Integration of developmental and environmental forcing in life history models of planktonic organisms

In a longer perspective the proposed research aims at integrating certain aspects of two major, although separated, domains in current biology: The first domain extends from the molecule to the organisms, while the second extends from organism to populati on biology, biodiversity studies, and ecology (Kafatos & Eisner 2004). Specifically I intend to develop life-history and individual growth models of planktonic organisms that include developmental as well as environmental forcing. A first version of this approach has been developed for the planktonic model organism Oikopleura dioica and is further developed at the Sars Centre and at the University of Bergen. The research with MD Ohman at SiO will primarily be concerned with the ecological basis including the environmental forcing of the model. Specifically the predation field of planktonic organisms will be focussed, but two other environmental variables: temperature and food are also to be addressed. Through the analysis of existing datasets we will inv estigate if food limitation affects the scaling relationship between metabolism on one hand and body size and temperature on the other as predicted from the current model. A submodel for the planktonic predation field, including visual and tactile predati on, is to be developed and included as a mortality risk parameter in the life-history model. Furthermore, the influence of water clarity (through its effect on the predation field) life history strategies in planktonic organisms will be investigated. Comp lementary to this, long time series of water clarity for four ocean areas: The California coast (CalCofi), the North Sea, the Baltic Sea and the Black Sea will be analyzed for possible food-web effects.