We have no idea of course. There are some documented songs that are very old. The best documented and often quoted as the 'oldest song in the world' is the Hurrian Hymn which was discovered in Syria inscribed onto a clay tablet and is nearly 3500 years old according to some sources. You can hear a recreation of it here. More recently there is the Sumerian 'Hymn to Creation' which goes back to 800 BC and then a wealth of Egyptian, Greek and Judaic tunes from 600 BC onwards. In terms of an old song that is still being sung today we should probably look to the Hindu orature which was passed down the generations from 1000 BC before being formalised.
As far as the oral tradition goes however, it is impossible to say how far back our folk tunes go, how many variations and misheard recreations have evolved through the centuries and who may have been the originator. Our species goes back over 30,000 years and our brains have evolved little in that time so any capacity for music we may have now was shared by our ancient ancestors.
I spend much of my professional life listening to people improvise tunes and it is fascinating how some melodies seem to persist. Are these tunes echoes of an ancient, pre-linguistic communication or more simply, fragments of shared melodies from modern day western musical culture? In one of our more experimental sessions we facilitate a group of people to sing together in the dark with no pre-conceived tune or accompaniment. In these sessions which can be very tribal in their feel, certain hooks, melodies and rhythms also seem to emerge with unerring regularity. You can hear the results of some of our experiments on our 'Singong' podcasts here.
I like to think that if we could listen in to the improvised singing sessions around fires 30,000 years ago that we would recognise fragments or even whole sections and that what sounded pleasing to those humans would still sound pleasing to us now. So next time you are whistling a random tune, or humming distractedly while washing up - just think - you could be unconsciously recreating a song from the earliest days of homo sapiens.
Heather Urquhart and Joe Samuel have over 15 years experience performing, teaching and writing about Musical Improv. Based in the UK they have facilitated workshops and graced stages around the world.