CONFIDENCE-REGIONS FOR EVOLUTIONARY TRAJECTORIES

We derive confidence regions for the evolutionary trajectories derived from a model of Via and Lande (1985, Evolution 39, 505-522). We utili ze a nested, parametric bootstrap to calculate the confidence regions and show that a likelihood-based approach provides an unsatisfactory s olution. We calculate the predicted evolutionary trajectories and conf idence regions using data from an experiment on pupal weight of Tribol ium beetles in two different flour types. With realistic sample sizes for experiments that estimate genetic parameters in multiple environme nts, the confidence regions are likely to be large, potentially limiti ng the ability to test hypotheses about evolutionary trajectories. The . problem may be less acute for trajectories of characters expressed i n only a single environment, because sample sizes can generally be lar ger than in multienvironmental studies.