Functional significance of regular archaeocyathan central cavity diameter; a biomechanical and paleoecological test

摘要: Theoretical and experimental biomechanical approaches are used to test the effect regular archaeocyathan central cavity diameter has on generation of passive flow through skeleton. These results then predict a correspondence between gross morphology paleoen- vironmental occurrence. Previous work demonstrated that generates flow, via Bernoulli viscous entrainment effects, its porous walls for suspension feeding, phenomenon occurs in modern sponges. Efficacy depends upon area excurrent pore (i.e., cavity) over which ambient is moving. Consequently, archaeocyaths should have maximized their diameters. Five-centimeter-long, conical cylindrical acrylic pipes with varying end diameters were tested flume document relative effects entrainment. Each pipe was oriented perpendicular direction uniform field, fluorescein dye injected at pipe's mid-length visualization. Models different-sized apertures consistently exhibit movement larger opening greater speeds than models identically sized apertures, thereby suggesting significant operating concert effects. To similar archaeocyaths, four brass constructed Both volume flux speed exiting water increased as increased. An analysis morphologies occur nature confirm these results. Regular most commonly close outer wall diameter, maximizing area. implications paleoecology. Environments low-mag- nitude currents support individuals higher energy settings. Data occurrence morphotypes within bioherms energies from South Australia this prediction.