By the time you read this, I’m afraid, it’ll be too late to attend the Christmas concert of the community choir to which I’ve belonged for a while now. I know, I know, you’re gutted. But maybe it’s better that way: the weekly rehearsals have become such an oddly transporting highlight of my week that it almost feels too personal to mention in public. I’m not alone in this, I realise. These days, with amateur singing exploding in popularity, there’s no happiness advice less original than “Join a choir!” So it’s strange that we still don’t really understand why it feels so good. In 1997, when Steven Pinker wrote How The Mind Works – a book that explains almost everything you think or feel in terms of evolutionary advantages – even he couldn’t think of one for music. It was probably just “auditory cheesecake”, he concluded: a fun but pointless extra we get as a byproduct of language.

Perhaps. But there are hints to the contrary in new research from Goldsmiths college, comparing the benefits of singing in big and small groups. The participants belonged to Popchoir, a network of smaller choirs that occasionally meet to sing in a 232-person “mega-choir”. That meant researchers could account for the argument that the main benefit is just hanging out with friends: members of the small choirs knew each other, but the mega-choir members mainly didn’t. Yet the impact of a 90-minute rehearsal on singers’ sense of social bonding was bigger for the large group. Before and after rehearsals, singers also wore blood pressure-monitoring cuffs, inflated until they experienced extreme discomfort; singing, it turned out, also increased their pain threshold.

One possibility here, then, is that singing facilitates bonding in groups that would otherwise be too large to coordinate, giving them a clear survival advantage when clashing with enemies, among other things. It could even be that “our ancestors turned loud singing into a central element of their defence system against predators”, writes Joseph Jordania, an ethnomusicologist, in Why Do People Sing? “They started using loud, rhythmic singing and shouting accompanied by vigorous, threatening body movements” to terrify opponents. My faltering attempt to make it through a Haydn fugue, in other words, might have its origins in something more akin to a Maori haka.

But anyone who has ever sung in a choir already knows it’s about more than hanging out with friends. Group singing is a perfect case of the whole being greater than the sum of its parts. For entirely non-magical reasons – such as the averaging out of flat and sharp voices – a choir can sound far better than its individual members’ talents might suggest. The result is self-transcendence: the thing only works on a level bigger than oneself. “As long as I’m singing,” writes Stacy Horn in Imperfect Harmony, her memoir of singing in a Manhattan amateur choir, “it’s as if I’m inhabiting another reality. I become temporarily suspended in a world where everything bad is bearable, and everything good feels possible.” There are worse ways to spend an evening.