The First Word: The Search for the Origins of Language (32 page)

Controversy over the paper has continued, and typical of the intense debates that Chomsky ignites, there is sometimes more emotion than accuracy about what is at stake. In one presentation at the Evolution of Language conference in Leipzig in 2004, the speaker, generative linguist Frederick Newmeyer, mentioned the article in an aside, remarking that he was bewildered by it. In response, an upwelling of muttering quickly turned into a shouting match. One researcher stood and shouted: “Chomsky says ‘a miracle occurred.’ Read it! He says ‘a miracle occurred.’” Fitch was also in that audience. When he was able to get a word in edgewise, he said, “I’m a coauthor on that paper, and that word did not appear in it.”

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

 

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

 

The first of the remaining questions reveals an odd, almost vestigial, way of thinking about the subject. We are aware by now that approximately twenty years ago language as a whole was seen as a single gateway through which humanity and no other extant animal has passed. In the face of the many arguments and experiments presented in this book, that idea has fallen apart. Language is not a single thing, and getting from no language to modern human language takes many steps. We are the only species alive today to have taken all of these steps—nevertheless, many other living animals have taken a considerable number of them (though not necessarily along the same path). Thus researchers like Irene Pepperberg talk more in terms of a rough continuum between modern animals and modern humans, describing the linguistic differences between them and us as more quantitative than qualitative. Such a continuum doesn’t necessarily reveal genetic relatedness or trace evolutionary history, but rather is based on the existence of similarities and differences of features important to language.

Still, the idea of a single, categorical shift in the language evolution trajectory haunts the new field. In its latest incarnation, the debate is about whether we acquired recursion in a single move, and in doing so, language became what it is today and we became human, unique among all other living animals.
³
As discussed earlier, this notion has been objected to on several grounds, and many issues remain about how human-specific or language-specific recursion is, and indeed how often humans actually use it.

It’s highly unlikely that a discrete feature could comprise the one, big difference between our language ability and that of modern-day chimpanzees, because their status as our closest living cousins is an entirely arbitrary one. We once had many closer relatives, and they have presumably gone extinct for a variety of reasons. Had the chimpanzee, bonobo, and gorilla gone extinct in the last century, our closest comparison would be with the orangutan, which would move the gap to an arbitrarily greater distance. Certainly no scientist has ever suggested that there is a single biological or logical reason for our current degree of uniqueness (or loneliness). Nor is there is anything significant about the human-chimpanzee split that led us to where we are now. Indeed, since our lineage split away from the chimpanzee line, it’s overwhelmingly likely that our australopithecine and then hominid ancestors took yet more steps, moving through a number of forms of linguistic communication before arriving at the most recent stage of language—ours.

Dan Sperber, a social and cognitive scientist at the French Centre National de la Recherche Scientifique in Paris, makes an interesting case for a component of language that probably predates fully modern language but must have evolved after our ancestors split from chimpanzees. Sperber is well known for the theory he and the linguist Deirdre Wilson presented in a seminal 1986 book,
Relevance: Communication and Cognition.
Briefly, relevance theory holds that inference is as fundamental to linguistic communication as the ability to decode the words in a given utterance. For example, the sentence “It is too slow” may convey a variety of completely different meanings, given different contexts. Sperber lists a few of the possibilities: “The mouse is too slow in solving the maze; The chemical reaction is too slow compared to what we expected; The decrease in unemployment is too slow to avoid social unrest; Jacques’ car is too slow (and so I’d suggest we take Pierre’s).”
⁴

Human communication in this view is about one person indicating his or her meaning to another. This can be done in a number of ways—via gesture, pantomime, or a linguistic code. The fundamental principle is that the person doing the listening (or watching, etc.) infers the speaker’s meaning from the signal
and
the context in which it is conveyed. (The relevance of any message results from a shared set of assumptions. It is crucial, for example, that the listener knows that the speaker wants to convey a meaning, also that the speaker knows that the listener knows this; in addition, there is a shared assumption that what is communicated, regardless of the form it takes, makes sense within the context of the communication.)

Sperber and Wilson’s theory effectively crystallized the intuition that the context of language really matters, and since then, depending on their focus, researchers have placed differing emphasis on the relative significance of the pragmatic aspect of an utterance versus its linguistic structure. Regardless of these differences, Sperber makes the point that all the linguistic sophistication in the world won’t make language useful if its users are unable to infer the intentions behind an utterance and appropriately judge the relevance of its context. Likewise, Sperber points out that, compared to humans, chimpanzees have only a rudimentary ability to make inference about the beliefs and intentions of another chimpanzee. The ability to make sophisticated inferences about the relevance of a signal must therefore have preceded the final elaboration of structure in modern language, and it probably came after the split of our lineage with that of chimpanzees.
⁵

It’s not yet clear what type of investigation, experimental or otherwise, may further illuminate the relationship between pragmatics and linguistics in the evolution of language. Nevertheless, Sperber’s broad point is that both must be explored. In addition to the ideas put forth by Terrence Deacon and Michael Arbib in chapter 14, he has offered an excellent candidate for a specifically human precursor to modern language.

If recursion did not transform our six-million-year-old grandparents into modern humans, perhaps it changed ancient humans into us by converting an archaic, simpler language into the version we have today. Is it possible that this is what happened two hundred thousand years ago? Yes. But if so, this shift is only one of many important turning points in the course of language evolution.

Ultimately, the notion that a single attribute will explain why humans are the only living species to have language is as unhelpful in its latest version as in its oldest. There are hundreds of gateways to linguistic communication, and the evolutionary process provides no motivation to hail
one,
distinct from all the others, as more integral to language. The problem “Is there
one
crucial gateway to language through which only modern humans have passed?” may still be much discussed, but in all of its forms, it is truly a nonquestion.

If good science doesn’t focus on
one
stage in linguistic evolution at the expense of all others, it will inevitably highlight only a selection. This is because some steps will be more experimentally tractable, while others will be easier to observe. Some steps will be notable because they preceded or followed a dramatic cultural shift.
⁶
Some may be considered research-worthy because of their extreme remoteness in time, because they result from a human-specific genetic mutation, or because they drove the selection of a relevant mutation. If a stage in language evolution were ever linked to one of the few genes unique to
Homo sapiens,
it would draw enormous interest. Naturally, some steps will just seem more interesting because of what we think they imply about us.

In the current debate, even though different researchers talk in terms of continuity and discontinuity or qualitative versus quantitative differences, there is nevertheless a greater and more important convergence on the same data and some basic concepts. To a large extent, the conflicts noted here are characterized by different emphases and focus rather than by completely opposed ideas. The argument between Pinker and Chomsky and their coauthors about FOXP2 illustrates this rather well. Pinker and Jackendoff argued that the importance of FOXP2 is that its sequence is uniquely human. Chomsky, Hauser, and Fitch discuss FOXP2 in very different terms—the gene that subserves language is shared by many different species and is therefore likely evidence of the broad foundations of language.

Both are right. The shared nature of the gene implies an ancient history and widely dispersed potential for development along the language path. Nevertheless, a uniquely human mutation of FOXP2 has been positively selected in our species within the last 200,000 years. The FOXP2 mutation is a significant twitch on the genetic dial that accompanies the emergence of human language. Beyond this, the individual researcher may decide what matters most to him—the dial or the twitch.

As for whether there is anything unique to language in the human brain, the question becomes complicated by the need to consider the development of the individual, the development of the species, the way that language itself changes through time, and the way that all of these factors interact. What’s certain is that the question no longer makes sense in the terms in which it used to be posed, that is: Is there a specific gene that programs a specific chunk of the brain to be a language processor? Nevertheless, it does appear that language doesn’t just fall out of the adult human brain without some specifically linguistic processes occurring, as shown by the neural route taken by regular past-tense verbs in contrast to irregular ones.

What about the evolutionary processes of adaptation, where a trait evolves for a particular purpose, and exaptation, where a trait that is used for one function becomes co-opted to serve another purpose in later generations? What role have these played in language evolution? For all the furious words expended on the subject, everyone agrees that both processes have had a role. And everyone has acknowledged that communication has to have something to do with language evolution. Regardless, the rapid spread of the human mutation of the FOXP2 gene is definitive evidence that there has been positive selection for a form of gene that had major consequences for language.

It’s not just the genetics that make the spandrel suggestion unlikely. Humans accumulate a great deal of knowledge in their lifetimes. They are also an extremely social species. Could it just be a coincidence that we are able to communicate all that knowledge to other humans? “We’re social creatures,” said Pinker. “We don’t just cooperate with our kin, we negotiate agreements with people that we’re not related to, and societies are formed by implicit social contracts and exchange and understanding. If language was really just a by-product, one wonders why there would be such an amazingly good fit into the rest of what makes us zoologically unique.”

Many exciting angles remain to be further explored—for example, what’s essential to language development and what is helpful but ultimately incidental? Language clearly bootstraps itself from gesture, but does a species have to have gesture to develop some form of language? How many individuals do you need in a species, as well as in a community, for language to arise in the first place and for it to be passed down through the generations and keep evolving itself? If you have to be human to have human language, could another species in different conditions ever evolve a form of language that used enough of the same basic building blocks that we could translate between our language and theirs?

The jury is out on these questions, though there is every reason to believe that the more data that are generated, the closer we will be to an answer. We can expect resolution on how powerful an evolutionary force communication has been and what elements of language it has shaped. In addition, we can hope to know more about how fine-grained the back-and-forth of modification and selection has been. Were some spandrels adopted as a piece into language? Or did some small increase in the power to compute a grammatical relationship arise as a spandrel and then become further elaborated over a long history of adaptation?

If there were a moral to the story of evolution, it would be that meaning is something that happens after the fact. There is no rhyme or reason to the mutations that occur over the evolution of a species. Within the constraints of what has so far developed, genetic mutations are random; it is what the creature does with them that makes them meaningful. Evolution is the opposite of destiny, and because we are creatures of both biological and cultural evolution, where we are going is really obvious only in hindsight.

Certainly, it’s impossible to predict the future of Chomskyan influence. Chomsky is most famous in cognitive science for being the first to point out that language is both extremely complicated and innate. Now the main complications are how language is defined, what the goals of scientific endeavor are, and the strange and enormous sociological phenomenon that Chomsky has engendered.

Within the field of language evolution, Chomsky is associated with the caveat that language may have as much to do with inner speech as it does with communication between two individuals. But the value of this caution is questionable. We all have the sense that words exist inside our heads and that this sensation accompanies thought. But what forms do the words in one’s mind take? How complete or incomplete are mental sentences? How could so subjective an experience even begin to be measured? No researchers have been inclined, or able, to take the basic idea any further than the form in which Chomsky first suggested it.