Sperm whales live in structured clans similar to early humans, new research shows.
Hal Whitehead, the study’s sole author and a professor at Dalhousie University, said clan systems are matrilineal and average about 20,000 women per clan.
This discovery will help understand the cultural system and non-vocal behavior of marine mammals, he said.
“As biologists, we often try to make sense of what we see by comparing species. And when we were looking for parallels to clans, the closest thing we could find was what some call groups ethnolinguistics,” he said. “Some people just call them clans of humans.”
by Whitehead research paperpublished in the journal Royal Society Open Science on January 10, indicates that clans are determined by vocalizations called “codas” that involve distinct sequences of clicks.
“Morse code-like” models
The article credits Taylor Hersh, one of Whitehead’s former students, for discovering seven female-led clans among the estimated 300,000 sperm whales in the Pacific Ocean, with each clan using a different dialect.
“I think what excited us the most was finding that different clans seemed to have these preferred vocalizations,” Hersh said.
When two clans overlap geographically, the whales are thought to code-switch, just as humans who encounter different cultural groups look for things that “set us apart from them,” she said.
Hersh, who is now a postdoctoral researcher at Oregon State University, analyzed dozens of sperm whale dialects, describing them as a “series of patterned clicks similar to Morse code.”
“A whole way of life”
Whitehead first discovered two clans using different dialects in the early 2000s, during a research trip to the Galapagos Islands with a colleague. He described one group going “click, click, click, click” and the other “click, click, click, pause, click.”
Two decades later, Whitehead said they still don’t know why sperm whales only socialize with members of their own clan and not members of another.
But his research paper indicates that dialects mark social divisions and that culture is the only possible explanation for differences between clans.
Whitehead said clans act in a “democratic” system when they hunt, navigate, communicate and make decisions. When attacked, they defend themselves together and protect the young by placing them in the center of the group, like hunter-gatherers.
“It’s a really exciting thing because the young sperm whale not only learns how to create click patterns, but also learns a whole way of life from its family members and other members of its clan,” he said. he declares.
Whitehead said his research is motivated in part by understanding how humans ended up with “extraordinary social structures” and by learning how another group of animals manage their lives.
“We can think about the things we have in common with sperm whales,” he said. “We’re learning all the time, and that makes us human. Without that, we really couldn’t do anything. With sperm whales, it’s the same.”