Study results contradict the nearly universal belief that humpback whales learn their songs from other whales

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Contrary to what most scholars would say, UB’s Eduardo Mercado III argues that the annual changes whales make to songs are entirely and profoundly incompatible with community copying. Photo: Douglas Levere

Release date: May 19, 2022

BUFFALO, NY – In calmer times when a ship’s progress at sea was only achieved by the wind, sailors told tales of intriguing sounds coming from humpback whales. If conditions were oddly calm and a ship, by coincidence or pursuit, found itself in close company with humpback whales, crews could hear a mysteriously beautiful call from the ocean that seemed to shimmer softly through the hull of their ship, like the faint, falling pitch of a struck tuning fork.

In 1952, marine mythology became scientific fact when a US Navy hydrophone off the coast of Hawaii recorded the songs of humpback whales.

Questions, however, remained and continue to persist.

It’s not clear why whales sing. Most research suggests courtship, a conclusion supported at least in part by the fact that singing is the exclusive ability of humpback males. Females utter some calls. As well as their calves. But only the males produce the familiar songs.

The purpose of whale song is still an unsolved riddle, but what is certain is that whales are not one-of-a-kind wonders. They systematically change their highly structured and sophisticated songs, a finding first reported in 1971.

The prevailing hypothesis of how this song morphing occurs, a conclusion drawn from over 50 years of research, is that vocal custom is the source of the changes. Whales learn socially from other whales, one of the rare examples of vocal culture in a non-human species. In the case of humpback whales, scientists overwhelmingly believe that new songs pass from innovative singers to groups of eager imitators.

Are whales imitators?

“No, they’re not,” says Eduardo Mercado III, PhD, professor of psychology at the University at Buffalo.

No evidence to support social learning

His research shows no evidence of social learning ─ none.

Mercado argues that the annual changes whales make to songs, despite current scientific consensus, are entirely and profoundly inconsistent with community copying.

BG: Am I right that your conclusion is contrary to what most researchers would say?

EMiii: Yes.

BG: Are there other scientists who support your conclusion?

EMiii: Nope.

BG: Not one?

EMiii: I’ve worked with co-authors on research into the potential purpose of whale song, but when it comes to results contradicting the social learning hypothesis, that’s just me.

Mercado vs. the Masses doesn’t seem to encourage the odds, but spend a few minutes with it. Ask about his research. He’s a compelling outlier. He speaks with equal speed and enthusiasm, every point accentuated with a confidence backed by extensive research. It’s so compelling that you wonder how the social learning hypothesis even survives.

“I don’t want to say everyone is wrong, but the evidence suggests they are wrong,” Mercado says.

“The idea of ​​cultural transmission was born in the 1980s, and it has stuck. It was as if culture became the answer because culture seemed to be the only explanation.

At one point, this explanation made sense to him.

“For decades I also thought singers learned new song content by copying other singers, but not anymore,” he says. “The accumulation of evidence has forced me to abandon this interpretation.”

This accumulation of evidence represents more than 20 years of research that has enabled Mercado to listen to whale songs. But is anyone listening?

Yes. In fact, momentum builds.

In the past two years alone, he has published a dozen studies in leading peer-reviewed scientific journals.

His 2021 whale song article with Christina E. Perazio, assistant professor of education at the University of New England, won the 2021 Frank A. Beach Comparative Psychology Prize for the best study that year in the Journal of Comparative Psychology of the American Psychological Association.

In this article, Mercado dismantles the common practice of designating the vocal sequences of whale song as screams, moans, and screams. He says it’s an arbitrary categorization that leads to problematic comparisons.

Not all sounds in each group are necessarily the same, and the nuance that distinguishes one scream from another, for example, could be as significant as the inflection in human speech that gives different meanings to otherwise identical phrases. , such as “I a m here” and “I am here.”

The new newspaper is a frontal assault on the status quo

But this is his last post which presents itself as a frontal assault, in direct contradiction to the status quo view of humpback whale song as a form of vocal culture. The results are published in the journal Animal Behavior and Cognition.

With this paper, Mercado says it’s time to take a step back, examine the predictions made by the social learning hypothesis ─ a presumption that even its most vocal proponents admit to having. never been tested ─ and examine the counter-evidence presented in his research.

“If singers are prone to copying new songs, exposing them to hit songs from other populations should spark imitation,” he says. “In a playback study examining humpback whale responses to familiar and unfamiliar songs, 71% of singers exposed to foreign songs swam away from the simulated immigrant, and no singer imitated the new song.”

The paper’s findings also show how problems arise in what previous research has called compelling evidence for song culture in humpback whales. This evidence involves studies suggesting how whales in an Eastern Australian population began to sing Western Australian wanderer songs.

“If innovations lead to cultural revolutions, then the waves that ripple unidirectionally through populations imply either that only western singers are innovative, or that non-Western Australian improvisers are always ignored” , explains Mercado.

Additionally, he points out that if more than one innovative singer comes along, there should be competing songs in a population.

“Fifty years of recordings have yet to reveal any evidence that such song battles occur in any population,” he says. “Given that there may be thousands of singers in a population, it is highly unlikely that a single whale would improvise new songs or make popular mistakes.”

Innovation is also about progression, so if innovations accumulate over time, there shouldn’t be any regression to previous songs; yet Mercado’s work shows how many phrases in whale song reappear.

But also consider that social learning involves being a “student in the classroom.” So if whales learn from each other, then distinct populations of whales should have distinct vocal customs. But they don’t, according to the paper’s findings. Humpback whale populations without acoustic contact with each other produce acoustically corresponding themes. Different populations separated by continents can sing the same songs without ever hearing any of the same inspirational patterns.

All of these factors not only point to a potential new direction of research, but are evidence that has increased Mercado’s respect for whales.

“All of this involves a different level of consciousness than social learning,” says Mercado, an expert in plasticity, or the brain’s ability to adapt and change through experience. “The current model is based on memory: whales hear a song; Hold that; and copy it. But what they actually do is more complex.

“We still don’t know what drives the song changes, but I’m convinced it’s not cultural,” he says.

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