Whale songs trend across Pacific

Australian researchers have found that male humpback whales in the same population group sing the same song but that any changes to the tune spreads to other pods. Abstract from Current Biology

Highlights

- Humpback whale songs have repeatedly moved east across the South Pacific
- The songs moved across the region in a series of cultural waves
- The waves frequently caused complete “cultural revolution” of the song
- The scale, rate, and repetition of these cultural changes are unparalleled

Summary

Cultural transmission, the social learning of information or behaviors from conspecifics, is believed to occur in a number of groups of animals, including primates, cetaceans, and birds. Cultural traits can be passed vertically (from parents to offspring), obliquely (from the previous generation via a nonparent model to younger individuals), or horizontally (between unrelated individuals from similar age classes or within generations). Male humpback whales (Megaptera novaeangliae) have a highly stereotyped, repetitive, and progressively evolving vocal sexual display or “song” that functions in sexual selection (through mate attraction and/or male social sorting). All males within a population conform to the current version of the display (song type), and similarities may exist among the songs of populations within an ocean basin. Here we present a striking pattern of horizontal transmission: multiple song types spread rapidly and repeatedly in a unidirectional manner, like cultural ripples, eastward through the populations in the western and central South Pacific over an 11-year period. This is the first documentation of a repeated, dynamic cultural change occurring across multiple populations at such a large geographic scale.

Media release from the University of Queensland

Humpback whales spread songs across the Pacific

Researchers at The University of Queensland have found that male humpback whales ‘change their tune' every year during their migration across the Pacific.

A study on whale song published today in the US journal, Current Biology, reveals a striking pattern of cultural change over a large distance, with the rate, scale and repetition unmatched in non-human culture.

UQ PhD student Ellen Garland said 11 different humpback whale song types were identified, which typically started in the eastern Australian population and spread in a step-wise fashion across the region to French Polynesia.

“I noticed that the songs moved quite rapidly through the six populations, usually taking two years to spread all the way across the region,” she said.

“This can compare to the game of Chinese whispers, except the song appears to be transmitted with little changes unlike a human sentence in the game.”

Ms Garland said songs had spread across whale populations suggesting acoustic contact or male dispersal between populations in the region.

“The reason we believe the song tends to travel east is because the eastern Australian population is the largest in the region and has a greater influence than the smaller Oceania ones,” she said.

Previous research has revealed that only male humpback whales sing and that song is a behaviour used in courtship and mating.

Ms Garland said all of the males in a population sang a similar song, but it was continually changing and evolving over time.

“Song can undergo evolutionary change, which occurs over a long period of time, or revolutionary change, where the males start singing a completely new song,” she said.

“We believe the song is continually changing because the males wish to be novel or slightly different to the male singing next to them.

“The way whales change their song can be compared to how humans follow fashion trends – someone starts a new trend and before you know it everyone starts wearing the same thing.”

The study is the first documentation of a repeated, dynamic cultural change occurring across multiple humpback whale populations across a large geographical scale.

It was undertaken in collaboration with the South Pacific Whale Research Consortium and investigated song similarity over an 11-year period within the South Pacific region focusing on the populations of eastern Australia, New Caledonia, Tonga, American Samoa, the Cook Islands and French Polynesia.

Media: Ellen Garland, 0406 965 475 or e.garland@uq.edu.au; or Erin Pearl (UQ Communications) 07 5460 1229 or e.pearl@uq.edu.au

See also reporting by

- ABC (Australia)
- Sydney Morning Herald
- BBC
- PhysOrg.com™ (this is worth a read)


Australian whales. Music trendsetters.