Every bird song in the world made of just eight notes, study finds

Bengaluru: From the musical whistles of a red-whiskered bulbul to the mechanical whirr of a barn swallow, there is incredible diversity in avian music. But according to a new study by researchers from France and the U.S., this vast diversity comes from just eight building blocks.

Researchers analysed more than one lakh song recordings from over 3,000 passerine bird species worldwide using machine learning to reveal eight core motifs, or basic sounds.

The study found that birds, on average, use five motifs, and which ones they use depends largely on their evolutionary history.

The same study also found that in tropical rainforests such as in Southeast Asia, birds prefer simpler songs that travel efficiently through dense vegetation. In temperate regions such as Europe and North America, on the other hand, birds have small territories and short breeding seasons, and so produce complex, information-rich songs.