known as a signature whistle, which is akin to a human name. These signature whistles are formulated during a dolphin’s infancy and remain relatively constant throughout their lives. According to a study by Janik, Sayigh, and Wells (2006), dolphins use these signature whistles to recognize individual members within their pods, thus helping to maintain social cohesion (1).
Interestingly, dolphins don’t merely recognize these signature whistles; they also demonstrate an impressive ability to reproduce them, even altering the characteristics of their whistle to mimic those of another dolphin’s whistle. This extraordinary skill goes beyond a simple echo or mimicry, though. Dolphins will often use these mimicked whistles when the individual they are copying is not present, indicating that these vocalizations serve as a form of reference (2).
Moreover, dolphins’ communication extends beyond their species, as they have been observed reacting to human-made whistle sounds or imitating human speech patterns, showcasing an impressive degree of cross-species communication (3).
Dolphins also use echolocation for both navigation and hunting. By emitting a series of high-frequency clicks, dolphins can interpret the returning echoes to determine the location, size, and shape of objects in their environment, enabling them to find food or navigate murky waters with incredible precision (4).
Vocal Learning in Dolphins
Furthermore, dolphins are capable of mimicking the calls of others, a skill that may play a role in their social interactions. This vocal learning ability, previously thought to be limited to humans and some birds, underscores the complexity of dolphin communication.
Songs of the Whales
Whale songs are one of the most evocative and haunting sounds in the natural world, demonstrating a surprising level of complexity and cultural transmission. The most renowned vocalists of the cetacean family are the humpback whales. They deliver a symphony of sounds that comprise intricate patterns of moans, cries, clicks, and howls, producing what are referred to as songs.
The structure of these songs is highly organized and follows a specific pattern. Each song consists of a series of themes, each composed of phrases, and each phrase is made up of individual units or notes. Remarkably, all males within a population will sing the same version of the song, which can last anywhere from a few minutes to over twenty minutes. After completing the song, the male will often repeat it, sometimes for hours on end (1).
But humpback whale songs are not static. They undergo a process of gradual change or “cultural evolution,” with new song elements being added, modified, or discarded over time. This phenomenon was demonstrated in a 2000 study by Noad and colleagues, where song changes were tracked over several years (2).
Moreover, new songs can rapidly spread among populations. A remarkable study by Garland and colleagues (2011) showed that a new song can travel eastward across the Pacific, from Australia to French Polynesia, in just a couple of years, replacing the existing song of each population along its path. This rapid and widespread song change is believed to be the first example of a cultural phenomenon spreading in non-human populations (3).
While the exact function of these songs is still a topic of research, prevailing theories suggest they play a role in mating. Males might be using songs to demonstrate their fitness to females or to out-compete other males. However, the complexity and variability of these songs hint at a depth of function that we are only beginning to understand (4).
The exploration of whale songs illustrates the remarkable cognitive abilities and cultural richness of these marine giants. Further research promises to illuminate not just how they communicate but perhaps even why their songs hold such sway over us, echoing in our minds long after the last note has faded away.
Unsolved Mysteries of Whale Songs
Moreover, the function of these whale songs is not entirely understood. They are believed to play a role in mating displays but might also serve other purposes.
Conclusion
References
1. Janik, V.M., Sayigh, L.S., & Wells, R.S. (2006). Signature whistle shape conveys identity information to bottlenose dolphins. Proceedings of the National Academy of Sciences, 103(21), 8293-8297. doi: 10.1073/pnas.0509918103
2. King, S.L., & Janik, V.M. (2013). Bottlenose dolphins can use learned vocal labels to address each other. Proceedings of the National Academy of Sciences, 110(32), 13216-13221. doi: 10.1073/pnas.1304459110
3. Cholewiak, D., Cerchio, S., Jacobsen, J.K., Urbán, J.R., & Clark, C.W. (2018). Songbird dynamics under the sea: acoustic interactions between humpback whales suggest song mediates male interactions. Royal Society Open Science, 5(3), 171298. doi: 10.1098/rsos.171298
4. Noad, M.J., Cato, D.H., Bryden, M.M., Jenner, M., & Jenner, K.C.S. (2000). Cultural revolution in whale songs. Nature, 408(6812), 537. doi:10.1038/35046199
5. Tyack, P.L. (2000). Functional aspects of cetacean communication. In J. Mann, R.C. Connor, P.L. Tyack, & H. Whitehead (Eds.), Cetacean Societies: Field Studies of Dolphins and Whales (pp. 270-307). The University of Chicago Press.