Experimental evidence for core-Merge in the vocal communication system of a wild passerine

Abstract

One of the cognitive capacities underlying language is core-Merge, which allows senders to combine two words into a sequence and receivers to recognize it as a single unit. Recent field studies suggest intriguing parallels in non-human animals, e.g., Japanese tits (Parus minor) combine two meaning-bearing calls into a sequence when prompting antipredator displays in other individuals. However, whether such examples represent core-Merge remains unclear; receivers may perceive a two-call sequence as two individual calls that are arbitrarily produced in close time proximity, not as a single unit. If an animal species has evolved core-Merge, its receivers should treat a two-call sequence produced by a single individual differently from the same two calls produced by two individuals with the same timing. Here, we show that Japanese tit receivers exhibit antipredator displays when perceiving two-call sequences broadcast from a single source, but not from two sources, providing evidence for core-Merge in animals.

The ABC‐D of animal linguistics: are syntax and compositionality for real?

“…Still, at this point the ‘separate utterances’ theory remains a possible explanation. But Suzuki & Matsumoto (2022) very recently developed a new and remarkable argument to refute it. As a baseline, they set up an experiment in which an ABC‐D sequence triggers mobbing of a predator model (a bull‐headed shrike, Lanius bucephalus ), as illustrated in Fig.…”

“…Part of the experimental design of Suzuki & Matsumoto (2022). Alarm–recruitment sequences are produced from a single loudspeaker (A) or from two loudspeakers (B).…”

“…Suzuki & Matsumoto (2022) conclude that there is a crucial difference between separate utterances of ABC and then D, and a single utterance of ABC‐D . This is possibly the most important argument to have been published as part of this debate.…”

“…In the human case, if Ann says inside the house that it’s hot while Bill says outside the house that it’s humid , one cannot infer that it’s both hot and humid in the same place. But within Suzuki & Matsumoto’s (2022) experimental set‐up, both the one‐speaker condition (Fig. 3A) and the two‐speaker condition (Fig.…”

Mobbing calls of seven species of Parids under the paradigm of the FME-D combination

“…While the units present in bird song are rarely associated with a speci c meaning (i.e. phonocoding, Engesser and Townsend 2019) the close association between speci c calls and speci c meanings in call sequences are promising candidates for the exploration of notions such as compositionality (Zuberbühler, 2020), Merge (Suzuki and Matsumoto 2022) or referentiality (Evans 1997) in non-human animals.…”