He obtained his Doctor of Philosophy from the Department of Ecology and Evolutionary Biology at the University of Arizona in 1991 with a dissertation entitled "Optimal use of ethnobotanical resources by the Mountain Pima of Chihuahua, Mexico".
Among other institutions, he has held professional positions at Washington State University, Biosphere 2, and the Universidad Autónoma del Estado de Morelos (in Cuernavaca, Mexico). He is the author or co-author of the botanical names of some 120 taxa, including Berberis pimana, Hymenocallis clivorum, Hymenocallis pimana, Laennecia pimana, Pectis pimana, Prionosciadium saraviki, and Yucca declinata.
