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Lecture 9 Controversies and hypotheses 1 3. What is language (again!)? When language evolved? How it evolved? 4. Why it evolved? 5. Can language evolution be divided in “stages”? Which? (Lecture 11) 1. 2. (Lecture 9) (Lecture 10) 2 Aristotle Man: the rational – and linguistic – animal Condillac (1746) Action > gesture (through ritualization = non- normative conventionalization) Iconicity in gesture/pantomime > grammar Rousseau (1781) Gestures and cries > language (through rituals and songs), “the social contract” 3 Monboddo (1774) “four original types of communicative self- explanatory signs: facial expressions, painting, emotional cries, imitative iconic signs ” (Johansson 2005: 15) Herder (1772) “our generalist minds and lack of instincts” (ibid: 160) Mueller (1866: 354) “Language is our Rubicon, and no brute will dare cross it.” 4 Chomsky (1988: 167) “In the case of such systems as language and wings (sic!) it is not easy even to imagine a course of selection that might have given rise to them.” Pinker and Bloom (1990) “Natural language and natural selection” Fitch (2002: 162) “the scientific study of the evolution of language has apparently come of age” 5 1. 2. 3. 4. 5. Innate/genetically determined vs. Learned/culturally determined Adaptation vs. Spandrel (+ Exaptation) Early vs. Late (< 100 000 YA) origin Gradual vs. Abrupt Speech-first vs. Gesture-first “The dimensions should not be interpreted as eitheror dichotomies, but as continua (?), along which different hypotheses can be located at different points” (: 163) Evidence presented so far (and more) provides “constraints on hypotheses” (see Chapter 12) 6 Not so much concerned with language evolution per se, but with “what is language” (mainly): Formal or functional system? Modular or cognitive (integrated)? Biological or cultural? “System” or “usage” (know-how, contingencies) Richest domain of research in terms of evidence 7 “I have no idea what the phrase [i.e. innateness hypothesis] is supposed to mean and have correspondingly never advocated any such hypothesis – beyond the truism that there is some language-relevant distinction between granddaughter and her pet kitten” (Chomsky 1999, Johansson: 178) The questions are what is the “distinction”? is it language-specific? 8 1. 2. 3. The universality of linguistic features, e.g. hierarchical structure, “nouns and verbs” “The poverty of the stimulus” – impossibility of language acquisition without a priori knowledge of “Universal Grammar”, no “learning algorithm” (Universal) patterns in L1 acquisition, e.g. few overgeneralizations, *”I sent Malmö a package” 9 Linguistic universals Can be questioned, e.g. recursion in general, and for a given language such as Piraha (Everett 2005) or Riau Indonesian (Gil 2001) Evans and Levinson (2010): “The myth of linguistic universals” (BBS, target article) Can be explained by other means: ▪ Features of cognition and/or reality (Cognitive Linguistics) ▪ “Adaptive pressures” from communication and learning (Functional Linguistics) ▪ Descent from a common original language ▪ Necessary “semiotic constraints” (Deacon 2003) 10 Is the “stimulus” really “impoverished”, and is acquisition free of overgeneralizations? “Motherese”- possibly universal “Negative evidence” available without explicit correction (cf. the situation in vocabulary learning) What children acquire is not a Chomsky-style generative grammar, but e.g. “the performance system underlying comprehension and production” (Seidenberg & MacDonald 1999) Children do make all kinds of errors in L1 - but “recover” quickly. 11 The timing of monolingual and bilingual language acquisition No major differences, which would be expected if UG was innate (t = 0) Alternative theories of L1 acquisition (e.g. Tomasello 2003) “The poverty of the genes” Less than 20 000 genes for entire human body and brain! 12 Brain plasticity, especially on the global level (and language is not a “module”) Long periods of group-living (and interbreeding) does not lead to innate biases for learning the group’s language “Ape-language” studies (and maybe even those with dolphins and grey parrots) have met with some degree of success 13 “Strong claims of a complex and fully genetically determined innate grammar are untenable” (Johansson 2005: 188) This does not imply that language can be “learned” by “a general learning device” (or a kitten with a larger brain) Even if language is essentially a cultural phenomenon, there is good evidence for “gene-culture co-evolution” (at least for speech) 14 Spandrel is a term used in evolutionary biology describing a phenotypic characteristic that is considered to have developed during evolution as a side-effect of an adaptation, rather than arising from natural selection. The term developed from an analogy of causal relationships between forms found in architecture and those found in biology. The term was coined by the Harvard paleontologist Stephen Jay Gould and population geneticist Richard Lewontin in their influential paper "The Spandrels of San Marco and the Panglossian Paradigm: A Critique of the Adaptationist Programme" (1979). (Wikipedia) 15 16 “Evolutionary theory offers clear criteria for when a trait should be attributed to natural selection: complex design for some function, and the absence of alternative processes capable of explaining such complexity. Human language meets this criterion…” (Pinker and Bloom 1990: 707) Jackendoff and Pinker (2005) vs. Hauser, Chomsky and Fitch (2002) FOXP2 was selected for in the hominine line 17 C. Johansson: cultural evolution on a “preexisting biological substrate” may be sufficient Tomasello (1999): 5 million years, and minimal (?) genetic differences from the chimpanzees are not sufficient for a “tool kit” of adaptations Lightfoot (2000) Some linguistic rules are not obviously functional, e.g. “subjacency” *Whose paper that I read on the train is”? It is not clear that FOXP2 is a “language gene” 18 Not either-or: Some features of language can be adaptations and other spandrels, or both (starting as spandrels, or as exaptations) “The first steps towards language had to be based on pre-existing features that had originally evolved form some other purpose” (: 164) Some “final steps” may be the result of cultural evolution: language adapting to us, rather than vice versa 19 “Late hypotheses with biological based language faculties are severely constrained” (: 167), i.e. implausible! Since there were adaptations for speech in the Neanderthals, these go back at least to the common ancestor (800,000 YA). “The Upper Paleolithic revolution” of 40,000 YA: “The revolution that wasn’t” (McBreasty and Brooks 2000) => Support for relatively early origins 20 Language as a cultural “invention”, and not determined by the genetic/biological bases (which must then be explained as exaptations for non-linguistic functions) The early material culture of Homo sapiens (about 200,000 YA) was not truly “symbolic” (Davidson 2003) The Singing Neanderthals (Mithen 2005): “their communication system would be holistic, multi-modal, manipulative and musical: Hmmm” Possible, but hardly the “best explanation” 21 Geologically sudden ≠ “sudden on human timescales” (speciation in a single generation) “… the punctuations of punctuated equilibrium do not represent de Vresian saltations, but rather denote the proper scaling of ordinary speciation into geological time” (Gould 2002: 19) “the sudden single-step evolution of something as complex as language is highly problematic” (Johansson 2005: 170) 22 Sudden: Language is so unlike animal communication Gradual: This does not imply that “gulf” was bridged in a single step Sudden : Mutation in “master regulatory genes” (Schwartz 1999) Gradual: “genuinely new features require changes in the developmental programs themselves, not just in the master switches” (Johansson 2005: 171) 23 Sudden: FOXP2 is one such regulatory gene, and seems to play some role for language Gradual : But (a) the relevant mutations seems to have been present in Neanderthals and (b) they do not concern only language and (c) FOXP2 “problems” do not affect language capacity as a whole Sudden: Universal Grammar is “monolithic” Gradual : Not even Chomsky holds this anymore 24 “If biological evolution dominated the process, as it would have to, if language is innate in any strong sense, then the process can be expected to be geologically slow. On the other hand, if language is largely the product of memetic [rather: cultural] evolution, then even a gradual process may appear geologically sudden” (Johansson 2005: 173) 25 “I cannot doubt that language owes it origin to the imitation and modification, aided by signs and gestures, of the various sounds, the voices of other animals, and man’s own distinctive cries” (Darwin 1872: 56) The homology between animal vocal signals and language is far from unproblematic. 26 1. 2. 3. 4. 5. 6. Paleontology and archeology Neuroscience Comparative psychology Developmental psychology Gesture studies Semiotic analysis 27 H. Ergaster/Erectus had tool manufacture, migration, camps, fire… – but not the only (?) fossilizing marker that is still plausibly connected with speech: an extended thoracic canal, for controlling breathing (MacLarnon & Hewitt 1999, 2004) Control of breathing is also necessary for sustained running, or singing. (Fitch 2009) 28 An extension of control for bodily mimesis to “vocomimesis” and eventually phonology (Zlatev 2008b) BA 44, 45 = Broca BA 22, 39, 40 = Wernicke Overlap extensively with the “human mirror neuron system” (Arbib 2005; Iacoboni 2005; Decety & Chaminande 2005): in tasks of perception-action matching, imitation, imagination, pantomime… BA 4, 6 = perceptionproduction of “meaningless syllables” (Wilson et al. 2004) 29 “…primate gestures are individually learned and flexibly produced communicative acts…vocal displays are mostly unlearned, genetically fixed, emotionally urgent, involuntary, inflexible… They are broadcast mostly indiscriminately…” (Tomasello 2008: 54) Chimpanzee calls are of two types: “broadcast” and “proximal”, and the two lead to distinct brain-activation patterns (Taglialatela et al. 2008) 30 Cultural comparsion: Main semiotic categories (whole corpus, components per utterance) 0,7 0,6 0,5 0,4 0,3 0,2 0,1 0 Developmental primacy of iconic and pointing gestures compared to speech (Bates 1979; Tomasello 2008; Zlatev and Andrén 2009) The epigenetic character of development can be used as an argument for analogy with evolution without appealing to “recapitulation” (Zlatev 2003) Speech and gesture development are closely linked in time (Goldin-Meadow 2003; Andrén 2010) Analogy between evolution and development is always “controversial” Sw e Thai Deictic Iconic (Zlatev and Andrén 2009) Emblematic 31 The ubiquity and universality of gestures – which even when conventional are never completely arbitrary. Gestures and speech are closely related - but “single system”? (McNeil 2005) Even the most “transparent” gestures are in part conventional (Streeck 2009; Andrén 2010) 32 “Several different lines of evidence, then, can be added up to support the hypothesis that the first step in the evolution towards linguistic expression was taken with the employment of visible action, or gesture, for referential expression. Yet, as has often been pointed out, this seemingly attractive hypothesis faces, as MacNeilage (1998: 232) has put it, an insuperable problem. Languages are overwhelmingly spoken.” (Kendon 2008: 12) 33 After chimps and dolphins, perhaps other social species (elephants, buffalo) will be found to have diverse vocal calls – but these are still signals and not symbols before being shown to involve a referential triangle. Many reasons to select for speech, after triadic mimesis (economy, non-visibility, parallel use…), and furthermore: mimesis is not a full “gestural language” Even today, there is no “absolute switch”, but a “gesture-speech integrated system”, and language can emerge in the gestural modality whenever speech is “blocked” (deafness). 34 Learned vs. innate: mostly learned, but with at least some biological adaptations Adapation vs. exaptation/spandrel: both Early vs. late: early adaptations, possibly late cultural evolution Gradual vs. sudden: gradual, but apparently “step-wise”, punctuated Speech-first vs. gesture-first: controversial… 35