Offspring size plasticity in response to intraspecific competition: an adaptive maternal effect across life-history stages.

摘要: When provisioning offspring, mothers balance the benefits of producing a few large, fitter offspring with costs decreased fecundity. The optimal between size and fecundity depends on environment. Theory predicts that larger have advantages in adverse conditions, but favorable conditions is less important. Thus, if environmental quality varies, selection should favor adaptively allocate resources response to local maximize maternal fitness. In bryozoan Bugula neritina, we show intensity intraspecific competition dramatically changes size/performance relationship field. benign or extremely competitive environments, important, at intermediate levels competition, colonies from larvae higher performance than smaller larvae. We predicted produce when likely tested these expectations field by manipulating density brood colonies. Our findings matched expectations: produced high densities low densities. addition, high-density environments dispersal potential, which may enable escape crowded environments. It appears can adjust fitness, altering phenotype across multiple life-history stages.