Document Type
Article - postprint
Department
Physics (HMC)
Publication Date
11-2011
Abstract
The role of petal spurs and specialized pollinator interactions has been studied since Darwin. Aquilegia petal spurs exhibit striking size and shape diversity, correlated with specialized pollinators ranging from bees to hawkmoths in a textbook example of adaptive radiation. Despite the evolutionary significance of spur length, remarkably little is known about Aquilegia spur morphogenesis and its evolution. Using experimental measurements, both at tissue and cellular levels, combined with numerical modelling, we have investigated the relative roles of cell divisions and cell shape in determining the morphology of the Aquilegia petal spur. Contrary to decades-old hypotheses implicating a discrete meristematic zone as the driver of spur growth, we find that Aquilegia petal spurs develop via anisotropic cell expansion. Furthermore, changes in cell anisotropy account for 99 per cent of the spur-length variation in the genus, suggesting that the true evolutionary innovation underlying the rapid radiation of Aquilegia was the mechanism of tuning cell shape.
Rights Information
© 2011 The Royal Society
Terms of Use & License Information
DOI
10.1098/rspb.2011.1873
Recommended Citation
J. R. Puzey, S. J. Gerbode, S. A. Hodges , L. Mahadevan and E. M. Kramer, “Evolution of spur length diversity in Aquilegia petals is achieved solely through cell shape anisotropy” Proc. R. Soc. B 279:1733, 1640 (2012). doi: 10.1098/rspb.2011.1873
Comments
The author's post-print manuscript is available here for download. The published PDF is available from Royal Society Publishing at http://dx.doi.org/10.1098/rspb.2011.1873.