A Cognitive Account for Co-evolution of the Stone Tools Making and Word Classes

GUO Chunjie, Nanjing University of Aeronautics and Astronautics

Recent years have seen increasing interest in the research of co-evolution of the stone tools making and language. In a study of Paleolithic technology and human evolution, Ambrose (2001) put forward a hypothesis that complex tool-making, which required fine motor skills, problem-solving and task planning might have influenced the evolution of the frontal lobe, and co-evolved with the grammatical language 300,000 years ago. By conducting a series of experiments in teaching contemporary humans the art of Oldowan stone-knapping, Morgan and his colleagues (2015) arrived at their conclusion that the stone tool-making might generate some selection for teaching and language. A series of brain imaging studies conducted by Stout et al. (2011) have shown that tools making and language use similar parts of the brain, including regions involved in manual manipulations and speech production. Uomini and Meyer (2013) applied a technique called functional transcranial Doppler ultrasonography (fTCD) to subjects in the field to monitor their brains during the vigorous activity of making stone tools, the results offered support for the hypothesis that language and tools making coevolved. 

If it is possible that the stone tools making and human language could have co-evolved in the Paleolithic Ages, then what could have triggered the neurological and cognitive mechanisms for language when our ancestors were undertaking to make their stone tools? What are the common cognitive grounds underlying the production of the stone tools and language (to be more specific, what are the common cognitive grounds in the production of different modes of stone tools and different word classes)? Is it possible for the present-day brain imaging equipments to pick up these cognitive patterns? These questions might offer some help in better understanding the co-evolution of stone tools making and human language in their earliest stages. This paper reports a series of fMRI studies on the neurological and cognitive relationships between the making of different mode of stone tools (Clark, 1969) and the different semantic pattern of word categories (Guo, 2013), in order to provide empirical evidence for the co-evolution of the stone tools making and lexical development in the Paleolithic Ages.

A group of college students are asked to have their brains scanned when they are thinking about stone tools making and the semantic meaning of some word classes. The paper is focused on this question: What are the common cognitive grounds underlying the production of different modes of stone tools and different semantic patterns of word classes? This general question is divided into 4 specific questions: (1) What cognitive properties are required in the production of each mode of the stone tools? (2) What cognitive properties are required in the production of each of different word classes? (3) What are the cognitive patterns in the evolutionary development of the stone tools making and different word classes? (4) Can the cognitive properties and patterns be mapped between the stone tools making and lexical development? The following analytical techniques are employed in the data analyses: analytical induction, cognitive analysis, contrastive analysis, logical analysis, phenomenology, and semantic analysis.

According to cognitive linguistics, human’s language competence is not a specialized innate faculty of the brain, but rather a by-product of a general cognitive development in the hominin evolution. The tempo and mode of the stone tools making can help to interpret the associated cognitive and communicative (i.e. language) development of those tools makers. We argue that cognitive development for language occurs concurrently and is interrelated with the intellectual development for stone tools making. The chief reason why language could have co-evolved with the stone tools making lies in that they require the same or similar functioning in the cerebral and cognitive development. When our ancestors were undertaking to make their stone tools, the intellectual demand for problem-solving, the drive for communications, the coordination between the hand and mind, the need for voicing instead of gesturing in teaching, all this would have triggered the cognitive mechanisms for language.

References

Ambrose, S. (2001). Paleolithic technology and human evolution. Science, 291, 1748-1753.

Clark, G. (1969). World Prehistory: A New Synthesis. Cambridge: Cambridge University Press.

Guo, C. J. (2013). Semantic Studies on Item-Associate Lexicon. Beijing: China Social Science Press.

Morgan, T. J. H., Uomini, N. T., Rendell, L. E., Chouinard-Thuly, L., Street, S. E., Lewis, H. M., Cross, C. P., Evans, C., Kearney, R., de la Torre, I., Whiten, A., & Laland, K. N. (2015).  Experimental evidence for the co-evolution of hominin tool-making teaching and language. Nature Communications. January, 14.

Stout, D., Passingham, R., Frith, C. D., Apel, J., & Chaminade, T. (2011). Technology, expertise and social cognition in human evolution. European Journal of Neuroscience, 33 (7), 1328-1338.

Uomini, N. T. & Meyer, G. F. (2013). Shared Brain Lateralization Patterns in Language and Acheulean Stone Tool Production: A Functional Transcranial Doppler Ultrasound Study. PLoS ONE, 8 (8), e72693.