It’s surprisingly difficult to define music. Suggest a quality that all songs share, and it’s easy to find one that breaks the rule. “You can always point to John Cage’s 4’33”, which is just silence, and say well if that’s music, then there’s nothing universal about music,” said musicologist Patrick Savage. He should know. He and his colleagues spent the last several years looking for characteristics shared by songs from around the world. As expected, they found nothing that’s absolutely universal. But they did find a surprising number of things—18 in total—that the vast majority of songs have in common. Most music is performed in groups, for example, using a regular beat, fairly short, repeated rhythmic patterns, along with other characteristics that make it easier to play with others. The results not only show a lot of similarities between very different musical styles, but, as the video above explains, they also hint at why music evolved in the first place. The researchers identified another ten “universal relationships,” qualities that tend to occur together, like dancing with drumming. Their work supports the idea that music evolved to bring people together. For Patrick Savage, the results fit his experience as a musician. (He’s currently based in Japan, and even competes in Japanese folk music competitions.) “I find when I go to a new place, or a new country,” he said, “even if I don’t speak the language I can often just join in the dancing or clap my hands or drum circle or whatever and just connect with people and really share this bonding experience with them.”