Music a mystery to apes left baffled by Bieber and Beethoven
If only Walt Disney had known, he might not have had hipster ape King Louie belt out "I wanna be like you" in The Jungle Book.
Scientists have learned that great apes including chimpanzees and orangutans like Louie have absolutely no appreciation of music.
In fact evidence suggests that the ability to comprehend and enjoy music is one of the most distinguishing features separating humans from their hairy cousins.
Chimps may share 96% of human DNA, but they turn a deaf ear to music, the research shows. It makes no difference whether they are listening to Beethoven or Bieber - it is all just meaningless sound to them.
To carry out the study scientists at the University of York created a "chimpanzee jukebox" that allowed captive chimps to select their favourite classical, pop or rock melodies, or simply tune into silence.
The animals, housed at Edinburgh Zoo and the National Centre for Chimpanzee Care in Texas, got to listen to works by Mozart, Beethoven, Adele and Justin Bieber.
But none of them showed any preference for any kind of music. Nor were they any more likely to choose a musical offering than silence.
Lead scientist Dr Emma Wallace, from the University of York's Department of Psychology, said: "These results suggest that music is not something that is relevant to captive chimpanzees and are supported by recent work with zoo-housed orangutans that were unable to distinguish music from digitally scrambled noise.
"These results also highlight the possibility that music appreciation is something that is a uniquely human trait."
Many zoos broadcast music to their primates in the belief that it improves the animals' living conditions. It is also popular with zoo keepers.
Dr Wallace said: "Whilst music does not appear to have a positive effect on captive chimpanzee welfare, it equally did not have any negative effects.
"As such it should not be considered a successful form of enrichment for these animals but, providing that the animals have the option to avoid it, music can still be played for animal care-givers."
Around 18 chimps in Edinburgh and 44 in Texas took part in the experiments.
The "jukebox" consisted of a touch-sensitive screen behind a grid which allowed musical choices to be made according to which part of it was pressed.
Dr Wallace told the Press Association: "I think it's more than likely that hearing music the way we hear it is uniquely human.
"More research needs to be done on this but recent studies do indicate that music appreciation is something unique to us.
"There is a theory that suggests that human language started off with chanting and singing, so potentially complex language co-evolved with music."
She added it was still possible that chimps might respond to non-melodic rhythmical drumming, but this was not investigated in the study.
"Adult chimps will drum on hollow tree logs as part of their aggressive display, so they might show a different reaction to that very strong rhythmical kind of sound," said Dr Wallace. "That's something people are looking at."
The study's findings are published in the journal Public Library of Science ONE.
The 1967 musical animation The Jungle Book was the last film Walt Disney personally produced and he died while it was being made. A live action movie with the same name was released last year by Walt Disney Pictures.