Starvation in rotifers: Physiology in an ecological context

Abstract

Planktonic rotifers live in a world where food abundance can change rapidly and where food limitation is common and sometimes extreme. The goal of this review is to synthesize the ecological importance of food limitation in nature with the physiological responses of rotifers to starvation in the laboratory. Different rotifer species have very different responses to starvation. Some species respond to food deprivation by decreasing their metabolic rate and curtailing reproduction, while other species maintain a constant metabolic rate and continue to produce eggs, essentially reproducing themselves to death. This tradeoff between survival and reproduction explains much of the several-fold range in starvation times of different rotifer species. Future research is needed on the chemical composition of energy reserves in rotifers, the patterns of allocation of those reserves during starvation, and the frequency of starvation episodes in nature.