CAREER: UNRAVELING THE EVOLUTIONARY HISTORY OF TOOTHED WHALE ACOUSTIC COMMUNICATION -TOOTHED WHALES (DOLPHINS, PORPOISES, AND RELATIVES) ARE NOT ONLY AMONG THE MOST ACOUSTICALLY SPECIALIZED GROUPS OF VERTEBRATES, BUT THEIR COMMUNICATION IS POTENTIALLY ONE OF THE MOST COMPLEX IN THE ANIMAL KINGDOM. THIS IS BECAUSE TOOTHED WHALES ARE OPEN-ENDED VOCAL LEARNERS, MEANING THEY LEARN NEW VOCALIZATIONS THROUGHOUT THEIR LIFETIME. ADDITIONALLY, THEIR UNIQUE SOUND GENERATOR ALLOWS THEM TO PRODUCE A RICH REPERTOIRE OF ACOUSTIC SIGNALS. ALTHOUGH TOOTHED WHALE ACOUSTIC SIGNALS HAVE BEEN STUDIED EXTENSIVELY FOR OVER 70 YEARS, THE SCOPE OF THEIR VOCAL REPERTOIRE AND THE UNDERLYING FACTORS SHAPING THEIR REPERTOIRE EVOLUTION REMAINS LARGELY UNKNOWN. THIS REPRESENTS AN IMPORTANT GAP IN KNOWLEDGE THAT LIMITS OUR ABILITY TO DISCOVER THE MECHANISMS UNDERLYING THE EVOLUTION OF ANIMAL ACOUSTIC COMMUNICATION. FURTHERMORE, THE QUESTION OF HOW DIVERSE TOOTHED WHALE VOCAL REPERTOIRES ARE IS RELEVANT TO THE STUDY OF ANIMAL ECOLOGY AND BEHAVIOR, OCEAN HEALTH, AND THE GLOBAL ECONOMY. TOOTHED WHALES ARE APEX PREDATORS AND ECOSYSTEM ENGINEERS THAT CONTRIBUTE TO THE MAINTENANCE OF A HEALTHY OCEAN AND LOCAL ECONOMIES. BECAUSE THEY RELY ALMOST ENTIRELY ON SOUND FOR THEIR SURVIVAL, THEY ARE VULNERABLE TO HUMAN ACTIVITIES THAT GENERATE UNDERWATER NOISE. BY QUANTIFYING THE MAKEUP OF THEIR VOCAL REPERTOIRE AND UNDERSTANDING THEIR EVOLUTIONARY AND ECOLOGICAL DRIVERS, THIS STUDY CAN IMPROVE OUR ABILITY TO MONITOR THEIR POPULATIONS AND PREDICT THE IMPACTS OF AN INCREASINGLY WARMER AND NOISIER OCEAN, PARTICULARLY IN AREAS WHERE THEY SERVE AN ECONOMIC ROLE. THE STUDY INTEGRATES ARTIFICIAL INTELLIGENCE AND MACHINE LEARNING APPROACHES TO QUANTIFY TOOTHED WHALES? VOCAL REPERTOIRES WITH PHYLOGENETIC TOOLS AND FIELD STUDIES, TO TEST HYPOTHESES ABOUT THE ROLE OF SOCIAL AND ENVIRONMENTAL FACTORS IN REPERTOIRE DIVERSITY AND COMPOSITION. ACROSS THE FIVE-YEAR PERIOD OF THE AWARD, THE PI WILL TRAIN 105 UNDERGRADUATES IN BIOACOUSTICS, ANIMAL BEHAVIOR, AND SOUNDSCAPE ECOLOGY THROUGH A SEMESTER COURSE-BASED UNDERGRADUATE RESEARCH EXPERIENCES (CURE), TEN UNDERGRADUATE STUDENTS THROUGH A 3-WEEK PAID FIELD RESEARCH EXPERIENCE, TWO PH.D. STUDENTS, ONE TECHNICIAN, AND ONE POSTDOC. THE PI?S GOAL IS TO RECRUIT A DIVERSE STUDENT COHORT TO WORK IN A DEEPLY COLLABORATIVE FORMAT TO HELP STUDENTS DEVELOP FEELINGS OF CONFIDENCE, BELONGING, EQUITY, AND COMMUNITY. BY INTENTIONALLY CREATING A SYNERGISTIC ENVIRONMENT FOR EXCHANGE OF IDEAS AND RESEARCH OPPORTUNITIES, THE PROGRAM WILL FOSTER INNOVATION AND CREATIVITY, EMPOWERING STUDENTS TO SELECT CAREERS IN STEM AND BROADER JOB MARKET OPPORTUNITIES WITHIN AND OUTSIDE ACADEMIA. THE CONTRIBUTION OF THIS RESEARCH PROGRAM IS SIGNIFICANT BECAUSE IT WILL GENERATE NOVEL COMPUTATIONAL APPROACHES WITH TRANSFERABLE APPLICATIONS TO THE STUDY OF ANIMAL COMMUNICATION. THIS GRANT WAS CO-FUNDED BY THE SYSTEMATICS & BIODIVERSITY SCIENCE CLUSTER, DIVISION OF ENVIRONMENTAL BIOLOGY, AND THE BEHAVIORAL SYSTEMS CLUSTER, DIVISION OF INTEGRATIVE ORGANISMAL SYSTEMS, DIRECTORATE OF BIOLOGICAL SCIENCES. THIS AWARD REFLECTS NSF'S STATUTORY MISSION AND HAS BEEN DEEMED WORTHY OF SUPPORT THROUGH EVALUATION USING THE FOUNDATION'S INTELLECTUAL MERIT AND BROADER IMPACTS REVIEW CRITERIA.- SUBAWARDS ARE NOT PLANNED FOR THIS AWARD.