Birdsong and whale song show patterns similar to human language

An international research team led by scientists from the University of Edinburgh, Hebrew University of Jerusalem, and Teikyo University in Japan has discovered a previously unknown structure in the song of Bengalese finches. This discovery reveals that birdsongs contain statistical patterns similar to those found in human languages.

The finches' complex, learned songs are organized using the same mathematical formula as human speech, suggesting that this trait has evolved over time to facilitate complex communication and make it easier to learn and pass down from one generation to the next.

The study, published in the journal Science Advances, builds on a previous finding that humpback whales also utilize a similar systematic structure in their communication. The researchers employed methods inspired by how babies learn to recognize words in human speech and applied them to bird song data collected from finches in Japan.

They observed that the finches' songs consist of statistically coherent sequences of notes, akin to the "words" in human language. These sequences follow a Zipfian distribution, where a few notes are used frequently while others are used less often. This pattern was evident from the birds' earliest attempts at singing, indicating that it emerges naturally as part of the learning process.

The young songbirds learn the statistical patterns of their songs by listening to the sounds around them, similar to how human infants learn language. This statistical process is believed to make language easier to learn, helping infants identify recurring chunks of speech within the continuous stream of sounds they hear daily. The lead researchers, along with Dr. Ellen Garland from the University of St. Andrews, also found similar patterns in the songs of humpback whales.

The study suggests that the fundamental building blocks of learnable language can emerge wherever communication is learned and passed down through generations, even in the songs of small birds.

Professor Simon Kirby, co-leader of the research, remarked on the surprising commonality between species separated by over 300 million years of evolution. He explained that both humans and songbirds transmit their communication through culture, which creates the patterns shared by language and birdsong. The researchers emphasize that while humans are the only species with language, they are not unique in having culturally evolving communication systems.

This finding challenges the notion that language is uniquely human, highlighting the potential for evolutionary convergences in complex communication systems across diverse species.