Albion College

Mathematics and Computer Science

Mathematics and Computer Science

COLLOQUIUM

Chaotic Dynamics and Lattice Effects Documented in Experimental Insect Populations

Shandelle M. Henson

Guided by the predictions of a discrete-time mathematical model, we induced a sequence of bifurcations (dynamic changes) in laboratory insect populations by manipulating one of the biological parameters in the system. In particular, we were able to induce chaotic dynamics. The data from these 8-year-long time series show the fine structure of the deterministic chaotic attractor as well as lattice effects (dynamic effects arising from the fact that organisms come in discrete units). We show that "chaos" is manifest in discrete-state noisy biological systems as a tapestry of patterns that come from the deterministic chaotic attractor and the lattice attractors, all woven together by stochasticity.

References

References

- Henson, S. M., Costantino, R. F., Cushing, J. M., Desharnais, R. F., Dennis, B., and A. A. King 2001. Lattice effects observed in chaotic dynamics of experimental populations. Science 294:602-605.

http://www.andrews.edu/~henson/HensonEtAlScience2001.pdf - Dennis, B., Desharnais, R. A., Cushing, J. M., Henson, S. M., and R. F. Costantino 2001. Estimating Chaos and Complex Dynamics in an Insect Population. Ecological Monographs 71:277-303.

http://www.andrews.edu/~henson/EcoMongr01.pdf - Henson, S. M., King, A. A., Costantino, R. F., Cushing, J. M., Dennis, B., and R. A. Desharnais 2003. Explaining and predicting patterns in stochastic population systems. Proceedings of the Royal Society of London B 270:1549-1553.

http://www.andrews.edu/~henson/MeanModeReprint.pdf - King, A. A., Costantino, R. F., Cushing, J. M., Henson, S. M., Desharnais, R. A., and B. Dennis 2004. Anatomy of a chaotic attractor: Subtle model-predicted patterns revealed in population data. Proceedings of the National Academy of Sciences 101:408-413.

http://www.andrews.edu/~henson/PNAS2004.pdf