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Chapter 54: Biology, Genetics and Evolution Antonio Benítez-Burraco1

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Chapter 54: Biology, Genetics and Evolution Antonio Benítez-Burraco1 Chapter 54: Biology, Genetics and Evolution Antonio Benítez-Burraco1, Koji Fujita2, Koji Hoshi3 and Ljiljana Progovac4 1. Department of Spanish, Linguistics and Theory of Literature (Linguistics), Faculty of Philology, University of Seville, Seville, Spain 2. Department of Human Coexistence, Graduate School of Human and Environmental Studies, Kyoto University, Kyoto, Japan 3. Faculty of Economics, Keio University, Yokohama, Japan 4. Department of English, Linguistics Program, Wayne State University, Detroit, USA Overview 1. Introduction 2. The core view: Biolinguistics and the Chomskyan approach to language evolution 3. The brain 4. Genetics 5. Subsequent views/developments 5.1. Gradualist view within Minimalism 5.2. Neurobiological continuity under Minimalism 5.3. Evolutionary continuity under Minimalism 6. Future prospects 1. Introduction In this Chapter we first look at the core view of the biology of language associated with Minimalism, including the Biolinguistics Program (section 2). Next, we consider research on the brain (section 3) and genetics (section 4), associated with this framework. Finally, we introduce some subsequent views of language evolution which break away from the saltationist, 1 discontinuous nature of the mainstream approach (section 5), and draw some conclusions regarding future prospects (section 6). 2. The core view: Biolinguistics and the Chomskyan approach to language evolution Rather than a thorough introduction, here we can only provide a brief perspective on the Biolinguistics Program, associated with linguist Noam Chomsky. The very term Biolinguistics in the modern sense is linked to the events that started in the 1950’s, with the early work of Noam Chomsky (e.g. his Ph.D. manuscript The Logical Structure of Linguistic Theory, 1955), and Eric Lenneberg’s influential (1967) book, Biological Foundations of Language, which popularized the idea of the critical period in language acquisition (for some discussion, see e.g. Hoshi 2017). This kind of approach that studies language in a biological framework saw a revival at the turn of the 21st century, when it picked up pace significantly, with its own dedicated journal, Biolinguistics, as well as hundreds of publications addressing the topic, including several co- edited volumes. In the editorial introduction to their newly established journal Biolinguistics, biolinguists Cedric Boeckx and Kleanthes Grohmann adopt the following five main topics of inquiry for this enterprise (Boeckx and Grohmann 2007), posed already in the early days (see Chomsky 1986, 1988): (1) 1. What is knowledge of language? 2. How is that knowledge acquired? 3. How is that knowledge put to use? 4. How is that knowledge implemented in the brain? 5. How did that knowledge emerge in our species? The charge of this chapter is to address the last two questions, i.e., how language is represented in the brain, and how it evolved in our species, from the point of view of Minimalism. On the face of it, the term Biolinguistics evokes a field that studies language in a biological framework, considering how to cross-fertilize crucial postulates and findings in biological sciences with those of linguistic sciences. However, the term has been used somewhat differently and more narrowly, to refer to a rather specific approach to the nature of the faculty of language, in particular a specific theoretical approach to syntax, leading to a focus that is perhaps unexpected. 2 First, Biolinguistics is not primarily or necessarily associated with biology, but is instead associated more broadly with the ‘laws of nature,’ often invoking physics or mathematics (see e.g. Lenneberg, 1972, who warned against this trend in generative grammar). For example, it is often considered in this approach that the essence of syntax is better illuminated by regular and orderly principles of nature, such as those postulated in physics and mathematics, rather than biological postulates such as natural selection and evolutionary tinkering (see e.g. Jacob 1977 for the relevance of tinkering in biological, adaptationist approaches to evolution). It has been Noam Chomsky’s long-held view that invoking natural selection via tinkering can be symptomatic of the lack of understanding: “if you take a look at anything that you don’t understand, it’s going to look like tinkering,” but when things are properly understood, one realizes that there is much more order in nature (Chomsky 2002, p. 139). Chomsky (2002, 2005), among others, has claimed that human language/grammar can be a by- product of other phenomena, such as the increase in brain size, or general laws of physics, rather than being an agent in its own evolution (see e.g. the quote from Berwick and Chomsky 2011 below, according to which “language is something like a snowflake, assuming its particular form by virtue of laws of nature…”.1 This stands in stark contrast to the arguments put forth by e.g. Pinker and Bloom (1990), who state that the only way to evolve a truly complex design that serves a particular purpose, such as language, is through a sequence of mutations/changes with small effects, and with intermediate stages (but see e.g. Lewontin, 1998, for a criticism of such views). Pinker and Bloom’s argument is based on the analogy with the intricate structure of the eye, stating that evolution is the only physical process that can create an eye because it is the only physical process in which the criterion of being good at seeing can play a causal role. On the other hand, Noam Chomsky’s arguments have to do with (i) his view that syntax is an all or nothing package, not decomposable into stages (the view which seems to be shared by many other followers of Biolinguistics2), as well as with (ii) his long-held view that there are no 1 These claims can be related to e.g. Thompson-style (1917) view that physical laws are part of biology, in the sense that biological forms can be determined by physical/mathematical laws, and according to which natural selection is considered to be only of secondary importance. 2 This view of syntax and its evolution can be found in e.g.: Berwick (1998); Bickerton (1990, 1998); Lightfoot (1991); Chomsky (2002, 2005); Berwick and Chomsky (2011; 2016); Piattelli-Palmarini (2010); Piattelli-Palmarini and Uriagereka (2004; 2011); Moro (2008); Hornstein (2009); Miyagawa (2017); Miyagawa et al. (2014); Di Sciullo (2013). 3 genetic differences among humans when it comes to language abilities (e.g. Chomsky 2002: 147; Berwick and Chomsky 2016). In their (2016) book Berwick and Chomsky did conclude that natural selection may have been responsible for spreading that one beneficial mutation that they postulate was responsible for the emergence of language (see below), but this was only after a bulk of the book discussed what they consider to be the problems with natural selection, and the problems with Darwin not having had a mathematical mind. Moreover, invoking selection for one single mutation is very different from invoking it at multiple steps in the evolution of a trait, as has been the case with e.g. the structure of the eye, involving intermediate stages and tinkering with its many interacting components, where each step brings some (small) benefits, and reveals continuity with the other species. Nonetheless, Berwick and Chomsky’s (2016) claims are consistent with Chomsky’s early views (e.g. 1972, 97) expressed in the context of language evolution that “it is perfectly safe to attribute this development to ‘natural selection,’ so long as we realize that there is no substance to this assertion, that it amounts to nothing more than a belief that there is some naturalistic explanation for these phenomena.” These considerations seem to be unexpected features of the Biolinguistics enterprise, considering its name. Even when this approach invokes biology, it typically expresses opposition to the postulates of natural and sexual selection, as well as to gradualist, adaptationist approaches to the evolution of syntax/language, which are widely utilized in biology. Instead, Biolinguistics is primarily associated with Noam Chomsky and his followers’ view of syntax, which is based on the assumption of the innateness and universality of syntactic/linguistic principles across all humans, and which advocates that this innate capacity was a result of one single evolutionary event, perhaps a slight re-wiring of the brain due to a single minor mutation (see below). As such, this view is saltationist in nature,3 with a rather late postulated date of emergence of language, in humans only, advocating discontinuity between humans and other species, including our closest relatives among the primate group.4 The reason and rationale for the saltationist view seemingly comes from the postulates of the Minimalist Program (although see e.g. Clark 2013 3 This kind of saltationist view of language evolution has been challenged by e.g. Pinker and Bloom (1990); Newmeyer (1991, 1998, 2005); Jackendoff (1999, 2002); Givón (e.g. 2002; 2009); Gil (2005); Culicover and Jackendoff (2005); Tallerman (2014); Heine and Kuteva (2007); Hurford (2007, 2012); Dediu and Ladd (2007); Dediu and Levinson (2013); Progovac (2008, 2010, 2015, 2016a, 2019); Fitch (2017a,b); Fisher (2017). 4 for explaining why the theoretical framework need not determine whether a saltationist or gradualist approach is adopted; see also section 5). According to Berwick and Chomsky (2011: 29-31) “the simplest assumption, hence the one we adopt…, is that the generative procedure emerged suddenly as the result of a minor mutation. In that case we would expect the generative procedure to be very simple… The generative process is optimal. … Language is something like a snowflake, assuming its particular form by virtue of laws of nature… Optimally, recursion can be reduced to Merge… There is no room in this picture for any precursors to language—say a language-like system with only short sentences” (see also Chomsky 2002, 2005).5 While Biolinguistics in this general sense has been around since the 1950’s, it was not until the advent of Minimalism in the 1990’s (e.g.
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