The First Word: The Search for the Origins of Language (39 page)

24. T.W. Deacon,
The Symbolic Species,
214.

25. C. Cantalupo, W. D. Hopkins, “Asymmetric Broca’s Area in Great Apes.”

26. E. Bates, F. Dick, “Language, Gesture, and the Developing Brain.”

Chapter 11. Your genes have human mutations

1. C. S. L. Lai et al., “A Forkhead-Domain Gene Is Mutated in a Severe Speech and Language Disorder.”

2. C. Knight, M. Studdert-Kennedy, J. R. Hurford “Language: A Darwinian Adaptation?” in
The Evolutionary Emergence of Language,
5.

3. The notion of a language-specific gene echoes the idea from chapter 1 that a little speaker or linguist (a homunculus) is inside our heads and it generates and interprets language for us.

4. S. Olsen,
Mapping Human History.

5. S. Wells,
The Journey of Man.

6. This kind of gene is often connected with changes at the level of the whole organism.

7. W. Shu et al., “Altered Ultrasonic Vocalization in Mice with a Disruption in the Foxp2 Gene.”

8. T. E. Holy, Z. Guo, “Ultrasonic Songs of Male Mice.”

III. What Evolves?

1. With all due respect to Neal Stephenson, whose third book in the excellent, epic trilogy
The Baroque Cycle
is titled
The System of the World.
Stephenson’s book draws its title from the third volume of Newton’s
Principia Mathematica, De Mundi Systemate
(On the System of the World).

Chapter 12. Species evolve

1. In 1997, a team led by Svante Pääbo announced it had compared the mtDNA of a Neanderthal with a modern human. The two examples of DNA were so different that they suggest we are a completely different species. Keep in mind the whole genome would need to be compared for us to conclude fully that there is no Neanderthal DNA in the modern human genome.

2. A. Brumm et al., “Early Stone Technology on Flores and Its Implications for
Homo floresiensis
.”

3. Since the initial announcement of the
Homo floresiensis
discovery, there has been considerable controversy of the classification of this creature. Some scientists claim that hobbits were not our cousins in the way that Neanderthals were but that they are the ancient remains of essentially modern humans who were either pygmies (who are known to inhabit the islands) or who suffered from a disease that stunted their growth.

4. P. Mellars, “Why Did Modern Human Populations Disperse from Africa ca. 60,000 Years Ago?”

5. Ibid.

6. S. L. Salzberg et al., “Microbial Genes in the Human Genome: Lateral Transfer or Gene Loss?”

7. H. Teotónio, M. R. Rose, “Variation in the Reversibility of Evolution.”

8. R. Dawkins,
The Ancestor’s Tale,
67.

9. Ibid., 75.

10. It is not clear whether average difference in DNA or expression difference is the more important. In fact, Pääbo and colleagues argued in a 2005
Science
paper that it is a moot point—both phenomena have undoubtedly been important, and most expression differences go back to sequence differences in regulatory sequences or regulatory genes anyway.

11. M. Cáceres et al., “Elevated Gene Expression Levels Distinguish Human from Non-Human Primate Brains.”

12. In DNA, the four bases, A, G, C, and T, are always paired together. T is paired with A, and G is paired with C. There are approximately 3.2 billion of these base pairs in the human genome. Of these 3.2 billion base pairs, said Enard, only 5 percent carry information that’s relevant to the organism. Moreover, there is roughly 0.08 percent difference between all people, so we are all more or less equally related. (In contrast, any two individual orangutans differ much more from each other.)

13. An alternative possibility is that it resulted from the relaxation of a constraint—i.e., do other animals need it in the form they have and we don’t?

14. Another reason that it is tempting to look for a single genetic mutation to explain language and culture is that although we looked the same from about 150,000 years on, the behaviors that we recognize as modern do not
appear
to have sprung forth for a long time, another 100,000 years or so. Perhaps a mutation caused radical rewiring of the brain, and therefore changes in behavior and culture, without necessarily modifying our appearance? There are many reasons why this may not be the case. We may simply have not found the evidence showing that modern culture did begin to emerge around the 150,000-year mark. Moreover, we know that a number of mutations have taken place in this time frame, although we don’t currently have as much information about their effects as the effects of FOXP2. To say that any one genetic change is responsible for all of language and culture is to ignore our broad evolutionary platform.

Chapter 13. Culture evolves

1. E. S. Savage-Rumbaugh, R. Lewin,
Kanzi.

2. K. J. Hockings, J. R. Anderson, T. Matsuzawa, “Road Crossing in Chimpanzees: A Risky Business.”

3. Hunting is probably one of the most baffling examples of complicated, coordinated animal behavior that occurs without the shared planning that takes place in language. Many animals hunt, including our closest relatives, the chimpanzees. How do pack animals act independently but together in the absence of the clear imperatives humans would issue? (Imagine a group of ten humans bringing down a rearing zebra without any verbal communication between them whatsoever.) Some researchers suspect that the “order” we observe in, say, a lion attack is an emergent outcome of individuals acting alone.

4. J. Mercader, M. Panger, C. Boesch, “Excavation of a Chimpanzee Stone Tool Site in the African Rainforest.”

5. J. Mercader et al., “4,300-Year-Old Chimpanzee Sites and the Origins of Percussive Stone Technology.”

6. Carel van Schaik, “Why Are Some Animals So Smart?”

7. John Locke and Barry Bogin explored the importance of life stages of the individual for language evolution. They identify four developmental stages that humans pass through before adulthood, and they link different functions of language to these stages. Only humans pass through all four stages; they are infancy (birth to three years), childhood (three years to approximately six), juvenility (sexual immaturity but independence of others for survival), and adolescence (sexual maturity). The result, say Locke and Bogin, is that the entire course of a human life in its many different phases (rather than, say, just infancy, adolescence, then adulthood) is essential for the evolution of language over time. One consequence of this is that tracking the origin of different life stages in the fossil record can reveal the course of language evolution. See J. L. Locke, B. Bogin, “Language and Life History.”

8. T.W. Deacon,
The Symbolic Species,
112.

9. Ibid., 110.

10. The opposite of a compositional utterance is a holistic one. Said Kirby: “In some sense, noncompositional language doesn’t even have words, or at least not meaningful ones. Compare the following (noncompositional versus compositional):

Hi
versus
I greet you Chutter
versus
I thought I saw a pussy cat Went
versus
walked Bought the farm
versus
Ceased to live”
There is a related debate within the discipline about whether language may have first been holistic and then become compositional or whether it began as separate units that could be combined. It’s an interesting question for which there are no data.

11. Further research could show how complementary the two approaches are.

12. M. H. Christiansen, S. Kirby,
Language Evolution,
chapter 15.

13. Ibid., 277.

14. For more on emergent systems read Steven Johnson’s
Emergence
and Kevin Kelly’s
Out of Control.

15. AIBO owners and researchers all over the world mourned in early 2006 when Sony decided to cancel production of the robot dog. The QRIO was canceled at the same time.

Chapter 14. Why things evolve

1. N. Chomsky et al.,
On Nature and Language.

2. T.W. Deacon,
The Symbolic Species,
184.

3. Ibid., 147.

4. Ibid., 224.

5. Ibid.

6. J. Diamond, P. Bellwood, “Farmers and Their Languages: The First Expansions.”

7. An odd but interesting line of inquiry into the prehistory of language is the work done on click speech sounds that are found in many African languages. Some researchers contend that clicks are extremely ancient in origin and that click languages of today all descended from one of the oldest, if not the first, human language. But there are many issues to be resolved, including the fact that much inspiration for looking at clicks in this way comes from a linguistic analysis carried out by Stanford linguist Joseph Greenberg. Greenberg grouped all click languages together into one language family, yet subsequent analyses have claimed there is little relationship between many of these languages. Greenberg’s classification of the world’s languages, which Luigi Cavalli-Sforza also used in his attempt to trace the history of languages and genes recounted in
Genes, Peoples, and Languages,
is regarded as highly controversial, if not flat-out wrong, by many linguists today.

IV. Where Next?

Chapter 15. The future of the debate

1. D. Bickerton, “Language Evolution: A Brief Guide for Linguists.”

2. Researchers such as Irene Pepperberg, Sue Savage-Rumbaugh, and Phil Lieberman had long proposed that behaviors in other animals, whether they are learned or whether they arise naturally, expand our understanding of language evolution. Moreover, Chomskyan linguistics, if not Chomsky himself, with its emphasis on the innate and uniquely human language capacity, had for many years discouraged researchers from looking to animals for information about human language.

3. Instigated by the Hauser, Chomsky, Fitch
Science
paper, but not necessarily about the specific hypotheses they proposed.

4. G. Origgi, D. Sperber, “A Pragmatic Perspective on the Evolution of Language and Languages.”

5. In a presentation at the 2005 Evolution of Language Symposium at Stony Brook, Sperber talked about the human ability to construct representations of representations—that is, metarepresentations. “A metarepresentational ability,” he said, “need not have communication as a primary function, but it makes inferential communication possible.” He elaborated on this by describing the way the briefest moment of nonlinguistic communication can be built from a complicated layering of inference and shared understanding. For example, when Mary and her son Peter take a walk through the forest they pass a shrub with a kind of berry unknown to Peter, Mary establishes eye contact with him, bites a berry and spits it out, and from this Peter understands that she means that he should not eat these berries. Such communication involves the following layers of representation and intention: “