Andrea’s research interests are in the theory of differential equations and their applications in mathematical biology. Most recently, she has worked with David Brown in the Math Department and Miro Kummel in the Environmental Program on modeling an insect predator-prey system. Their field system consists of ladybugs and aphids, which are patchily distributed on racemes of yucca plants in the Rocky Mountains of Colorado. The patches are connected by the relatively fast dispersal of the ladybugs, whereas the aphids are relatively sessile. In a 30-day field study they observed a split of the aphid population sizes into extremely large and extremely small populations, a phenomenon known as spatial self-organization or pattern formation. In order to study the effects of density independent predator and prey immigration into the system and migration due to the predator’s attraction to predation, work in progress includes the study of a two-patch, ordinary differential equations model, which is continuous in time and discrete in space (with David Brown, Miro Kummel, and Hannah Thompson).