An Audience as a Pentatonic Scale Network
I recently stumbled across this video of Bobby McFerrin using the crowd at the World Science Festival as an instrument in his song. As Bobby jumps around on stage, the crowd produces the desired pitch according to his relative positioning. The discussion from which this clip was taken was centered around the connections between neuroscience and music, so Bobby uses this demonstration as part of a claim that humans have an inborn understanding of the notes in the pentatonic scale. I would argue, however, that this is a better demonstration of network effects than of our fundamental connection to music.
Rather than every individual audience member knowing the exact note to sing in response to Bobby’s position, they all know whether they should sing relatively lower or higher, but the degree of their change in pitch is determined by the singing around them. As a particular audience member hears the pitch being produced by the rest of the crowd around them, they will adjust their singing to match it. This effect could be modeled as the spreading of information of which pitch to sing throughout the network of the audience members. As any given audience member sings, they listen to the crowd around them to get a sense of what note they should be singing. Because this influence is spread throughout and looped back across all of the audience, the final note that is produced is the one that emerges as dominant among all of the initial notes being sung. Therefore, Bobby is in essence, using the “wisdom of the crowd” as his instrument rather than some innate Pentatonic Scale.
The participation of the crowd in this song also provides a good demonstration of behavior spreading through a network. It could be argued that each individual audience member gets more enjoyment from participating in the demonstration themselves if many other audience members are already doing so. If only a few people around them are participating, they might not want to single themselves out, whereas they will have more fun participating in the singing if everybody is going along with it. This explains why bobby has to instruct the same note multiple times in the beginning of the demonstration until enough people are on board for it to get past the tipping point and grow towards 100% participation. Also, on a local scale, people are probably more likely to sing along if their friends that they came with are also doing it. I think Bobby unknowingly tries to spread participation into these clusters by getting everybody to laugh when he split his legs. Because laughter is a very fundamental way for people to connect that spreads very easily, it has a very low threshold and can spread into most clusters of people. Perhaps once people felt connected along these lines, their clusters also became more likely to give way to the singing behavior.
Awesome as always!