GridStream Productions

"In the study, 14 cotton-top tamarins were played 30-second blasts of music while the researchers noted any changes in their behaviour. The animals were played Samuel Barber's Adagio for Strings and a soft piano piece from The Fragile by rock band Nine Inch Nails, followed by Metallica's Of Wolf and Man and an excerpt from The Grudge by rock band Tool.

They then heard the specially composed monkey music.

The only human music that elicited any response was the heavy metal band Metallica, whose music had the unexpected effect of calming the monkeys."

Source
(Here you can also listen to the special "monkey music")

Source2

lol

Makes sense to me. Metal calms me down too. *makes monkey noises*

It has always been interesting to see how people in Metallica concerts often resemble more our distant cousins than fellow human beings. Perhaps this research supports the theory that Metallica fans are the missing link between apes and humans.