Pacific sperm whale ‘clans’ express their culture through songs.

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Pacific sperm whale ‘clans’ express their culture through songs. A new study reveals that seven separate “clans” of sperm whales exist in the wide Pacific Ocean, each with its own unique culture and language as expressed by musical click patterns.

This is the first time whales have been shown to use cultural markers to distinguish themselves, and they are remarkably similar to human cultural indicators such as language and body modification.

Years of research have failed to shed light on the meaning of the whales’ underwater songs, thus this discovery is also significant.

During rest periods near the surface between dives into deeper waters, sometimes more than a mile down, for prey like squid and fish, sperm whales often exchange streams of loud clicks with each other, according to bioacoustics and lead author of the study Taylor Hersh of the Max Planck Institute of Psycholinguistics in Nijmegen in the Netherlands.

Click streams are broken up into “codas,” and the sounds are dubbed “songs” by sperm whales, despite the fact that they aren’t particularly melodic and sometimes sound a little like hammering and squeaking (this is why Navy sonar operators used to call sperm whales “carpenter fish”).

Hersh noted that while the meaning of the sperm whales’ codas remains a mystery, the many dialects of the whales’ vocalizations may be easily identified. The latest research demonstrates that whales utilize “identification codas,” or short bursts of clicking similar to Morse code, to declare their allegiance to a given clan.

She remarked that “identity codas” were very specific to the many whale cultures.

She said that the study’s findings that sperm whales stress their languages when competitor clans are approaching (a telltale habit also seen among humans) explain why whales from different clans rarely contact with one another even when they share the same seas.

The research looked at recordings of sperm whale cries produced underwater over the course of more than 40 years at 23 different spots in the Pacific Ocean, from Canada to New Zealand to Japan and South America. More than 23,000 click patterns were derived from these and an AI system was employed to identify the unique identity codas among them.

Hersh claims that researchers have identified at least seven separate “vocal clans” of sperm whales dispersed around the Pacific.

Members of the same sperm whale tribe, which could number in the hundreds, have been heard making sounds from opposite ends of the Pacific Ocean, sometimes more than 9,000 miles apart. There may be as few as 360,000 sperm whales in the world’s waters, with nearly half of those residing in the Pacific.

With sperm whales living for up to 90 years, a grandmother and grandchild could be separated by nearly 150 years in age. Indeed, she concluded, “clans appear to be hundreds of years old, and perhaps even longer.”

Diving in the deep ocean for most of their lives means very little is known about sperm whale behavior because of their isolation from people. Hersh said there is evidence to suggest that various clans employ different strategies when hunting for prey, but more study is needed before scientists can determine how the identity codas in sperm whale songs reflect other distinguishing characteristics of their clan culture.

The vocal clans of sperm whales have been compared to human dialect groups by Gaper Begu, an assistant professor of linguistics at the University of California, Berkeley who was not engaged in the study.

He cited well-known linguistic research from the 1980s that revealed islanders on Martha’s Vineyard were more prone to highlight their distinctive island accents when speaking among non-islanders.

Similar to how sperm whales are more likely to use their clan dialect of clicks in areas where they are more likely to encounter members of other clans, researchers in the most recent study discovered that sperm whales do the same thing.

In an effort to understand what sperm whales are saying, scientists launched Project CETI, or the Cetacean Translation Initiative, a year ago, and Begu is a part of that effort. We hope that by combining language research with machine learning, we can better understand what sperm whales are saying to one another and eventually develop a way for them to communicate with other species.

Using microphones on whales and in the ocean, “we are starting to collect data,” he said. Through observing their actions, we are gaining insight into their society and habitat.

While it has long been known that sperm whales use codas to communicate, this discovery is the first to identify the codas used by different whale clans, and it will be essential in understanding the whales’ whole songs, he added.

Janet Mann, an expert on dolphins and whales and a professor of biology and psychology at Georgetown University who was not involved in the study, agreed that the findings could lead to a better understanding of sperm whale communication.

As the authors point out, “we still understand nothing about the function of sperm whale codas,” she wrote in an email. This is a significant step in understanding not only the significance of codas, but also the driving reasons behind the development of culture amongst animals.