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It’s no secret that orca are highly intelligent and social animals. This is something they flaunt openly to anyone who takes the time to observe them. With brains four times the size of ours and packed with more complex neural networks than what is common across the animal kingdom, you’d expect something interesting to be going on in there.1 But apart from it’s immense size, there are other characteristics of the orca’s brain which contribute to their particular kind of intelligence. The areas of the brain responsible for emotional thought and response are proportionally larger in orca than in any other animal. What’s more, contained in the orca brain is an extra lobe of tissue, absent even in humans, which functions as an extension of the parts of the brain associated with communication and social emotions.1 Orca therefore possess an emotional and social intelligence that rivals and perhaps even surpasses, in some ways, that of humans. They know love, happiness, sadness and more in a way that is unique to them.
How orca use their brainpower is best demonstrated through the way they communicate with each other. From general social interactions, mating, navigation and hunting to mother-calf teaching, orca have a whole lot to talk about and they’ve evolved some clever adaptations to facilitate this. Orca, like other toothed cetaceans, produce three kinds of sound: echolocation clicks, burst-pulse sounds, and whistles. Burst-pulse sounds and whistles are the most commonly used modes of communication for socialisation.2 Burst-pulse sounds are a series of rapidly repeated pulses produced using specialised folds of skin in the blowhole and are generally used to coordinate behaviour amongst individuals.1,2 This type of call can also be used for recognition of other individuals as Orca, like other dolphins, develop a signature pattern of clicks early in life which in effect functions as a name for them to announce themselves with or for others to call them by.2,3 “Whistles,” in the absence of vocal cords, are produced at varying levels of intonation by the larynx and are used primarily for close-range communication.1,4 What is most impressive in the way orca communicate is that they are able to combine different vocal signals in specific sequences in order to broaden the amount of information they can convey.5 Such advanced capacity for communication makes the language of the orca one of the most complex of any species.
Being so complicated, it takes a long time for a baby orca to learn to talk like the rest of their pod. Luckily though, mom is there to help. She will use a much greater diversity of calls when talking to her offspring than she would communicating with another adult, a kind of orca “baby talk.” Even so, it will take the young calf two years to master their pod’s entire repertoire of calls.1 Orca don’t all speak the same language though. Each pod, even in a single population, develops its own unique repertoire of calls. There is generally considerable overlap of calls common to multiple pods, especially across pods that interact frequently, and this allows a local dialect to be spoken between them.6 And so, like people, orca living great distances apart have developed entirely different dialects and even cultures.2
Our fascination with these animals may stem from an admiration of a resemblance we see in them to humans. Particularly in how successful they have been in colonizing the oceans as widely as we have the land and in the way they exhibit complex social structures and diversity of culture and language. Indeed, in many ways they are like us, and we are like them. And yet they are their own animal, and we should admire them as just that.
References
1. Kachar M, Sawosz E, Chwalibog A. Orcas are social mammals. International Journal
of Avian & Wildlife Biology. 2018;3(4):291‒295. DOI: 10.15406/ijawb.2018.03.00101
2. Wellard R, Erbe C, Fouda L, Blewitt M. Vocalisations of Killer Whales (Orcinus orca)
in the Bremer Canyon, Western Australia. PLOS ONE. 2015;10(10):
e0140738. https://doi.org/10.1371/journal.pone.0136535
3. Safina C. Beyond Words: What Animals Think & Feel (USA: Henry Holt Books,
2015), 313.
4. Thomsen F, Franck D, Ford JKB. On the communicative significance of whistles in
wild killer whales (Orcinus orca).
10.1007/s00114-002-0351-x
Naturwissenschaften. 2002;89:404-407. DOI
References
5. Riesch R, Ford JKB. Whistle sequences in wild killer whales (Orcinus orca). The
Journal of the Acoustical Society of America. 2008;124(3). DOI:
https://doi.org/10.1121/1.2956467
6. “About Whales: Killer whale.” International Whaling Commission, 01 Feb 2022,
https://iwc.int/killer-whale
