Saturday, November 16, 2013

The First Word

The First Word

The Search for the Origins of Language

Viking Penguin 2009

Written by Christine Kenneally
Summarized by Roberto Wissai


The following are verbatim notes of the above book, interspersed with my occasional (mercy!) personal comments and headings. 

A. The wonder of wonders

Ordinary humans flock to sport stadiums and rock concerts and shows. They ooh and aah over displays of fireworks in the evening of the Fourth of July. They are affected by sights and sounds, but are not terribly interested in the how and why of being so. Some humans are definitely not ordinary. They are more cerebral. They want to know why. They are not content to lie back and passively enjoy the pleasures generated by pleasant sights and sounds as the former and larger group. They want to know the why and how of things and processes around them. They are inquisitive. They have an inquiring mind. But unlike the masses, they don't read the National Inquirer. They read the New York Times and the New York Review of Books. Among the things they want to know is how language, possessed only by humans, happened. They generally are also more effective users of language and are bilingual or more. Language fascinates them. They look at those benighted souls with incredulity and askance and a touch of disdain, who ask questions like "what are you going to do with the language that you're learning? Are you going to make money with it?" These folks don't know that for some humans, they climb Mt Everest because it is there. It poses a challenge, not because they hope to make any money with their efforts. In fact, they spend a lot of money just to meet the challenge. The following are the recap of the efforts of those humans who spent time wondering about the wonder that only humans, possess: language. 

The wonder started with a realization that no chimpanzee, Man's closest relative, ever struts to and fro in front of his assembled fellow chimps, and gives a fiery, long speech full of sound and fury, with facial and manual gestures galore while his fellow primates just sit there in rapt silence. Chimps vocalize, hoot and grunt, but only for a short time, and not in front of a large group of silent, enraptured fellow chimps. Their vocalization is not considered language. Neither are the bird songs, whale songs, and dolphin's sonar sounds. Only humans have language. 

B. All languages are complex systems. Yet amazingly by the age of three, children master complicated grammars without any formal instruction. 

Stephen Jay Gould thought language was an evolutionary accident, not an adaptation. 

Norm Chomsky, a titan in linguistics,  held that language is a uniquely human ability, hardwired into our genes with predetermined rules of grammar to make it work. Any attempt to trace language as an evolutionary development was considered suspect, if not impossible, as there were no fossils or other forms of primitive recording to leave their shadowy traces through the ages. 

Chomsky, in a series of email with Steven Pinker and Paul Bloom after these two wrote a paper in 1990 advocating there must be adaptation and natural selection in regard to language evolution, said that he was not opposed to the idea that language evolved, but had great reservations about what he called language---the unique mental syntactic component---originated in the act of communication. He thought there were factors in evolution other than natural selection, which were as likely to be significant. 

Pinker and Bloom believed that just as the eye evolved to meet the need of seeing, language evolved to meet the need of communication. The survival values of language as a tool for our kind of communication are as obvious and profound as the survival advantages of our kind of vision. After the paper published in Behavioral and Brain Sciences, it made a powerful impact. More and more scholars stopped asking, "Did language evolve" and instead wondered, " How did language evolve? Instead of treating it as an indivisible mystery, the problem of language evolution began to fracture into many good and answerable questions, like "What does gesture have to do with language?" How did categorical perception evolve?" "What's the relationship between music and language?" 

Philip Lieberman argues that you cannot understand language if you don't start with evolution. He's fond of Dobzhansky's saying "nothing in biology makes sense except in the light of evolution." In his book, The Biology and Evolution of Language, he argues against linguistic saltation. He cited Darwin's discussion of the evolution of lungs from swim bladders, "an organ originally constructed for one purpose, namely flotation, may be converted into one for a wholly different purpose---namely respiration. Lieberman stressed that he was not arguing that there was no uniquely human specialization for syntax, but rather, his point was that there was an overlap between the parts that control bodily movements and the parts that allow us to order thoughts and words in cognition and speech. The physical overlap had come about because of the way we had evolved, first developing the ability to physically move our bodies in space and then, overlaid upon that, developing the ability to move words in their heads (in abstract patterns). 

Pinker and Bloom believed that Darwinian evolution and Chomsky's universal grammar were compatible, and sought to prove both Darwin and Chomsky were right. L, on the other hand, believed the incongruity between slow evolutionary change and an innate language specific organ was irresolvable. 

When Lieberman began working at Brown University in 1976, he turned his attention to the connection between higher levels of language and the motor system. He started with basal ganglia. These neural structures, the striatum and the globes pallidus, lie beneath the cortex, the brain's outermost rind. The basal ganglia are responsible for learning patterns of motor activity---playing tennis, dancing, picking up a cup of tea. They also control the way different physical movements or mental operations are ordered, one dance step after another, and they are crucial in responding to a change in the  direction of movement or thought. In Parkinson's disease, the brain progressively degenerates, and among the hardest and earliest-hit structures are the basal ganglia. When the cortex is damaged, the patient falls victim to dementia. People suffering from Parkinson's have tremors and rigidity and repeated patterns of movement. What intrigued Lieberman about these people was that they also had trouble comprehending and producing syntax. In addition to showing their physical symptoms, they tended to produce sentences that were particularly short, with only simple syntax. This was a smoking gun for a biological relationship between language and motor control. 

Lieberman moved on to explore the basal ganglia with mountain climbers, Lieberman showed that the farther up the climbers went, the less oxygen they breathed, and just like Parkinson's patients, they became less adept at distinctly pronouncing sounds like b and p, and they took longer to understand test sentences. 

Basal ganglia motor control is something humans have in common with many animals. When we deploy syntax, Lieberman argued, we are using the neural bases for a system that evolved a long time ago for reasons other than stringing words together. The fact that a number of different animals use the basal ganglia for sequencing, whether for grooming or words, said Lieberman, suggests that there is no innately human specialization for simple syntax. Instead of being a contained and recent innovation in the human lineage, the foundation of syntactic ability is an adaptation of our motor system, a primitive part of our anatomy. 

In Lieberman's view, language is not so much a new thing that humans have as a new thing we do, and we do it with a collection of neural parts that has long been available to us. When you think about language this way, it is not really a "thing" at all but a suite of abilities and predispositions, some recently evolved and some primitive. The many parts of the brain and body that make up the language suite allow us to program into our own heads how our parents speak. When Lieberman calls language part-primitive and part-derived, he echoes Darwin, who wrote in The Descent of Man that language was half art and half instinct. 

C. Homology and analogy

One way biologists measure traits is by asking if they are shared among animals. If a trait is shared by two or more species, the next question is if the relationship is homologous or analogous. If the traits are homologs, then they have a common ancestor, which had the same trait. Human arms and bat wings are homologous. 

If the trait is an analog, then even though it is shared by different species, the trait evolved separately in those species. Biologists say that these species have converged upon a similar solution to a problem. Bat wings and butterfly wings are analogs. 

D. Language and Thoughts

Ray Jackendoff, a linguist at Tufts University , said, "Language does help us think better. It does not enable us to go from zero to actual thought. Monkeys do have thoughts, and you have to have something to say before there is something adaptive in saying it." Jackendoff outline four logical possibilities for thinking about language evolution. 

1. Some things that are necessary to language must have undergone to change at all from our pre-linguistic ancestors. Lungs and the basic auditory system belong in this group. 
2. Second, certain traits have appeared only in the human lineage, are relatively new, and are necessary for language but also serve a larger function. This group includes phenomena like pointing and the ability to imitate. 
3. Third, there are probably aspects of language that only humans have and to imitate. 
3. Third, there are probably aspects of language that only humans have and that are used exclusively for language but are based on some alteration of a shared primate trait, like the shape of the vocal tract. 
4. Fourth, parts of language may be used exclusively for language and arise from a trait that is completely new and unprecedented in the lineage we share with other primates. 

In a paper he co-wrote with Steven Pinker, Jackendoff described many ways of thinking that are not possible without language. These include time, fatherhood, moral concepts, tools made of three parts or more, ideas and systems of thought like the supernatural and formal and folk science, and kinship systems that make complicated distinctions like cross-cousins (mother's brothers's child, father's sister!s child) and parallel cousins (mother's sister's child, father's mother's child).
 
The question of whether language can affect the way we see or think about the world has long been controversial in mainstream linguistics. Edward Sapir and Benjamin Lee Whorf, two linguists working in the early part of the 20th century, first popularized the notion that a specific language can shape thought in a particular way. But in the Chomskyan era their theory fell out of favor. It was assumed instead that thought is structured by universal grammar, the core set of linguistic principles all humans share. However, according to Lupyan, "What we are now learning is that besides communicative function, language seems to alter how the brain processes it. Individuals, like stroke patients,who suffer from aphasia do not just find it more difficult to communicate; they also find it more difficult to categorize, remember, and organize information. This is evidence that language plays a role in these cognitive tasks." 

E. Structure

Human language involves two types of structures. In the first, elements from a finite set of meaningless sounds are combined into meaningful words and parts of words, known as morphemes. In the second type of structure, words and morphemes are combined into phrases. This is what linguists call syntax. Both structures have been found not to be restricted to humans. But other animal vocal communication (bird songs, whale songs, primate vocalizations) not only does not have the range of the distinct sounds of human language, ít doesn't appear to employ anything like the number and range of rules that we have for combining speech sounds. 

Of the two types of structures, syntax have been the more hotly contested in the language evolution debate. At its most basic, syntax is a series of rules for combining words in a meaningful way. Until very recently, it was believed that only we could understand or deploy any of the structural devices found in the human syntax, but the pygmy chimp (bonobo) Kanzi showed that this is not entirely the case. Different types of syntax have been observed in the communication of a number of primate species. The simple structural rules that these primates use in the wild contradict the idea that creating meaning with structure is a special human ability. Though there remains a wide gulf between what we do with structure and what other animals do, at least some elements of our ability seem to be graded. 

In his book The Symbolic Species, Terrence Deacon proposes that various platforms of understanding are necessary for an animal to use utterances symbolically. He invokes three types of reference described by C .S. Peirce---ironic reference, indexical reference, and symbolic reference. These distinctions are not inherent to any object or event in the world, but rather descriptions of the kinds of interpretations that can be made about objects or events. Much animal communication makes extensive use if iconic and indexical reference, but only human language is rooted in the complicated relationships that exist with symbolic reference.  

Another domain in which humans use structure with virtuoso abilities is music, which is, like language, one of the species' relatively few universalities. Without formal training any individual from any culture has the ability to recognize music and, in some fashion, to make it. Why this should be so is still largely a mystery. 

F. Human Brain

The potential number of connections between neurons is around 500 trillion. As recently as 25 years ago, it was thought that language specifically resided in Broca's and Wernicke's areas on the left side of the brain. Now we realize that language function is spread throughout the brain. We now realize that brain areas that are active in learning languages are different from the ones that are active when using language once it has been learned. Moreover, different areas are activated depending on the specific language activity, like comprehension of words, categorizing a word (in a new task versus a learned task), translating between languages, or making decisions about grammar . Modern brain imaging has also revealed that the spread of language activation across the two hemispheres of the brain can differ substantially for each individual. 

Brain's plasticity means that the early specialization of human brain tissue does not have to be its ultimate destiny. This plasticity applies not just in what the brain can do but in how it is organized. 

Plasticity is not just a human trait. Greenough at UCLA showed that dendrites and synapses of rats and hamsters change when the creatures are placed in a stimulating environment.

In absolute tens humans don't have the largest brains (whales do) . We have the biggest brain size to body size ratio, called encephalization quotient (EQ). 

G. Human Mutations

All of us alive today share at least one grandmother who lived 150,000 years ago in East Africa. We also share at least one grandfather, an African who lived 60,000 years ago. 

So  far, from a study of a KE family in England whose 14 out of 29 members spreading over 3 generations having speech impediments, it was discovered that the FOXP2 gene located on chromosome 7 was linked to an inherited speech disorder. If an individual has 2 normally functioning copies of  FOXP2, his brain and language will develop normally. If he has only I working copy, he is going to have an array of difficulties with language and speech. No living individual with 2 malfunctioning copies of FXOP2 has ever been found. The core deficits of the FXOP2 gene have much more to do with speech and articulation than with the more complex aspects of language.  After the discovery of FXOP2's language effects, Steven Pinker hailed the possibilities for a new science: cognitive genetics. Vargha-Khadem and her colleagues called it neurogenetics. Whatever this new field ends up being named, the next century will be an exciting time of determine the closeness of the weave of genes, brains, and behavior. The old nature-avers us-nurture debate will finally be shucked off and left behind. 

Language is unique in that there are no other animals with which we converse, no matter what language we are speaking. 

Like biology, language is constituted of an aggregate of different traits and processes that have developed over time. There was no one moment at which humans became definitely human, just as language did not appear from thin air. As important as the shared traits that we use as the basis of language are, so too are the parts that are different. In the end, you have to be human to have human language. 

H. Evolution of the Species

Our direct ancestors left Africa around 60,000 years ago and, after taking thousands of years to reach Europe,, coexisted with the Neanderthals there, until the latter died out 28,000 years ago. Another cousin, Homo floresiensis, lived on the island of Flores in Indonesia were mini-hominids who died out about 13,000 years ago. 

Homo sapiens emerged as a single small population around 200,000 years ago in  Africa. They remained relatively stable for around 100,000 years. Then, between 60,000 and 80,000 years ago, there was a dramatic expansion of certain genetic lineages in the African population. At the same time there was a striking change in technology and culture. 

Some small groups of Homo sapiens left Africa and settled in places like Israel 100,000 years ago, but all of there colonies eventually died out. Our direct fathers and mothers left Africa only 60,000 years ago, soon after their cultural and technological shift, and they successfully introduced their new way of living everywhere they established a foothold. Everybody alive today descended from this small band of travelers. 

As humans spread across the globe, their material and symbolic culture grew richer. By the 40,000-year mark, Homo sapiens were sculpting from stone, painting in caves, and creating a greater variety of musical instruments and jewelry. They were also ritually burying their dead with grave goods, suggesting that they could imagine a place after death where those items might be useful. 

After settlers arrived in Europe 40,000 years ago, it took some 30,000 years to invent agriculture. For modern humans, unlike the Neanderthals or any other species on this planet, culture begets more culture. In the last 50,000 years, the innovation and replacement of material artifacts have not just accumulated but continually accelerated. Against this background, there are 2 main theories about the way language evolved, 

The big genetic bang scenario for culture is often associated with the archaeologist Richard Klein. In this view, a sudden alteration in the organization of our brains, probably resulting from a genetic mutation, occurred around 50,000 years ago. This change was the author of all the cultural innovations that followed, as well as the final successful journey from Africa that left humanity spread across the globe. The saltation gave rise to modern language, words and syntax being the cause and the means by which cultural and technological change spread and evolved. Proponents of this theory tend not to consider the cognitive and potentially linguistic capacities of humans from 50,000 years ago within the larger context of prehuman skills. The implication is more that an all---language and culture---sprang from a nothing. 

Others, like Terrence Deacon, take a view that the fact that the largest number of early symbolic artifacts cluster around 50,000 years ago that does not mean humans were not symbol users before then. The absence of evidence is not evidence of absence. Take the case of African Pygmy societies, which leave little more than bone and stone artifacts as traces of their existence, even though their language, cultural traditions, and music are as complicated as those of any iPhone-toting modern person. Deacon thinks that symbol use probably began around the 2,000,000-year-mark, when our ancestors became bipedal---thus freeing up their hands for tool manufacture and for gesture---and their brains expanded significantly. With that expansion came reorganization of the brain as well, and this, argues Deacon, is a more direct proof of the capacity for symbolic communication than what the archaeological record reveals. Thus symbolic language has been accruing from around the time the australopithecines were replaced by the hominids, and in the last 50,000 years it became transformed into its modern incarnation. 

Genetic differences : 1.2% between humans and chimps, 1.7% between humans and gorillas, and 3% between humans and orangutans. Moreover, most of the differences between us and our cousin primates lie in parts of the genome that are not particularly significant, the junk DNA. Nevertheless, these genomes, which look overwhelmingly similar, produce very different animals: humans have language, other primates do not. The differences are not just cognitive. We have AIDS and other apes don't. We have malaria and they don't. We have a doubled maximal life span. We have bipedal walking. And we have a larger and differently proportioned brain. 

I. The Evolution of Culture 

Culture is a group preference for doings a particular way. As preferences accumulate over time, they become traditions, and these traditions are passed down by a group to its descendants. 

Like humans, apes have culture. That these animals use tools and develop traditions demonstrates that it is possible for simple culture and technology to arise in the absence of language. 

Researchers like Simon Kirby at the University of Edinburgh look at the ways in which language is a product of culture as well as biology,, asking not just h it evolves but how it might have evolved itself. 

Jim Hurford, Kirby's thesis supervisor, pioneered the use of computational (computer modeling) approach to language evolution in the 1980's. The technique became popular quickly because modeling proposes to answer such questions as: How did the world okie items that our ancestors used proliferate to become many tens of thousands of words with many rules about how they can be combined today? Why does language have structure, and why does it have its particular structure? How is it that the meaning of a sentence arises from the way it's out together, not just from the meaning of the words alone? 

In just a few years computer modeling of language evolution has produced a plethora of findings that are counterintuitive to a traditional view of language. The most fundamental idea driving this research is that there are at least two different kinds of evolution---biological and linguistic, meaning that as we evolved, language evolved on its own path. 

Kirby and other researchers find one metaphor especially useful for thinking about language : imagine that it is a virus, a nonconscious life-form that evolves independently of the animals infected by it. Just as a standard virus adapts to survival in its physical environment---a complicated landscape that includes the semi-linguistic mind of the infant, the individual mind of the speaking adult, and the collective mind of communicating humans.

According to Terrence Deacon, language and its human host are parasitic upon each other. "Modern humans need the language parasite in order to flourish and reproduce just as much as it needs humans to reproduce". If some global I disaster killed all humans, there would be no language left. If language suddenly became inaccessible to us, perhaps we would die, too. 

The rollover of language change is thousands of times more rapid than biological evolution. We might it difficult to talk with English speakers from a thousand years ago, but we wouldn't have any trouble procreating with them.

J. Why things evolve

There's something a little disingenuous about the insistence that because you can't prove it, you shouldn't imagine it. Imagination is at the core of scientific process. All the tests and experiments mean nothing without the hunch or the story---the hypothesis---that kicks off the process. 

Michael Arbib's approach to language evolution is the opposite of the the traditional Chomskyan one. Instead of emphasizing the fundamental sameness of language in a search for universals, Arbib is interested in the different ways that people solve problems with language. 

The mirror neurons investigated by Arbib led him to an idea that language evolution had to occur in a layering of stages. Arbib calls it an ascending spiral. So far he has proposed about ten different stages, though he warns that even a ten-stage theory is still a long way from accounting for all the steps along the journey to language. 

Initially, Arbib says, our ancestors must have developed a capacity for complex imitation that went beyond that of even modern apes. Beyond that there must have been some kind of gestural protosign that broke through the fixed set of primate vocalizations and supported by the mirror system. Gesture was an ancient scaffolding on which language started to build. You had to use protosign to build the scaffolding, and then sounds became parasitic. Speech did not arrive directly. Pantomime probably provided the crucial bridge from imitation of practical skills to imitation of the skills required for proto-sign (and much later for language). But we didn't become a species that is constantly engaged in pantomime with no speech because humans "aren't very good at recognizing someone else's pantomime."

On the other hand, in an interview Chomsky suggested there had to be point in time when a rewiring of the human brain that allowed people to use recursion took place. Perhaps 60,000 to 70,000 years ago in a small hominid group in East Africa, a single individual was born with a genetic mutation. This mutation would have caused a restructuring of the brain and instantly bequeathed the affected individual with the capacity for unbounded thought. Linguistic communication would not have begun at this moment, because the individual with the mutation was the only one with the capacity for it. But even a slight advantage spreads quickly throughout the population, and after this new rewriting was passed on to the offspring, the entire group would eventually become language-ready. 

Baldwinian evolution: the behavior of an animal actually contributes to the environment in which its genetic evolution is shaped. Lactose tolerance is an example of Balwinian evolution in humans.  The ability to digest dairy products in adulthood is most common in groups of people who have been herding animals the longest. In this case, it's a behavior---herding---not a climatic change or some other environmental shift, that contributed to the selection pressures in which a predisposition for lactose tolerance improved reproductive success.      

Deacon points out that our brains did not get bigger in the australopithecine-hominid transition in the same way the surface of a balloon gets bigger all over. It was the forebrain, particularly the cerebellum and the cerebral  cortex, that ballooned, while the rest of the brain followed the growth rate seen in other primate brains. In order to unwind the ways that language and the brain have co-evolved, you have to look at the parts of the brain that got bigger, and you have to look at how they got bigger. The fact that language arises from dynamically interacting brain regions with their vastly different evolutionary histories (the more primitive and unchanged along with the parts that have shifted more recently) is another reason why we should not think of language, or even other mental abilities, such as mathematics, as monolithic things. Instead, argues Deacon, they arise out of a "delicate balance of many complementary and competing learning, perceiving, and behavioral biases." Further, says Deacon, we should look at the effect of language on the brain, as well as the effect of the brain on language. 

The result of the co-evolution of the human brain and language is that we now have an overall cognitive bias toward the "strange associative relationships of language." In this sense, our whole brain is shaped by language, and many of our cognitive processes are linguistic. What this means, according to Deacon, is that once we have adapted to language, we cannot not be language-creatures. For us, everything is symbolic. 

K. Future of the Debate

The questions that remain most controversial in language evolution are the following:

1. Was there only one crucial gateway to language through which only humans have passed? 
2. Is there anything in the way language is processed by the brain that is unique, rather than a more general form of recognition? 
3. At what points in the trajectory of language evolution had natural selection come into play? Can any elements of the language suite be clearly identified as spandrels?

Language is not a single thing, and getting from no language to modern human language takes many steps. We are the only species that has taken all of these steps. Nevertheless, many other living animals have taken a considerable number of them. 

L. Future of language and evolution. 

Imaging has shown for many higher-level activities, like language, neural activity is distributed across the brain. Although we can now map the brain at it works, we still have no actual idea how it works. How do the neurons do what they do? How do they process, store , and produce language? There is no predetermined meaning inside our heads. Neurons don't contain symbols but may pass on (or may not pass on) activation signals to one another. So how can the patterned flare of electrical charge across our brains mean that we recognize the word "cat," even when it is spoken by one hundred different speakers with their one hundred unique voices? How can we tell the difference between a p and a b when there is no tiny prototype of these sounds deposited in our neurons? 

The brain is not a digital computer anymore. It's sort of a parallel, semi-analog computer. But how does it do these digital things? 

The problem of language evolution is intractable when it is approached from the perspective of a single discipline. We need the synthesized info from neuroscience, psychology, computer modeling, genetics, and linguistics. 

While all living things affect the evolution of other living things simply by virtue of trying to say alive, humans interact with the biological evolution of other species in a much more complex and powerful fashion because of one ability: language. Nothing occurs on the human scale without language. No language means no agriculture, no animal farming, no science. 

Today there are about 6,000 languages in the world, and half of the world's population speaks only 10 of them. The world loses one of its six thousand languages every 2 weeks, and children have stopped learning half of the languages currently spoken in the world. It's been argued that languages are under greater threat than any endangered bird or mammal. 

Summarized by Wissai
November 15, 2013

Wissai

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