Meeting Abstract

S11-2   08:00 - 08:30  Introduction to the symposium “HaloDaSH: The deep and shallow history of aquatic life's passages between marine and freshwater habitats” Schultz, ET*; Park Boush, L; Schultz, Eri; University of Connecticut; University of Connecticut eric.schultz@uconn.edu https://halodash.research.uconn.edu/

This symposium highlights research into how biological exchanges between salty and freshwater habitats have transformed the biosphere. Life in the ocean and in freshwaters have long been intertwined; multiple major branches of the tree of life originated in the oceans and then adapted to and diversified in freshwaters. Similar exchanges continue to this day, including some species that continually migrate between marine and fresh waters. Questions that arise include: When did major colonizations of fresh waters happen? What circumstances facilitated the transition? How frequent have been returns to marine habitats? How porous is the boundary: is change in halohabitat routine, requiring few modifications, or does it rarely occur because it requires special conditions and substantial genomic alterations? What adaptive changes occurred to accommodate the physiochemical and ecological differences? How do marine and freshwater lineages differ in organism-level features, ecological relationships, evolutionary processes? To what extent has diversification been propelled by the transitions? What differences in ecosystem services arise from these transformations? In what ways are the freshwater and marine forms subject to different anthropogenic stressors? The purpose of the symposium is to integrate findings at multiple levels of biological organization and from disparate fields, across biological and geoscience disciplines. The transdisciplinary endeavor will enable us to better understand responses to global change in each realm, and will impact curricula for undergraduates and graduate students.