Biological diversity is fundamental to ecosystem functions and services. Adaptive diversity evolves because of organismal trade-offs, which originate in the structure of genetic and physiological pathways and play out in ecological interactions. Dr. Friesen will present work in Medicago truncatula that integrates field, greenhouse, and genomic approaches to understand local adaptation to saline soils in Tunisia, including the potential for interactions with symbiotic Sinorhizobium bacteria to influence salt tolerance.