For four years, Gabriel Trujillo trekked the breadth of the United States and south into Mexico in search of a flowering shrub called the common buttonbush.
The plant is native to the varied climates of Canada, the U.S. and Mexico. Trujillo, a 31-year-old Ph.D. student at the University of California, Berkeley, wanted to know why it thrived in such a range of places, and whether the evolution of the species held possibilities for future habitat conservation and restoration efforts.
