Capital Breeders and Income Breeders among Lepidoptera: Consequences to Population Dynamics

Among Lepidoptera, populations of some species display outbreaks at irregular intervals, some show regular cycles, whereas densities of most species never reach extremely high values. In recent years, researchers have looked for correlations between life-history traits and different types of population dynamics (Nothnagle and Schultz 1987, Hunter 1991, Hunter 1995a) while others have generalized based on relatively few but well-studied cases (Price et al. 1990, Price 1994). The proximate reasons of changes in population density presumably are in the environment (Ruohomiki and Haukioja 1992) but these kinds of observations may have masked the importance of life-history x environment interactions. Here we emphasize the importance of adult feeding, a correlate of eruptive (sensu Price et al. 1990) and cyclic population dynamics among Lepidoptera which has deserved almost no attention until very recently (Miller 1996). Furthermore, we propose ecological and evolutionary explanations for the correlation.