How Can Ten Fingers Shape a Pot? Evidence for Equivalent Function in Culturally Distinct Motor Skills

Abstract

Behavioural variability is likely to emerge when a particular task is performed in different cultural settings, assuming that part of human motor behaviour is influenced by culture. In analysing motor behaviour it is useful to distinguish how the action is performed from the result achieved. Does cultural environment lead to specific cultural motor skills? Are there differences between cultures both in the skills themselves and in the corresponding outcomes? Here we analyse the skill of pottery wheel-throwing in French and Indian cultural environments. Our specific goal was to examine the ability of expert potters from distinct cultural settings to reproduce a common model shape (a sphere). The operational aspects of motor performance were captured through the analysis of the hand positions used by the potters during the fashioning process. In parallel, the outcomes were captured by the geometrical characteristics of the vessels produced. As expected, results revealed a cultural influence on the operational aspects of the potters’ motor skill. Yet, the marked cultural differences in hand positions used did not give rise to noticeable differences in the shapes of the vessels produced. Hence, for the simple model form studied, the culturally-specific motor traditions of the French and Indian potters gave rise to an equivalent outcome, that is shape uniformity. Further work is needed to test whether such equivalence is also observed in more complex ceramic shapes.

When handicraft experts face novelty: Effects of shape and wheel familiarity on individual and community standardization of ceramic vessels

“…The finding that neither in Experiment 2 (unfamiliar shapes thrown with familiar wheels) nor in Experiment 3 (unfamiliar shapes thrown with unfamiliar wheels) the mass of clay used to throw the vessels affected the degree of standardization of assemblages may appear surprising at first. As reported earlier (Gandon et al 2011(Gandon et al , 2013, in the present study the use of larger quantities of clay resulted in larger vessels. Because larger vessels are more difficult to throw (Roux and Corbetta 1990) one might have expected a lesser degree of standardization.…”

Individuals Among the Pots: How Do Traditional Ceramic Shapes Vary Between Potters?

“…Next, the profiles were resampled to generate an equal number of points (256 in total) at regular height intervals along the (vertical) y-axis and finally the coordinates were smoothed with a low pass filter (cf. Gandon et al, 2013;Gandon, Coyle, & Bootsma, 2014). Because wheel-thrown vessels are typically axisymmetric, profiles were subsequently converted to full pot outlines by multiplying the x coordinates by -1 to create the corresponding left edge.…”

“…As a widespread, traditional, and artisanal skill, wheel-throwing provides an excellent model for analyzing the cultural transmission and evolution of motor skills and their ensuing artifacts (Gandon, 2014;Gandon, Bootsma, Endler, & Grosman, 2013;Gandon, Coyle, & Bootsma, 2014;Gandon, Roux, & Coyle, 2014). Starting with a formless lump of clay, the goal of wheel-throwing is to produce a pot-of a shape and size chosen in advance-using a wheel rotating in the horizontal plane at speeds varying between 50 and 150 rotations/min (Gandon, Pous, Coyle, Buloup, & Bootsma, 2011;Pierret, 2001;Rye, 1977).…”

Traditional craftspeople are not copycats: Potter idiosyncrasies in vessel morphogenesis

“…The profile coordinates were converted from pixels to centimetres using a calibration factor obtained from the digitized dimensions of the calibration object. The profiles were re-sampled to generate an equal number of (256) points at regular height intervals along the vertical (Y) axis and the resulting coordinates were smoothed with a low-pass filter [13,54]. Because wheel-thrown vessels are typically axisymmetric, profiles were subsequently converted to full pot outlines by multiplying the horizontal (X) coordinates by -1 to create the corresponding left edge.…”

“…In the case of wheel-throwing the formal aspects related to the elementary gestures notably include the hand positions successively used in fashioning a vessel. These hands positions do not determine the manual pressure forces exerted and thereby the vessel shape [13]. Yet, as revealed by personal ethnographic observations in different potting communities, mentors typically encourage their apprentices to carefully watch the hands positions used so that they can reproduce them.…”