Metaphor is central to human language and cognition. It has also been proposed to play an important role in language evolution. For these reasons, the evolution of metaphor and the cognitive processes supporting it are an important explanatory target for evolutionary accounts of human language. Here, we focus on the evolution of one particular capacity supporting metaphor, that of analogy. We integrate data from comparative psychology and cognitive archaeology to investigate the evolution of analogy as well as its evolutionary foundations. We present evidence that many aspects of analogy display evolutionary continuity between humans and non-human animals. In addition, we propose that analogical capacities can also be inferred from the archaeological record by looking at productional diversity in tool-making. Overall, we argue that analogy as an important cognitive process supporting metaphor has deep evolutionary roots.

Polysemy is pervasive in modern language and represents one key factor that allows for the unlimited expressive potential of human language. One important process of historical meaning extension is that of metaphor (Anderson 2017). Recently, the paradigm of Experimental Semiotics has been proposed as a novel methodology to investigate semantic change (Bowerman & Smith 2022). In experimental semiotics, participants have to converge on a novel signalling system in the absence of a shared language. Here we adopt this approach to experimentally investigate the role of metaphor in meaning extensions. Specifically, we will present results of a study in which participants have to communicate about a novel meaning space in a referential communication game. Importantly, participants will only be able to use symbols for which they have previously established symbol-meaning mappings in a prior game. The results show to which degree participants make use of metaphor in in this task.