The Roots of Evolution: Why Chimpanzees Prefer the Polyrhythmic Beat of African Drums Over Western Pop

Everyone likes to mix up their musical preferences once in a while--except chimps. They always prefer listening to the rich, polyrhythmic pulse of African drums or Indian folk, according to a recent study published by the American Psychological Association.

As previous studies have illustrated how some nonhuman primates prefer slower tempos, current findings seem to more specifically show chimps' passion for certain patterns and beats. In other words, these animals are less likely to take pleasure listening in on westernized pop or classic rock. 

"Although Western music, such as pop, blues and classical, sound different to the casual listener, they all follow the same musical and acoustic patterns. Therefore, by testing only different Western music, previous research has essentially replicated itself," the authors noted, in a news release. 

For their research, 16 adult chimps from the Yerkes National Primate Research Center at Emory University were placed in two groups. Over 12 consecutive days starting with 40 minutes each morning, the groups listened to African, Indian and Japanese music via a portable stereo. Another stereo with no music was also placed near a different enclosure to rule out association with the object instead of sound from the music. All different types of music were played at the same volume, but in random order. Researchers observed the chimps and their interaction with the recorded locations every two minutes, via handwritten notes.

They discovered that when African and Indian music was played near large outdoor enclosures, the chimps spent significantly more time listening to the music than other types. However, when researchers played Japanese music the chimps were more likely to be drift away from the sounds that carried regular beats similar to Western songs.

"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," said study coauthor Frans de Waal, PhD, of Emory University.

But what exactly do chimps' musical preferences have to do with anything? A lot about evolutionary history, according to the study authors. 

"Our study highlights the importance of sampling across the gamut of human music to potentially identify features that could have a shared evolutionary root," added lead study author Morgan Mingle, BA, of Emory and Southwestern University in Austin.  

More information regarding the findings can be seen via the Journal of Experimental Psychology: Animal Learning and Cognition.