Spatial and temporal population genetic structure of the butterfly Aglais urticae L-(Lepidoptera, Nymphalidae)

The genetic diversity and the temporal and spatial genetic population struc ture of the butterfly Aglais urticae, a highly mobile species, were studied by allozyme electrophoresis. High levels of allozyme diversity were found. Most of the total genetic diversity occurred at the within-population scal e rather than at the between-population scale. This variation could not be accounted for by Wright's model of 'isolation by distance'. No significant temporal variation was observed for those populations that were sampled in different years. A process combining high movement rate between neighbourin g patches, long-distance migration and rare extinction/recolonization is su ggested to explain the observed genetic structure. This hypothesis is favou red over an island model of population structure because migration in A. ur ticae is uniform neither with distance nor with time.