Department of Fish, Wildlife, and Conservation Biology, Colorado State University, Fort Collins, CO, USA.
Department of Electronic and Computer Engineering, Colorado State University, Fort Collins, CO, USA.
Nat Ecol Evol. 2024 Jul;8(7):1353-1364. doi: 10.1038/s41559-024-02420-w. Epub 2024 Jun 10.
Personal names are a universal feature of human language, yet few analogues exist in other species. While dolphins and parrots address conspecifics by imitating the calls of the addressee, human names are not imitations of the sounds typically made by the named individual. Labelling objects or individuals without relying on imitation of the sounds made by the referent radically expands the expressive power of language. Thus, if non-imitative name analogues were found in other species, this could have important implications for our understanding of language evolution. Here we present evidence that wild African elephants address one another with individually specific calls, probably without relying on imitation of the receiver. We used machine learning to demonstrate that the receiver of a call could be predicted from the call's acoustic structure, regardless of how similar the call was to the receiver's vocalizations. Moreover, elephants differentially responded to playbacks of calls originally addressed to them relative to calls addressed to a different individual. Our findings offer evidence for individual addressing of conspecifics in elephants. They further suggest that, unlike other non-human animals, elephants probably do not rely on imitation of the receiver's calls to address one another.
人名是人类语言的普遍特征,但在其他物种中很少有类似的现象。虽然海豚和鹦鹉通过模仿被称呼者的叫声来称呼同类,但人类的名字并不是对被命名者发出的声音的模仿。不依赖于模仿所指对象发出的声音来标记对象或个体,极大地扩展了语言的表现力。因此,如果在其他物种中发现了非模仿性的名字类似物,这可能对我们理解语言进化具有重要意义。在这里,我们提出了证据,证明野生非洲象彼此之间用特定的叫声进行交流,可能不依赖于对接收者的模仿。我们使用机器学习来证明,无论呼叫与接收者的发声有多么相似,都可以根据呼叫的声学结构来预测接收者。此外,大象会对播放给它们听的呼叫与播放给其他个体的呼叫做出不同的反应。我们的研究结果为大象中对同种个体的特定呼叫提供了证据。它们进一步表明,与其他非人类动物不同,大象可能不依赖于模仿接收者的叫声来相互交流。