If you read my last blog, you know that sperm whales live in distinct cultural groups, called vocal clans, and that each clan speaks a unique dialect. From long-term research in the eastern Tropical Pacific and the eastern Caribbean, we know that clans can be distinguished based on their dialects alone, although they also differ in other aspects of behavior (like foraging, moving, and socializing). In more remote parts of the world or areas where research efforts are just beginning, this hard-won bit of knowledge has remarkable implications: by listening to recordings, we can make an educated guess about how many vocal clans live in an area without ever actually seeing those whales.
For much of my PhD, I’ve done just that: listen to hundreds and hundreds of recordings of the tap dance-like clicks of sperm whales. These hours spent listening are part of an international research effort (the Global Coda Repertoire Project, spearheaded by Dr. Shane Gero) to describe sperm whale vocal clans worldwide. Our goal is to get a better sense of how many sperm whale vocal clans exist around the globe and to characterize the dialect of each clan. A large-scale international project like this calls for an international team, and I’m working with 23 collaborators from 15 organizations (from academic, non-profit, and government sectors) to fill out the Pacific piece of the puzzle. That means analyzing codas from recordings that span huge swaths of the ocean: from New Zealand in the south to British Columbia in the north, Japan in the west to Chile in the east. Other collaborators are doing the same in the Atlantic and Indian Oceans. This ambitious, international, multi-year undertaking begs the question: why is it worthwhile to figure out how many vocal clans exist worldwide? The answer lies in conserving cultural diversity.
The pivotal role culture can play in driving the behavior of animals (including whales and dolphins) is increasingly being recognized, as are links between conservation and cultural diversity. On February 19, 2020, the Convention on Migratory Species formally recognized that animal culture should be linked to conservation action for several species, including chimpanzees and sperm whales. In these species and others, maintaining cultural diversity is likely just as important as maintaining genetic diversity when it comes to ensuring a healthy population of animals. This is where the Global Coda Repertoire Project comes into play: an essential first step in maintaining cultural diversity is understanding the current levels of cultural diversity, because that knowledge allows us to track changes in those levels over time. While we may not know what the whales are saying, we can at least study how differently they say it.
American feminist author Rita Mae Brown once said, “Language is the road map of a culture. It tells you where its people come from and where they are going.” In line with her thoughts, I would argue that dialects are the road maps of sperm whale cultures. The more maps we have—in other words, the better we do at preserving sperm whale cultural diversity—the more paths into the future that exist for this species. How many roads exist now? How many roads existed fifty years ago? And how many will exist fifty years from now?
In my final blog, I’ll join the rest of my OpenThink cohort in reflecting on the question, “What do we owe each other?” The answer, I think, is the same I would give if asked, “What do we owe the whales?”
Photo via Cat on Flickr
