That’s certainly what McDermott thought when he first started studying music 15 years ago. But he has since changed his mind.

Five years ago, he and his colleagues started working with the Tsimané (pronounced ‘chee-mah-nay’)—an Amazonian society with barely any exposure to Western music. And they, to McDermott’s surprise, don’t care about consonance or dissonance. They can tell the difference between the two kinds of sounds, but they rate both as being equally pleasant.

“This puts the final nail in the coffin of biological accounts of consonance,” says Sandra Trehub from the University of Toronto, who was not involved in the study. “We become progressively attuned to the music of our culture, which makes it seem ‘natural’. Other cultures with different musical systems consider their music equally ‘natural’.”

Until now, studies of consonance and dissonance, like many other areas in psychology, have been restricted to WEIRD people—that is, those from Western, Educated, Industralized, Rich, and Democratic nations. “There’s been very little data from people from other cultures,” says McDermott. So when anthropologist Ricardo Godoy contacted him and offered him a chance to work with the Tsimané, he leapt at the chance.

The Tsimané live in remote villages in the Amazon rainforest, with no electricity or tap water. They have no televisions and limited access to radios, so they only encounter Western culture during their brief forays to nearby towns. Indeed, to get to them, McDermott had to fly to La Paz, Bolivia, drive along dirt roads into the Amazon, and paddle up-river in a canoe.

He worked with 64 Tsimané villagers, asking them to rate the pleasantness of synthetic tones and recorded notes, all played through headphones. When he did the same for US citizens, they preferred consonant chords over dissonant ones. So did city-dwellers from La Paz and residents of a rural Bolivia town, albeit to a weaker extent. But the Tsimané? They didn’t care. A few years later, McDermott’s team repeated the study with a different group of 50 villagers, this time playing them pitch-shifted recordings of their singing peers. Again: no preference.

It’s not that the Tsimané misunderstood the task; they predictably preferred laughter over gasps, just like Western listeners. It’s not that they can’t distinguish between consonant and dissonant intervals, either. They could; they just didn’t prefer one over the other.

There’s other evidence for this in other cultures, albeit not through experiments. Trehub says that scientists have long ignored ethnomusicologists’ descriptions of cultures that make deliberate use of dissonant intervals, like Balinese musicians who seem to intentionally “mistune” their instruments, or Croatian duettists who sing the same melody one semitone apart. “They’ve also ignored Western music history with its changing perspectives on consonance and dissonance,” she adds. “And they’ve celebrated studies that report preferences for consonant sounds in infancy, implying innateness, while ignoring studies that fail to find such preferences.”