Christopher T. DiVittorio
PhD in Integrative Biology, UC Berkeley

UC MEXUS residency from November 2015 to present
Christopher T. DiVittorio

I am an evolutionary ecologist studying the adaptive radiation of Encelia sunflowers in México and the southwest United States. At the University of California, Riverside, I am taking advantage of the desert climate and proximity to many different populations of Encelia to establish a large-scale and long-term common garden at the historic Citrus Experimental Station located south of the UCR campus. In addition, my academic advisor—UC MEXUS Director Dr. Exequiel Ezcurra—has extensive experience studying the plants of northwest México and is actively involved in a number of conservation efforts in the region.

The goals of this study are to build on previous research, identifying patterns of trait evolution and physiological adaptation between different species adapted to a variety of different niches. By growing all species in the same place we can control for environmental influences and study the genetic basis of differentiation in parental taxa and hybrids. In addition, several species of conservation concern are being propagated to buffer against potential extinction as well as to investigate whether hybridization from neighboring common species is a threat to the persistence of this taxon. For example, Encelia densifolia exists in the middle of the remote Sierra de Santa Clara, an extinct cluster of volcanoes in the Vizcaíno Peninsula of Baja California Sur that serve as "sky islands," preserving disjunct populations of species such as boojum and jojoba whose next nearest populations are hundreds of kilometers away. The entire known species of Encelia densifolia exists in this volcano, and is currently numbered at only 67 individual plants.

My research has involved over fifteen undergraduates from UCR and UCB, seven high school students from communities in México near my study sites, and forged long-term collaborations with researchers from the Universidad Nacional Autónoma de México, Universidad Autónoma de Baja California, Yale University, University of Michigan, and UC Berkeley. Additionally, I have also worked for over 8 years closely with officials from the federal Vizcaíno Biosphere Reserve in Baja California Sur, where most of my research takes place. I also organized an international botanical expedition to the Sierra de Santa Clara in Baja California Sur, was a founding member of the Next Generation Sonoran Desert Researchers, and was elected as Vice-Chair of Ecological Society of America Natural History Section for 2014-1016. In addition to México I have performed research in Alaska, the Amazon Basin, French Polynesia, and Panama.