Evolutionary Linguistic Theory - Volume 2, Issue 2, 2020

Regularities in natural language systems, despite their cognitive advantages in terms of storage and learnability, often coexist with exceptions, raising the question of whether and why irregularities survive. We offer a complex system perspective on this issue, focusing on the irregular past tense forms in English. Two separate processes affect the overall regularity: new verbs constantly entering the vocabulary in the regular form at low frequency, and transitions in both directions (from irregular to regular and vice-versa) occurring in a narrow frequency range. The introduction of new verbs leads to an increase in regular types, that, entering at low frequencies, have a small impact on the perceived irregularity in terms of tokens. The frequency of usage acts as a control parameter, the majority of verbs types being fully-regular(irregular) at low(high) frequencies, with no evidence of irregularity facing extinction. Very few verbs types in an intermediate frequency region exhibit both regular and irregular forms at the same time, suggesting that the coexistence is unstable. The observed pattern of usage showing an abrupt change in response to small variations of the control parameter only appears in agent-based models provided that the word state is non-binary. By introducing this key ingredient, high-frequency irregular past-tense can survive the tendency to regularize over time, as observed in natural languages.

An evolutionary approach to historical linguistics can be enlightening when not only the mechanisms, but also the statistical methods are considered from neighboring disciplines. In this short paper, we apply survival analysis to investigate what factors determine the lifespan of words. Our case study is on post-classical Greek from the 4th century bc to the beginning of the 8th century ad. We find that lower frequency and phonetically longer lexemes suffer earlier deaths. Furthermore, verbs turn out to have higher survival rates than adjectives and nouns.

This paper discusses the view that subjectifications (i.e. semantic changes through which words come to index speakers’ evaluations or their attitudes towards a proposition) are primarily motivated by speakers’ need for self-expression (Traugott 2010). Approaching the issue from the perspective of animal signalling (Krebs & Dawkins 1984), we propose that semantic subjectifications are at least equally likely to reflect evaluations and attitudes read into utterances by listeners who attempt to read speakers’ minds. We compare speaker-based and listener-based theories with regard to their predictions, sketch ways in which they can be tested and report findings from first attempts at doing so. First, we report evidence from diachronic corpora. Second, we describe a game-theoretic model that relates listener’s interest in speaker intentions to the average degree of speaker-honesty in a population. Third, we report preliminary results of an experiment in which we tested if listeners were more likely to interpret an utterance as indexing speaker subjectivity when they perceived speakers as more powerful. We conclude that the listener-based hypothesis of subjectification is solid enough to warrant further investigation.

In recent years, multiple researchers working on the evolution of language have put forward the idea that the theoretical framework of usage-based approaches and Construction Grammar is highly suitable for modelling the emergence of human language from pre-linguistic or proto-linguistic communication systems. This also raises the question of whether usage-based and constructionist approaches can be integrated with the analysis of animal communication systems. In this paper, we review possible avenues where usage-based, constructionist approaches can make contact with animal communication research, which in turn also has implications for theories of language evolution. To this end, we first give an overview of key assumptions of usage-based and constructionist approaches before reviewing some key issues in animal communication research through the lens of usage-based, constructionist approaches. Specifically, we will discuss how research on alarm calls, gestural communication and symbol-trained animals can be brought into contact with usage-based, constructionist theorizing. We argue that a constructionist view of animal communication can yield new perspectives on its relation to human language, which in turn has important implications regarding the evolution of language. Importantly, this theoretical approach also generates hypotheses that have the potential of complementing and extending results from the more formalist approaches that often underlie current animal communication research.

There has been a long-standing controversy in the context of language evolution on whether the original function of human language was internal thought or external communication. However, given the fact that language clearly serves both functions, internalization and externalization must have been co-evolutionarily acted in the emergence of human language. This article proposes a theoretical hypothesis about this co-evolutionary relationship of internalization and externalization, which especially explains the emergence of the human lexicon. To discuss the evolution of language from a comprehensive perspective, this article proposes a promising model that integrates two approaches with different standpoints: generative grammar and cognitive linguistics. This paper also examines the definition and nature of the lexicon and lexical items based on this integrated model. The hypothesis presented here demonstrates that the co-evolutionary work of internalization and externalization has been involved in two processes in the development of the lexicon: the establishment of syntactic objects (lexical items) and the improvement of creativity responsible for the expansion of lexicon size. The main conclusion is that these processes have formed a positive feedback loop and provided our lexicon with complex and unique properties.