Can individual differences be detected in same-shaped pottery vessels by unknown craftsmen?

Date:
October 27, 2020
Source:
Kobe University
Summary:
Can quantitative differences be used to identify individual potters
who make traditional, fixed-shape vessels that have been made in
the same way for generations? Researchers discovered that there
are clear variations between individuals in the formation process
and hand movements used.



FULL STORY ==========================================================================
An interdisciplinary research team has investigated whether there are quantitative differences that can be used to identify individual potters
who make traditional, fixed-shape vessels that have been made in the
same way for generations. Consequently, they discovered that there are
clear variations between individuals in the formation process and hand movements used.


========================================================================== Members of the research team included Dr. Enora Gandon (Institute
of Archaeology, University College London), Professor NONAKA Tetsushi
(Graduate School of Human Development and Environment, Kobe University),
and Professor Emeritus John A. Endler (Deakin University).

Up until now, the transmission of cultural traditions has been viewed in
terms of 'imitation' and 'transmitted information'. However, the results quantitatively show that other factors beyond imitation, such as the individual's corresponding ability and exploratory learning process,
play a role. In addition, it is hoped that these results will serve as
a basis for determining whether unattributed archaeological artefacts
were produced by one or multiple artisans.

These research results were published in the scientific journal'PloS ONE'
as two separate papers on September 22 and October 1 respectively.

Main Points
* There were quantitative differences distinct to individual potters,
even
when standard traditionally-shaped vessels were produced.

* There was greater diversity between potters during the formation
process
compared with the finished product.

* Multiple hand movement patterns that could be used to distinguish
individual craftsmen were found.

Research Methodology and Findings Humans pass down various skills to
their communities and the next generation.

One of these skills that has been transmitted since ancient times
is pottery.

This study investigated how the individuality of each craftsman stands out during the formation process of traditional pottery pieces, in particular
the standardized, unsigned pottery produced for the mass-market.



========================================================================== First of all, the research team recorded video footage of potters making traditionally shaped pottery in the workshops of two different communities located in the Indian state of Uttar Pradesh (a Hindu community which
uses a hand-operated stick-wheel, and a Muslim community which uses
a foot-operated kick-wheel). The researchers performed an elliptical
Fourier analysis on the recorded images in order to investigate the
shape formation process during pottery throwing.

The results revealed that: 1. There were quantitatively distinguishable differences between the pottery produced by individual craftsmen, even
among standard traditionally-shaped vessels produced for the consumer
market.

2. There was greater variation between potters during the formation
process than in the finished form.

Next, the researchers recorded video footage of traditional pottery
shapes being made by craftsmen in a workshop in Bhaktapur, Nepal. The
research team used this footage to analyze the hand movement patterns
and transitions during the vessel formation processes, comparing them
with those from the Indian communities.



==========================================================================
Out of the 31 identified patterns of hand movements; similarities could
be seen between different communities in approximately half of this
number (cross- cultural), ten were particular to the Nepalese community (cultural), and five were identified as unique to the particular
individual. The remaining movements were only observed once in one
individual.

Cross Recurrence Quantification Analysis (CRQA) is a method used to
quantify the dynamics of shared activity between two time series. CRQA was conducted on hand position sequences from different trials resulting in
plots showing the temporal relationship between all possible combinations
of hand positions in one trial with hand positions in another trial
during the fashioning. These analyses revealed that there were hand
position sequences that were unique to individual craftsmen.

The significance of this research This research revealed that there is
actually much variation in the formation process and the hand movements
of the individual craftsmen, even when producing traditionally-shaped
pottery in a manner that has been passed down for generations. From these results it can be surmised that each potter has been searching for their
own distinct way of forming the shape of the vessel within the constraints
of the tools used, such as the type of wheel, and differences in material.

Various theoretical models that have been proposed on the cultural
transmission of handicrafts have viewed the inheritance of such skills
as 'imitation' and 'transmitted information'. Conversely, this study
provides quantitative evidence that traditional 'inherited' craftsmanship
is more than mere imitation, shedding light on how individuals' ability
is flexibly adopted from exploratory activities channeled by the social environment (e. g. of the pottery workshop) and the processes behind
these factors. These aspects have been overlooked by existing theoretical models. The impact of these results will bring about the revision of
existing theories that have reduced the transmission of traditional
handicraft skills to 'imitation' and 'transmitted information'.

Furthermore, it is also hoped that this study's methodology and data
could be used to determine whether unattributed archaeological artefacts
were produced by an individual or several craftspeople.

Video: https://www.youtube.com/watch?v=UhsOVNn4wMg&feature=emb_logo Video: https://www.youtube.com/watch?v=e8CJhBNYRRw&feature=emb_logo

========================================================================== Story Source: Materials provided by Kobe_University. Note: Content may
be edited for style and length.


========================================================================== Journal Reference:
1. Enora Gandon, Tetsushi Nonaka, John A. Endler, Thelma Coyle,
Reinoud J.

Bootsma. Traditional craftspeople are not copycats: Potter
idiosyncrasies in vessel morphogenesis. PLOS ONE, 2020; 15 (9):
e0239362 DOI: 10.1371/ journal.pone.0239362 ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2020/10/201027105346.htm

--- up 9 weeks, 1 day, 6 hours, 50 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1337:3/111)