When the music was played to seven pairs of adult cotton-top tamarins housed at the University of Wisconsin, the monkeys became more anxious and jittery when they heard the fearful monkey music. They then calmed down, and sometimes even foraged, upon hearing the affiliation-based music.
Regular human music was also played to the monkeys, which predictably showed little response, except for a very surprising, calming response to the heavy metal band Metallica.
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