What are the Units of Language Evolution? Nathalie Gontier Topoi An International Review of Philosophy ISSN 0167-7411 Volume 37 Number 2 Topoi (2018) 37:235-253 DOI 10.1007/s11245-017-9474-8 1 23 Your article is protected by copyright and all rights are held exclusively by Springer Science +Business Media Dordrecht. This e-offprint is for personal use only and shall not be self- archived in electronic repositories. If you wish to self-archive your article, please use the accepted manuscript version for posting on your own website. You may further deposit the accepted manuscript version in any repository, provided it is only made publicly available 12 months after official publication or later and provided acknowledgement is given to the original source of publication and a link is inserted to the published article on Springer's website. The link must be accompanied by the following text: "The final publication is available at link.springer.com”. 1 23 Author's personal copy Topoi (2018) 37:235–253 DOI 10.1007/s11245-017-9474-8 What are the Units of Language Evolution? Nathalie Gontier1 Published online: 19 April 2017 © Springer Science+Business Media Dordrecht 2017 Abstract Universal Darwinism provides a methodology I-language Internal language to study the evolution of anatomical form and sociocul- E-language External language tural behavior that centers on defining the units and levels of selection, and it identifies the conditions whereby natu- ral selection operates. In previous work, I have examined 1 Introduction and Outline how this selection-focused evolutionary epistemology may be universalized to include theories that associate with an Language origin and evolution studies face two major prob- extended synthesis. Applied evolutionary epistemology lems (Part 2). Scholars study numerous language-associ- is a metatheoretical framework that understands any and ated phenomena because they disagree on what language all kinds of evolution as phenomena where units evolve is and how it evolved (Sect. 2.1); and at present, no crite- by mechanisms at levels of an ontological hierarchy; and ria exist to choose amongst opposing theories (Sect. 2.2). it provides three heuristics to search for these units, levels Consequently, obtained data and results remain juxtaposed, and mechanisms. The heuristics are applicable to language and a unified theory on language and its evolution remains and sociocultural evolution, and here, we give an in-depth absent. analysis of how the unit-heuristic can be implemented into Here, we circumvent the definitional problem and show language origin and evolution studies. The importance of how applied evolutionary epistemology (AEE) provides a developing hierarchy theories is also more fully explained. uniform methodology for evolutionary linguists (part 3). AEE (Gontier 2010a, b, 2012) is a methodology derived Keywords Applied evolutionary epistemology · from how Universal Darwinists study how evolution occurs Evolutionary linguistics · Units · Levels · Evolutionary by means of natural selection, but it also incorporates theo- mechanisms · Hierarchy theory ries associated with an extended synthesis. AEE defines evolution as the phenomena where units evolve at levels of Abbreviations an ontological hierarchy by mechanisms. LE Language evolution Implementing AEE into evolutionary linguistics, there- EE Evolutionary epistemology fore, involves a systematic search for the units, levels, and AEE Applied evolutionary epistemology evolutionary mechanisms involved in LE (part 4). I intro- SVT Supra-laryngeal vocal tract duce three heuristics whereby we can identify, examine and evaluate all three and I give an in-depth analysis of the unit- heuristic (part 5). I end by pointing out future prospects for research (part 6). For an in-depth analysis of the level- and * Nathalie Gontier mechanism-heuristic, I refer the reader to Gontier (2017). [email protected] 1 Applied Evolutionary Epistemology Lab, Centre for Philosophy of Science, Universidade de Lisboa, Lisbon, Portugal Vol.:(0123456789)1 3 Author's personal copy 236 N. Gontier 2 Two Problems for Evolutionary Linguistics communication as the transfer of a signal/ message/ information between a sender and a receiver. A sig- We first analyze the definitional problem and then exam- nal/ message/ information may refer broadly to emo- ine the methodological problem that confronts evolutionary tions, facial expressions, vocal calls and gestures of linguists. both human and other animals (Darwin 1872), or it may refer specifically to co-verbal gesturing (Goldin-Meadow 2.1 The Definitional Problem 2007) or body language that accompanies modern lan- guage. And although animal communication systems can Evolutionary linguistics today combines data from linguis- be understood narrowly as signals (Maynard Smith 1974; tics, anthropology, primatology, archaeology, neurology, Krebs and Davies 1978), they can also encompass behav- and psychology. Scholars disagree on what language is ioral repertoires that include maternal bonding (Altmann and this impacts how they study its evolution. Some under- 1974) or grooming (Dunbar 1998). Animal communica- stand language as a unique human capacity, others say it tion systems are often species-specific, but they also con- evolved from animal communication systems, and still oth- vey meaning interspecifically (in predator–prey relations, ers assume the existence of an intermediate protolinguistic for example); and Witzany (2014) has recently drawn stage. attention to intra-organismal communication that occurs Bio-linguists define language as an individual and between different bodily organs or between a host and its inborn neurocognitive capacity (Lenneberg 1964). Chom- microbiome. sky (1999) and co-workers (Berwick and Chomsky 2016) Finally, beyond language and communication, a rising divide this faculty of language into three components; the number of scholars today investigate protolanguage. Origi- sensorimotor system that enables language output (speech nally, the term referred to a hypothetical stem obtained or gesturing), the conceptual-intentional system that pro- from comparing manuscripts, or it denoted a hypothetical vides the input for language (thought that underlies the urlanguage acquired from using internal reconstruction lexicon), and the cognitive capacity to merge that enables methods (Schleicher 1861–1862). Today, it also refers to a recursion (that characterizes universal grammar). Merge hypothesized but considered real communicative/linguistic is defined as the basic property of human language, and system used by early modern humans and perhaps other recursion defines the faculty of language in the narrow hominins (Bickerton 1990; Tallerman 2011; Wray 1998). sense (FLN). The other two systems are part of the faculty Scholars thus continue to disagree on the nature of of language in the broad sense (FLB), and components of it (animal) communication, proto-language, and language are shared with other animals (Hauser et al. 2002). The dis- and proposed definitions are often intensional/functional, tinction between the FLN and FLB is a reinterpretation of exclusive, outdated, and incongruent with actual scientific what Chomsky originally called I-(nternal) and E-(xternal) practices. Definitions are intensiona/functional because language. Both the FLB and FLN are recognized to be part they seek to find the essential or functional characteris- of an “organism-internal environment” that they oppose tics of language. They are exclusive because they single to an “external environment” that is divided into “social”, out one phenomenon to the exclusion of all others (e.g. “cultural”, “physical”, and “ecological” layers or realms. the biological capacity versus the sociocultural transmis- With this distinction, they take the hierarchical nature of sion of language versus language as a system). They are reality into account. outdated because some definitions are over 100 years old In humans, the FLB is said to enable a “secondary sys- (e.g. de Saussure’s (1916) language, langue, and parole), tem of communication” (Berwick and Chomsky 2016: and they were often formulated within a non-evolutionary 64), but for Chomsky, language primarily facilitates inter- context (e.g. Shannon–Weaver’s model). Instead, defini- nal thought. E-language is traditionally studied by dia- tions remain based upon classic dichotomies including the chronic linguists, anthropologists and psychologists. These innate-acquired or biological–cultural, animal–human or have shown that, although words might be inventions of continuity–discontinuity, or historical diffusion–biological an individual’s conceptual-intentional system, for these evolution divides. Finally, definitions are incongruent with to become learned by others and integrated into a soci- actual scientific practices because scholars do not study ety’s lexicon, sociocultural interaction and transmission communication, protolanguage or language as monolithic is required. E-language-related phenomena including lan- wholes and from within a specific biological, neurologi- guage acquisition, variation, change, and diffusion there- cal, cultural or linguistic domain. Instead, they realize that fore often require group-level explanations that go beyond the entities referred to are heterogeneous. That is why they I-Language. focus on a wide variety of genetic and anatomical features, (Animal) communication systems are also defined dif- neuro-cognitive capacities, individual and group behavioral ferentially.