A musical evolution

SMALL PRINT:THINK OF YOUR favourite piece of music. Whether it's by Beethoven, The Beatles (right) or Justin Bieber, someone somewhere composed the melody.

But could music be evolved from sounds through the choices of thousands of people? An online experiment is putting that concept to the test at DarwinTunes.com, using an artificial system to look at how sounds change under the influence of consumers.

Participants listen to eight- second loops online and rate them from “I can’t stand it” to “I love it”. Each loop has a “digital genome” and the highest-rated loops can “mate” to produce the next generation of loops through random combinations of genomes, with mutations thrown in too. Offspring loops then replace their parents.

A new study in the Proceedings of the National Academy of Sciences describes the outcomes when almost 7,000 consumers made more than 85,000 ratings over the course of 2,513 generations of evolution, during which 50,480 loops were born.

The loops quickly became easier to listen to within around 500 to 600 generations, report the authors, but then the appeal started to plateau. “Thus, in our system, musical quality evolves, but it seems that it does not do so indefinitely,” they write.

In the experiment, consumer selection helps to shape the sounds, but the authors note that for the music we listen to, other factors have their parts to play too.

“Humans do compose music before releasing it for public consumption, and consumers do not choose the music they like entirely on the basis of aesthetic quality but are also influenced by the preferences of others.”

You can hear and read all about the experiment at darwintunes.com.