Birdsong has long been compared to human music due to how pleasing it is to the ear. However, compared to the complex rules and theory behind human melody, birds are just children banging on pianos in the right way. Now, for the first time, one species of bird has been found to be following the complex rules of human music theory to a T.
That's at least according to a study recently published in the journal Proceedings of the National Academy of Sciences, which illustrates how the male hermit thrush (Catharus guttatus) sings melodies that employ the same mathematical principles that underlie Western and European musical scales.
According to the researchers, these findings "add to a small but growing body of research showing that a preference for small-integer ratio intervals [in melody] is not unique to humans."
They argue that instead, this could be a biologically-driven pattern. Musicality and a talent for crafting new songs is not entirely a child of human culture, but a product of a complex natural tendency as well.
The study details how researchers from both computational and musical backgrounds came together to analyze the characteristics of 71 songs containing 10 or more notes made by 14 male hermit thrushes.
Crafted statistical models showed that just over 80 percent of these songs closely resembled what musicians call a harmonic series - that is, when the variety of notes in a song follows a pattern of mathematical distribution.
The team adds that it's unlikely that this tendency is due to the simple structure of the birds' vocal tracts, as other songbirds boast similar tracts without singing the incredibly beautiful and flute-like songs of the hermit thrush.
Rather, the researchers argue that the thrushes are intentionally choosing to sing in these patterns, as they somehow know that it will be most appealing to female thrushes (and human ears) - creating catchy tunes both easy to remember and easily measured.