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The CECD is an AHRC funded research group dedicated to examining the evolutionary underpinnings of human cultural behaviour, past and present. more>

Page Title - projects
Phase 1: Cultural innovation and transmission: Project 043
Investigating evolutionary adaptive radiation patterns in the history of bicycles

SUPERVISOR: - Prof Stephen Shennan and Dr. Mark Lake

Jay Venti ()
Mark Lake (Institute of Archaeology, University College London)

It has long been proposed that cultural change looks like biological change, in that they both can be modelled as evolutionary processes that 'explore' design space. This project investigates a particular macroevolutionary phenomenon characterized as an adaptive radiation in palaeontology, in which, using Kauffman's 1995 language, evolutionary processes explore biological design space by mapping out the basic types first and 'fill in' detailed variation later. The classic biological example of an adaptive radiation is the Cambrian explosion, where phyla appeared early in the explosion and the 'filling in' constituted the emergence of the lower taxonomic orders. This project will investigate whether the same phenomenon occurs in technological design space. It will examine the technological development of the bicycle by developing a system to encode technological features; this encoding will pay attention to functional dependencies, and use these dependencies to classify sets of design classes analogous to high orders such as phyla in the biological case. Using this encoding scheme, the project will then build a taxa data set recording time of the appearance, and extinction of each design taxa. Then clade diversity statistics, borrowed from palaeontology, will be applied. Clade diversity statistics indicate to what degree a clade is bottom heavy, that is to what degree there is an excess of early developing sub-clade representatives within the given clade under investigation. In our case, we will be looking at the overall clade of bicycles and examine if there has been an excess of taxa exploring broad sub classes of bicycle technology that occurred during early development of the bicycle. A strong bottom heavy signal would indicate that there has been an adaptive radiation at the beginning of the bicycle technological sequence.

Secondary goals: another issue of interest is the degree to which, technological borrowing has occurred versus purely cladistic or horizontal evolutionary transmission. To investigate this, morphological split tree decompositions methods will be used to investigate the degree of reticulation.

Lake, M.W. and J. Venti (2009).
Quantitative analysis of macroevolutionary patterning in technological evolution: bicycle design from 1800 to 2000. In: S. J. Shennan (ed.) (ed\s) Pattern and Process in Cultural Evolution. University of California Press. 147-162.