Annual Plant Reviews (2009) 38, 238–295 www.interscience.wiley.com
doi: 10.1002/9781444314557.ch7
Chapter 7
SEED DISPERSAL AND CROP
DOMESTICATION:
SHATTERING, GERMINATION
AND SEASONALITY IN
EVOLUTION UNDER
CULTIVATION
Dorian Q. Fuller
1
and Robin Allaby
2
1
Institute of Archaeology, University College London, London, UK
2
Warwick, HRI, University of Warwick, Wellesbourne, Warwick, UK
‘The Angiosperm seed had a double significance. It not only gave command of dry
land to plant life, but it provided the means by which mankind has been able to
obtain an ample and assured food supply. To the Angiosperm seed, perhaps more
than to any other structure, the economic evolution of the human race is due.’
Oakes Ames (1939, p. 5)
Abstract: The transition between wild plant forms and domesticated species can
be considered an evolutionary adaptation by plants in response to a human driven
ecology. Evidence from archaeobotany and genetics is providing deeper insight
into this evolutionary process in terms of its scale, mechanism and parallelism
between species. The evidence indicates that the timescale of this evolution was
considerably longer than previously supposed, raising questions about the mode
of human mediated selection pressure and increasing the importance of the role of
pre-domestication cultivation. Different selection pressures were chronologically
separated into at least three stages, each important at different points of the evolu-
tionary process affecting different traits. Early selection pressures were ultimately
driven by the pre-domestication sowing activities affecting the polygenically con-
trolled germination and seed size traits. Later, in the second stage, release of natu-
ral selection pressures of dispersal requirements led to modification of architecture
such as awns loss of awns and increase in dispersal unit size. The loss of disper-
sal requirement combined with positive pressure through harvesting practice led
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Fruit Development and Seed Dispersal Edited by Lars Østergaard
© 2010 Blackwell Publishing Ltd. ISBN: 978-1-405-18946-0