They are correct that punctuated equilibria apply to sexually reproducing organisms and that morphological evolutionary change is regarded as largely (if not exclusively) correlated with speciation events. However, they err in suggesting that we attribute stasis strictly to "developmental constraints," which represent only one of a set of possible mechanisms that we have suggested for the causes of stasis. Others include habitat tracking and the internal structure of species themselves [for example, (2)].

According to Bickerton, the behavioral sciences have failed to give an adequate account of human nature at least partly because of the conjunction and mutual reinforcement of two widespread beliefs: that language is simply a means of communication and that human intelligence is the result of the rapid growth and unusual size of human brains. Bickerton argues that each of the properties distinguishing human intelligence and consciousness from that of other animals can be shown to derive straightforwardly from properties of (...) language. In essence, language arose as a representational system, not a means of communication or a skill, and not a product of culture but an evolutionary adaptation. The author stresses the necessity of viewing intelligence in evolutionary terms, seeing it not as problem solving but as a way of maintaining homeostasis - the preservation of those conditions most favorable to an organism, the optimal achievable conditions for survival and well-being. The term protolanguage is used to describe the stringing together of symbols that prehuman hominids employed. "It did not allow them to turn today's imagination into tomorrow's fact. But it is just this power to transform imagination into fact that distinguishes human behavior from that of our ancestral species, and indeed from that of all other species. It is exactly what enables us to change our behavior, or invent vast ranges of new behavior, practically overnight, with no concomitant genetic changes." Language and Human Behavior should be of interest to anyone in the behavioral and evolutionary sciences and to all those concerned with the role of language in human behavior. (shrink)

How to point : a primer for Martians -- What it takes to be a pointer -- Do animals get the point? -- People who don't point -- Pinning language to the world -- Pointing and power -- Assisted pointing and pointing by proxy -- The transcendent animal : pointing and the beyond.

It has long been claimed that Homo sapiens is the only species that has language, but only recently has it been recognized that humans also have an unusual pattern of growth and development. Social mammals have two stages of pre-adult development: infancy and juvenility. Humans have two additional prolonged and pronounced life history stages: childhood, an interval of four years extending between infancy and the juvenile period that follows, and adolescence, a stage of about eight years that stretches from juvenility (...) to adulthood. We begin by reviewing the primary biological and linguistic changes occurring in each of the four pre-adult ontogenetic stages in human life history. Then we attempt to trace the evolution of childhood and juvenility in our hominin ancestors. We propose that several different forms of selection applied in infancy and childhood; and that, in adolescence, elaborated vocal behaviors played a role in courtship and intrasexual competition, enhancing fitness and ultimately integrating performative and pragmatic skills with linguistic knowledge in a broad faculty of language. A theoretical consequence of our proposal is that fossil evidence of the uniquely human stages may be used, with other findings, to date the emergence of language. If important aspects of language cannot appear until sexual maturity, as we propose, then a second consequence is that the development of language requires the whole of modern human ontogeny. Our life history model thus offers new ways of investigating, and thinking about, the evolution, development, and ultimately the nature of human language. (shrink)

From the first months of life, human infants produce “protophones,” speech-like, non-cry sounds, presumed absent, or only minimally present in other apes. But there have been no direct quantitative comparisons to support this presumption. In addition, by 2 months, human infants show sustained face-to-face interaction using protophones, a pattern thought also absent or very limited in other apes, but again, without quantitative comparison. Such comparison should provide evidence relevant to determining foundations of language, since substantially flexible vocalization, the inclination to (...) explore vocalization, and the ability to interact socially by means of vocalization are foundations for language. Here we quantitatively compare data on vocalization rates in three captive bonobo (Pan paniscus) mother–infant pairs with various sources of data from our laboratories on human infant vocalization. Both humans and bonobos produced distress sounds (cries/screams) and laughter. The bonobo infants also produced sounds that were neither screams nor laughs and that showed acoustic similarities to the human protophones. These protophone-like sounds confirm that bonobo infants share with humans the capacity to produce vocalizations that appear foundational for language. Still, there were dramatic differences between the species in both quantity and function of the protophone and protophone-like sounds. The bonobo protophone-like sounds were far less frequent than the human protophones, and the human protophones were far less likely to be interpreted as complaints and more likely as vocal play. Moreover, we found extensive vocal interaction between human infants and mothers, but no vocal interaction in the bonobo mother–infant pairs—while bonobo mothers were physically responsive to their infants, we observed no case of a bonobo mother vocalization directed to her infant. Our cross-species comparison focuses on low- and moderate-arousal circumstances because we reason the roots of language entail vocalization not triggered by excitement, for example, during fighting or intense play. Language appears to be founded in flexible vocalization, used to regulate comfortable social interaction, to share variable affective states at various levels of arousal, and to explore vocalization itself. (shrink)

This article takes an evolutionary “reverse engineering” standpoint on Homo discens, learning man, to track down the mechanisms that played a pivotal role in the natural selection of human being. The approach is “evolutionary sociological”—as opposed to gene-centred or psychologising—and utilises notions of co-evolutionary organism–environment transactions and niche construction. These are compatible with a Deweyan theory of action, which entails that in action one cannot but learn and one can only learn in action. Special attention is paid to apprentice-like learning-by-doing (...) peculiar to human socio-cultural niches since the Pleistocene, which has permitted each subsequent generation to learn the many habits and skills needed in utilising the affordances of action that constitute their ecological niche. Affordances and actions have changed over the history of human–environment transactions, but the core mechanisms of human learning have not changed much. It is increasingly important to appreciate these mechanisms now in the global age “knowledge society,” which is in a way similar to the Pleistocene era: characterised by uncertainty and life-determining problem-situations without any ready-made solutions, it calls for capacities to adapt to changing circumstances, and thus apprentice-like learning in action supported by savvy epistemological engineering of learning environments. (shrink)

Primate vocal communication is very different from human language. Differences are most pronounced in call production. Differences in production have been overemphasized, however, and distracted attention from the information that primates acquire when they hear vocalizations. In perception and cognition, continuities with language are more apparent. We suggest that natural selection has favored nonhuman primates who, upon hearing vocalizations, form mental representations of other individuals, their relationships, and their motives. This social knowledge constitutes a discrete, combinatorial system that shares several (...) features with language. It is probably a general primate characteristic whose appearance pre-dates the evolution of spoken language in our hominid ancestors. The prior evolution of social cognition created individuals who were preadapted to develop language. Several features thought to be unique to language—like discrete combinatorics and the encoding of propositional information—were not introduced by language. They arose, instead, because understanding social life and predicting others’ behavior requires a particular style of thinking. (shrink)

In order to formulate hypotheses about the evolutionary underpinnings that preceded the first glimmerings of language, mother-infant gestural and vocal interactions are compared in chimpanzees and humans and used to model those of early hominins. These data, along with paleoanthropological evidence, suggest that prelinguistic vocal substrates for protolanguage that had prosodic features similar to contemporary motherese evolved as the trend for enlarging brains in late australopithecines/early Homo progressively increased the difficulty of parturition, thus causing a selective shift toward females that (...) gave birth to relatively undeveloped neonates. It is hypothesized that hominin mothers adopted new foraging strategies that entailed maternal silencing, reassuring, and controlling of the behaviors of physically removed infants (i.e., that shared human babies' inability to cling to their mothers' bodies). As mothers increasingly used prosodic and gestural markings to encourage juveniles to behave and to follow, the meanings of certain utterances (words) became conventionalized. This hypothesis is based on the premises that hominin mothers that attended vigilantly to infants were strongly selected for, and that such mothers had genetically based potentials for consciously modifying vocalizations and gestures to control infants, both of which receive support from the literature. Key Words: bipedalism; brain size; chimpanzees; foraging; gestures; hominins; infant riding; motherese; prosody; protolanguage. (shrink)

The strong predominance of right-handedness appears to be a uniquely human characteristic, whereas the left-cerebral dominance for vocalization occurs in many species, including frogs, birds, and mammals. Right-handedness may have arisen because of an association between manual gestures and vocalization in the evolution of language. I argue that language evolved from manual gestures, gradually incorporating vocal elements. The transition may be traced through changes in the function of Broca's area. Its homologue in monkeys has nothing to do with vocal control, (...) but contains the so-called “mirror neurons,” the code for both the production of manual reaching movements and the perception of the same movements performed by others. This system is bilateral in monkeys, but predominantly left-hemispheric in humans, and in humans is involved with vocalization as well as manual actions. There is evidence that Broca's area is enlarged on the left side in Homo habilis, suggesting that a link between gesture and vocalization may go back at least two million years, although other evidence suggests that speech may not have become fully autonomous until Homo sapiens appeared some 170,000 years ago, or perhaps even later. The removal of manual gesture as a necessary component of language may explain the rapid advance of technology, allowing late migrations of Homo sapiens from Africa to replace all other hominids in other parts of the world, including the Neanderthals in Europe and Homo erectus in Asia. Nevertheless, the long association of vocalization with manual gesture left us a legacy of right-handedness. Key Words: cerebral dominance; gestures; handedness; hominids; language evolution; primates; speech; vocalization. (shrink)

Th is chapter outlines the theory (fi rst explicitly defended by Pinker and Bloom 1990), that the human language faculty is a complex biological adaptation that evolved by natural selection for communication in a knowledgeusing, socially interdependent lifestyle. Th..

We present an account of semantics that is not construed as a mapping of language to the world but rather as a mapping between individual meaning spaces. The meanings of linguistic entities are established via a “meeting of minds.” The concepts in the minds of communicating individuals are modeled as convex regions in conceptual spaces. We outline a mathematical framework, based on fixpoints in continuous mappings between conceptual spaces, that can be used to model such a semantics. If concepts are (...) convex, it will in general be possible for interactors to agree on joint meaning even if they start out from different representational spaces. Language is discrete, while mental representations tend to be continuous—posing a seeming paradox. We show that the convexity assumption allows us to address this problem. Using examples, we further show that our approach helps explain the semantic processes involved in the composition of expressions. (shrink)

All known chimpanzee populations have been observed to hunt small mammals for meat. Detailed observations have shown, however, that hunting strategies differ considerably between populations, with some merely collecting prey that happens to pass by while others hunt in coordinated groups to chase fast-moving prey. Of all known populations, Taï chimpanzees exhibit the highest level of cooperation when hunting. Some of the group hunting roles require elaborate coordination with other hunters as well as precise anticipation of the movements of the (...) prey. The meat-sharing rules observed in this community guarantee the largest share of the meat to hunters who perform the most important roles leading to a capture. The learning time of such hunting roles is sometimes especially long. Taï chimpanzee males begin hunting monkeys at about age 10. The hunters’ progress in learning the more sophisticated hunting roles is clearly correlated with age; only after 20 years of practice are they able to perform them reliably. This lengthy learning period has also been shown in some hunter-gatherer societies and confirms the special challenge that hunting represents. (shrink)

The origin of human language is one of the most fascinating and most difficult problems of evolution. Here I argue that pre-hunt communication was the starting context of the evolution of human language. Hunting of big game created a shared interest; animals and hunting actions are easy to imitate; the need to plan created a pressure for increasing complexity; and finally, cultural inheritance of hunting tools and know-how made the transition unique. I further argue that this “first step” was actually (...) a two-stage process where first indexical and iconic signs evolved to coordinate recruitment for the hunt; then later, in the second stage, the complexity of this communication system increased as a response to the increased demand to coordinate group-hunting effort (including division of labor). I provide a review of the fossil record and show that the available evidence is fully compatible with the theory. (shrink)