Ecological and evolutionary dynamics of age-structured populations in fluctuating environments
Friday seminar by Bernt-Erik Sæther
One striking biological phenomenon is the large interspecific variation in the period of time needed for a female to produce a new female that can replace herself in the next generation. These differences in generation time have huge influences on dynamics of populations as well as for evolutionary processes in a changing environment. In this talk, I will show based on data from long-term demographic studies of birds and mammals that variation in population growth rates can be surprisingly well explained by basic species-specific life history characteristics. These results are obtained by using fluctuations in the total reproductive value of the population that enables us to account for random fluctuations in age-distribution. The pattern of variation in age-specific contributions to the total reproductive value and to stochastic components of population dynamics was correlated with the position of the species along the slow-fast continuum of life history variation. In the last part of the talk, I will show how this approach describing the dynamics by the total reproductive can also be used to analyse evolutionary processes. I illustrate this by estimating effective population size and fluctuating selection on quantitative characters in age-structured populations.
Bernt-Erik Sæther (homepage)
Centre for Conservation Biology (CCB)
Department of Biology
Norwegian University of Science and Technology