Just as the Beatles once revolutionized American music, a small band of whales seems to have introduced a new musical style to whales living off Australia's East coast. In little more than a year, the crooning visitors managed to make their tune the major local hit, according to a study in the 20 November issue of Nature.
In humpback whales, the vocalists are always male, and they apparently sing to impress females. Each population has its own "in" song, which gradually evolves. That happens when one crooner embellishes his tune with an extra trill or groan, and others in the area pick up the riff. Females probably get bored by the same old song, says bioacoustician Michael Noad from the University of Sydney in Australia, so males keep adding new fillips to spice things up. But switching to a completely different song is unheard of, Noad says; deviating so far from the norm might label the singer as weird, rather than irresistibly trendy, he speculates.
So Noad and his colleagues, who have studied whale songs for many years, were surprised when their hydrophones picked up a novel song in 1996, one that became dominant by late 1997 and the only thing on the charts in 1998. (Click here for the old and the new song.) "The main part of the change just happened over a couple of months," he says. "It was extraordinarily rapid." Initially, the team had no idea where the song had come from--until Noad listened to a tape of western Australia humpbacks. "It was an exact match, no doubt about it."
The team figures the western Australian whales must have introduced the song when they accidentally headed to the east during their annual migration from Antarctica. But he has no idea why their song became popular so fast.
"This is very surprising," says whale researcher and bioacoustician Adam Frankel of Marine Acoustics Inc. in Arlington, Virginia. Nobody had ever reported such a cultural revolution among whales before, Frankel says. "It's huge."