Language Evolution and Computation Bibliography

The article addresses the issues related to hominins that first embarked upon the language evolutionary trajectory and modality gestural or vocal, used by them. Comparative studies of animal behavior can shed light on these issues provided they follow proper scientific methods. The earliest probable hominin that is well represented in the fossil record, Ardipithecus ramidus (dating to about 4.4 mya), was clearly substantially different from the bonobo, the chimpanzee, or any other primate, at least with respect to locomotor and dental anatomy. Parsimony dictates that any trait present in all descendants of a common ancestor is more likely to have been present in that ancestor than to have evolved separately in each descendant species. In practice, however, a volume of this nature cannot provide an exhaustive survey of the entire animal kingdom. The first article in this section reviews the ape language. It concludes that human-reared and/or trained members of each of the great ape species such as orangutan, chimpanzee, bonobo, and gorilla, have learned to use gestures, tokens, or visual lexigrams. In sum, although non-human primates have often been considered the most intelligent animals, it now appears that many animals are quite smart, and some may rival apes in their language-learning capacities. To date, however, no animal has demonstrated the full range of ape cognitive capacities, and none stands out as a better animal model for language evolution.

This article debates the issues surrounding language or protolanguage and reviews the age-old idea of ape language. Collectively, the studies of the language capacities of the great apes exceed in numbers those of other animals. No matter how sophisticated the cognitive and communicative capacities of other animals may ultimately prove to be, comparative studies of closest phylogenetic kin will continue to provide the strongest evidence of the probable behavioral capacities of the last common ape ancestor, and, hence, of the probable capacities of the earliest hominins. From their inception, ape-language studies have been embroiled in controversies. To some extent, these controversies reflect the differing perspectives of those who hold Darwinian views of continuity between ape and animal minds versus those who adhere to Cartesian traditions of sharp qualitative mental differences between humans and other animals. This review simply describes actual ape behaviors without prejudging their linguistic nature. It does conclude, however, that a number of apes mastered essential components of protolanguage, but none constructed hierarchically structured sentences containing embedded phrases or clauses. This article articulately describes some real-life incidents. Many apes have lived in human homes and/or are trained for various aspects of the entertainment industry. Often, human owners have been convinced these apes understood modern languages. Rarely have these reports been confirmed or negated. A detailed analysis and records of the development of protolanguages concludes this article.

This article reviews recent evidence for advanced, language-pertinent, cognitive capacities in birds and mammals and evaluates the potential suitability of song and other animal vocal behaviors as models for the evolution of speech. Dolphins are extremely vocal, exhibit intelligence across a number of behavioral domains, are highly social, and often cooperate to herd schools of fish. Dolphins can also recognize themselves in mirrors, coordinate body postures and swimming patterns with those of other dolphins, and imitate each other's vocalizations, including unique signature whistles which serve for individual recognition among adults and in the mother-infant dyad. The only other non-primate mammals whose language capacities appear to have been investigated are domestic dogs. Some have also claimed that domestic dogs equal or exceed great apes in social intelligence. It is reported that both elephants and spotted hyenas are unusually intelligent. Elephants remember and recognize by olfactory and visual means numerous conspecifics and classify them into social groups. They also sometimes cooperate to achieve joint goals and seem to understand others' intentions and emotions. Elephants have highly manipulative trunks, use tools for varied purposes, may recognize themselves in mirrors, and may have a stronger numerical sense than non-human primates. They have elaborate vocal, olfactory, tactile, and gestural communication systems and can imitate some sounds.

This article focuses on the evolution of language along with its anatomy, genetics, and neurology. The concepts of instinct and innateness are actually quite useful for describing behaviors that routinely characterize all members of species or at least all species members of specific sex and age classes. Thus, they tend to be favored by scientists with a primary focus on the distinctive behaviors of individual species. To many developmental biologists and developmental psychologists, however, instinct and innateness are fallacious concepts because all behaviors develop through gene-environment interactions. The solution to this dilemma, in Fitch's view, is to abandon the terms instinct and learning in favor of other terms that more accurately describe the phenomena in question, such as species-specific or species-typical to describe behaviors routinely displayed by all members of a species, and canalization to explain the species-typical gene- environment interactions that produce behavioral regularities. From this perspective, language is a species-specific human behavior that is developmentally canalized via interactions of genes and predictable environmental impacts such as typical adult-infant interactions. In sum, evidence indicates that language evolution probably demanded changes in multiple interacting genes and involved expansions in multiple parts of the brain, as well as changes in the vocal tract and thoracic spinal cord.

This article gives an overview on the various brain structures, other than neocortex, contributing to speech and language. The regions of the avian brain which are considered functionally homologous to human neocortex, are nuclear, as opposed to cortical, in their cellular arrangements. The functional significance of nuclear versus cortical neuronal arrangements remains unknown. The intelligence is best measured by ratios that explicitly and/or implicitly discount other neural areas. The most extreme such measure is Dunbar's neocortical ratio that is the ratio of the size of the neocortex to the size of the entire remainder of the brain. The ratio, which is based on the explicit assumption that the neocortex is the primary seat of intelligence, also rests on the implicit assumption that enlargement of non-neocortical brain structures lowers intelligence. The nuclei and basal ganglia contain neurons that are arranged in a non-layered fashion. Such structures may also lie entirely within the brain, and thus have no visible representation on the outer brain surface. The cerebellar lesions can be associated with a much wider range of cognitive and sensory defects, including defects in working memory, procedural learning, syntax, word order, word choice, and autism. The deficits in both the basal ganglia and the cerebellum accompany the orofacial dyspraxia that results from FOXP2 mutations.

This article focuses on the evolution of language over the years. The evidence for primate and human evolution has derived primarily from comparative anatomy and fossil records, although since the 1960s, molecular and biochemical evidences have increasingly been used to delineate phylogenetic relationships among living species and diverse human populations. One of the current research frontiers involves analyses of the DNA of Neanderthals and other fossils. These molecular findings are reviewed by Cann who reports that mitochondrial DNA and the fossil record roughly agree that the phylogenetic split between hominins and panins. It is the earliest possible date for the emergence of protolanguage. Most interpretations of nuclear and mitochondrial DNA suggest that Neanderthal and modern human lineages split somewhere between 270 and 480 thousand years ago (kya), and all modern humans shared a common maternal ancestor in Africa approximately 200 kya. Some mitochondrial DNA data not reviewed by Cann indicates a genetic split between the South African Khoisan peoples and other Africans sometime earlier than 90 kya. The recent nuclear DNA analyses strongly indicate that genetic interchange did occur between modern humans and Neanderthal populations, either directly or indirectly, and, thus, appear to negate completely the strongest versions of the Out-of-Africa model.

Human tool-dependent foraging strategies enable humans to exploit a much wider range of environments, live in larger social groups at increased population densities, reproduce at shorter intervals, and have expanded lifespans and brain size. Language is integral to human tool-dependent foraging. Humans share information about locations of natural resources needed to make tools and about the physical properties and appropriate treatment of technical materials. Foragers also share information acquired during hunting and gathering expeditions. Hominin ancestors embarked upon new non-ape-like foraging strategies by at least 2.63 mya. This included crushing bones to obtain marrow, using sharp-edged stone flakes to cut meat from bones, and, possibly, exploiting underground plant storage organs. Hominins began using fire to cook, and containers to gather and transport food to home bases at some point. They also mastered new social foraging strategies, including male-female food-sharing bonds, and parental and grandparental provisioning of the young. Hominins were using spears and hunting big game by 400 kya. Modern humans were charting lunar cycles and predicting tidal fluctuations by 164 kya, in South Africa, in order to improve the efficiency and safety of shellfish collection. Europeans were predicting and exploiting seasonal migrations of fish and mammals by upper palaeolithic times.

The Oxford Handbook of Language Evolution presents critical accounts of every aspect of the field. The book's five parts are devoted to insights from comparative animal behaviour; the biology of language evolution (anatomy, genetics, and neurology); the prehistory of language (when and why did language evolve?); the development of a linguistic species; and language creation, transmission, and change. Research on language evolution has burgeoned over the last three decades. Interdisciplinary activity has produced fundamental advances in the understanding of language evolution and in human and primate evolution more generally. This book presents a wide-ranging summation of work in all the disciplines involved. It highlights the links in different lines of research, shows what has been achieved to date, and considers the most promising directions for future work.

As the title suggests, this work chronicles the evolution of language with special reference to animals. Most organisms communicate with conspecifics, whether intentionally or not, and such communication encompasses all conceivable mechanisms. Vocal and other sound-based signals, such as clicking wings or legs, are common in animals. Visual signals are also widespread, including those associated with humans and other primates: manual and facial signals, and bodily postures. The volume is divided into five parts. Part I, about insights from comparative animal behavior, examines animal communication systems and cognitive capacities of potential relevance to the evolution of language and speech. Part II, which details the biology of language evolution including anatomy, genetics, and neurology, offers various views of the physical components of a language faculty. Part III is about the prehistory of language, and in particular askes: When and why did language evolve? The text presents current interpretations of the selective events that may have led to the evolution of language. Part IV, is on launching language and looks especially at the development of a linguistic species, and it presents articles dealing with central properties to be accounted for in language evolution, and issues surrounding the forces that shaped the language faculty. Finally, the articles in Part V look at language change, creation, and transmission in modern humans, and this part of the book examines a number of putative windows on language evolution; for instance, modern events involving language emergence or change, for which there exists a reasonably concrete evidence, might shed light on the evolution of language itself.

This article deals with the different views of researchers on the central properties to be accounted for in language evolution. Stephen Anderson presents certain structural regularities become established in the world's languages, including universal properties such as structure dependence. Anderson argues that there is no need to assume a dichotomy between a genetically determined language faculty and a language faculty shaped by external factors, such as functional pressures and the effects of grammaticalization. The language faculty supports the learning of specific kinds of linguistic systems, and it would not be at all surprising if natural selection favored those who were able to acquire language most efficiently. Grammars that are most easily learned will be the ones that are acquired, because generations of better learners also shaped grammars to be more learnable. James Hurford, Michael Corballis, Stevan Harnad, Terrence Deacon, and Robbins Burling investigate what cognitive capacities must have evolved before the evolution of any kind of language. These capacities include the development of meaning (semantics and pragmatics), the origins of grounded symbols, and the ability to learn and store words. Hurford argues that other animals possess at least proto-conceptual categories, which form the basis for conceptual meaning. Animals exhibit planning abilities, have mental representations of territory, and can make calculations based on their knowledge, such as transitive inference.

This article covers the processes of (modern) language creation and change, and the roles played in language evolution by socio/cultural transmission. Bernd Heine and Tania Kuteva report on the uses of well-known processes at work in observable language change to reconstruct a plausible scenario for the development of the earliest languages. Joan Bybee reports on the concept of grammaticalization that refers to a bundle of processes causing diachronic change that are known to occur in all languages. Grammaticalization is posited as a critical driving force in the evolution of language, and grammaticalization theory gives us a scientific tool for reconstructing earlier linguistic states. Paul Roberge argues against the prevailing view concerning the role of child learners in language change in connection with the formation of creoles. He argues that native acquisition of pidgins is not necessary to form creoles, which are full linguistic systems. Roberge compares the factors leading to the evolution of full language from protolanguage with the factors involved in the formation of pidgins and creoles. Susan Goldin-Meadow reports on the theme of language creation. She explores the role of the manual modality when used alongside speech, and then investigates what changes occur when this modality fulfils all the functions of language, without speech. Sign languages are fully- fledged languages, but more primitive gestural communication occurs in homesign systems.

This paper reviews findings on comparative primate and animal cognition. It suggests that although modern human linguistic, cognitive, and motor behaviors differ profoundly from those of great apes, primarily with respect to required mental constructional skills, an early hominin with ape-like capacities could have used non-innate, referential signals. To determine the most probable selective agents that may have motivated these first steps towards language evolution, it is necessary to look beyond the non-human primates to a wider range of animal species. When this is done, foraging adaptations emerge as the most probable selective agents for cooperative breeding and for the cognitive and behavioral suite that would eventually lead to language.