Document: CAT-3-51-8

Patterns of individual variation and its implications for population models.

PFISTER, C.A.*

University of Chicago, Chicago, IL ¹

Abstract:
Comparisons of population models indicate that model choice is dependent upon the type of variability among individuals. Variation among individuals that is positively correlated through time, termed inertia, can greatly affect the outcome of population models. I have quantified the nature of variability in a variety of organisms in order to determine how common inertia terms are in natural populations. I review methodology for distinguishing inertia from size-based processes. Using demographic data for plants, invertebrates, and fishes, I found significant growth inertia only in plants and some invertebrates. Other invertebrates, including a limpet and seastar species, and intertidal fishes showed no significant growth inertia terms. These results suggest that although there are species for which some analytical models may be poor descriptors of future population structure, they may readily be identified from demographic data.

Keywords: population models, variability, inertia, matrix models, individual based models, marine invertebrates

This abstract is being presented at: 2:45 PM in session:
Oral Session #46: Modeling Populations and Statistical Ecology.