SFI Working Paper Abstract

Title:Nonlinear Oscillations in Polyps of the Colonial Hydroid Podocoryne Carnea
Author(s):Andreas Wagner, Steven R. Dudgeon, Rimas J. Vaisnys, and Leo W. Buss
Paper #:97-07-066
Abstract:Cnidarian colonies, while simple metazoans lacking true organs, all share one colony-wide system of physiological integration, the gastrovascular system. The circulation of gastrovascular fluid is responsible for the distribution of metabolites within a colony (Crowell, 1957; Strehler and Crowell, 1961; Rees et al., 1970). Recent experimental findings have shown that the physiological state of the gastrovascular system is a key determinant of colony morphology and life history. For example, Blackstone and Buss (1992, 1993) altered gastrovascular physiology in the hydroids “Hydractinia symbiolongicarpus” and “Podocoryne carnea” using an uncoupler of oxidative phosphorylation, and documented pronounced changes in colony morphology and age-of-first reproduction. Dudgeon and Buss (1995) performed an analogous experiment. They altered gastrovascular circulation in “H. symbiolongicarpus” by microsurgery, while holding gastrovascular physiology constant, and succeeded in eliciting the stable transformation of one colony growth phenotype into another and vice versa. Yet, despite its apparent importance to colony morphogenesis, studies of gastrovascular circulation have been largely restricted to description and analysis of flow in localized regions of growth (Berrill, 1949; Hale, 1960; Wyttenbach, 1973; Schierwater et al., 1992; Buss and Vaisnys, 1993; Blackstone, 1996; Van Winkle and Blackstone, in press).
Keywords:nonlinear oscillators, hydrozoa, podocoryne carnea, vascular systems, hydroids, invertebrates, development