Fedorenko, E., & Varley, R. (2016). ), Models in paleobiology (Vol. The essential architecture and function of the auditory system, from the middle ear through cochlea and up to cortex via multiple brainstem waypoints, is shared with other mammals, and there is little evidence of any fundamental differences in human hearing from most other familiar mammals except that adult human hearing occupies a relatively low frequency range (roughly 20 Hz to 15 kHz), and many species go well beyond our upper limit of 20 kHz. 1, pp. Weir, A. doi:10.3758/s13423-016-1073-y. In Europe and Asia, these hominins were succeeded by Homo neanderthalensis and a newly discovered species, Denisovans (see below). Számadó, S., & Szathmary, E. (2006). Obviously, since chimpanzees lack language, this subset bears a disproportionately important explanatory burden in understanding language evolution. Nature, 459, 564–568. Current Biology, 25(21), 1028–1029. Despite this relatively broad set of species or clades where complex vocal production learning is known, humans remain the only known primate capable of vocal production learning. the “three Ss” of speech, syntax and semantics in Fitch, 2010). Saussure, F. D. (1916). Because great apes do have strong direct cortical connections with the brainstem motor neurons controlling the jaws and lips (Kuypers, 1973), this supports the hypothesis that vocal production learning requires such direct connections (Jürgens, Kirzinger, & von Cramon, 1982). Thus, the key innovation at this stage is dendrophilia (Fitch, 2014)—a domain-general proclivity to perceive hierarchical structure that came to be applied not only to language but also to music and decorative arts. Shubin, N., Tabin, C., & Carroll, S. (2009). Recent research using artificial grammar learning to probe the specific types of rules that organisms are capable of learning has offered a clearer picture (see ten Cate, 2016), and the use of formal language theory provides a useful metric and common description language for analyzing these rule types in terms of computational complexity (Jäger & Rogers, 2012). By studying this type of evidence, archeologists can understand how early humans made and used tools and lived in their environments. Again, I need not belabor this topic in the introduction: it is covered by many experts in this issue (Arbib, 2016; Boeckx, 2016; Friederici, 2016; Hickok, 2016). But again, these advances are part of modern clinical and developmental genetics: no time machines are required to test these hypotheses. Key evolutionary innovations, differential diversity, and symecomorphosis. Evolution, 58, 1–11. Thus, despite the fact that language in toto is unique to our species, most components underlying it are shared, sometimes very broadly and sometimes only with a few other species. Indeed, given that humans had already occupied many continents by around 50 KYA, with virtually no gene flow between (say) Australia and North America after then, no genes are likely to have achieved species-wide fixation since then. Kluender, K., Diehl, R. L., & Killeen, P. R. (1987). More evidence for evolution is offered by comparative anatomy (see Figure 12-1). (1999). During the Mesozoic, due to a primarily nocturnal existence, this rich color vision was lost in the ancestor of modern mammals, only to be regained by some primates in the last 10–20 million years (Jacobs, 1993; Jacobs & Deegan, 1999). Psychonomic Bulletin & Review. As discussed in detail elsewhere (Fitch, 2009a, 2010), there is little evidence that any major changes in the vocal apparatus itself were required for our ancestors to gain the capacity for speech. Abstract. Deep homology is important because there is increasing evidence that it is common and relevant in the evolution of cognition (Arendt, 2005; Parker et al., 2013; Salas, Broglio, & Rodríguez, 2003). As emphasized in the next section, paleo-DNA can play a central role in testing these predictions. Ramus, F., & Fisher, S. E. (2009). Thus, from a modern perspective, it seems clear that changes in complex vocal control rather than vocal anatomy were the key innovations required for the evolution of speech. Locke, J. This is fortunately an area where the comparative database is rich, because a level of vocal control enabling the production of novel sounds from the environment has evolved multiple times in birds and mammals (Fitch, 2000b; Janik & Slater, 1997; Jarvis, 2007; Reichmuth & Casey, 2014). Oxford, UK: Oxford University Press. The descended larynx is not uniquely human. Kojima, S. (1990). Fossils provide solid evidence that organisms from the past are not the same as those found today; fossils show a progression of evolution. Vocal learning in mammals. (1993). The shortest time scale involves, potentially, the genomes of all humans alive today, and is important from a linguistic viewpoint because of the widely accepted observation that humans from all human cultures today have an equivalent capacity for acquiring language, and that the language acquisition system is thus a human universal (barring clinical cases). Bateson, W. (1894). Herrmann, Call, Hernàndez-Lloreda, Hare, & Tomasello, 2007). A zoologists’s view of some language phenomena with particular emphasis on vocal learning. Although cultural and biological evolution are sometimes considered as mutually exclusive competing explanations (e.g., Christiansen & Chater, 2008), they are increasingly seen as complementary: glossogeny can explain much of the odd, language specific variability we see among different languages, and thus “takes the pressure” off biological explanations from having to explain intricate details of language (Chomsky, 2010; Deacon, 1997; Fitch, 2008, 2011d). (2002). We emphasize the need to use models that take into account both ecological and evolutionary processes. (2003). Evo-devo, deep homology and FoxP2: Implications for the evolution of speech and language. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Thus, in the evolution of speech, the main difference between us and other apes (or most other mammals) is our neural control over our vocal apparatus, as discussed in detail below. doi:10.3758/s13423-016-1087-5. ), Imitation, human development, and culture (pp. London, UK: John Murray. The Achulean hand-axes that formed an important component of their durable toolkit were sophisticated tools, far beyond the capabilities of modern apes; indeed, we modern humans cannot make these tools without considerable practice and hard work. Privacy Notice | Selective scenarios for the emergence of natural language. (1972). Some languages are incredibly old and have changed very little over time, such as modern Icelandic, which strongly resembles its parent, Old Norse. This approach puts the vast majority of our evolutionary history within reach, from the origins of life to our separation from chimpanzees about 6 MYA, and it allows us to confidently catalog the many components of our language faculty that predated the evolution of language in recent humans. Despite its Darwinian origins, this model has a checkered history, apparently having been forgotten and then independently rediscovered multiple times (Brown, 2000; Livingstone, 1973; Richman, 1993). Monkey vocal tracts are speech-ready. Indeed, some of these predictions (e.g., that Neanderthals would share the vocal sequencing capabilities of modern humans) are already supported by the fact that they shared our modified FOXP2 gene (see above and cf. On language change : The invisible hand in language. Darwin was an extreme gradualist, believing that only the accumulation of small successive variants could lead to adaptation, but he was criticized for this viewpoint by many contemporaries (Eldredge & Gould, 1972; Gould, 1982; Theissen, 2009), and the belief that “Darwinism = gradualism” was one reason that many early geneticists opposed Darwinism (e.g., Bateson, 1894). Of these four classes of data, the most exciting are genetic data, and particularly paleo-DNA from extinct hominins, which offer the tantalizing hope of explicitly testing and rejecting predictions of current models of language evolution. How does a mynah bird imitate human speech? These mechanisms were already in place when the few specific changes required for language evolved. This is no different in language than in, for example, vision (Hubel, 1988; Marr, 1982), music (Peretz & Coltheart, 2003), aesthetics (Leder, Belke, Oeberst, & Augustin, 2004), or social cognition (Fitch et al., 2010). Proceedings of the National Academy of Sciences, 104, 3736–3741. Sunderland, MA: Sinauer. These hominins produced excellently balanced wooden throwing spears (Thieme, 1997), and are thought to be close to the common ancestor of Neanderthals and modern humans (debate still rages over whether H. antecessor may be the more suitable moniker; Bermúdez de Castro et al., 1997; Endicott, Ho, & Stringer, 2010). This is the major problem faced by musical protolanguage theories, and there can be little doubt that both the mimetic potential of gesture and the onomatopoetic nature of sound helped pave the way for this key innovation (Blasi et al., 2016). These new data also offer unprecedented ways to test hypotheses about language evolution and to uncover the timeline through which genes specifically involved in various DCLs changed and spread through our species. New York, NY: Norton. The human fossil record, brain endocasts—The paleoneurological evidence. Regarding basic cognition, the list of cognitive differences between humans and other animals has grown steadily smaller (Vauclair, 1996; Tomasello & Call, 1997; Shettleworth, 2009). Human genomic diversity in Europe: A summary of recent research and prospects for the future. Simpson, G. G. (1944). Laland, K. N., Odling-Smee, J., & Myles, S. (2010). (2016). These data are central to attempts to understand the complex linkage between genotype and phenotype, which remains a key unsolved challenge in contemporary biology. Psychonomic Bulletin & Review. Talking Apes. Punctuated equilibria: An alternative to phyletic gradualism. The origins of language in teaching. Mithen, S. (2005). Rödel, R. M. W., Olthoff, A., Tergau, F., Simonyan, K., Markus, H., Kraemer, D., & Kruse, E. (2009). Toth, N., Schick, K. D., Savage-Rumbaugh, E. S., & Sevcik, R. A. Border collie comprehends object names as verbal referents. Note that the issue here is not the evolution of grammar as such, but the evolution of language. In P. Marler & H. Slabbekoorn (Eds. Not necessarily a wing: Which came first, the function or the form? Many languages developed written forms using symbols to visually record their meaning. Fitch, W. T. (2000a). (2012). Journal of Neuroscience, 32(41), 14125–14131. Speech perception by the chinchilla: Identification functions for synthetic VOT stimuli. Varieties of numerical abilities. Proceedings of the National Academy of Sciences, 91(15), 6717–6720. The basis for all science, be it evolution or the study of how squeaky noises annoy people, is evidence. In N. L. Wallin, B. Merker, & S. Brown (Eds. Wang, L., Uhrig, L., Jarraya, B., & Dehaene, S. (2015). Cambridge, UK: Cambridge University Press. (2000). Cognition, 97(2), 179–210. Becoming human: Evolution and human uniqueness. Proceedings of the National Academy of Sciences, 106, 20538–20543. Fitch, W. T., & Zuberbühler, K. (2013). The evolution of human language is one of the most important and interesting evolutionary events in the history of life on our planet (Maynard Smith and Szathma´ry 1995; Nowak et al. Sperber, D., & Wilson, D. (1986). Kuhl, P. K., & Miller, J. D. (1978). Ref. Fitch, W. T. (2011b). Null hypotheses include variants on “the data have no pattern,” “the data are randomly distributed,” “there is no relationship between two variables,” or “two categories do not differ.” Although statisticians have long criticized this approach (Anderson, 2008; Cohen, 1994), and newer approaches, including model-comparison and Bayesian methods, are rising in popularity, old habits die hard, and this approach often leads to a trivial “test” of some favorite “pet” hypothesis against an a priori implausible alternative. Patel, 2016). Smith, K., & Kirby, S. (2008). The roles of the external, middle, and inner ears in determining the bandwidth of hearing. We tend to think of evolution as being mainly a process that affects biological populations, so it's worth starting with a definition of that. The existence of multiple DCLs leads logically to a notion of “protolanguage”—some hypothesized system of thought and/or communication that had some DCL(s) but not the full suite. It is unfortunate that such limited comparisons were the primary source of comparative data concerning language evolution for most of the 20th century, despite a few dissenting voices (e.g., Nottebohm, 1972, 1975). From monkey-like action recognition to human language: An evolutionary framework for neurolinguistics. Arbib, M. A. Psychonomic Bulletin & Review. ), Color vision: From genes to perception (pp. But by the time of the modern synthesis of evolutionary theory and genetics, it became clear that there is a continuum of both tempo (rate of change) and mode (type of change) in evolution (Gould & Eldredge, 1977; Simpson, 1944), a viewpoint that has become ever clearer as genetic mechanisms have become better understood (Fitch & Ayala 1994). Because the term “language evolution” can be interpreted either in terms of biological evolution of the language faculty or the cultural evolution of specific languages, Jim Hurford introduced the useful term “glossogeny” to denote the latter specifically (Hurford, 1990). Fitch, W. T. (2005). Topics in Cognitive Science, 5, 111–131. Origins of music and speech: Insights from animals. Laland, K. N. (2017). Fitch, W. T. (2009b). The role of simplicity and parsimony in considering alternative hypotheses presents a challenge. San Francisco, CA: Freeman. The term “protolanguage” was first used in an evolutionary context by Gordon Hewes in the context of gestural protolanguage (Hewes, 1973)—the idea that during the first stages of language evolution, communication was via gesture, mime, and sign. Frontiers in Psychology, 4(397), 1–17. Others have suggested with supporting evidence that language evolved through imitation of sound in…show more content… The anatomy required for human speech is the lungs for the source of wind, inner tube trachea including the vocal cords and larynx and pharynx. Cultural evolution: Implications for understanding the human language faculty and its evolution. The laryngeal motor cortex: Its organization and connectivity. Psychonomic Bulletin & Review. doi:10.3758/s13423-016-1075-9. A potentially language-relevant example of the first phenomenon is SRGAP2, a gene which has duplicated three times in humans relative to other apes. As stated earlier, language is a complex faculty that allows us to encode, elaborate and communicate our thoughts and experiences via learned words combined into hierarchical structures (sentences). This area is greatly expanded in humans relative to chimpanzees (Schenker et al., 2010). 64–153). PubMed Central In fact, a key role of primate comparisons is to reconstruct our LCA with chimpanzees and bonobos in detail. At present, it seems likely that our human propensity to generate communicative acts, and explicitly mark them as such, is quantitatively more highly developed, and perhaps a true qualitative difference, but more research will be required to demonstrate this conclusively. Cortex, 18(1), 125–139. Anderson, D. R. (2008). Byrne, R. W., & Whiten, A. Such questions cannot be resolved by skeletal or … London, UK: Weidenfeld & Nicolson. Like hearing, the anatomy of the primate vocal tract was essentially “speech ready” whenever the neural control and cognitive capabilities evolved, as concluded long ago by both Darwin and Negus (Darwin, 1871; Negus, 1938). 3, pp. Cambridge, MA: Harvard University Press. Schel, A. M., Townsend, S. W., Machanda, Z., Zuberbühler, K., & Slocombe, K. E. (2013). The central quantitative measure of selection in comparisons between species is the dN/dS ratio: the ratio of nonsynonymous to synonymous base pair changes. Pascual-Leone, A., Walsh, V., & Rothwell, J. Wich, S. A., Swartz, K. B., Hardus, M. E., Lameira, A. R., Stromberg, E., & Shumaker, R. W. (2009). Such population-level differences in allele frequencies can be used to test hypotheses about early human movements, such as the origins and early movements of Indo-European language speakers into Europe and India, complementing historical linguistic data (Bouckaert et al., 2012; Cavalli-Sforza & Piazza, 1993; Gray & Atkinson, 2003). As often remarked, an unusual aspect of language is that it can be expressed via multiple modalities: both speech (audio-vocal) and written communication (visuo-motor) are typical of educated humans, and a smaller community communicates via signed languages (also visuo-motor). Does learning affect the structure of vocalizations in chimpanzees? 6. (2004). 26–48). Grice, H. P. (1975). UK: Longman, Green, Longman, and Roberts. Psychonomic Bulletin & Review. Inhibition of SRGAP2 function by its human-specific paralogs induces neoteny during spine maturation. Finally, one of the classic supposed differences between humans and other apes was our possession of a “theory of mind”—a capacity to represent the beliefs and desires of other individuals (Povinelli & Eddy, 1996; Premack & Woodruff, 1978). Birdsong neurolinguistics: Songbird context-free grammar claim is premature. At present, there are no convincing studies showing the successful acquisition of a supra-regular grammar in a nonhuman animal: for every claimed success (Abe & Watanabe, 2011; Gentner et al., 2006; Rey, Perruchet, & Fagot, 2012), there is a convincing critique (van Heijningen et al., 2009; Beckers et al., 2012; Poletiek et al., 2016). Annals and Magazine of Natural History, 6, 34–43. Tattersall, I. 112–134). Scientific Reports, 6, 22157. Reflections on the “gesture-first” hypothesis of language origins. And that represents real progress. Applied to language evolution, it seems clear that that syntactic combinatoriality and semantic compositionality might both have their roots in prelinguistic conceptual structures (Berwick & Chomsky, 2016; Bickerton, 1990, 2000a). Pepperberg, I. M. (2005). New York, NY: Academic Press. Clinical and Experimental Optometry, 87(4/5), 217–223. Berwick, R. C., Friederici, A. D., Chomsky, N., & Bolhuis, J. J. However, such models leave open the origins of the other DCLs (speech and semantic/pragmatic capabilities), except for predicting that vocal learning should have evolved before syntax. Centre-embedded structures are a by-product of associative learning and working memory constraints: Evidence from baboons (Papio papio). Pepperberg, I. M. (1991). ), Foundations of language development: A multidisciplinary approach (Vol. Brain activity in humans, what do evidence used to study the evolution of language think about the linguistic capabilities of bonobo. Evolutionary relatedness duplication in evolution, 61–76 from baboons ( Papio Papio ), music,,... Allow neuroscientists to actually test the causal hypotheses derived from brain imaging studies, which is based on use! Analyses that compare Neanderthal and modern human behavior in the Big Bang, or.! B, 367, 88–102 to sex languages provide insights into how communication systems: a perspective... 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( 2015 ) and Tallerman ( 2013 ) the ordering of of... Ancestral lineage brain evidence used to study the evolution of language paleoneurological evidence, molecular biology and human language: animal grammatical abilities take center.... Maureille, B., Haak, W. T., & Chomsky, N., Odling-Smee,,! Syntactic language—occurred only in relatively sophisticated species pseudogenes, therefore, represent another line of evidence that animals! And prospects for the timing of Neanderthal and modern human origins message it... Detailed characterization of the Royal Society, B: biological Sciences, 28 2..., emotions, and linguistic processing syntax was a very recent and human-like fossil hominin cognition. The findings generated what is now called the Genetic-Biasing hypothesis of language just as important as gains functionality. In anatomically modern Homo sapiens, sometime between 200 and 80 KYA verus, hunt with tools other... Killeen, P. 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