Search Results

This chapter has three main objectives. First, it briefly summarizes the reasons why language might have evolved, and what we are to make of these. It then considers what this has to tell us about why only the hominin lineage evolved the capacity for language. Finally, it revisits the author's previous analyses (Aiello and Dunbar 1993) on the timing of language evolution in the hominin fossil record using new estimates for all the equations involved, in order to explore the sequence by which language might have evolved, and the transitional states involved.

This chapter argues that it is ‘too simplistic’ to view language as primarily a symbolic system used for communication. This view leads to an interpretation of the archeological record that is ‘too naïve’. Central to this argument is the assumption that natural language is a computational system by which linguistic form and semantic interpretation are mapped systematically onto each other. The mapping is based on an inventory of lexical items and a combinatory system that includes the process known as ‘recursion’ which, roughly, has the capacity to form infinitely long sentences by embedding phrases within phrases. The introduction of this process altered the nature of linguistic signs, severing the direct connection between form and interpretation. This gave rise to desymbolization, which is the ‘most characteristic’ property of language. If this view is correct, evidence of symbolic activity by itself would not be a proper diagnostic of the presence of language.

This chapter explores the idea that language and music may have co-evolved, and proposes that language and music constitute complementary components of the ‘human communicative toolkit’. Drawing on ethnomusical, cognitive, and neuroscientific evidence, it is argued that music is a communicative medium with features that are optimally adapted for the management of situations of social uncertainty. Music achieves this by presenting the characteristics of an honest signal, while underspecifying goals in a way that permits individuals to interact even while holding personal interpretations of goals and meanings that may actually be in conflict. The chapter adduces a theory of meaning in music, in which the experience of music is accounted for in specific ways by reference to principles that are said to underlie both animal communication in general, and human communicative interaction in particular. Exploring the implications of this theory for the evolution of language, it is argued that as complementary components of the ‘modern human communicative toolkit’, music and language are best thought of as having co-evolved from a precursive communicative system that embodied features of both.

Recursion is considered to be the hallmark of modern language. This chapter addresses fundamental questions about its evolutionary emergence: ‘What is the relationship of recursion to modern language and thinking?’ and ‘What might be the mechanism or subspecies of recursion that bestows its advantages to cognition?’ In addressing these questions, empirical evidence is presented which shows that recursion requires not only greater working memory capacity but also greater phonological storage capacity. The chapter proposes that recursion arose as a function of an increase in phonological storage capacity and/or working memory capacity. These capacities were enhanced by a genetic neural mutation that occurred sometime between 150,000 and 30,000 years ago. That change made possible longer recursive and canonical utterances and a consequent increase in the complexity and information content of sentences.

This chapter sets out a strategy for investigating the evolutionary biology of language. Central here is the following thesis: In order to understand the emergence of linguistic capacity as an innovation in the hominid line, it is necessary to work backwards from language-relevant anatomy. The assumption is that each piece of the anatomical mosaic will have a different evolutionary story, and that each story will be more or less evident in ancestral species, depending on the availability of biological evidence in the fossil record. The use of this strategy is illustrated by discussing the evolution of Broca's area and the parietal-occipital-temporal junction (POT) plus Wernicke's area — areas of the brain that are ‘necessary, if not sufficient, for language’. It is argued that the complex comprising Broca's area and the POT was evolutionarily shaped to improve the neurological control of the hand and thumb, and became available for exaptation after the divergence of the hominid and pongid lineages. This position gains further support from recent work on primate neuroanatomy.

The human mental lexicon is the repository of many tens of thousands of distinct vocabulary items, and of stored information about their word classes and their selectional and subcategorization requirements. Even in its simplest form — before the syntactic capacity emerges — the lexicon requires a number of distinctive characteristics to have evolved, such as the ability to link an abstract symbol to the concept it represents, the ability to retrieve lexical items from storage quickly, and for that retrieval to be under voluntary control. This chapter investigates the origins of some of the basic features of the lexicon, focusing on the prerequisites for the production and comprehension of a simple protolanguage. It proposes that a word-based lexicon evolved by building on ancient conceptual categories which are likely shared by many primates. This lexicon also utilized a pre-existing semantic organization, and built on the hierarchical structure already in place in primate cognition.

This chapter argues that we should return to ideas about the relationship between language and music advocated by scholars such as Rousseau, Darwin, and Jespersen. It further articulates the view that language and music co-evolved — a view that is tied in with recent arguments to the effect that protolanguage was holistic. It is argued that the proposal of a music-like protolanguage enables us not only to explain certain continuities between human speech and primate vocal communication but also to explain the seeming alacrity with which newborn infants respond to language and music alike, and the significant overlaps of the respective brain regions recruited for language and music. In addition, the chapter cites different reasons for assuming that protolanguage used holistic phrases, not compositional ones. It discusses a number of reasons why so-called hominin holistic phrase communication would have had a degree of musicality. In interweaving various strands of evidence, the chapter illustrates the extent to which work on language evolution has become an interdisciplinary endeavor.

This chapter reviews evidence for deixis in great apes. Some of this evidence suggests that great apes easily develop deictic repertoires in the complete absence of any explicit attempt to train them. It is argued that deixis — in the sense of the ability to direct the attention of another to a specific locus — is a capacity shared by great apes and humans. Assuming that deixis in great apes cannot ultimately derive from bipedalism or other adaptations, our hominin ancestors were pre-adapted for joint attention, which makes deixis a component of the faculty of language in the broad sense of Hauser, Chomsky, and Fitch (2002).

This chapter reports theoretical research exploring the hypothesis that language evolved in a cultural fashion as a complex adaptive system. It does not propose a theory to explain how sociality may have arisen or how it gets reinforced by an existing language system. Instead, it examines the extent to which ultrasociality is indeed a crucial prerequisite. Is it the case that if the sociality assumption is not adopted at the linguistic level, communication systems do not get off the ground at all? Is sociality not only a sufficient but also a necessary condition for the emergence and transmission of complex symbol-based communication? And how strict does sociality have to be? Is it possible that some form of linguistic cheating can be tolerated? And how can an existing communication system reinforce sociality once it has emerged? Before delving into these issues, the chapter first summarizes the main hypothesis for the cultural evolution of language (section 3.2), gives an example of the language-game experiments we have been carrying out (section 3.3), and then turns to the sociality question itself (section 3.4).

Standard evolutionary theory is highly successful, based as it is on solid mathematical foundations and a rich empirical tradition, constantly renewed by exchanges of hypotheses and data among diverse researchers. Yet, despite its successes, it does not provide a satisfactory basis for understanding human evolution. Primarily, this is because standard evolutionary theory's assumptions limit what it can explain. Significantly, it largely neglects the role of niche-construction in evolution. As a result, it has inadvertently erected conceptual barriers that make it difficult to integrate evolutionary biology with several neighboring disciplines, including developmental biology, ecosystem-level ecology, and the human sciences. This chapter describes how niche construction can usefully be regarded as a process which, combined with established evolutionary processes, improves understanding of human evolution. By integrating human niche construction with gene-culture co-evolutionary theory, an evolutionary framework to explore the evolution of language is developed.

Estimates about the origin of modern human language range from 50,000 to 150,000 years ago. These estimates are based on archeological findings, the presence of tools and beads in e.g. the Blombos cave at 70,000 years ago, and mutations in a gene connected to speech (FOXP2) at about 120,000 years ago. Genetics and archeology work well together and suggest a homeland for modern humans in Africa. What can linguistics contribute to this picture? This chapter shows that a biolinguistic approach has much to offer. The chapter is organized as follows. Section 12.2 presents a very general picture of the Minimalist Program, and in particular its biolinguistic focus. This framework is elaborated on in Section 12.3, especially where the operation Merge is concerned. Sections 12.4 and 12.5 focus on grammaticalization, discussing how it follows from economy and how it is relevant to language evolution; Section 12.6 concludes.

Damage to the frontal lobes, particularly on the left, will impair language capacity. This chapter reviews language impairment at four discrete, although overlapping, levels of clinical phenomena: (1) transcortical motor aphasia (TCMA), the classical aphasic syndrome of left posterior frontal injury; (2) dynamic aphasia, which is the core impairment of (TCMA) and a disturbance of complex, open—ended sentence assembly; (3) discourse impairments, which are disturbances in the assembly of complex narratives; and (4) disrupted action planning, the fundamental impairment of complex, goal-directed, intentional behavior. Dynamic aphasia and discourse impairment should be seen as action planning deficits specific to language use.

This chapter explores the potential of social play to generate shared fields of reference and simple rules in the co-construction of intentional actions and routines in which players demonstrate mutual awareness through structured signals, monitoring the attention of others, and cooperative engagement with an object. Co-constructed actions negotiate the means to mutually acceptable ends, and rules emerge that redirect the flow into familiar kinds of games. Repetition, with variation, creates rules that govern and bind a flexible repertory of basic motor skills, social responses, and communicative behavior. The response of a player redefines and/or limits another's intent; thus the shared semantic understandings of objects, actions, and/or gestures that signal, query, or motivate the next move emerge as a function of this interaction. Co-constructed intentions are inherently shared, and salient gestures, sounds, and ‘incipient acts’ evoke the meaning of moves that have been played into existence. Because play actions, movements, and gestures are often without their ‘real world’ consequences or instrumental functions, these salient acts can become free to ‘stand for’ or re-present their meaning in non-play contexts. In social play as in language, participants negotiate hierarchically ordered moves and exchanges that can be modified and rearranged through repetitive actions and shared goals into normative, rule-governed behavior. These dialogic structural and normative functions make social play a proper model for understanding the emergence of language as a negotiated, self-organizing system rather than a system of communication limited to modern human societies.

This chapter presents observations that suggest wild chimpanzees use a gesture, the directed scratch, in a referential fashion. Directed scratches share two crucial components with homesign systems. They involve some form of reference and may specify a distinct action, therefore qualifying as characterizing signs. Although homesign systems go a step beyond, by exhibiting simple grammatical structure and recursion, directed scratches may constitute the first step toward symbolic gestures. These findings are consistent with the hypothesis that gestures used by our closest living relatives might have been the crucial modality within which the evolutionary precursors of symbolic communication evolved. Additional comparative research investigating the factors triggering the development of referential gestures will be required to resolve what is unique to humans and what constitutes ‘fossil’ forms of human language or language abilities.

This chapter investigates the effect of the lowering of the larynx in humans, providing an articulatory/acoustic perspective on the evolution of speech. It uses Mermelstein's model of the geometry of the human male vocal tract, a model in which the contours correspond to the actions of the muscles involved in speech. In the experiment, the area of the acoustic space that is accessible by a model of the male vocal tract — a space similar to the maximum vowel space — is compared with the accessible area of the female vocal tract. Simulation results show the female vocal tract is better than the male tract for producing distinctive speech sounds. This indicates that there is an evolutionary advantage to a vocal tract that has a pharyngeal and an oral cavity of equal length, as in the case of the female tract. It is argued that a different evolutionary explanation for the lower position of the male larynx needs to be found, the theory of size exaggeration as proposed by Tecumseh Fitch and his colleagues being a likely candidate.

This chapter argues that variation is a constitutive property of language use; its study allows one to explain how grammars change over time. The present discussion is concerned with the latter issue, i.e. the restructuring of grammars underlying language use. Starting from the assumption that language acquisition is a likely source of change, it is argued that explanations of diachronic changes must not stand in conflict with what is known about the human Language Making Capacity in general and, more specifically, about the Language Acquisition Device and the principles constraining acquisition. But although the individual is hypothesized to be the locus of change, it is argued that adequate accounts of diachronic change cannot ignore the fact that speakers share their linguistic knowledge with other members of speech communities. The main question pursued in this book is how core properties of grammars change, i.e. those aspects of grammars which have been shown to be most resistant to change. In the theoretical framework adopted here, this concerns principles constrained by Universal Grammar (UG), most importantly syntactic parameters.

This chapter begins with a brief summary of the evolving professional perceptions and laws relating to juvenile suspects. Recent research differentiates the developmental characteristics of juveniles from adults, including their capacity to reason, sense of time, orientation to the future, and vulnerability during Miranda warnings. This chapter describes voluntariness issues in two murder cases of juvenile suspects. In one case, linguistic analysis compared the juvenile’s language with that of the confession statement he signed, concluding that it was not within the juvenile’s language capacity. In contrast, analysis of the interviewer’s language matched the language of the confession. In the second case, the police decided not to record the interview of the juvenile. They interpreted his answers when they talked with him, producing language that was not close to the suspect’s repertoire.