Perhaps not surprising, but fascinating to think of how it went from "doesn't exist" to "connect two gourds with twine, speak and listen." When it didn't exist, what phenomenon or technology might have provided the hint that connecting two gourds together would transmit sound?
In researching the history of musical instruments, I discovered that many distant cultures independently developed hunting bows and it is believed these are the original of stringed instruments.
So, the concept of a taught string bound to a resonating body, simple as it is may have been a precursor.
It is possible gourds where used as mounting points on some of the contraptions, and the ability of hollow spaces to resonate was probably already known... which leads to Capoeira-like instruments...
but the next leap of getting the thing to pick up voice is imo a larger conceptual leap. Of course, by then, written language was widespread and ideas could maintain a bit more momentum...
Yet still, notice how the bottom of the cup is of a different material and not tightly coupled to the rest of the cup. It's attached with a woven or knitted "sock." That's where energy leaves the system instead of bouncing energy back into the twine like bows. That's a great conceptual leap, considering it's not totally obvious to most people today how the bridge of stringed instrument works :)
I imagine they had built large string and hollow-body resonator combinations...
Yet it's yet another step to make it "input-"sensitive to human voice :)
It mentions that this was a culture without written language. I wonder if that was important - once you develop writing, it might be easier to pass notes than invent this.
The Incas that followed them had recorded language. I doubt it is really known positively that Chimu had no recorded language. There are quite a few peoples groups in the western hemisphere for which it is commonly asserted by outsiders they had no recorded language, but once you start studying them at all, you find they have a recorded language.
they probably recognized sound as just vibrations in materials. it's a pretty straightforward observation, in my opinion. actually thinking of using a string in that way is the "outside the box" part
i think generally ancient people don't get the credit they deserve. they weren't dummies. even now-silly-sounding ideas (e.g. geocentric model) had logic to them (e.g. stars had no apparent parallax)
One thing you come to appreciate through the study of history is that people weren't stupid. Just because they don't have iPads and blogs doesn't mean they were less capable, as individuals or as a group. If you compare the current state of elected officials today to 200 years ago, you'd come to appreciate it too.
An interesting thought experiment is to assume a group of engineers, with perfect understanding of our modern technologies and how to make them travel back in time to the stone age. How long would it take for them to arrive back at our current technology knowing what the critical path to do so would be?
The single-person question is an interesting one. My instinct is to say: "let's try it". Of course I begin by performing a mental simulation. And it then occurs to me that this might be expensive, time-consuming, very, very difficult (especially obtaining materials!) but most of all dangerous. I suddenly wonder how many people have been maimed or killed developing modern (manufacturing, especially) techniques. Even if it's possible for one person to do; what are the odds of survival?
Ok let's make intermediate challenges, maybe not current tech, just enough to survive comfortably. Function of some context (different paths whether you start in Africa or Russia because of material, climate and such)
- math/physics knowledge to assemble tools
- having regular heat sources
- building a small shelter
- regular nutrient sources
then there's room for
- increasingly precise and versatile tools
- finding ways to generate and store electricity (wind, water)
- light
- optics
- radiowaves/communication
Stringed instruments, if part of the local culture, would provide another hint.
I'd also guess that strings would sometimes be used for crude 'stop/go' or 'come here' communication over distances, via tugs – perhaps ringing a bell or drum at the far end. One person at the 'clapper' element, noticing a hint of vibrations/sound from the distant end, via the string, in more resolution than a discrete tug/ring, might get the necessary insight.
Sound is essentially vibration. Challenge to making phone is to capture that vibration, transmit it for some distance, and then reproduce it. To make such a device you need to understand that. I think that is what makes this discovery fascinating. In advent of modern technology we often discount ingenuity of the past. Makes you wonder how many people hailed for making world changing technologies simply improved on what was already there.
Quipus are interesting: using knots in string to encode columns of decimal numbers. They also had a device (made of beans and slots) for doing calculation (similar to how an abacus works I guess). The Incas had spreadsheets.