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Petraitis - Detection of alternative stable states in extant communities: the need for a historical perspective

Detection of alternative stable states in extant communities: the need for a historical perspective
Peter S. Petraitis
Department of Biology, University of Pennsylvania, Philadelphia, PA 19104-6017, USA, ppetrait@sas.upenn.edu
The possibility that different assemblages of species may exist as alternative stable states remains largely unexplored by experimental ecologists because of a variety of conceptual and experimental problems. In particular, ecologists often ignore the distinction between the processes that initiate the switch among alternative states and the positive-feedback processes that maintain those states. This is analogous to the problem of assessing the causes for the origin versus maintenance of traits in the fossil record. Appropriate experimental designs for detecting alternative states in extant systems are discussed. It is clear that good experimental designs must account for successional (i.e., historical) changes in community structure. Suggestions for improving experimental tests are proposed and unresolved issues are highlighted.


next up previous
Next: Roopnarine et al. - Up: Special Symposium - From Previous: Padilla - Phenotypic Plasticity
Peter Roopnarine 2005-04-12