Monkeys Like Happy Monkey Music (and Metallica)

As anyone who has a favorite (and least-favorite) musical artist knows, music can affect our moods. Now it seems it can do the same for cotton-top tamarin monkeys, but only when the music is composed specifically for them, according to a study published in the journal Biology Letters. Except for one anomaly (they liked Metallica), the monkeys didn't respond to samples of human music--but the tamarins did respond to cello music that was reminiscent of their natural calls. Cellist and composer David Teie studied recordings of both happy and upset tamarins, and used them as the bases for two different kinds of monkey music.