“Roughly forty-three thousand years ago a young cave bear died in the rolling hills on the northwest border of modern-day Slovenia. A thousand miles away and a thousand years later, a mammoth died in the forests above the river Blau near the southern edge of modern-day Germany. Within a few years of the mammoth's demise, a griffon vulture also perished in the same vicinity. Five thousand years after that a swan and another mammoth died nearby.

We know almost nothing about how these animals met their deaths. They may have been hunted by Neanderthals or modern humans. They may have died of natural causes or been killed by other predators. Like almost every creature from the Paleolithic era the stories behind their lives and deaths are a mystery to us, lost to the un-reconstructible past.

But these different creatures, lost across time and space, did share one remarkable posthumous fate. After their flesh had been consumed by carnivores or bacteria, a bone from each of their skeletons was meticulously crafted by human hands into a flute.

Bone flutes are among the oldest known artifacts of human technological ingenuity. The Slovenian and German flutes date back to the very origins of art. The caves where some of them were found also featured drawings of animals and human forms on their walls, suggesting the tantalizing possibility that our ancestors gathered in the fire lit caverns to watch images flicker on the stone walls, accompanied by music.

But musical technology is likely far older than the Paleolithic. The Slovenian and German flutes survived because they were made of bone but many of the indigenous tribes in modern times construct flutes and drums out of reeds and animal skins, materials unlikely to survive tens of thousands of years.

Many archaeologists believe that our ancestors have been building drums for at least a hundred thousand years, making musical technology almost as old as technology designed for hunting or temperature regulation. This chronology is one of the great puzzles of early human history.

It seems to be jumping more than a few levels in the hierarchy of needs to go directly from spearheads and clothing to the invention of wind instruments. Eons before early humans started to imagine writing or agriculture they were crafting tools for making music. This seems particularly puzzling because music is the most abstract of the arts. Paintings represent the inhabitants of the world that our eyes actually perceive: animals, plants, landscapes and other people.

Architecture gives us shelter. Stories follow the arc of events that make up a human life. But music has no obvious referent beyond a vague association with the chirps and trills of birdsong. No one likes a hit record because it sounds like the natural world. We like music because it sounds different from the unstructured noise of the natural world. And what sounds like music is much closer to the abstracted symmetries of math than any experience a hunter-gatherer would have had a hundred thousand years ago.

A brief lesson in the physics of sound should help underscore the strangeness of the archaeological record here. Some of the bone flutes recovered from Paleolithic cave sites are intact enough that they can be played, and in many cases researchers have found that the finger holes carved into the bones are spaced in such a way that they can produce musical intervals that we now call perfect fourths and fifths.

In the terms of Western music, these would be F and G in the key of C. Fourths and fifths not only make up the harmonic backbone of almost every popular song in the modern canon, they are also some of the most ubiquitous intervals in the world’s many musical systems. Though some ancient tonal systems, like Balinese gamelan music, evolved without fourths and fifths, only the octave is more common. Musicologists now understand the physics behind these intervals and why they seem to trigger such an interesting response in the human ear.

An octave, two notes exactly twelve steps apart from each other on a piano keyboard, exhibits a precise 2:1 ratio in the wave forms it produces. If you play a high C on a guitar, the string will vibrate exactly two times for every single vibration the low C string generates. That synchronization, which also occurs with the harmonics or overtones that give an instrument its timbre, creates a vivid impression of consonance in the ear, the sound of those two wave forms snapping into alignment every other cycle.

The perfect fourth and fifth have comparably even ratios: a fourth is 4:3, while a fifth is 3:2. If you play a C and G note together, the higher G string will vibrate three times for every two vibrations of the C. By contrast, a C and F# played together create the most dissonant interval in the Western scale: the notorious tri-tone or ‘devil’s interval, with a ratio of 43:32.

The existence of these ratios has been known since the days of ancient Greece. The tuning system that features them is often called Pythagorean tuning after the Greek mathematician who, legend has it, first identified them. Today the average seventh grader knows Pythagoras for his triangles, but his ratios are the cornerstone of every pop song on Spotify.

The study of musical ratios marked one of the very first moments in the history of knowledge where mathematical descriptions productively explained natural phenomenon. In fact, the success of these mathematical explanations of music triggered a two-thousand year pursuit of similar cosmological ratios in the movements of the sun and planets in the sky; the famous ‘music of the spheres’ that inspired Kepler and so many others.

Wave forms, integer ratios, overtones …

None of these concepts were available to our ancestors in the Upper Paleolithic. And yet, for some bizarre reason they went to great lengths to build tools that could conjure these mathematical patterns out of the simple act of exhaling. Put yourself in that Slovenian cave forty thousand years ago. You have mastered fire, built simple tools for hunting, learned how to craft garments from animal skins to keep yourself warm in the winter.

An entire universe of further innovation lies in front of you. What would you choose to invent next? It seems preposterous that you would turn to crafting a tool that created vibrations in air molecules that synchronized at a perfect 3:2 ratio when played together. Yet that is exactly what our ancestors did.”

Wonderland: How Play Made the Modern World ~ Steven Johnson