Cetacean Culture: The Way Whales Do Things
It has long been believed that one of the primary divisions between humans and the rest of life on Earth is culture. We do what we do because of the culture we learned at our mothers knee, in the classroom, or, in the case of some of our less savoury traits, what we picked up in the school playground. Animals do what they do because of the genes they inherited from their parents - or so the theory went.
A few field biologists have begun to challenge this cultural divide. Jane Goodall, Bill McGrew and their colleagues studying chimpanzees across the width of Africa, have described rich local chimpanzee cultures. The chimps of Gombe use stones as tools in a certain way, groom each other in a particular way, yet those chimps living in neighboring Mahale do things quite differently. Painstakingly, the chimpanzee scientists have cut away the counter arguments of their critics that these differences could be due to genes or different environments in the field sites. No, they argue, a young Gombe chimp learns the Gombe culture, and so behaves the "Gombe way". Recently, orang-utan scientists have joined in, describing distinct cultural practices in different parts of their southeast Asian range. The anthropologists and psychologists who had been so vehement in their dismissal of non-human culture, seem to be retreating.
Until recently, the culture wars were restricted to land, with some peripheral aerial battles - the debates about bird cultures have been less impassioned than those surrounding the primates. However, whale scientists had long concluded that culture was alive beneath the waves. How else to explain the extraordinary songs of the humpback whale? No genetic mechanism, no environmental differences, could explain the ever-evolving, but conformist, songs which are so prominent on the humpbacks tropical mating grounds. It had to be culture. Other whale and dolphin behaviour, from multi-generational fishing co-operatives between bottlenose dolphins and human fishers in Brazil, to the spread of a strange new feeding method among the humpback whales off Cape Cod, Massachusetts, looked like culture. But all this was largely unknown to the students of chimpanzee culture and their antagonists.
An important turning point came at a meeting in Chicago in 2000, where presentations by chimpanzee and orang-utan scientists were interspersed with other presentations by those of us who study whales and dolphins. Parallel perspectives emerged, but there were also major differences: differences in the animals cultures and in how the scientists looked at them. We whale scientists got lots of ideas and support from the primatologists. This was important as we were about to suffer attacks from the same critics, plus even from some of our sceptical colleagues.
Much of what is known of chimpanzee culture is material, the distinctive ways that groups of animals use rocks and sticks for a variety of purposes. In contrast, there is only one putative material culture in cetaceans, the strange case of the bottlenose dolphins in Shark Bay, Australia, who put sponges on their beaks. Most good candidates for whale culture involve sounds: the songs of the humpback, bowhead and fin whales, the call dialects of orcas, and the strange codas (constructed out of patterns of clicks), of sperm whales. Another difference with great apes is in geographical patterning. Chimps have one way of doing things in one place, another somewhere else. In orcas, sperm whales, bottlenose dolphins, and probably much more widely through the cetaceans, distinct cultural groups use the same waters and interact. They have, in essence, multicultural societies, virtually unknown outside humans.
Luke Rendell and I have recently uncovered an extreme example of such interwoven culturally distinct groupings. Virtually all the sperm whale groups that we have recorded right across the South Pacific can be assigned to one of five cultural clans, each with a distinct dialect. These clans are huge, spanning oceans and including thousands of animals. Off the Galapagos Islands, the site of our most comprehensive studies, there are two common clans: the "Regular" clan whose favourite coda is a regularly spaced "click-click-click-click-click" and the "Plus-one" clan who prefer "click-click-click-[pause]-click". Groups seem to avoid group members of the other clan. They also have distinctive ways of using the Galapagos waters: the "Regular" clan groups hug the islands and have convoluted tracks, whereas "Plus-one" groups move in straighter lines, further from land. A "Plus-one" clan sperm whale off the Galapagos Islands is no more "just a Pacific sperm whale" than an 18th century MacDonald was "just a Scot".
When El Nino strikes, warming the Galapagos seas, it is the "Plus-one" clan that makes a better living from the unproductive waters. But in cooler conditions, which are more characteristic, the situation is reversed. The "Regular" clan groups feed better. With global climate change, the oceans are warming, and this is likely to increase both the rate of occurrence of El Ninos, and their intensity. So, I suspect, cultural diversity will be important for sperm whales as they face the massive changes that we are making to the ocean.
Thus, we should consider culture when we try to conserve the whales. I go further. I think that culture may well have affected the genetic evolution of animals like sperm whales and orcas, and that culture should become part of how we perceive and treat these extraordinary animals.
Author: Professor Hal Whitehead, Dalhousie University.
This article was first published in WDCS Magazine in 2003