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Age structure

We have now ahd an introduction to some of the general ideas that come up when dealing with nonlinear models, and will trun to the more specialized case of age structure.  We think that age structure plus density dependence should elad to cycles, and the goal will be to see if we can distinguish among different kinds of biological causes for the cycles.  We'll approach this in two ways -- by looking at a way to get a relatively simple model for age dependent interactions using differential delay equations.  We'll then look at the question from a much more general viewpoint (the Higgins et al. approach).  If time permits, we'll finish by looking at Tribolium dynamfrom several points of view.



* means required reading

  *The Systematic Formulation of Tractable Single-Species Population Models Incorporating Age Structure.  W. S. C. Gurney, R. M. Nisbet, J. H. Lawton.   Journal of Animal Ecology, Vol. 52, No. 2. (Jun., 1983), pp. 479-495.

*Density Dependence and Age Structure: Nonlinear Dynamics and Population Behavior.  Kevin Higgins, Alan Hastings, Louis W. Botsford.  American Naturalist, Vol. 149, No. 2. (Feb., 1997), pp. 247-269.

Discrete and Continuous Insect Populations in Tropical Environments
                    H. C. J. Godfray, M. P. Hassell
                    Journal of Animal Ecology, Vol. 58, No. 1. (Feb., 1989), pp. 153-174.

Nonlinear Demographic Dynamics: Mathematical Models, Statistical Methods, and Biological Experiments
                    Brian Dennis, Robert A. Desharnais, J. M. Cushing, R. F. Costantino
                    Ecological Monographs, Vol. 65, No. 3. (Aug., 1995), pp. 261-282.