Resource depression in Daphnia galeata, Daphnia cucullata and their interspecific hybrid: life history consequences

摘要: In this study, the effect of food concentration on several life history parameters Daphnia galeata, cucullata and hybrid between these two species was examined. The had a significant both growth reproduction all three taxa. Mortality highly specific, to lesser extent dependent concentration. Changes in resulted changes intrinsic rate population increase (r). dependence different found be different. relatively constant low r. r values for varied most, with compared parental when grown at levels high higher concentrations. Our results suggest that concentrations are will have selective advantage over species, but lower D.galeata an D.cucullata hybrid.