The appearance of this article a few days ago reminded me of another article I had years ago about the evolution of language and the act of gesturing and/or throwing as its precursor.
Years ago, I read this article by Michael Corballis in the American Scientist on The Gestural Origins of Language (1999). This position was supported by other articles I read around that time that linked language and gesturing:Chimps Talk with Their Hands
Right-handed gesturing in apes hints at the origins of human language
By Nicole BrananThe origins of language have long been a mystery, but mounting evidence hints that our unique linguistic abilities could have evolved from gestural communication in our ancestors. Such gesturing may also explain why most people are right-handed.
Researchers at the Yerkes National Primate Research Center recently examined captive chimpanzees and found that most of them predominantly used their right hand when communicating with one another—for example, when greeting another chimp by extending an arm. The animals did not show this hand preference for noncommunicative actions, such as wiping their noses. Such lateralized hand use suggests that chimpanzees have a system in their left brain hemisphere that is coupled to the production of communicative gestures, says study author William Hopkins. The same cerebral hemisphere is host to most language functions in humans, which hints that an ancestral gestural system could have been the precursor for language, he says.
That notion is supported by previous studies that have shown anatomical asymmetries in chimpanzees’ brains in areas that are considered to be homologues of human language centers, such as Broca’s area, Hopkins says. “Chimps that gesture with their right hand typically have a larger left Broca’s area, and those that don’t show a [hand] bias typically don’t show any asymmetry in the brain,” he notes.
The idea that language emerged from an ancestral gestural system located in the left brain hemisphere could explain why the vast majority of people are right-handed, Hopkins says. If gesturing was strongly selected for in human evolution, then the fact that most people are right-handed is a consequence of that. This hypothesis challenges the long-held view that the opposite scenario is true: that right-handedness emerged for motor skills such as tool use and that communication built on the developed asymmetry in the motor system later.
"The Role of the Hand in the Evolution of Language: Target Article on Language Origins," 2000;
"Implications of Recent Research on Gesture and Sign Languages for the Gesture Theory of Language Origins," Adam Kendon (lots of papers on this topic)
Read more of this article.The Gestural Origins of Language
Human language may have evolved from manual gestures, which survive today as a "behavioral fossil" coupled to speech
In 1934 the behavioral psychologist B. F. Skinner found himself seated at the dinner table with the eminent philosopher Alfred North Whitehead, and proceeded to explain to Whitehead what behaviorism was all about. Obliged to offer a challenge, Whitehead uttered the sentence "No black scorpion is falling upon this table" and then asked Skinner to explain why he might have said that. Skinner attempted a reply more than 20 years later in an appendix to his 1957 book Verbal Behavior. He proposed that Whitehead was unconsciously expressing a fear of behaviorism, likening it to a black scorpion that he would not allow to intrude into his philosophy. The skeptical reader may be forgiven for concluding that the reply owed more to psychoanalysis than to behavioral principles.
Be that as it may, Whitehead had articulated one of the properties of language that seems to distinguish it from all other forms of communication, its generativity. Whereas other forms of communication among animals seem to be limited to a relatively small number of signals, and restricted to limited contexts, there is essentially no limit to the number of ideas or propositions that we can convey using sentences. We can immediately understand sentences made up of words that we have never heard in combination before, as Whitehead's sentence illustrates. Language also allows us to escape from the immediate present and to refer to events in other places and at other times. We can use language to fantasize, to describe events that have never existed and never will. This remarkable flexibility is achieved at least in part through the human invention of grammar, a recursive set of rules that allows us to generate sentences of any desired complexity. The eminent linguist Noam Chomsky has attributed this to a unique human endowment that he calls universal grammar. All human languages, he suggests, are variants on this fundamental endowment.
There has nevertheless been considerable progress in teaching something resembling language to captive apes. For example, a young pygmy chimpanzee called Kanzi, studied by Sue Savage-Rumbaugh of Georgia State University, has shown an impressive ability to use symbols on a computerized keyboard in a language-like way and even to understand moderately complex commands spoken in English. Nevertheless, the "utterances" that Kanzi produces typically consist of no more than two or three symbols strung together, sometimes in novel combinations, demonstrating a grammatical capacity that approximates that of a two-year-old human. Children go on to acquire a sophisticated, recursive grammar that is far beyond anything Kanzi, or any other ape, has mastered. There is little doubt that Kanzi and other great apes (and perhaps other species such as dolphins) can use symbols to represent actions and objects in the real world, but they lack nearly all of the other ingredients of true language. As Steven Pinker, a psychologist at the Massachusetts Institute of Technology, remarks in his 1994 book The Language Instinct, the apes just don't "get it."
Since the common ancestor of human beings and chimpanzees lived some 5 million years ago, it is a reasonable inference that grammatical language must have evolved in the hominid line at some point following the split from the line that led to the modern chimpanzee. There has been much disagreement as to when this might have happened. Some linguists, such as Derek Bickerton of the University of Hawaii, have supposed that it is impossible to conceive of grammar as having been formed incrementally; it must therefore have evolved as a single catastrophic event, probably late in hominid evolution. Indeed, Bickerton and others have suggested that it may have coincided with the emergence of Homo sapiens in Africa a mere 150,000 or so years ago. It might explain why H. sapiens came to dominate and ultimately replace all other hominid species, such as the Neanderthals in Europe or Homo erectus in Southeast Asia. Philip Lieberman of Brown University has also argued, on the basis of fossil evidence, that the vocal apparatus necessary to support articulate speech did not emerge until late in hominid evolution, and that even the Neanderthals, who survived until about 30,000 years ago, would have been severely challenged vocally. In his 1998 book Eve Spoke: Human Language and Human Evolution, he too argues that it was language that distinguished our own species from all other hominids. Attempts to trace present-day languages back to the original mother tongue (also known as Proto-World) also suggest a recent origin rather than one that antedates H. sapiens.
The position that language is a recent invention begs the question of whether the vocalizations of living primates—the alarm calls of monkeys and the hooting of apes, for example—are in some form related to human spoken language. Presumably our ancestors were also capable of such vocalizations, so why couldn't these calls have evolved into what we recognize as language? The strongest argument against this scenario is that human language and primate vocalizations are fundamentally very different phenomena. As Chomsky observed in his 1966 book Cartesian Linguistics, human speech is unbounded in its capacity to express thought and in its freedom from stimulus control, whereas animal communication systems either consist of a fixed number of signals or a fixed number of "linguistic dimensions," each associated with a nonlinguistic dimension. Peter MacNeilage of the University of Texas at Austin has also noted that primate vocalizations are "holistic," containing a message in themselves, whereas human vocalizations can be combined in novel ways to create a message. In my view, it seems more likely that the call-like vocalizations of our ancestors have persisted in the emotional cries of modern human beings—such as crying, laughing and screaming—rather than in speech.
Yet it is difficult to accept that an accomplishment as complex as human language could have evolved as an all-or-none event—a "big bang," as it were—late in the evolution of our species. Steven Pinker and his colleague Paul Bloom, now at the University of Arizona, argue that it must have evolved gradually, shaped by natural selection. Some primatologists, such as Richard W. Byrne of the University of St. Andrews, argue that the cognitive prerequisites of language (such as the ability to adopt the mental perspective of another individual) are present in the great apes, and they therefore antedated the split of our hominid ancestors from the chimpanzee line, probably by several million years.
How are we to reconcile these alternative perspectives? At least a partial answer is that language emerged not from vocalization, but from manual gestures, and switched to a vocal mode relatively recently in hominid evolution, perhaps with the emergence of H. sapiens. This idea was suggested by the 17th-century French philosopher Étienne Condillac and revived in the 1970s by the American anthropologist Gordon W. Hewes. It has not found general favor among linguists or anthropologists, perhaps because it lacks parsimony and because there is no direct evidence that any of our hominid ancestors gestured rather than spoke. Even so, argument in its favor has continued to grow.
William H Calvin proposed a theory that throwing actions are related to language development and evolution back in the 1990s - here is some of a paper he wrote on the topic.
William H. CalvinRead the whole article."The unitary hypothesis: A common neural circuitry for novel manipulations, language, plan-ahead, and throwing?"
as it appeared in: Tools, Language, and Cognition in Human Evolution, edited by Kathleen R. Gibson and Tim Ingold. Cambridge University Press, pp. 230-250 (1993).Abstract
Plan-ahead becomes necessary for those movements which are over-and-done in less time than it takes for the feedback loop to operate. Natural selection for one of the ballistic movements (hammering, clubbing, and throwing) could evolve a plan-ahead serial buffer for hand-arm commands that would benefit the other ballistic movements as well. This same circuitry may also sequence other muscles (children learning handwriting often screw up their faces and tongues) and so novel oral-facial sequences may also benefit (as might kicking and dancing). An elaborated version of the sequencer may constitute a Darwin Machine that spins scenarios, evolves sentences, and facilitates insight by offline simulation. An example is given of an evolutionary scenario from an apelike ancestor, demonstrating the transition behaviors and growth curve considerations that any such theory needs to have; this particular scenario (involving throwing improvements) also suggests an explanation for the puzzling design of the Acheulean "handaxe."
In considering transitions of organs, it is so important to bear in mind the probability of conversion from one function to another....Charles Darwin, On the Origin of Species, 1859
That evolution, over all-but-infinite time, could change one physical organ into another, a leg into a wing, a swim bladder into a lung, even a nerve net into a brain with billions of neurons, seems remarkable, indeed, but natural enough. That evolution, over a period of a few million years, should have turned physical matter into what has seemed to many, in the most literal sense of the term, to be some kind of metaphysical entity is altogether another matter.
Derek Bickerton, Language and Species, 1990
Introduction
It is traditional to talk about language origins in terms of adaptations for verbal communications, to talk about toolmaking in terms of natural selection shaping up the hand and the motor cortex, to talk about the evolution of intelligence in terms of how useful versatile problem-solving and look-ahead would have been to hominids. But might natural selection for one of these improvements serve to haul along the others as well? Indeed, might some fourth function be the seed from which the others grew? What are the chances of coevolving talk, technique, and thought?Getting "something for nothing" is, I know, profoundly anti-Calvinist. And the Puritan ethic seems to require us to look for a function's antecedents in their usefulness to that very function. But, as the epigram shows, new uses for old things is not anti-Darwinian. Conversions of function can be profound, providing an enormous boost toward a new ability. Capabilities occasionally arrive unheralded by gradual predecessors. In the familiar case of bird flight origins, one observes that it takes a lot of wing feathers to fly even a little. Presumably natural selection for thermal insulation shaped forelimb feathers up to the threshold for flight. Natural selection for a better airfoil shaped feathers thereafter, but the switch-over from the insulation function to the flying function was presumably a surprise, leaving the protobirds to explore their newfound gliding abilities rather as we might try to figure out a holiday gift that arrived without an instruction manual.
Inventions are the novelties in evolution, though you'd think that shaping-up streamlining was what it was all about, when reading most of the literature. But adaptations are only improvements on an existing function; what we're talking about here is the invention itself before streamlining, and that's often a matter of a Darwinian conversion of function. Nature does take leaps, and such conversions of function are even faster than those anatomical leaps envisaged by proponents of punctuated equilibria and hopeful monsters.
Why might we expect one of these hominid improvements (tools, language, intelligence -- and, I might add, accurate throwing and making music) to serve as a preadaptation for the others? First the general reason, then some specific ones.
A more recent article about this appeared in 2003:
Dunsworth, Holly, John Challis, and Alan Walker. 2003. Throwing and bipedalism: A new look at an old idea. In Franzen JL, Dohler M, Moya-Sola S (editors). Upright Walking. Senckenberg Institute, Frankfurt, pp. 105-110.Still, Calvin's The Throwing Madonna remains the reference for a lot of people on this topic. Other people have written on the use of physical space in American Sign Language, a body-based form of language.
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