Darwin's Contribution

My first post of 2009 is about Darwin because this is Darwin’s year and Darwin is central to three issues that are critical to this blog. He was the first modern thinker about human origins, the similarity between biological and linguistic evolution, and the details of how natural selection works. Taken together these areas have given us a new way of thinking about the foundations of human speech, and changed the kinds of questions we ask about human origins. None of the questions that direct this blog were even possible before Darwin:

1. What in the chimpanzee/human lineage provided a foundation for speech?
2. What had to be introduced into the lineage to make speech possible?
3. What, if anything, came out of that process that made us radically unlike other animals?

A Foundation for Speech

The non-Darwinian approach to language’s foundation is to look at language and determine what seems fundamental. A variety of solutions have been offered: language rests on symbolic thinking, language rests on syntactic rules, it rests on phonology, etc. One striking aspect of all these answers is the way they report something not found in other species. In pre-Darwinian thought, an answer has to focus on what is unique or else it cannot get at the core of language, because after all language itself is unique to our species.

The Darwinian approach turns this thinking on its head and asks the first question on this post: What in the chimpanzee/human lineage provided a foundation for speech? Radical as Darwin was, he did not overturn the old saw, you can’t make something out of nothing. There must have been something in the pre-human lineage that could serve as the foundation for speech. Two popular candidates are the perception and navigation systems. The navigation system seems to be based on perception, so it is not truly  an alternate choice. On this blog I have moved with greater and greater confidence toward the idea that speech rests on a modified perceptual system.

That idea leads to unusual definitions—words are pilots of the attention; sentences create a gestalt—that only work in an evolutionary context. (See: What I’ve Learned About Language; Gestalt Linguistics; Attention! It’s A Revolution). The definitions themselves may have been worked out by thinkers who did not ask Darwinian questions, but they can gain followers only by refuting the pre-Darwinian assumption that the foundation must be completely unlike what we find among the apes and other animals.

A Novelty for Speech

The second question—What had to be introduced into the lineage to make speech possible?—might seem to be the point where the pre-Darwinian foundations like symbols and syntax can be introduced, but we can’t change the subject like that. We know that our bipedal walking rests on the pre-bipedal skeleton. What had to be introduced were changes in the skeleton. The logic of linguistic evolution flows the same way. If we say that language rests on the pre-linguistic perception system, we have to keep our eye on the ball and ask what changes had to be introduced into the perception system to enable language?

The answer that has developed on this blog is that we had to become interested in what others perceived and willing to share what we perceive with others.

There is no reason to assume a priori that human perception is sharper or quicker than ape perception, or even that individual humans are smarter than individual apes. The really new feature is the way we engage in joint attention and share our knowledge with others. That communal sharing permits speech, and the whole array of cultural oddities that result from shared activity.

None of this reasoning is to say that symbols, syntax, and a phonological apparatus are not important and did not have to evolve, but they are sub-plots in the larger Darwinian story which is a tale of, as Darwin himself put it, “descent with modification.”

The Radically New

Every species is unique, but most are familiar. Humans see themselves as “the paragon of animals,” but has anything radically new emerged? The pre-Darwinian answer could be religious—humans are unique for their knowledge of good and evil—or secular—humans are unique because of their power of reason. It is amusing to note that the religious assertion now carries more credibility than the secular one. A sense of community obligation—which underpins all morality—is a requirement of a species dependent upon sharing perceptions.

There is also a post-Darwinian answer. The capacity to share perceptions and use what each other knows has given us a radically new kind of time. The theory of evolution based on natural selection famously kicked design and determining cause from the story of origins, replacing it with chance and time. Physicists are puzzled by time because it “moves” only in one direction while their laws don’t require such constancy. For biologists, however, time is their field’s essential ingredient.

Drawing on the geological work of his generation, Darwinian theory gave us the notion of evolutionary time—spans so enormous that chance and survival alone are sufficient to modify species and adapt to changing circumstances. Pre-Darwinian thinking about humans dealt with historical time. Western thought has been marinated in the notion of historical time, which is as like and unlike geological/evolutionary time as a tennis ball is like and unlike the earth. The scale is radically different and the surface of the ball is less varied. Human beings throughout human history are fundamentally similar, which is why the great themes of literature are constant across time and civilizations. We can recognize ourselves in the Bible, in Herodotus, and Thucydides. Evolutionary time erases those themes. Chimpanzees have nothing to learn from and nothing to recognize in The Iliad, but people have recognized themselves in it for 28 hundred years. It took evolutionary time to develop the capacity to make those themes universal across the species.

So, although historical time is much more familiar to us than evolutionary time, the story of all other species is told in evolutionary time. How did historical time enter our story?

It is often said that humans have put biological evolution behind us, which is absurd. We can no more put that behind us than we can exempt ourselves from the law of gravity, but we have added something new to our experience. You can see what I mean by contrasting linguistic evolution with biological evolution. Darwin was fascinated by the comparison between language change and species change (See: Darwin on Language). The two processes share many similarities, but one critical difference is the time element. Human culture, including language, evolves at a much faster rate than the species. Familiar as the fact sounds, it is no small thing. Reducing the time factor reduces the role chance has to play so something besides natural selection has to be part of the story.

“Survival of the fittest” in natural selection means survival of those most able to produce descendants. Usually that means survival of those that are best able to feed and mate. Linguistic fitness usually means survival of those that words and phrases that are most apt to circumstances. Linguistic change includes random drift of sounds, meaningful coinages of words, changes in grammatical structure, and expressive innovations that enable people to speak about things previously unmentioned. In all these cases the changes endure because they are apt.

I am quite sure that apt selection is peculiarly human even though its ins and outs are still quite mysterious. We know it works too quickly to be random and purpose-free and, thanks to Darwin, we know that such selection is a profound wonder.

Comments

[JoseAngel]

A great post, with sweeping and clarifying vistas.
There's another dimension to linguistic selection, which is of course the growth and disappearance of languages. Although the "survival of the fittest" theme is obvious enough, it also shows the complexity of the issues involved. It is not grammatical fitness that is involved, but a whole array of historical and cultural circumstances involving civilization, economic stability and expansion, and a whole historical process. I suppose any evolutionary process studied in its contextual thickness and detail will be just as complex, which doesn't mean of course that significant tendencies and guiding processes shouldn't be highlighted.

[Elizabeth Barrette]

When I think about Darwin's research in conjunction with linguistics, it makes me consider the situation just before language emerged...

The capacity for language had to be present in order for language to exist. So, how long did the capacity exist before the language actually manifested?

Did language emerge pretty much all at once, as an ephiphany, in the style of "punctuated equilibrium" -- one generation, humanoid ancestors, and the next, talking humans? (The novel Darwin's Radio did a wonderful exploration of this.) Or did it evolve gradually, a slow expansion of animal sounds to express ever-more-complex concepts?