BIOTA - AN OBJECT-ORIENTED TOOL FOR MODELING COMPLEX ECOLOGICAL-SYSTEMS

Biota is an object-oriented software application for modeling, simulat ing, and learning about multispecies population dynamics. Biota uses a variety of mathematical models including versions of the Lotka-Volter ra models and the Nicholson-Bailey model, but goes far beyond the capa city of any one model. We begin by describing the class and object hie rarchies of Biota and its general functionality. Species, regions, and relations among species are all modeled as objects. This object-orien ted decomposition provides Biota with the capacity to model and simula te complex natural interactions among biological populations. Moreover , Biota allows a mixing of models and the representation of causal int eractions not found in standard population models. The mixing of model s, however, creates problems for estimating the parameters used in com plex simulations, detecting and correcting errors, and in understandin g the system being simulated. These difficulties are addressed using a novel approach to creating simulations, which we call the behavior pa rtitioning approach. We also discuss classroom experience with Biota, techniques for managing complexity, and its application to resource ma nagement.