A bird species derives different meanings from varying combinations of notes, just as humans understand complex meanings from words combined in different ways.

Credit: Takao Onozato/Aflo/Getty

Toshitaka Suzuki of the Graduate University for Advanced Studies in Hayama, Japan, and his colleagues played recordings of four notes — A, B, C and D — in different orders for the Japanese great tit (Parus minor; pictured), which normally uses more than ten different notes in its calls. Playing ABC prompted the birds to scan horizontally for predators. On hearing a repeated D note, the birds approached the source of the calls. ABC–D calls elicited both behaviours, but playing D–ABC invoked little or no response.

The authors suggest that the order of the notes determines meaning, and say that this is the first experimental evidence for 'compositional syntax' in a wild animal.

Nature Commun. 7, 10986 (2016)