Galapagos Sperm Whales Have Specialized Family Cultures and Dialects

Sperm Whales and Calf from CBC News
(Chris Bangs/Guam Variety News/Associated Press)

We always want to be careful not to anthropomorphise those in the animal kingdom, whether it involves emotions, behaviors or language. After all, animals are not human and we can’t project emotions or thoughts onto them under the assumption that they think and communicate as we do. That said, we have learned from our own household pets how to read their “language” of gestures, looks and sounds and, from these, reach conclusions about whether they are hungry or want affection, are scared or tired or content. 

Even those observations, however, tell us nothing about how animals communicate with others of their own species. Is there a universal or even regional language that animals of a given species use with others of that same species? Scientists study language and other aspects of animal behavior all the time, forming hypotheses about what an animal's behaviors and vocalizations mean, if anything at all. 

In the Pacific Ocean around Galapagos we have thousands of sperm whales and calves. Scientists are intrigued by questions of sperm whale behaviors and communication. Recently, a study was published on the basis of research leading to the conclusion that Galapagos sperm whales actually do communicate with one another in clans, defined as a group consisting of several families. Each clan has a separate dialect or accent if you will. You can think of it as a local accent.

Sperm Whale Brain photo by Yamashita Yokel

Sperm Whale Brain photo by Yamashita Yokel

If brain size were the measure of intelligence, sperm whales would be geniuses. The sperm whale has the largest brain of any animal in the world, five times heavier than that of a human. But, in the end, that doesn't make it the sharpest of all creatures; for example it’s not as brainy as a dolphin. But, when it comes to communicating among themselves, sperm whales, it turns out, are pretty exceptional.

Over a period of 18 years, the vocalizations of sperm whales were studied. From watching and listening and noticing related behaviors, scientists concluded that sperm whales operate within family units and the families, in turn, operate within a sphere of clans, something like a separate culture or community. Even though all of the whales lived within a similar geographic area, each clan developed a separate coda, or pattern of communication and vocalization. These local accents are very unusual in the animal kingdom. The accents, the scientists say, are more like local human communities. Further, the accents are a learned cultural behavior, not instinctive. 

Photo from Wildwhales.com

To keep track of the whales and isolate their distinctive family and clan units, photographs of tails were matched to each whale since the ridges on a sperm whale’s tail are each unique – much like a fingerprint of a human. Computer simulations were used to follow the patterns and codas in order to define the units or communities of vocalizations.

Sperm Whales and Calves Photo from National Geographic

The scientists were able to determine too that these are not instinctive vocalizations but learned ones. What the team found is that social learning with bias, as opposed to pure social learning, is the most likely way whales learn codas. This means that the whales are biased towards learning certain codas, based on specific codas from whales in their own clans, or the most commonly used codas. This is similar to how human dialects evolve.

This post is based on the research study Multilevel animal societies can emerge from cultural transmission authored by Mauricio Canto, Lauren G. Shoemaker, Reneil B Cabral, Cesar O. Flores, Melinda Varga and Hal Whitehead, which was published in Nature Communications, September 8, 2015. The original study may be found online in the journal Nature Communications.