Data from: Experimental evidence for phonemic contrasts in a nonhuman vocal system

The ability to generate new meaning by rearranging combinations of
meaningless sounds is a fundamental component of language. Although animal
vocalizations often comprise combinations of meaningless acoustic
elements, evidence that rearranging such combinations generates
functionally distinct meaning is lacking. Here, we provide evidence for
this basic ability in calls of the chestnut-crowned babbler (Pomatostomus
ruficeps), a highly cooperative bird of the Australian arid zone. Using
acoustic analyses, natural observations, and a series of controlled
playback experiments, we demonstrate that this species uses the same
acoustic elements (A and B) in different arrangements (AB or BAB) to
create two functionally distinct vocalizations. Specifically, the addition
or omission of a contextually meaningless acoustic element at a single
position generates a phoneme-like contrast that is sufficient to
distinguish the meaning between the two calls. Our results indicate that
the capacity to rearrange meaningless sounds in order to create new
signals occurs outside of humans. We suggest that phonemic contrasts
represent a rudimentary form of phoneme structure and a potential early
step towards the generative phonemic system of human language.