Hypoxic events can strongly reduce productivity and nutrient recycling in ecosystems and increase probability of species extinctions. Preservation potential of hypoxic events in the fossil record can be low if there is a relatively long time for ecosystem recovery in the wake of oxygen depletion, if depth of bioturbation is large, and/or if sedimentation rate is very slow. In this project, we will use actualistic and paleoecological methods to determine conditions under which benthic responses to hypoxic events can be preserved in the fossil record. First, we will assess preservation potential of benthic respones to hypoxia in Holocene sediments on continental shelves off southern California and in the Adriatic Sea. Second, we will evaluate temporal and spatial variability in the composition of benthic communities in successions characterized by alternations of normoxic and hypoxic conditions in semi-enclosed basins during the Triassic and Early Jurassic (Alps) and Miocene (Vienna and Korneuburg basins).