What follows is a blog post from Eric La Freniere (firstname.lastname@example.org), who is a JMU Graduate Student in rhetoric and communication interested in the evolution of language and human consciousness. We had some interesting exchanges and realized that we shared very similar ideas regarding the nature of culture and human consciousness, connecting the dots from his view of rhetoric and my view of justification. He shared with me his synopsis on the origin of language and slides and I thought they might make for an interesting blog post. Note that Justification Hypothesis is a theory of how the problem of social justification would have altered human self-consciousness and culture. It is not, of course, a theory of the evolution of language itself. This is what Eric is trying to work out.
Preface to a General Theory of the Origin of Language as a Function of Brain Hemispheric Interaction.
Language is a signaling system that involves the abstraction of information from a gestalt field for purposes of representation and communication. But language is contingency-based, as opposed to instinctive, i.e. it allows for the spontaneous creation of recombinative information and thus novel responses across the brain of an individual organism, as opposed to across generations within the gene pool of an entire species. How did language evolve?
By just over 500 million years ago, brains had evolved, and the extrusion of eyes kicked off the “Cambrian explosion,” a positive feedback-driven proliferation of organic complexity involving the emergence of most of the major animal groups existing today—including fish, from which all vertebrates evolved. Fish have non-overlapping vision and optic nerves that cross to connect each eye with the opposite side of the fish brain, which has no left-right neural bridges.
Fish engage their environments according to left-right preferences; for example, fish typically respond more quickly when predators are first seen through one eye, and they forage for food more efficiently when using the other eye (Giorgio Vallortigara has done basic research here). In other words, one eye and its contralateral half of the brain focus on what might be called “retreat” perceptions and behaviors, while the other eye and half of the brain focus on what might be called “approach” perceptions and behaviors. We may say that the retreat brain is neurologically geared towards recognizing changes in gestalt fields to generate more rapid “fight-or-flight” responses, while the approach brain is neurologically geared towards abstracting particular objects to generate less rapid “feed or f*ck” responses. (Note that in its basic form, abstraction simply means to draw or take away, to remove or isolate).
For 500 million years, evolution wrung as much adaptability—as much intelligence—as possible out of the animal brain. Yet for virtually all that vast stretch of time, there is no evidence of tool use or culture, and thus no evidence of language. Nonhuman signaling systems, including complex affective displays, seem largely incapable of recombination; they cannot, in and of themselves, generate novel responses to selective pressures.
Finally, just 2 ½ million years ago, a group of tool-making primates (H. habilis) emerged. They had big brains, but their flaked stone tool kit remained unchanged for hundreds of thousands of years. Then a new group of even bigger-brained primates (H. erectus) began reworking their own stone tools with an eye toward shape and symmetry—but other than that, again, no change for hundreds of thousands of years.
It is unlikely that language was involved in the production of these Lower Paleolithic technologies; the lack of novelty over time suggests a lack of abstract or representational recombination. We are probably looking at the maximum adaptability or intelligence possible through genetic evolution alone: a more-or-less instinctive, tool-using “culture” made possible by a perfect storm of organic factors such as binocular vision, bipedalism, an opposable thumb, complex vocalization, and a big brain. By the Middle Paleolithic, the increasingly expensive primate big brain experiment seemed to have reached its gradualist conclusion (Homo sapiens neanderthalensis).
But evidence indicates that punctuated equilibrium intervened: a hopeful monster was born (Homo sapiens sapiens). Archeologists have characterized the Upper Paleolithic, the period beginning about fifty thousand years ago, as the “creative explosion.” Stone was fashioned into novel shapes for novel purposes, and art emerged, along with the mastery of fire, human burial, and the bone needle for sewing. Language had clearly arrived, but how?
Stephan Gould’s hopeful monster idea suggests that a point mutation (a single base nucleotide replacement in the DNA sequence) could have enabled the emergence of language across the hemispheres of the already-lateralized proto-human cerebral cortex. How did a single mutation make such a dramatic difference? According to chaos theory’s infamous “butterfly effect,” even a tiny initial change within a complex system can result in dramatic differences in eventual outcome. The proto-human brain was the most complex system on the planet; a single mutation could have snowballed change across its entire neurodevelopmental process, from embryogenesis to adulthood.
Our retreat brain—nowadays, usually the right hemisphere—emphasizes gestalts and image-based processing to generate more immediate responses. Our approach brain—nowadays, usually the left hemisphere—emphasizes abstraction and word-based processing to generate more deliberative responses. Although proto-human abstraction had not been spontaneously recombinative, tool use had been gradually priming the pump for a couple million years.
Neurobiologists Roger Sperry and his protégée Michael Gazzaniga pioneered research teasing apart the cognitive differences between the hemispheres of the human cerebral cortex. Through a series of clever experiments involving previously epileptic people whose seizures had been curtailed by the severing of left-right neural bridges, Sperry and Gazzaniga established that the left hemisphere emphasizes relatively linear, logical, focused, grammatical processing functions, while the right emphasizes relatively associative, affective, holistic, contextual processing functions.
Functional lateralization is accompanied by structural lateralization on the molecular, cellular, tissue, and organs levels. The human planum temporale, for example, is a roughly triangular area of the cerebral cortex. On the left side, it is centered in Wernicke’s area—crucially involved in abstraction—and its tissues exhibit wider columns and more neuropil space, resulting in the most significant asymmetry of any brain on the planet: the human left planum temporale can be up to five times as large as the right.
The left hemisphere-centered word, or contingency-based abstraction, is the most distinctive component of the distinctly human signaling system we call “language.” According to Ferdinand de Saussure—a founder of the science of linguistics and was the founder of semiotics, or the study of signs—language is based on signs (which makes sense, since language is a signaling system that involves abstracting information from a gestalt field for purposes of representation and/or communication). For Saussure, every sign has two components: a signifier and a signified.
Here, the signifier is a more or less arbitrary word or contingency-based abstraction—thinks Wernicke’s area (LH)—and the signified is a more or less meaningful image or affectively prioritized sense data—think fusiform facial area (RH). So, for purposes of representation, communication, and recombination, the word/image-conjoined “utterance” (Saussure’s term) is the building block of linguistic vocalization or speech.
Simple nouns and verbs were the most concrete utterances (there is a difference in hemispheric emphasis between those basic parts of speech). They were used to create the primal justification narratives / rhetorical systems that selected (often sexually) for the evolution of ever more abstract nouns and verbs, other parts of speech, and eventually (spurred on by writing) linguistic self-reference, including syntactical-symbolical constructions such as “I Am Who I Am” and “I think, therefore I am.”
Eric La Freniere