Stamen reduction

Rudall, P. J., Abranson, K., Dransfield, J. and Baker, W. (2003). Floral anatomy in Dypsis (Arecaceae-Areceae) a case of complex synorganization and stamen reduction. Botanical Journal of the Linnean Society, 143,115-133. 

Dransfield et al., 1995) to more than one thousand (Dransfield et al., 2008a). The ancestral stamen number inferred for the palm family is six, which is also the ancestral number found for monocots as a whole (Nadot, unpubl. data). In four out of five subfamilies polyandry evolved several times from this trimerous androe-cium (with six stamens). The highest number of transitions towards polyandry, but also towards reduction in stamen number (from six to three) is found within subfamily Arecoideae, which include approx, half of all species of palms. It should be noted that flowers of all arecoid palms are unisexual and that almost all species are monoecious. 

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