What is whale song for?

In 1971, Roger Payne and Scott McVay published an analysis of underwater recordings showing that humpback whales do not merely call; they sing. The sounds are organized like music: units built into phrases, phrases into themes, themes into songs lasting up to half an hour, repeated in bouts that can run for days. The recordings became a bestselling album and helped launch the whale conservation movement. The scientific question they opened is still open: what is the song for?

Why it matters

Whale song is the most elaborate acoustic display in the animal kingdom outside human music, produced by a brain that diverged from ours tens of millions of years ago. Its function bears on how complexity evolves in communication anywhere, including how ours did. And the song carries a second mystery with few parallels: culture. All males in a population sing the same song, the song changes continuously, and every few years a population’s song is abruptly replaced by one arriving from a neighboring ocean basin, a cultural revolution documented sweeping across the South Pacific from Australia eastward. Nothing else in nonhuman animals matches that combination of conformity and wholesale change, and explaining it would illuminate how traditions work in minds unlike ours.

What has been tried

The obvious hypothesis, that song attracts females as birdsong often does, has a stubborn problem: in decades of observation, females almost never approach singers. Playback experiments attract other males instead, suggesting song may mediate male-male interactions, advertising presence or negotiating space in a dispersed acoustic arena. Hybrid accounts propose the song functions in a lek-like chorus, with females attending to the soundscape in ways hard to observe. The revolutions have been tracked in detail: novel songs spread along migration routes and shared feeding grounds, and singers demonstrably learn from what they hear. Why males adopt the new song wholesale, whether novelty itself is attractive, or conformity is compulsory, remains contested. Meanwhile bowhead whales sing too, with dozens of songs per population and constant turnover, deepening the puzzle rather than resolving it.

Where the edge is

Function, audience, and the engine of the revolutions are all unsettled. The core difficulty is observational: the relevant events, a female’s choice, a rival’s retreat, happen at depth, at distance, in the dark.

What would count as an answer

Linking song variation to measured outcomes: matings, spacing, or contests, tracked with tags and arrays across enough whales to show what singing buys the singer, and what adopting the new song buys the adopter.