Das Projekt "Individualitaet in der Biologie - unterschiedliche Konzepte und ein neuer Ansatz aus der Sicht der Prozessontologie" wird vom Umweltbundesamt gefördert und von Universität Zürich, Institut für Umweltwissenschaften durchgeführt. In this century different biologists have tried to put forward dynamic concepts of evolution in the light of new empirical and theoretical discoveries. However, these concepts are still embedded in the Aristotelian-Cartesian ontology based on the static nature of substances and matter. This project plans to first present four major concepts in the life sciences and critically work out their ontological background: 1. The Evolutionary Synthesis combines the Darwinian theory of evolution with the results of modern genetics. 2. The Open Systems Theory holds that every organism represents an open system interacting with its environment. 3. The Hierarchy Theory postulates that biological phenomena, especially those connected with emergence (the appearance of new and unpredictable qualities), in the end can be interpreted as reflections of the hierarchical organization of nature. 4. The Symbiotic Theory assumes that the eucaryontes developed from several procaryontes living in a symbiotic relationship. Symbio(gene)sis is therefore an important source of evolutionary novelty. It will be shown how functional units from the gene to the ecosystem are defined in the above-mentioned concepts and why they are treated as 'individual' entities. The respective ontological prerequisites will be analyzed and compared. It is the starting position of this project, that with the traditional ontological foundations it is not possible to properly appreciate the dynamic nature of these concepts. It is not enough merely to enlarge the scope of traditional ontology to fit entities like 'gene', 'cell', 'organism', 'population', 'ecosystem', 'species' etc. as functional units into dynamic concepts, because this leads to controversies between reductionism and holism that on principle cannot be solved. A new approach shall then be introduced which is based on the process ontology of A.N. Whitehead. Other than the substantialistic mode of thinking in traditional ontology, process ontology postulates a relational constitution of the individual entities. The properties of an individual constitute themselves in interaction with its environment. This leads to a dynamic concept of duration: traditionally, an individual remains itself, in spite of change. In process ontology, an individual is seen as a succession of interactions, which make it what it is through change. On this foundation, a new understanding of individual entities, neither reductionistic nor holistic, shall be developed. This understanding will also have consequences for applications of new results of the life sciences in ethics, anthropology, and medicine. The project will produce results on different levels: a structural comparison of functional units as defined by different biological disciplines, a clarification of the respective ontological background, an alternative ontology as a common foundation for the different biological disciplines, an outline of the practical consequences.