Predicting Population Dynamics from the Properties of Individuals: A Cross-Level Test of Dynamic Energy Budget Theory

Authored by Volker Grimm, Thomas G Preuss, Roger M Nisbet, Tjalling Jager, Benjamin T Martin

Date Published: 2013

DOI: 10.1086/669904

Sponsors: European Union United States Environmental Protection Agency (EPA) United States National Science Foundation (NSF)

Platforms: NetLogo

Model Documentation: ODD Flow charts

Model Code URLs: http://www.journals.uchicago.edu/doi/suppl/10.1086/669904/suppl_file/deb_daph_v1.nlogo

Abstract

Individual-based models (IBMs) are increasingly used to link the dynamics of individuals to higher levels of biological organization. Still, many IBMs are data hungry, species specific, and time-consuming to develop and analyze. Many of these issues would be resolved by using general theories of individual dynamics as the basis for IBMs. While such theories have frequently been examined at the individual level, few cross-level tests exist that also try to predict population dynamics. Here we performed a cross-level test of dynamic energy budget (DEB) theory by parameterizing an individual-based model using individual-level data of the water flea, Daphnia magna, and comparing the emerging population dynamics to independent data from population experiments. We found that DEB theory successfully predicted population growth rates and peak densities but failed to capture the decline phase. Further assumptions on food-dependent mortality of juveniles were needed to capture the population dynamics after the initial population peak. The resulting model then predicted, without further calibration, characteristic switches between small-and large-amplitude cycles, which have been observed for Daphnia. We conclude that cross-level tests help detect gaps in current individual-level theories and ultimately will lead to theory development and the establishment of a generic basis for individual-based models and ecology.
Tags
models growth allocation Daphnia-magna Life-history Reproduction Ecological theory Amplitude cycles Mytilus-edulis-l Deb theory