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Linguistics From an Evolutionary Point of View
... Una evidencia de ello se encuentra en las frecuentes menciones positivas a algunos aspectos del modelo de Hockett en la literatura especializada reciente (Cf. Fitch 2011;Slocombe, Waller y Kiebal 2011;Christiansen y Winter 2012;Hurford 2012;Kendon 2014;Collier et al. 2018, entre muchos otros). Siguiendo el hilo de algunas interesantes cuestiones historiográficas, mi intención es, sin embargo, filosófica: evaluar los méritos y las limitaciones de esta propuesta, en tanto fue adoptada de manera generalizada como modelo teórico, o al menos, como la "visión por defecto", tanto en los estudios sobre evolución del lenguaje como en los estudios comparados de la comunicación humana y animal (Wacewicz y Zywiczyúski 2015). ...
... Dos grandes tradiciones dominaron la escena de la lingüística en el siglo pasado: el estructuralismo saussuriano, en la primera mitad del siglo, y el generativismo chomskiano, a partir de la segunda mitad. Más allá de sus importantes diferencias, ambas identificaron como su objeto de estudio a una cierta estructura: la langue y no la parole, y la competence y no la performance, respectivamente (Hurford 2012;Peregrin 2012). Distinguieron, por un lado, la formalización de la estructura fonológica, morfológica y/o sintáctica, y por el otro, el código lingüístico (Perniss 2018), ambos estudiados en una dimensión sincrónica (Anderson 2016) o "procesualmente neutral" (Straight 1993: 208). ...
... Hockett está más cerca de Chomsky en este punto. Sin embargo, el enfoque "biolingüístico" chomskiano no se condice con el aislamiento que la teoría mantuvo respecto de las investigaciones interdisciplinarias sobre los orígenes evolutivos del lenguaje (Hurford 2012), un reproche que no cabe hacerle a Hockett. 3 Como se verá más adelante, según mi opinión, la posición de Hockett es más adecuada que la de Chomsky en diversos puntos. ...
Los estudios comparados del lenguaje humano y los sistemas de comunicación animal, así como el campo de investigación sobre la evolución del lenguaje, estimularon una reflexión específica acerca de los rasgos distintivos del lenguaje humano. Me propongo examinar el modelo de los rasgos de diseño propuesto por Charles Hockett, cuya influencia en las dos áreas mencionadas ha sido notable. Mi objetivo es poner en evidencia cómo los presupuestos en los que se asienta: la preeminencia de la estructura sobre la función y de los rasgos del código sobre las habilidades cognitivas de sus usuarios, comunes a otros enfoques formales dominantes en la lingüística, lo convierten en una herramienta teóricamente ineficaz para ambas áreas de investigación. En particular, objetaré el papel que asigna a los dos primeros rasgos de diseño: el canal vocal-auditivo y la arbitrariedad. Finalmente, lo contrastaré con los enfoques basados en el uso, asentados en los presupuestos contrarios. Estos enfoques caracterizan al lenguaje como un “mosaico” de habilidades cognitivas, individuales y sociales, que se manifiestan en una variedad de vehículos y modalidades, por lo cual proporcionan herramientas teóricas más adecuadas para explicar la evolución del lenguaje así como sus diferencias y semejanzas con los sistemas de comunicación animal.
... Una evidencia de ello se encuentra en las frecuentes menciones positivas a algunos aspectos del modelo de Hockett en la literatura especializada reciente (Cf. Fitch 2011;Slocombe, Waller y Kiebal 2011;Christiansen y Winter 2012;Hurford 2012;Kendon 2014;Collier et al. 2018, entre muchos otros). Siguiendo el hilo de algunas interesantes cuestiones historiográficas, mi intención es, sin embargo, filosófica: evaluar los méritos y las limitaciones de esta propuesta, en tanto fue adoptada de manera generalizada como modelo teórico, o al menos, como la "visión por defecto", tanto en los estudios sobre evolución del lenguaje como en los estudios comparados de la comunicación humana y animal (Wacewicz y Zywiczyúski 2015). ...
... Dos grandes tradiciones dominaron la escena de la lingüística en el siglo pasado: el estructuralismo saussuriano, en la primera mitad del siglo, y el generativismo chomskiano, a partir de la segunda mitad. Más allá de sus importantes diferencias, ambas identificaron como su objeto de estudio a una cierta estructura: la langue y no la parole, y la competence y no la performance, respectivamente (Hurford 2012;Peregrin 2012). Distinguieron, por un lado, la formalización de la estructura fonológica, morfológica y/o sintáctica, y por el otro, el código lingüístico (Perniss 2018), ambos estudiados en una dimensión sincrónica (Anderson 2016) o "procesualmente neutral" (Straight 1993: 208). ...
... Hockett está más cerca de Chomsky en este punto. Sin embargo, el enfoque "biolingüístico" chomskiano no se condice con el aislamiento que la teoría mantuvo respecto de las investigaciones interdisciplinarias sobre los orígenes evolutivos del lenguaje (Hurford 2012), un reproche que no cabe hacerle a Hockett. 3 Como se verá más adelante, según mi opinión, la posición de Hockett es más adecuada que la de Chomsky en diversos puntos. ...
Comparative studies about human language and animal communication systems, so as the research field about language evolution, have stimulated a specific reflection about the distinctive features of human language. My aim is to examine the model of the design features proposed by Charles Hockett, whose influence has been significant on both aforementioned areas. My purpose is to highlight how the presuppositions, under which the preeminence of the structure over the function and of the features of the code over the cognitive abilities of its users are based (both common to other formal approaches that were the dominant ones in linguistics), turn it into a theoretically ineffective tool on both research fields. In particular, I will object to the role that this model has attributed to the first two design features: the vocal-auditory channel and the arbitrariness. Finally, I will contrast it with the language usage-based approaches, supported by the opposite presuppositions. These approaches characterize language as a “mosaic” of cognitive, individual and social, abilities that manifest on a variety of vehicles and modalities; therefore, these provide more suitable theoretical tools than formal approaches to explain language evolution, so as its differences and similarities to animal communication systems.
... К настоящему времени в американской, российской и европейской научных школах сложился относительный консенсус по вопросу диахронической глубины возникновения человеческого языка: считается, что это произошло примерно 200-150 тыс. л. н. [7][8][9][10][11][12][13][14][15][16]. В отношении же периодизации стадий эволюции языка (от состояния простейшей иконической системы, описываемой в виде схемы "me-Tarzan-you-Jane", до стадии полноценного языка: «Гнев, богиня, воспой Ахиллеса, Пелеева сына…») нет не только консенсуса (как по критериям, так и по хронологическим рамкам), но и сложившегося научного направления, ...
... К настоящему времени в американской, российской и европейской научных школах сложился относительный консенсус по вопросу диахронической глубины возникновения человеческого языка: считается, что это произошло примерно 200-150 тыс. л. н. [7][8][9][10][11][12][13][14][15][16]. В отношении же периодизации стадий эволюции языка (от состояния простейшей иконической системы, описываемой в виде схемы "me-Tarzan-you-Jane", до стадии полноценного языка: «Гнев, богиня, воспой Ахиллеса, Пелеева сына…») нет не только консенсуса (как по критериям, так и по хронологическим рамкам), но и сложившегося научного направления, А.Е. ...
The paper considers the long-ago perceived, but inadequately studied phenomenon of the Semitic root triconsonantism. Some examples of the paradigm realization from the Biblical Hebrew, where the adducing of the third consonant to a 2C-root (biconsonantal) results in the formation of a cluster of the semantically related 3C-roots, are provided. A similar process is noted in other language families that constitute the Afroasiatic phylum. Here it is argued that the phenomenon can be viewed diachronically as a consequence of certain economic, social, and cultural changes during the Natufian period (12 500 – 10 500 BP) in the Near East. Due to the material innovations in agriculture, the Natufians were able to store the agricultural surpluses, and their everyday life became more organized and safer. A hypothesis is made that sociocultural changes during the Paleolithic–Neolithic transition influenced the mundane life of the multiplied and urbanized Natufians, who could now rely on food stocks which allowed them to indulge in idle contacts. These changes led, in turn, to an incentive for spiritual progress and ultimately provided a staging ground for oral lore. The new Neolithic reality demanded novel means of expression that were created by the compounding of 3C-roots (among them, the roots bearing an abstract meaning) from the existing 2C-roots.
... The combinatorial diversity seen in the reuse and recombination of a finite set of smaller meaningless acoustic elements into meaningful units, which are then combined into infinite structures of higher-order phrases, is unique to human language [1,2]. Yet, producing long sequences composed of smaller units has also been demonstrated across non-human animals, where producers combine multiple calls into larger meaningful structures. ...
... min). To avoid any bias due to very short recordings, we removed all recordings with less than 10 calls resulting in 162 recordings from 60 adults (median 4 recordings per individual, range 1-10) and 129 recordings from 39 subadult individuals (median 5 recordings per individual, range [1][2][3][4][5][6][7][8]. Although some individuals were only recorded once or a few times, they were still included in the analysis as it has been demonstrated that these data points are still valuable to assess betweenindividual variation [40]. ...
Background:
The ability to recombine smaller units to produce infinite structures of higher-order phrases is unique to human language, yet evidence of animals to combine multiple acoustic units into meaningful combinations increases constantly. Despite increasing evidence for meaningful call combinations across contexts, little attention has been paid to the potential role of temporal variation of call type composition in longer vocal sequences in conveying information about subtle changes in the environment or individual differences. Here, we investigated the composition and information content of sentinel call sequences in meerkats (Suricata suricatta). While being on sentinel guard, a coordinated vigilance behaviour, meerkats produce long sequences composed of six distinct sentinel call types and alarm calls. We analysed recordings of sentinels to test if the order of the call types is graded and whether they contain additional group-, individual-, age- or sex-specific vocal signatures.
Results:
Our results confirmed that the six distinct types of sentinel calls in addition to alarm calls were produced in a highly graded way, likely referring to changes in the perceived predation risk. Transitions between call types one step up or down the a priory assumed gradation were over-represented, while transitions over two or three steps were significantly under-represented. Analysing sequence similarity within and between groups and individuals demonstrated that sequences composed of the most commonly emitted sentinel call types showed high within-individual consistency whereby adults and females had higher consistency scores than subadults and males respectively.
Conclusions:
We present a novel type of combinatoriality where the order of the call types contains temporary contextual information, and also relates to the identity of the caller. By combining different call types in a graded way over long periods, meerkats constantly convey meaningful information about subtle changes in the external environment, while at the same time the temporal pattern of the distinct call types contains stable information about caller identity. Our study demonstrates how complex animal call sequences can be described by simple rules, in this case gradation across acoustically distinct, but functionally related call types, combined with individual-specific call patterns.
... Within and across species, the combinatorial forms characterizing animal vocal systems involve an interesting degree of structural and semantic complexity (Hurford, 2012a;Marler & Slabbekoorn, 1999). Classically, vocal sequences produced by animals have been categorized as either a form of phonological syntax (or combinatoriality) if the sequences are composed of so-called meaningless elements; or alternatively as a form of lexical syntax (or compositionality) if a sequence constitutes a combination of, and derives its overall meaning from, individually meaningful signals (Hurford, 2007;Marler, 1977). ...
... Notably, the resultant structure does not appear to be produced and processed in a compositional way, since the meaning of the whole cannot be derived from its compounds. As such the sequence is suggested to constitute a semantically combinatorial or idiomatic structure (Arnold & Zuberbühler, 2012;Hurford, 2007Hurford, , 2012a. ...
A key challenge in the field of human language evolution is the identification of the selective conditions that gave rise to language's generative nature. Comparative data on nonhuman animals provides a powerful tool to investigate similarities and differences among nonhuman and human communication systems and to reveal convergent evolutionary mechanisms. In this article, we provide an overview of the current evidence for combinatorial structures found in the vocal system of diverse species. We show that considerable structural diversity exits across and within species in the forms of combinatorial structures used. Based on this we suggest that a fine‐grained classification and differentiation of combinatoriality is a useful approach permitting systematic comparisons across animals. Specifically, this will help to identify factors that might promote the emergence of combinatoriality and, crucially, whether differences in combinatorial mechanisms might be driven by variations in social and ecological conditions or cognitive capacities.
This article is categorized under:
• Cognitive Biology > Evolutionary Roots of Cognition
• Linguistics > Evolution of Language
... Linguists have tried other methods to establish grammatical processes and earlier forms of a language or languages. Recent research on language evolution (Hurford & Dediu 2009;Hurford 2011a; 2011b, among others) and evolution of grammar (Heine & Kuteva 2007), along with research on the typology of the world's languages (Haspelmath et al. 2005) lead us to present the following arguments in favour of Great Andamanese retaining one of the archaic structures of human language. ...
The Great Andamanese is a generic term used to refer to ten different tribes who spoke closely related varieties of the same language in the entire set of the Andaman Islands in the Bay of Bengal. Their language is known by the same name, i.e. Great Andamanese. It constitutes the sixth language family of India, the other five being Indo-Aryan, Dravidian, Tibeto-Burman, Austroasiatic, and Tai-Kadai, all of them spoken in mainland India.
... For several decades, compositionality has been considered one of the hallmarks of human language, setting human communication apart from that of other animals (Hurford, 2011). In past years, however, experimental evidence has shown that several species do not only use complex repertoires to communicate with conspecifics but that their communication systems also often show properties that had long been considered to be uniquely human. ...
Compositionality is the ability to combine meaningful elements into new combinations with novel meanings, and it has long been considered one of the main hallmarks of human communication. However, very few studies have addressed the compositional aspects of communication in species other than humans, although a comparative approach is essential to understand the evolutionary origins of human compositionality. We review previous research on compositionality in the gestural communication systems of nonhuman primates, with a special focus on the multicomponent aspects of compositionality. We start by discussing the importance of a comparative approach to study the evolution of human language and then compare the current state of the art on compositionality in the vocal, facial, and gestural communication systems of primates and other species. We further discuss alternative approaches to study compositionality in primates, which may help overcome some of the current methodological limitations in this research area. In particular, we 1) highlight the importance of interdisciplinary tools that facilitate the statistical identification of multicomponent and multimodal combinations of signals, 2) discuss different approaches to infer the meaning of signal combinations, with a special focus on the use of contextual cues and meta-communication, and 3) discuss temporal and intentional aspects of compositionality in primates. Finally, we outline possible lines of research for future studies in this area (e.g., more consistent use of terms across research areas, use of different methodological tools and larger datasets, inclusion of developmental approaches), which might shed light into the evolutionary origins of one of the most crucial properties of human communication.
... Linguists have tried other methods to establish grammatical processes and earlier forms of a language or languages. Recent research on language evolution (Hurford & Dediu 2009;Hurford 2011a; 2011b, among others) and evolution of grammar (Heine & Kuteva 2007), along with research on the typology of the world's languages (Haspelmath et al. 2005) lead us to present the following arguments in favour of Great Andamanese retaining one of the archaic structures of human language. ...
Historical Linguistics and Linguistic Typology have been used to demonstrate that PGA is an independent language family of India. Data from extra-linguistic sources such as anthropology, archaeology and genetics have been used as additional supportive evidence. This chapter will give a summary of the findings and will familiarise the audience with some distinct characteristics of the highly endangered language of the hunter-gatherer society of the Great Andamanese population.
... sounds which are acoustically distinguishable and not produced in isolation) and "meaningful" calls (i.e. functionally specific call units) together can function to increase and enhance the communicative output of a species (Marler 1977;Hurford 2012;Zuberbühler 2015). For example, chestnut-crowned babblers (Pomatostomus ruficeps) reuse and rearrange meaningless, acoustic elements to create functionally distinct and perceptually relevant flight and provisioning calls (Engesser et al. 2015). ...
Language is inherently combinatorial, and parallels of this combinatorial capacity are found in non-human systems, with animals combining sounds and calls into larger meaningful structures. However, further analogue examples are central in unveiling the diversity, distribution and evolutionary drivers of combinatoriality. Here, we provide evidence for internal 'meaning-refining' acoustic variation within a larger stereotyped signal in pied babblers (Turdoides bicolor). Using acoustic analyses, we demonstrate that males produce two long, raucous, 'cry-like' structures, both starting with a wind-up segment grading into repetitions of A/single-note or AB/double-note motifs. Behavioral observations indicated that, consistent with similarities in their larger stereotyped structure, both variants function overall in recruiting group members during locomotion, but the internal A or AB sub-structure specifies the precise form of recruitment, from approaching the caller's announced location, to following it over longer distances. Playing back cries from a stationary loudspeaker further supported that the two variants elicit different responses, with more individuals approaching the loudspeaker in response to single-note compared to double-note cries. Additionally, despite similarities in overall distance travelled, group movement was only directional for single-note, but undefined for double-note cries. We suggest that the overall structure of the two cry variants conveys the same general meaning, with embedded variation refining this meaning. We suggest these results further illustrate the variability of generative mechanisms outside of human language and lends support to the hypothesis that combinatorial structuring may have emerged in species with limited or fixed vocal repertoires in order to enhance communicative output.
... For example, the computations underlying phonological and lexical syntax in the language domain seemed to be shared with other human-specific cognitive domains to various degrees: rhythmic synchronization in music (e.g., Patel & Daniele, 2003;Patel, 2003;Patel, 2008); hierarchical structures in music (e.g., Koelsch, Rohrmeier, Torrecuso & Jentschke, 2013), vision (e.g., Jackendoff, 2007a;Gershman, Tenenbaum & Jäkel, 2015) and action perception (e.g., Wakita, 2014); binary structures in arithmetic (e.g., Bender & Beller, 2013). In considering that different subsystems of the human mind operate on different types of discrete symbolic elements along with different sensory-motor systems, it remains to be seen, which linguistic principles belong to the biological capacity and are hardwired properties of the human-specific neural architecture (e.g., Fadiga, Craighero & D'Ausilio, 2009;Jackendoff, 2009;Stout, 2010;Heinz & Idsardi, 2011;Hurford, 2011;Pesetsky & Katz, 2011;Arbib, 2012;Fitch & Martins, 2014). ...
... In particular, the following central messages should be included into teaching materials and curricula: a • the newly constituted status of language evolution research, with its inherently interdisciplinary nature, methodological pluralism, and a growing reliance on empirical research (see e.g. Hurford, 2012); • the cooperative underpinnings of language (e.g. Tomasello, 2008); • the cognitive and socio-cognitive pre-adaptations (Dor et al., 2014); • the role of cultural evolution (Smith & Kirby, 2008) and modelling approaches for simulating the emergence of linguistic structure (e.g. ...
Despite the vigorous development of language evolution research over the last three decades, very little of this progress has trickled into teaching linguistics: so far this important area of the academy has failed to accommodate the bulk of the empirical and theoretical advances. In this paper we report the results of a survey of fourteen popular introductory-level linguistic textbooks, which – with rare exceptions – show that the teaching of language evolution to students of general linguistics rests on out-dated and largely inadequate conceptual frameworks, and fails to communicate major theoretical breakthroughs and empirical results. Based on the feedback from the community of language origins researchers, we formulate an inventory of key messages that should be incorporated into textbooks and curricula.
... In all four arrangements, the meaningless phonemes maintain their acoustic identity across words, and this, paired with the arbitrary relationship between phoneme structure and word meaning, results in words with shared phonemes having distinct semantic content [4]. Such phoneme structure is a basic ingredient of word generation in human language, and when combined with the rules governing assemblages of meaningful words (a syntactic layer), provides much of language's generative power [5][6][7]. Despite the crucial role that phoneme structure plays in language, little is known about how such a capacity might have evolved [8][9][10][11]. ...
The ability to generate new meaning by rearranging combinations of meaningless sounds is a fundamental component of language. Although animal vocalizations often comprise combinations of meaningless acoustic elements, evidence that rearranging such combinations generates functionally distinct meaning is lacking. Here, we provide evidence for this basic ability in calls of the chestnut-crowned babbler (Pomatostomus ruficeps), a highly cooperative bird of the Australian arid zone. Using acoustic analyses, natural observations, and a series of controlled playback experiments, we demonstrate that this species uses the same acoustic elements (A and B) in different arrangements (AB or BAB) to create two functionally distinct vocalizations. Specifically, the addition or omission of a contextually meaningless acoustic element at a single position generates a phoneme-like contrast that is sufficient to distinguish the meaning between the two calls. Our results indicate that the capacity to rearrange meaningless sounds in order to create new signals occurs outside of humans. We suggest that phonemic contrasts represent a rudimentary form of phoneme structure and a potential early step towards the generative phonemic system of human language.
Language is unbounded in its generativity, enabling the flexible combination of words into novel sentences. Critically, these constructions are intelligible to others due to our ability to derive a sentence’s compositional meaning from the semantic relationships among its components. Some animals also concatenate meaningful calls into compositional-like combinations to communicate more complex information. However, these combinations are structurally highly stereotyped, suggesting a bounded system of holistically perceived signals that impedes the processing of novel variants. Using long-term data and playback experiments on pied babblers, we demonstrate that, despite production stereotypy, they can nevertheless process structurally modified and novel combinations of their calls, demonstrating a capacity for deriving meaning compositionally. Furthermore, differential responses to artificial combinations by fledglings suggest that this compositional sensitivity is acquired ontogenetically. Our findings demonstrate animal combinatorial systems can be flexible at the perceptual level and that such perceptual flexibility may represent a precursor of language-like generativity.
Language’s expressive power is one of its key characterising features. This generative capacity is achieved through language’s double articulatory nature: meaningless sounds (phonemes) are combined to create meaningful words (phonology/combinatoriality), and words are assembled into higher-order meaningful phrases (syntax/compositionality). Comparative work on non-human animals investigating the evolutionary origin of combinatorial abilities has so far focused on singing species or on primates. Although these studies have shed light on the combinatorial capacities outside of humans, evidence for basic phoneme-like or semantically compositional structures in non-human communication systems is rare. By taking a comparative approach, investigating the prevalence and diversity of combinatoriality within the discrete call system of two highly social passerine birds, this dissertation aimed to unveil selective drivers promoting combinatorial capacities, and provides analogue examples to, and potential precursors of, language’s combinatorial layers. Work on chestnut-crowned babblers (Pomatostomus ruficeps) demonstrates the reuse of two meaningless sounds (A & B) in different arrangements to generate the functionally distinct AB
Language’s expressive power is one of its key characterising features. This generative capacity is achieved through language’s double articulatory nature: meaningless sounds (phonemes) are combined to create meaningful words (phonology/combinatoriality), and words are assembled into higher-order meaningful phrases (syntax/compositionality). Comparative work on non-human animals investigating the evolutionary origin of combinatorial abilities has so far focused on singing species or on primates. Although these studies have shed light on the combinatorial capacities outside of humans, evidence for basic phoneme-like or semantically compositional structures in non-human communication systems is rare. By taking a comparative approach, investigating the prevalence and diversity of combinatoriality within the discrete call system of two highly social passerine birds, this dissertation aimed to unveil selective drivers promoting combinatorial capacities, and provides analogue examples to, and potential precursors of, language’s combinatorial layers.
Work on chestnut-crowned babblers (Pomatostomus ruficeps) demonstrates the reuse of two meaningless sounds (A & B) in different arrangements to generate the functionally distinct AB ‘flight’ call (a contact call) and BAB ‘prompt’ call (a food-provisioning call). Specifically, the meaning differentiation between the two calls was found to be the result of a single modification, akin to a rudimentary phonemic-like contrast in human language. Work on free-living, habituated southern pied babblers (Turdoides bicolor) revealed that upon encountering predators the birds combine ‘alert’ with ‘recruitment’ calls into a ‘mobbing sequence’. While alert calls were found to be produced in response to low-urgency threats and recruitment calls during group travel, the mobbing sequence seems to combine information on the threat and the requested action with receivers parsing the sequence in a compositional way. Further investigations into the pied babbler recruitment call component indicated that recruitment calls can additionally be produced in form of two longer ‘recruitment cry’ variants, composed of either repetitions of A’/single-note motifs or A’B’/double-note motifs respectively. Although both cries were found to function in recruiting the group during group travel, the cries’ internal structure seemed to specify the form of recruitment, either requesting approach or prompting following over long distances. Accordingly, recruitment cries appear to be characterised by meaning-differentiating variation at the internal structure level of a larger meaningful signal. Lastly, this dissertation provides evidence for meaningful temporal structuring within pied babbler ‘clucks’ and ‘purrs’. While both calls were shown to be composed of repetitions of the same acoustic element, the number of element repetitions was found to encode qualitatively different information. Specifically, longer purrs function to attract dependent offspring to a food source and truncated clucks seem to communally mediate imminent foraging site switches.
The empirical data provided in this dissertation demonstrates that babblers utilise various combinatorial mechanisms, and furthermore indicates that neither meaningful combinations generated from acoustically differentiable meaningless elements, or rudimentary compositional structures, are unique to human language. By demonstrating evidence for meaningful vocal combinations in species distantly related to humans, this work provides fundamental insights into the factors that might have promoted the evolutionary progression of language’s generative system.
This chapter illustrates the various ways in which languages differ from each other and then raises the question in what sense one can talk about universals despite this apparent diversity and variation. It reviews the extent of the diversity that we know from today’s languages in the world, by highlighting the core domains of language: phonology, morphology, syntax, and semantics. In the chapter, the author uses the term language in the sense of a structure identifier, and applies it to any kind of variant set of structures, including dialects, sociolects, and idiolects. The range and nature of absolute universals depends entirely on the nature of the analysis and the descriptive metalanguage that one uses for a particular phenomenon. The criterion of historical realism is foundational for research on statistical as opposed to absolute universals because statistical universals are fundamentally historical in nature.
The discussion about the phylogenetic relation between human and other animals – and between their abilities, both cognitive and communicative ones – traces back to ancient times. In this discussion, language has been one of the main topics for a long time. During the XX century – probably because of the great influence of structuralism and generativism – Linguistics paid little attention to the comparison between human language and animal language, though in recent years a new trend is to be sought. Two linguists – Noam
Chomsky and James Hurford – seem to exemplify the evolution of the discussion: both human and non-human abilities turn out to be the focus of an interdisciplinary and comparative approach that might lead up to a deeper comprehension of the language faculty.
Keywords: human language, animal language, Noam Chomsky, James Hurford, linguistics.
Many primate species reliably track and follow the visual gaze of conspecifics and humans, even to locations above and behind the subject. However, it is not clear whether primates follow a human's gaze to find hidden food under one of two containers in an object-choice task. In a series of experiments six adult female chimpanzees followed a human's gaze (head and eye direction) to a distal location in space above and behind them, and checked back to the human's face when they did not find anything interesting or unusual. This study also assessed whether these same subjects would also use the human's gaze in an object-choice task with three types of occluders: barriers, tubes, and bowls. Barriers and tubes permitted the experimenter to see their contents (i.e., food) whereas bowls did not. Chimpanzees used the human's gaze direction to choose the tube or barrier containing food but they did not use the human's gaze to decide between bowls. Our findings allowed us to discard both simple orientation and understanding seeing-knowing in others as the explanations for gaze following in chimpanzees. However, they did not allow us to conclusively choose between orientation combined with foraging tendencies and understanding seeing in others. One interesting possibility raised by these results is that studies in which the human cannot see the reward at the time of subject choice may potentially be underestimating chimpanzees' social knowledge.
Vocalize-to-Localize? Meerkats do it for specific predators… And babies point with their index finger toward targets of interest at about nine months, well before using language-specific that -demonstratives. With what -interrogatives they are universal and, as relativizers and complementizers, play an important role in grammar construction. Some alarm calls in nonhumans display more than mere localization: semantics and even syntax. Instead of telling another monomodal story about language origin, in this volume advocates of representational gestures, semantically transparent, but with a problematic route toward speech, meet advocates of speech, with a problematic route toward the lexicon. The present meeting resulted in contributions by 23 specialists in the behaviour and brain of humans, including comparative studies in child development and nonhuman primates, aphasiology and robotics. The near future will tell us if the present crosstalk — between researchers in auditory and in visual communication systems — will lead to a more integrative framework for understanding the emergence of babbling and pointing, two types of neural control whose coordination could pave the way toward the word and syntax.
The contributions to this volume were previously published as Interaction Studies 5:3 (2004) and 6:2 (2005).
A fundamental, universal property of human language is that its phonology is combinato-rial. That is, one can identify a set of basic, distinct units (phonemes, syllables) that can be productively combined in many different ways. In this paper, we review a number of theories and models that have been developed to explain the evolutionary transition from holistic to combinatorial signal systems, but find that in all problematic linguistic assumptions are made, or crucial components of evolutionary explanations are omitted. We present a novel model to investigate the hypothesis that combinatorial phonology results from optimising signal systems for perceptual distinctiveness. Our model differs from previous models in two important respects. First, signals are modelled as trajectories through acoustic space. Hence, both holistic and combinatorial signals have a temporal structure. Second, we use the methodology from evolutionary game theory. Crucially, we show a path of ever in-creasing fitness from holistic to combinatorial signals, where every innovation represents an advantage even if no-one else in a population has yet obtained it.
. Many songbirds develop remarkably large vocal repertoires, and this has prompted questions about how birds are able to successfully
learn and use the often enormous amounts of information encoded in their various signal patterns. We have studied these questions
in nightingales (Luscinia megarhynchos), a species that performs more than 200 different types of songs (strophen), or more than 1000 phonetically different elements
composing the songs. In particular, we investigated whether and how both song repertoires and song performance rules of nightingales
were coded by auditory stimuli presented in serial learning experiments. Evaluation of singing episodes produced by our trained
birds revealed that nightingales cope well with an exposure to even long strings of master song-types. They can readily acquire
information encoded within and between the different master songs, and they memorize, for example, which master song-types
they have experienced in the same learning context. Imitations of such song-types form distinct sequential associations that
are termed “context groups”. Additionally, nightingales develop other song-type associations that are smaller in size and
termed “package groups”. Package formation results from constraints of the acquisition mechanisms which obviously lead to
a segmentation of auditorily perceived master song sequences. Further experimentation validated that the song memory of nightingales
is organized in a hierarchical manner and holding information about “context groups” composed of packages, “package groups”
composed of songs, and songs composed of song elements. The evidence suggests that implementation of such a hierarchical organization
facilitates a quick retrieval of particular songs, and thereby provides an essential prerequisite for a functionally appropriate
use of large vocal repertoire is in songbirds.
Ten Japanese macaques were trained to discriminate between two types of Japanese macaque coo vocalizations before and after auditory cortex ablation. Five of the animals were tested following left unilateral ablation, whereas the other five were tested following right unilateral ablation. After postoperative testing, symmetrical lesions were made in the remaining hemisphere in two animals from each group and the effect of bilateral lesions was assessed. The animals were tested using a shock avoidance procedure. Unilateral ablation of left auditory cortex consistently resulted in an initial impairment in the ability to discriminate between the vocalizations with the animals regaining normal performance in 5-15 sessions. In contrast, right unilateral ablation had no detectable effect on the discrimination. Bilateral auditory cortex ablation rendered the animals permanently unable to discriminate between the coos. Although the monkeys could learn to discriminate the coos from noise and from 2- and 4-kHz tones, they had great difficulty in discriminating between the coos and tones in the same frequency range as the coos (i.e., 500 Hz and 1 kHz). The initial impairment following left unilateral lesions indicates that the ability to perceive species-specific vocalizations is lateralized to the left hemisphere. The observation that bilateral lesions abolish the discrimination indicates that the recovery in the left lesion cases was the result of the right hemisphere mediating the discrimination.
Prior research on the ability to solve the Piagetian invisible displacement task has focused on prerequisite representational capacity. This study examines the additional prerequisite of deduction. As in other tasks (e.g., conservation and transitivity), it is difficult to distinguish between behavior that reflects logical inference from behavior that reflects associative generalization. Using the role of negation in logic whereby negative feedback about one belief increases the certainty of another (e.g., a disjunctive syllogism), task-naive dogs (Canis familiaris; n=19) and 4- to 6-year-old children (Homo sapiens; n=24) were given a task wherein a desirable object was shown to have disappeared from a container after it had passed behind 3 separate screens. As predicted, children (as per logic of negated disjunction) tended to increase their speed of checking the 3rd screen after failing to find the object behind the first 2 screens, whereas dogs (as per associative extinction) tended to significantly decrease their speed of checking the 3rd screen after failing to find the object behind the first 2 screens.
Event memory and misinformation effects were examined in an adult male gorilla ( Gorilla gorilla gorilla). The gorilla witnessed a series of unique events, involving a familiar person engaging in a novel behavior (experiment 1), a novel person engaging in a novel behavior (experiment 2), or the presentation of a novel object (experiment 3). Following a 5- to 10-min retention interval, a tester gave the gorilla three photographs mounted on wooden cards: a photograph depicting the correct person or object and two distractor photographs drawn from the same class. The gorilla responded by returning a photograph. If correct, he was reinforced with food. Across three experiments, the gorilla performed significantly above chance at recognizing the target photograph. In experiment 4, the gorilla showed at-chance performance when the event was followed by misinformation (a class-consistent, but incorrect photograph), but significantly above-chance performance when no misinformation occurred (either correct photograph or no photograph). Although the familiarity can account for these data, they are also consistent with an episodic-memory interpretation.
We provide a tripartite overview of HPSG, a constraint-based model-theoretic framework for grammatical representation widely used for both theoretical research and computational implementations of natural language grammars. We begin with a condensed survey of the descriptive machinery assumed in the theory, focusing on the feature-based encoding of grammatical properties and the form of constraints regulating the specification of values for these features in complex syntatic structures, with illustrations from various local and nonlocal dependencies exhibited in a range of grammatical constructions. The following section explores in some detail the logical and formal foundations of the descriptive apparatus, centered on the crucial ontological distinction between, on the one hand, formal objects embodying the properties of linguistic expressions, and on the other, descriptions of those objects. We conclude with a review of HPSG-based processing, including the motivations behind such work, the different computational approaches and systems, as well as current strands of research.
This chapter provides philosophical perspective on self-consciousness contributing a historical grounding for modern theories. The chapter assesses the extent to which animals might be self-conscious by applying two epistemological criteria to their behavior: episodic memory and metacognition. In the case of moral responsibility, the chapter asks whether an animal could think back to a past action that was punished and try to make amends if given the opportunity. In the case of epistemic self-improvement, the chapter asks whether animals can notice when they lack sufficient information to solve a problem and proceed to obtain that information. Modern philosophers regarded self-consciousness as marking the fundamental divide between humans and other animals. The central normative tasks assigned to self-consciousness by the moderns have either analogues with animal capacities or components in common with animal capacities. Modern philosophers believed that in self-consciousness they had finally found the key to human uniqueness.
Humans have the capacity to feel consciously uncertain and to know when they do not know. These feelings and responses ground the research literature on uncertainty monitoring and metacognition (i.e., cognition about cognition). It is a natural and important question whether nonhuman animals share this sophisticated cognitive capacity. We summarize current research that confirms animals' capacity for uncertainty monitoring. This research includes perception and memory paradigms and monkey, dolphin, and human participants. It contains some of the strongest existing performance similarities between humans and other animals. There is a strong isomorphism between the uncertainty-monitoring capacities of humans and animals. Indeed, the results show that animals have functional features of or parallels to human metacognition and human conscious cognition.
It is necessary to distinguish among representations caused directly by perception, representations of past perceptions in long-term memory, the representations underlying linguis- tic utterances, and the surface phonological and grammatical structures of sentences. The target article dealt essentially with predicate-argument structure at the first of these levels of representation. Discussion of the commentaries mainly involves distinguishing among various applications of the term “predicate”; clarifying the assumed relationship between classical FOPL and language; clarifying the status of unique individuals as conceived by humans; and addressing the issues of motion-perception, binding between object-percepts and predicate-percepts, and target-driven versus stimulus-driven attention.
There was a strong consensus in the commentaries that animals' performances in metacognition paradigms indicate high-level decisional processes that cannot be explained associatively. Our response summarizes this consensus and the support for the idea that these performances demonstrate animal metacognition. We amplify the idea that there is an adaptive advantage favoring animals who can – in an immediate moment of difficulty or uncertainty – construct a decisional assemblage that lets them find an appropriate behavioral solution. A working consciousness would serve this function well. This explains why animals may have the functional equivalent of human declarative consciousness. However, like other commentators who were friendly to this equivalence, we approach carefully the stronger claims that animals' metacognitive performances imply full-blown self-awareness or phenomenal consciousness.
We discuss the commentators' interesting ideas for future research, as well as their intriguing ideas about the evolution and development of metacognition and its relation to theory of mind. We also discuss residual confusions about existing research and remaining methodological issues.
The perception of consonants which were followed by the vowel [a] was studied in chimpanzees and humans, using a reaction
time task in which reaction times for discrimination of syllables were taken as an index of similarity between consonants.
Consonants used were 20 natural French consonants and six natural and synthetic Japanese stop consonants. Cluster and MDSCAL
analyses of reaction times for discrimination of the French consonants suggested that the manner of articulation is the major
determinant of the structure of the perception of consonants by the chimpanzees. Discrimination of stop consonants suggested
that the major grouping in the chimpanzees was by voicing. The place of articulation from the lips to the velum was reproduced
only in the perception of the synthetic unvoiced stop consonants in the two dimensional MDSCAL space. The phoneme-boundary
effect (categorical perception) for the voicing and place-of-articulation features was also examined by a chimpanzee using
synthetic [ga]-[ka] and [ba]-[da] continua, respectively. The chimpanzee showed enhanced discriminability at or near the phonetic
boundaries between the velar voiced and unvoiced and also between the voiced bilabial and alveolar stops. These results suggest
that the basic mechanism for the identification of consonants in chimpanzees is similar to that in humans, although chimpanzees
are less accurate than humans in discrimination of consonants.
The perception of vowels was studied in chimpanzees and humans, using a reaction time task in which reaction times for discrimination
of vowels were taken as an index of similarity between vowels. Vowels used were five synthetic and natural Japanese vowels
and eight natural French vowels. The chimpanzees required long reaction times for discrimination of synthetic [i] from [u]
and [e] from [o], that is, they need long latencies for discrimination between vowels based on differences in frequency of
the second formant. A similar tendency was observed for discrimination of natural [i] from [u]. The human subject required
long reaction times for discrimination between vowels along the first formant axis. These differences can be explained by
differences in auditory sensitivity between the two species and the motor theory of speech perception. A vowel, which is pronounced
by different speakers, has different acoustic properties. However, humans can perceive these speech sounds as the same vowel.
The phenomenon of perceptual constancy in speech perception was studied in chimpanzees using natural vowels and a synthetic
[o]- [a] continuum. The chimpanzees ignored the difference in the sex of the speakers and showed a capacity for vocal tract
normalization.
The current paper examines if gorillas (Gorilla gorilla gorilla) possess an episodic memory system. Episodic memory, in humans, is a neurocognitive system that stores information about the personal past. Unique to episodic memory is its palinscopic or past-focused orientation; most memory systems serve to provide the organism with up to date knowledge of the current state of the world. We review four operational definitions that have been used to address issues of episodic memory in non-humans and review the literature with a focus on the studies previously done on gorillas. We describe two new studies with King, an adult male western lowland gorilla. We show that King can remember the order of past events (Experiment 1) and that King can remember where events occurred (Experiment 2). We conclude by discussing alternate explanations of our findings and speculate on future directions.
Monkeys of four species were trained to discriminate between sets of natural tonal calls of Japanese macaques (Macaca fuscata)
by the position of a frequency-inflection peak or by initial pitch. The Japanese macaques consistently performed best on peak
position and the other species on pitch. The results imply special strategies for perceptional processing of vocal sounds
and suggest parallels with human speech perception.
This article approaches the linguistic innateness issue from the perspective of a nonhuman species, the bonobo, an ape which is generally taken to be the best living model for early hominids. Recent studies indicate that a bonobo reared with humans comes spontaneously to comprehend spoken words, to produce novel two word combinations, and to respond appropriately to syntactically ordered sentences.
The differences between the use of word combinations to say what one word can accomplish and combinations that convey a novel idea not transmittable by a single word is emphasized. It is argued that the use of such novel combinations must have preceded the appearance of syntax in the evolution of language. The use of multiword novel combinations has not received sufficient attention in the literature because of the erroneous assumption that novel meanings could only be achieved through syntactical structure. Consequently the significance of the ape's linguistic competence has been severely undervalued.
The processes that underlie perception of consonants and vowels are specifically phonetic, distinct from those that localize sources and assign auditory qualities to the sound from each source. This specialization, or module, increases the rate of information flow, establishes the parity between sender and receiver that every communication system must have, and provides for the natural development of phonetic structures in the species and in the individual. The phonetic module has certain properties in common with modules that are "closed" (for example, sound localization or echo ranging in bats) and, like other members of this class, is so placed in the architecture of the auditory system as to preempt information that is relevant to its special function. Accordingly, this information is not available to such "open" modules as those for pitch, loudness, and timbre.
In humans, the left hemisphere of the brain is dominant for processing language. To assess the evolutionary origins of this neuropsychological mechanism, playback experiments were conducted on a large population of free-ranging rhesus monkeys (Macaca mulatta). Playbacks provided an equal opportunity to orient the right or left ear toward the speaker. Results revealed that 61 of 80 adult rhesus favored the right ear (left hemisphere) when vocalizations from their own repertoire were heard but favored the left ear when listening to heterospecific vocalizations. In contrast, infants less than a year old showed no perceptual asymmetry for conspecific or heterospecific calls. Thus, like humans, adult rhesus monkeys also evidence left hemisphere dominance for processing species-specific vocalizations. The emergence of such asymmetry, however, may depend on both differential maturation of the two hemispheres and experience with the species-typical vocal repertoire.
Previous investigations of the linguistic capacities of apes have focused on the ape's ability to produce words, and there has been little concern for comprehension. By contrast, it is increasingly recognized that comprehension precedes production in the language development of normal human children, and it may indeed guide production. It has been demonstrated that some species can process speech sounds categorically in a manner similar to that observed in humans. Consequently, it should be possible for such species to comprehend language if they have the cognitive capacity to understand word-referent relations and syntactic structure. Popular theories of human language acquisition suggest that the ability to process syntactic information is unique to humans and reflects a novel biological adaptation not seen in other animals. The current report addresses this issue through systematic experimental comparisons of the language comprehension skills of a 2-year-old child and an 8 year-old bonobo (Pan paniscus) who was raised in a language environment similar to that in which children are raised but specifically modified to be appropriate for an ape. Both subjects (child and bonobo) were exposed to spoken English and lexigrams from infancy, and neither was trained to comprehend speech. A common caretaker participated in the rearing of both subjects. All language acquisition was through observational learning. Without prior training, subjects were asked to respond to the same 660 novel sentences. All responses were videotaped and scored for accuracy of comprehension of the English language. The results indicated that both subjects comprehended novel requests and simple syntactic devices. The bonobo decoded the syntactic device of word recursion with higher accuracy than the child; however, the child tended to do better than the bonobo on the conjunctive, a structure that places a greater burden on short-term memory. Both subjects performed as well on sentences that required the ability to reverse work order as they did on sentences that did not require this capacity. These results are discussed in light of a model of the evolution of language that suggests that the potential for language comprehension preceded the appearance of speech by several million years at minimum. The onset of speech is linked to the appearance of fully adapted bipedalism, which necessitated reorientation of the laryngeal tract and made closure of the soft palate possible. For the first time, such closure permitted mammals to easily produce sounds that could be interpreted by the mammalian auditory system in a categorical manner. When these sounds were paired with the previously extant capacity to produce vowels, it became possible to form "bounded vowels" or sound units that could readily be discriminated as units by the auditory system. It is suggested that this physical adaptation allowed the extant cognitive capacity of the hominids to embark on a speech-like mode of communication.
The mammalian hypoglossal canal transmits the nerve that supplies the muscles of the tongue. This canal is absolutely and relatively larger in modern humans than it is in the African apes (Pan and Gorilla). We hypothesize that the human tongue is supplied more richly with motor nerves than are those of living apes and propose that canal size in fossil hominids may provide an indication about the motor coordination of the tongue and reflect the evolution of speech and language. Canals of gracile Australopithecus, and possibly Homo habilis, fall within the range of extant Pan and are significantly smaller than those of modern Homo. The canals of Neanderthals and an early “modern” Homo sapiens (Skhul 5), as well as of African and European middle Pleistocene Homo (Kabwe and Swanscombe), fall within the range of extant Homo and are significantly larger than those of Pan troglodytes. These anatomical findings suggest that the vocal capabilities of Neanderthals were the same as those of humans today. Furthermore, the vocal abilities of Australopithecus were not advanced significantly over those of chimpanzees whereas those of Homo may have been essentially modern by at least 400,000 years ago. Thus, human vocal abilities may have appeared much earlier in time than the first archaeological evidence for symbolic behavior.
• language evolution
• human evolution
• Homo
• Pan
• Australopithecus
Many cognitive and physical features must have undergone change for the evolution of fully modern human language. One neglected aspect is the evolution of increased breathing control. Evidence presented herein shows that modern humans and Neanderthals have an expanded thoracic vertebral canal compared with australopithecines and Homo ergaster, who had canals of the same relative size as extant nonhuman primates. Based on previously published analyses, these results demonstrate that there was an increase in thoracic innervation during human evolution. Possible explanations for this increase include postural control for bipedalism, increased difficulty of parturition, respiration for endurance running, an aquatic phase, and choking avoidance. These can all be ruled out, either because of their evolutionary timing, or because they are insufficiently demanding neurologically. The remaining possible functional cause is increased control of breathing for speech. The main muscles involved in the fine control of human speech breathing are the intercostals and a set of abdominal muscles which are all thoracically innervated. Modifications to quiet breathing are essential for modern human speech, enabling the production of long phrases on single expirations punctuated with quick inspirations at meaningful linguistic breaks. Other linguistically important features affected by variation in subglottal air pressure include emphasis of particular sound units, and control of pitch and intonation. Subtle, complex muscle movements, integrated with cognitive factors, are involved. The vocalizations of nonhuman primates involve markedly less respiratory control. Without sophisticated breath control, early hominids would only have been capable of short, unmodulated utterances, like those of extant nonhuman primates. Fine respiratory control, a necessary component for fully modern language, evolved sometime between 1.6 Mya and 100,000 ya.
An understanding of the acoustic cues that animals use to categorize their vocalizations has important implications for the way we design neuroethological investigations of auditory function. Compared to other species, we know relatively little about the kinds of acoustic features used by nonhuman primates to recognize and categorize vocalizations. To further our understanding, this study explores the role of temporal features in recognition of conspecific vocalizations by rhesus macaques (Macaca mulatta). Experiments were designed to extend an earlier set of findings showing that adult rhesus macaques selectively turn with the right ear leading when a conspecific vocalization is played 180 degrees behind them, but turn left or not at all when a non-conspecific signal is played. Two call types were used as stimuli: shrill barks (alarm call) and harmonic arches (food call). We found that for normal calls, rhesus macaques turned to the right - supporting earlier findings - but for time- reversed shrill barks and harmonic arches, subjects oriented to the left. These results suggest that for at least a subset of calls, rhesus macaques use temporal cues to recognize conspecific vocal signals. The asymmetry of the behavioral response, and the corresponding asymmetry in the time-amplitude waveform, may have important implications for studies of temporal coding in the primate auditory system.
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Neural correlates exist for a basic component of logical formulae, PREDICATE(x). Vision and audition research in primates and humans shows two independent neural pathways; one locates objects in body-centered space, the other attributes properties, such as colour, to objects. In vision these are the dorsal and ventral pathways. In audition, similarly separable "where" and "what" pathways exist. PREDICATE(x) is a schematic representation of the brain's integration of the two processes of delivery by the senses of the location of an arbitrary referent object, mapped in parietal cortex, and analysis of the properties of the referent by perceptual subsystems. The brain computes actions using a few "deictic" variables pointing to objects. Parallels exist between such nonlinguistic variables and linguistic deictic devices. Indexicality and reference have linguistic and nonlinguistic (e.g., visual) versions, sharing the concept of attention. The individual variables of logical formulae are interpreted as corresponding to these mental variables. In computing action, the deictic variables are linked with "semantic" information about the objects, corresponding to logical predicates. Mental scene descriptions are necessary for practical tasks of primates, and preexist language phylogenetically. The type of scene descriptions used by nonhuman primates would be reused for more complex cognitive, ultimately linguistic, purposes. The provision by the brain's sensory/perceptual systems of about four variables for temporary assignment to objects, and the separate processes of perceptual categorization of the objects so identified, constitute a pre-adaptive platform on which an early system for the linguistic description of scenes developed.
Understanding the intentional actions of others is a fundamental part of human social cognition and behavior. An important question is therefore whether other animal species, especially our nearest relatives the chimpanzees, also understand the intentional actions of others. Here we show that chimpanzees spontaneously (without training) behave differently depending on whether a human is unwilling or unable to give them food Chimpanzees produced more behaviors and left the testing station earlier with an unwilling compared to an unable (but willing) experimenter These data together with other recent studies on chimpanzees' knowledge about others' visual perception show that chimpanzees know more about the intentional actions and perceptions of others than previously demonstrated
Human newborns discriminate languages from different rhythmic classes, fail to discriminate languages from the same rhythmic class, and fail to discriminate languages when the utterances are played backwards. Recent evidence showing that cotton-top tamarins discriminate Dutch from Japanese, but not when utterances are played backwards, is compatible with the hypothesis that rhythm discrimination is based on a general perceptual mechanism inherited from a primate ancestor. The present study further explores the rhythm hypothesis for language discrimination by testing languages from the same and different rhythmic class. We find that tamarins discriminate Polish from Japanese (different rhythmic classes), fail to discriminate English and Dutch (same rhythmic class), and fail to discriminate backwards utterances from different and same rhythmic classes. These results provide further evidence that language discrimination in tamarins is facilitated by rhythmic differences between languages, and suggest that, in humans, this mechanism is unlikely to have evolved specifically for language.