Individual heterogeneity and stochastic population dynamics
Friday Seminar by Yngvild Vindenes
Demographic analysis infers population dynamics resulting from processes varying at the individual level (death, movement, reproduction, etc). Stochasticity and individual heterogeneity are two important challenges in such analyses. Even if all individuals in a population were identical, survival and reproduction are inherently probabilistic events (demographic stochasticity). Given that the outcomes of these events were the same for all individuals at one point in time, the underlying probabilities could still fluctuate over time (environmental stochasticity). In addition, individuals differ in factors like age, size and spatial location, as well as in other ways that are not readily identified (individual heterogeneity). Ignoring such heterogeneity can lead to biased parameter estimates and inaccurate predictions (e.g., regarding extinction risk). In addition it can potentially cause overall wrong conclusions.
In this talk I will present the main results from my doctoral work on individual heterogeneity and stochastic dynamics. Specifically, I will consider how individual heterogeneity can affect the extinction risk of a population, how it may affect rates of evolution, and how it can influence effects of climate change on population dynamics (in a population of eurasian oystercatchers).
Centre for Conservation Biology, Department of Biology, Norwegian University of Science and Technology, 7491 Trondheim, Norway