**AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** BUMBLE BEES ARE THE MOST ECONOMICALLY IMPORTANT NATIVE POLLINATORS IN THE UNITED STATES. THEY ARE GENERALIST POLLINATORS THAT VISIT A DIVERSE BREADTH OF BOTH CROP AND NON-CROP PLANTS TO COLLECT POLLEN AND NECTAR. THERE IS CURRENTLY A GAP IN WHAT MOLECULAR MECHANISMS DRIVE FLORAL RESOURCE VISITATION, AND HOW THIS VARIES BETWEEN UNIQUE BUMBLE BEE SPECIES. I WILL USE A COMBINATION OF COMPARATIVE AND FUNCTIONAL GENOMICS TO ASK WHETHER WE CAN LEVERAGE INSIGHTS FROM CHEMOSENSORY SYSTEMS TO IMPROVE BUMBLE BEE POLLINATION SERVICES. TO ADDRESS THIS, I WILL COMPLETE THE FOLLOWING OBJECTIVES: OBJECTIVE 1A. IDENTIFY ALL CHEMOSENSORY GENES IN FIVE AGRICULTURALLY IMPORTANT BUMBLE BEE SPECIES, B. IMPATIENS, B. VOSENSENSKII, B. HUNTII, B. EPHIPPIATUS AND B. TERRESTRIS, TO EXAMINE PHYLOGENETIC RELATIONSHIPS BETWEEN SPECIES; OBJECTIVE 1B. COMPARE VARIATION IN CHEMOSENSORY GENES BETWEEN SPECIES AND PERFORM EVOLUTIONARY ANALYSES; AND OBJECTIVE 2. FUNCTIONALLY CHARACTERIZE CANDIDATE CHEMOSENSORY GENES WITH EVIDENCE OF ADAPTIVE VARIATION BETWEEN SPECIES. RESULTS FROM THIS STUDY CAN BE LEVERAGED TO PREDICT FLORAL RESOURCE VISITATION AND MANIPULATE SENSORY CAPACITY OF BUMBLE BEES TO INCREASE VISITATION TO CROP PLANTS. THIS PROPOSAL ALIGNS WITH THE POLLINATOR HEALTH: RESEARCH AND APPLICATION PRIORITY AREA OF THE PLANT HEALTH AND PRODUCTION AND PLANT PRODUCTS PROGRAM AREA. THIS POSTDOCTORAL RESEARCH PROJECT WILL BE COMPLETED BY KALEIGH FISHER (PD - UC DAVIS) UNDER THE PRIMARY MENTORSHIP OF DR. SANTIAGO RAMIREZ (UC DAVIS). THE PROJECT ALIGNS WITH THE AFRI EDUCATION AND WORKFORCE DEVELOPMENT PROGRAM GOALS BY PREPARING ME VIA CAREER TRAINING, MENTORSHIP AND SCIENTIFIC TRAINING.