Evol Ecol Res 9: 987-1004 (2007) Full PDF if your library subscribes.
Evolutionarily stable dispersal with pattern formation in a mutualist–antagonist system
Curtis A. Smith* and William G. Wilson
University Program in Ecology and Department of Biology, Duke University, Durham, NC 27708, USA
Author to whom all correspondence should be addressed.
Question: How does the evolution of dispersal distance affect the persistence, distribution, and population dynamics of a mutualist–antagonist system capable of endogenous pattern formation?
Modelling approach: We let dispersal distance evolve within an individual-based model involving an obligate plant–pollinating seed parasite pair and a parasitoid that preys upon pollinator larvae. The model incorporates demographic parameters for ovule production, pollinator oviposition, pollinator and parasitoid visitation rates, in addition to background mortality probabilities for each of the three species. A corresponding non-spatial mathematical model verifies our representation of the interspecific dynamics.
Key assumptions: Individuals move over a homogeneous underlying environment with dispersal distances drawn from probability distribution kernels. Each species is subject to density-dependent reproduction. Pollinators and parasitoids make multiple visits per time step that are Poisson distributed.
Conclusions: Dependent on demographic parameter values, there is a spectrum of outcomes, including: (1) runaway selection for increased dispersal distance resulting in homogeneous distributions of all three species; (2) an evolutionarily stable state with pattern formation and metapopulation-like dynamics; and (3) rapid extinction of one or more species. Interestingly, a weak relaxation of the obligacy between the plants and the pollinators erodes the evolutionarily stable state with pattern formation. We argue that this dependence upon and sensitivity to obligacy may explain the lack of empirical observations of endogenous pattern formation in nature.
Keywords: disperse, evolutionarily stable state, heterogeneity, host–parasitoid, individual-based simulation, mathematical model, metapopulation dynamics, obligate mutualism, patches.
DOWNLOAD A FREE, FULL PDF COPY
IF you are connected using the IP of a subscribing institution (library, laboratory, etc.)
or through its VPN.
© 2007 Curtis A. Smith. All EER articles are copyrighted by their authors. All authors endorse, permit and license Evolutionary Ecology Ltd. to grant its subscribing institutions/libraries the copying privileges specified below without additional consideration or payment to them or to Evolutionary Ecology, Ltd. These endorsements, in writing, are on file in the office of Evolutionary Ecology, Ltd. Consult authors for permission to use any portion of their work in derivative works, compilations or to distribute their work in any commercial manner.
Subscribing institutions/libraries may grant individuals the privilege of making a single copy of an EER article for non-commercial educational or non-commercial research purposes. Subscribing institutions/libraries may also use articles for non-commercial educational purposes by making any number of copies for course packs or course reserve collections. Subscribing institutions/libraries may also loan single copies of articles to non-commercial libraries for educational purposes.
All copies of abstracts and articles must preserve their copyright notice without modification.