It’s not only us humans who have regional accents and dialects: Sperm whales do too, according to a new study published in Animal Behaviour. Researchers from the Domenica Sperm Whale Project have recorded and compared the various calls of whales over time. They found that Caribbean and Pacific whales have different “repertoires” of codas, the patterns of clicks whales make to each other when diving.
Further, different codas have different meanings, and whales can tell which member of their community is speaking based on the coda’s sound properties. Something called a “Five Regular” call is a pattern of five evenly spaced clicks that seem to be used to indicate the individual identity of a whale.
The researchers emphasized that the sperm whale is most threatened by human pollution and not only the junk we throw into the ocean. Noise is very much their enemy; more details from Science Daily:
Not only do humans introduce toxins into the ocean, but they also generate harmful sound pollution. Increased shipping traffic, underwater explosions caused by searching for oil, and military sonar all contribute to ocean noise that masks communication between whales. “No one wants to live in a rock concert,” says Mr. Gero, adding that noise pollution is especially troublesome in the ocean because “it is a totally different sensory world.” The sperm whales can dive to depths of over 1000 metres and depend on sound for communication and navigation in the pitch black of the deep water.
One researcher who is working on his Ph.D., Shaune Gero, is studying how whale calves acquire language. Like humans, baby whales babble first. Gero is “interested in discovering how the babies’ diversity of calls gets narrowed down to the family repertoire”: Sperm whales live in “matriarchal social units” composed of mothers, daughters and grandmothers. Adolescent males are “ostracized from the group and travel towards the poles until they are ready to breed” but female whales actually “baby-sit each other’s offspring while mothers are diving.”
The description of the whales’ codas fascinates me also because my teenage autistic son Charlie has minimal language, all of it acquired precious phoneme by phoneme, syllable by syllable. Charlie can use phrases of one to five words but often I find that it is the sounds and melodies that he makes that reveal a lot more about what he might be thinking and feeling. His articulation is still rather muddled and we often figure out what he is saying based on the tones, rhythms and melodies that Charlie utters. Indeed, “coda” might not be a bad word to describe some of the sound combinations that Charlie uses; these do have meaning (of distress, happiness, feelings of various sorts), if you have listened long enough and are willing to think that what sounds like random sounds indeed has meaning.
Here are sperm whales “resting, echolocating and communicating” off the island of Dominica in January of 2011:
Photo of two sperm whales by indi.ca