How well can body size represent effects of the environment on demographic rates? Disentangling correlated explanatory variables

摘要: Demographic rates are shaped by the interaction of past and current environments that individuals in a population experience. Past shape individual states via selection plasticity, fitness-related traits (e.g. size) commonly used demographic analyses to represent effect on rates. We quantified how well size captures effects population's well-studied experimental system soil mites. decomposed these interrelated sources variation with novel method multiple regression is useful for understanding nonlinear relationships between responses multicollinear explanatory variables. graphically present results using area-proportional Venn diagrams. Our was developed combining existing methods expanding upon them. showed strength as proxy environment varied widely among vital For instance, this organism an income breeding life history, had more reproduction than size, but substantial overlap indicating encompassed some fecundity. This demonstrates can vary life-history processes within species, should be taken into consideration trait-based or individual-based approaches focus phenotypic state Furthermore, will depend what variable(s) rate being examined; is, different measures body length, volume, mass, fat stores) better worse proxies various processes.