The pictures in this BBC article suggest that earliest known musical instrument may have had a shakuhachi-like mouthpiece. It appears as if it only has two finger holes, and being that the aspect ratio, that is the ratio of length to circumference, seems to be more like that of a quena, it does not exactly fit the modern definition of shakuhachi. But then, it is estimated to be 42 or 43 thousand years old, so I would not expect it to fit the current definition.
The slightly newer model, shown in this article has a very deeply cut mouthpiece and four or five finger holes. The aspect ratio looks like it is even more severe than the earlier instrument, and it is apparent the use was not for the low, relaxing sounds of any modern flute, but shrill, whistle-like sounds. I would not be at all surprised if the instrument was intended to be used to imitate birds, possibly a tool to hunt with, and not necessarily as a musical instrument. This may seem to be be a less romantic view of our distant ancestors, but it is just as astounding to me that the entire modern world of flute playing may have started with bird calls on a instrument with a shakuhachi-like mouthpiece.
If it is true that the earliest music, 40 to 43 thousand years ago, was inspired by singing birds, things apparently have not changed all that much. One of the best examples is the painting of Pope Gregory, depicting a time only some 1500 years ago, with a dove sitting on his shoulder giving him inspiration for the medieval Gregorian chants:
Perhaps Tsuru no Sugomori, a traditional piece for shakuhachi that is said to express the joy and love inherent in cranes, is not in the significant place of being one of the last pieces learned by coincidence. Interestingly, the piece seems to draw upon the sound of the cranes fluttering and flapping more than the crane’s song, as that is more of a honking sound and not nearly as musically pleasant to listen to as songbirds.
It pleases me to think that so much music, and probably all flute music, is inspired by birds. It gives me a feeling of connectedness with nature, sharing a taste for melody with such an in-the-moment entity as birds. Interestingly, having just seen the Ridley Scott movie Prometheus and finding that the beings that engineered humans in the movie used a similar flute as a key to start their spacecraft, it is apparent that I am not the only individual placing a somewhat mystical importance on these ancient flutes.