Publications
“Sonoran Desert columnar cacti and the evolution of generalized pollination systems”, Ecological Monographs, vol. 71, no. 4, pp. 511-530, 2001.
, “Historical vicariance and postglacial colonization effects on the evolution of genetic structure in Lophocereus, a Sonoran Desert columnar cactus”, Evolution, vol. 56, no. 11, pp. 2214-2226, 2002.
, “Genetic diversity in columnar cacti”, Columnar cacti and their mutualists: Evolution, Ecology, and Conservation. University of Arizona Press, Tucson, AZ, pp. 122-133, 2002.
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