WE ALL WONDER AT THE COLORS AND SHAPES OF OUR FAVORITE FRUITS, VEGETABLES, AND GRAINS--THE COLORS AND SIZES OF DIVERSE MAIZE EARS, THE SHAPE AND SPICINESS OF AN ARRAY OF CHILE PEPPERS. THIS DIVERSITY ASTOUNDS. WHILE CROP DIVERSITY HAS LONG BEEN OF IMMEDIATE INTEREST TO HUMANKIND, THE PAST CENTURY HAS SEEN SCIENTIFIC SCRUTINY OF THE PHENOTYPIC AND GENETIC DIVERSITY OF LANDRACES (OR TRADITIONAL VARIETIES) OF CULTIVATED SPECIES AND THEIR WILD RELATIVES. RESEARCH HAS ILLUMINATED FACTORS SHAPING CROP DIVERSITY--LARGELY MOTIVATED BY THE VALUE OF CROP DIVERSITY FOR BREEDING. RAPID CLIMATE CHANGE HAS ENHANCED INTEREST IN THE TRAITS AND ALLELES THAT COULD INCREASE CROP PRODUCTIVITY UNDER ADVERSE CONDITIONS, SUCH AS RISING TEMPERATURES AND VARIABLE PRECIPITATION. CROPS GROWN IN THEIR CENTERS OF DIVERSITY OR ORIGIN TEND TO BE DIVERSE LANDRACES AND THEY ARE PLANTED ACROSS ENVIRONMENTAL GRADIENTS. THIS COMBINATION OF DIVERSITY OF GENETIC AND ENVIRONMENTAL VARIATION IS ESPECIALLY SUITED TO THE TASKOF LINKING PHENOTYPES THAT IMPROVE PRODUCTIVITY UNDER CLIMATE STRESS (I.E., ADAPTATIONS) TO THE GENETIC VARIANTS UNDERLYING THOSE PHENOTYPES. WE WILL RELATE PHENOTYPIC, MOLECULAR, AND CLIMATIC VARIATION TO UNDERSTAND HOW PATTERNS OF GENETIC VARIATION HAVE BEEN SHAPED BY THE ENVIRONMENT AND HIGHLIGHT REGIONS OF THE GENOME CONTROLLING ENVIRONMENTAL ADAPTATION TO FACILITATE OUR UNDERSTANDING OF MECHANISMS OF ABIOTIC STRESS ADAPTATION. IN PARTICULAR, USING WILD AND LANDRACE COLLECTIONS OF CHILE PEPPER , WE WILL: (I) LOOK AT THEIR GENETICS AND DISCERN THE GENETIC RELATIONSHIPS BETWEEN DIVERSE CHILE PEPPER COLLECTIONS FROM THEIR CENTER OF ORIGIN AND DIVERSITY; (II) USE THE GENETIC AND ENVIRONMENTAL INFORMATION ABOUT OUR COLLECTIONS TO FURTHER IDENTIFY POINTS ALONG THE GENOME INVOLVED IN ENVIRONMENTAL ADAPTATION (ESPECIALLY TO DROUGHT); AND (III) IN THE GREENHOUSE, LOCATE QUANTITATIVE TRAIT LOCI (QTL), OR SPECIFIC REGIONS OF THE GENOME, THAT AFFECT PLANT GROWN AND PERFORMANCE UNDER DROUGHT USING IN MEXICAN AND US MATERIALS. THUS, WE WILL USE MULTIPLE LINES OF EVIDENCE TO ASSEMBLE A WELL-SUPPORTED LIST OF POINTS ALONG THE GENOME ASSOCIATED WITH EXTREME ABIOTIC CONDITIONS AND PLANT PERFORMANCE IN THE FACE OF DROUGHT STRESS, WHILE ALSO BETTER UNDERSTANDING THE WAYS GENETIC DIVERSITY VARIES ACROSS DIVERSE LANDSCAPES.