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.通过重新排列无意义语音组合以生成全新语义的能力，是语言的核心构成要素之一。尽管动物的发声常包含无意义声学元素的组合，但目前仍缺乏证据表明，重新排列这类组合能够产生功能各异的语义。本研究在澳大利亚干旱区高度协作群居的红冠弯嘴鹛（Pomatostomus ruficeps）的鸣叫声中，为这类基础语言能力提供了实证支持。我们通过声学分析、自然行为观察以及一系列控制性回放实验，证实该物种会利用相同的声学元素（A与B），通过不同排列组合（AB或BAB）生成两种功能迥异的鸣叫声。具体而言，在单一位置添加或省略一个语境下无意义的声学元素，会产生类似音位（phoneme）的对比差异，足以区分两种鸣叫声的语义。本研究结果表明，通过重新排列无意义语音以生成全新信号的能力，并非人类所独有。我们认为，这类音位对比构成了音位结构的雏形，同时也是迈向人类语言生成性音位系统的潜在早期演化步骤。