Breaking Down the Barriers, 1-19 2013-1-050-001-000341-1 The Evolutionary Origin of Language Reconsidered Charles N. Li (李 訥) University of California, Santa Barbara There are markers and processes in hominid’s evolution and cognitive capability that are relevant to the emergence of language. After a long process of creation and concatenation of symbolic signals in their speech, grammatical structures emerged shortly, in a swift, graded and ongoing manner. This dynamic process defies any attempt to impose on it a non-arbitrary discrete marker as the point of origin of language. Key words: emergence of human language, language origin, human evolution, symbolic signals, gesturing, animal communication, grammatical principles, Foxp2 1. Introduction Throughout history, humans have been fascinated with origins: The origin of the universe, the origin of the earth, the origin of life, the origin of human, the origin of language. Unlike the origins of the universe, the earth, life and human, which are consigned to scientific investigation, the origin of language has attracted a good amount of speculations. The earliest one on record comes from the Old Testament, where we learn that a vengeful God punished the people of Babylon for their vanity and disobedience by creating a great diversity of languages. By the 21st century, a new round of speculations on the origin of language and other complex human behavior has prompted the evolutionary biologist, Richard Lewontin, to sound an alarm in an AAAS meeting (Feb., 2008), that research on the evolution of hominid cognition is akin to ‘paleofantasy’. There is no fossil record of human cognition, observed Mr. Lewontin. Even though Lewontin’s alarm is salutary, I believe that the combined advances in the study of fossil records (paleoanthropology), neuroscience, human genetics, animal communicative behavior and linguistics have laid the empirical foundation for mapping out the landmarks, the processes, the time frame and an outline of the evolutionary origin of language. First, several important landmarks in hominid evolution allow us to delimit a period of time during which human language emerged. Secondly, a wide array of research on Charles N. Li animal communicative behavior in the second half of the 20th century has unveiled the fundamental differences between animal communicative behavior and human language, enhancing our ability to infer the transformations undertaken by hominid communicative behavior that led to the emergence of language. Thirdly, archaeological, neurological and human genetic evidence provides a number of clues to the evolutionary processes leading to the emergence of language. Finally, advances in linguistics have elucidated the emergence of grammar, a dynamic process that never ends in a living language. Let me begin by clarifying the genre of modern language that may give us a hint of language at its origin. 2. Modern language and language origin Modern human language has multiple genres, similar to a Linnean genus consisting of different species. These genres constitute a spectrum with graded differences in grammar, organization as well as vocabulary. If we compare the two extremes of the spectrum, their differences, instead of being graded and minor, will appear discrete and significant in myriad ways. At one extreme of the spectrum is the formal written language constructed in sentences and paragraphs, which, at their best, are rendered in logical and coherent arguments or narrative, and composed strictly according to grammatical conventions. In this channel of communication, the linguistic text must bear the entire burden of transmitting information and attaining communicative felicity between the author and the reader. This is the prevalent genre of language in academic research. Educated people favor the formal written language to such an extent that they endeavor, in certain social contexts, to speak in the way they write. At the other extreme of the spectrum is the casual spoken language of pre-literate cultures, or the casual conversation in contemporary social interaction. This genre of language is composed of words, phrases, intonation units, pauses and various inter- jections, where grammatical constraints are far weaker than they are in written text. Unlike a piece of written text which must be self-sufficient for the purpose of proper transmission of information to the reader, casual spoken language can draw on extra- linguistic information in the communicative context. In other words, unlike a written text, which stands alone in the transmission of information, the language of casual conversation constitutes only one of many facets of a communicative context. If one compares the language in a high-fidelity transcript of a session of casual conversation with the written language of an academic paper, one will have the impression that the former looks haphazard, anarchistic and often ungrammatical. It is, therefore, not surprising that educated people in a literate society tend to hold the language of casual 2 The Evolutionary Origin of Language Reconsidered conversation in low esteem.1 To underscore the gulf separating the two opposite ends of the spectrum of language genres, I will point out two pieces of evidence that are relevant to the origin of language.2 First, every human being is genetically disposed toward acquiring a casual spoken or sign language without instruction, whereas no one can make the same claim for the acquisition of a written language.3 To learn to write is an arduous intellectual endeavor that requires long-term schooling. To those who take writing seriously, it is an art and craft to be honed and improved as long as they live. Probably no more than twenty percent of the world’s population is fluent in a written language. But every human is fluent in a spoken language. Secondly, written language was invented five to six thousand years ago. It is a vital invention that has fueled cultural development, because it permits the unlimited preservation and accumulation of knowledge for transmission to future generations. Casual spoken language precedes written language by hundreds of thousands of years. This chronological difference alone is sufficient to compel us to acknowledge that written language is much too far removed from the origin of human language for it to be useful in investigating how the communicative behavior of hominids evolved into language. Casual spoken language is the only conduit through which we may gain some insight into the nature of language at its origin. In particular, we must bear in mind that long before the dawn of civilization, when the behavior of our hominid ancestors was still focused on survival, as it is the case among all undomesticated, non-human animals today, language was the vehicle of communication that elevated humans to the unprecedented position of absolute dominance in the animal kingdom. I have established an understanding of the linguistic base of what we are looking for as hominid communicative behavior evolved toward language, i.e., a communicative behavior that involves linguistic as well as extra-linguistic information, and a linguistic code that is far less grammatically constrained and far more haphazard than formal written language. I will now proceed to ferret out the major landmarks in hominid evolution that are relevant to the origin of language. 1 This low esteem has had immense impact on generative linguistic theory which, at least during its early development, uses, as its empirical base, the genre of spoken language that closely approximates formal written language. 2 There is a significant literature on the differences between written language and spoken language which does not need to be cited here. 3 There is a significant literature on the acquisition of literacy which is beyond the scope of this article. 3 Charles N. Li 3. Hominids evolution and language origin The family of hominids began approximately six to seven million years ago by a group of great apes who descended from a tree habitat to a savanna habitat in Africa. The cause for this habitat change is assumed to be the geological formation of the Great Rift Valley in East Africa. As East Africa began drifting away from the continent because of tectonic movement, creating the so-called Great Rift Valley, the climate on the East side of the valley turned arid. There, tropical forest gave way to savanna and plains such as the Serengeti and Masai Mara. According to this scenario of geological transformation, our earliest hominid ancestors didn’t come down the trees voluntarily. The trees they were living in gradually disappeared. This is the so-called East Side Story in paleoanthropology. The validity of the East Side Story is now being challenged by recent discoveries of six million year old fossils in Chad and Kenya.4 If these fossils turn out to be hominids, the East Side Story will be cast in doubt because both sites of discovery were rain forest habitat six million years ago. Whether or not the East Side Story proves to be a valid hypothesis for our earliest hominid ancestors to descend from the trees, fossil records confirm that the earliest hominids originated in Africa and genetic studies based on the rate of mutation place the emergence of hominids at around six to seven million years ago. The second landmark more or less coincides with our hominid ancestor’s descent from trees. It is the trait that defines the Linnean family of Hominids, namely, bipedalism. All non-human living great apes knuckle-walk. Humans are the only great ape that has the body and brain structure for walking upright. It took about four million years for hominids to evolve into full-fledged bipedalism and its attendant anatomical structures. This evolutionary transformation involves not just the skeletal structure, but also the muscular composition, the central and the peripheral nervous systems. In other words, the emergence of bipedalism coincides with the start of the evolutionary development of the hominid nervous system to beget a larger and more complex brain.