Extremely interesting research.

And seems to emphasize that chimps are individuals with individual tastes — and that Loulis tends to be a “typical” youngster in his hard rock musical choices! LOL

Most of us have a mistaken impression (usually from television and movies) of chimpanzees as loud and boisterous individuals. Now, don’t get me wrong, chimpanzees can get pretty loud when they are excited; but for the most part they are relatively silent individuals.

Chimpanzees seem to find environmental noise to be a bit disruptive. The family at CHCI gets very excited and agitated when sirens or loud motorcycles pass by their home, for example. So music, as additional ambient noise, has the potential to be pretty disruptive, too. This may be because the vocalizations that chimpanzees make (and thus a lot of the noise in their natural environment) are tied primarily to the limbic system of the brain; this means that they are strongly related to emotions. Human speech sounds are corticalized, meaning that we have more conscious control over those sounds. But humans have plenty of emotional sounds, too. The sobs you make when crying, the guffaws you make when laughing uncontrollably, the noises you may shout when you hit your thumb with a hammer – these are all tied to the limbic system.

That said, while music is not a regular occurrence at CHCI, we have done some investigations into the chimpanzees’ preferences (if any) for music. Remember that we are first and foremost a sanctuary for this family of chimpanzees, so all research is with their cooperation and permission, and is designed to be as minimally disruptive to their lives as possible.

Fouts (1989) conducted a study to determine if the chimpanzees showed a preference between flute and clarinet music, as well as music in general. Two musicians, one with a flute the other with a clarinet, sat obscured behind a blind (to control for the novelty of interesting people with interesting new instruments). On each day for a week, one of the musicians played “Moon River” on the clarinet for one minute, followed by a minute of silence, after which the second musician played the same song (to control for possible preferences by the chimpanzees in musical styles) on the flute for one minute. Then the flute would play again for one minute, followed by a minute of silence, after which the clarinet would play for one final minute. (The order of the instruments was counterbalanced over each day to control for order effects.) Researchers recorded the time the chimpanzees spent in the room closest to the blind containing the musicians. Fouts concluded that no real preferences existed for flute over clarinet music. However, there were some interesting individual differences in preferences for listening to music, generally. Washoe and Loulis seemed to avoid the music, each spending less than 2 minutes over the week in the room closest to the music. Moja, Tatu, and Dar, on the other hand, seemed to prefer the music more. Each spent over 24 minutes in the closest room.

Simpson (1993) and Shea (1993) offer anecdotal information about a very brief study of preferences for recorded music, when the chimpanzees were still living in the psychology building. There, the chimpanzees had five rooms to live in. The researchers simultaneously played a different type of music in four of the rooms – classical music in one, soft rock in a second, hard rock in a third, and nature sounds in a fourth ¬ and kept the fifth room silent. The researchers recorded the chimpanzees’ behavior 10 minutes prior to starting the music, for 20 minutes while the music was playing, and for 10 minutes after the music was turned off. For the 10 minutes prior to the start of the music, the chimpanzees had very low arousal, most were sleeping. Some interesting differences appeared, though, when the music was turned on. Moja and Tatu groomed one another in the soft rock room. Dar was a little excited and moved to the room with the nature sounds and remained there for most of the time. Washoe spent a lot of time in the room with the classical music. Loulis spent most of the time in the room with the hard rock music. Loulis became very excited, pant hooting, and banging on the bench. When the music was all turned off, Dar and Loulis began to relax, Moja and Tatu continued to groom, and Washoe’s excitement level seemed unchanged.

For information on other researchers’ explorations into the music preferences of chimpanzees, you can look for the work of J. Fritz at the Primate Foundation of Arizona.

References

Fouts, H. (1989) Chimpanzees and music. Friends of Washoe, 8 (4), 14-16.
Shea, M. (1993) Music to the chimps’ ears. Friends of Washoe, 14 (3/4), 5-6.
Simpson, M. (1993) Do chimps prefer rock music? Friends of Washoe, 14 (3/4), 5