If you ever run into a group of chimpanzees in a record store, you may find them congregating around the Indian classical section.
That's according to a new study that tested the musical tastes of humans' primate cousins. The researchers found that while chimpanzees shun the steadily strong beats common in Western genres, they like Indian ragas and Akan tunes from West Africa.
"Our objective was not to find a preference for different cultures' music," study co-author Frans de Waal, a primatologist at Emory University in Atlanta, said in a statement. Rather, the researchers used music from Africa, India and Japan to test how the primates reacted to specific acoustic characteristics, such as the ratio of strong to weak beats (or stressed to unstressed beats). [8 Humanlike Behaviors of Primates]
De Waal and colleagues said that similar studies in the past only tested how chimpanzees reacted to Western music. But even though the sounds of Western pop and classical might seem different to the casual listener, they share similar rhythmic patterns and intervals. Musical traditions from other cultures, however, may have fundamentally different properties. While a typical Western song might have one strong beat for every one to three weak beats, an Indian raga (or series of notes in a classical composition) might have one strong beat for every 31 weak beats in a long rhythmic cycle.
Previous studies that focused on Western tunes found that primates preferred silence over any kind of human music. One study, published in the journal Cognition in 2007, found that marmosets and tamarins would rather listen to no music than Mozart or a lullaby. For the new study, the researchers looked outside the Western canon and used Indian ragas, Japanese taiko and music from the Akan culture in West Africa.
Every morning for 12 days, the researchers played 40 minutes of music in the outdoor enclosures of 16 adult chimpanzees at the Yerkes National Primate Research Center in Atlanta. They discovered that chimps spent more time in areas where they could best hear the African and Indian music, but they fled to the quietier parts of their enclosure when the researchers played Japanese taiko music, which uses regular strong beats like Western music.
These apparent preferences could have something to do with the chimps' own music-making.
"Chimpanzees may perceive the strong, predictable rhythmic patterns as threatening, as chimpanzee dominance displays commonly incorporate repeated rhythmic sounds such as stomping, clapping and banging objects," de Waal said.
The findings, published June 23, are available online in the Journal of Experimental Psychology: Animal Learning and Cognition.