Niche partitioning, larval recruitment, behavioral patterns and taphonomy of Recent Isocrinidae (Crinoidea): paleo- ecological implications

Four aspects of the biology of Recent stalked crinoids in the Straits of Florida are examined as they contribute to understanding paleoecological processes: 1) niche partitioning of habitat and food among four species distributed as three sympatric pairs--does it support or refute tiering, hydrodynamic and food partitioning hypotheses proposed for fossil taxa. Measured variables include current velocity, stalk height, crown diameter, filter density, gut contents and available food; 2) larval recruitment contributions to aggregated versus scattered populations; contributions of recruitment and relocation of vagile adults in re-establishing aggregations following physical disturbance; 3) relationship between possible behavioral patterns (feeding, activity or locomotory patterns or cycles) and variations in current regime and 4) skeletal contributions of Recent crinoids to sediment as an analogue for depositional processes in ancient crinoidal sediments--analyses of post-mortem processes and potential preservational biases. Work will be conducted via submersible, time-lapse cinematography, morphological, photographic and sedimentological analyses of collected material. Isocrininds represent major components of macroepibenthic assemblages in the study area and have a fossil record dating to the Triassic. As such, they represent an excellent analogue for paleoecological processes.