Physiological Constraints on Long-Term Population Cycles: a Broad-Scale View

Background: Long-term cycles in animal abundance impact the dynamics of most major ecosystems, yet the drivers of broad-scale variability in these cycles are unclear. Aim: Examine potential relationships between the period of long-term population cycles and key life-history traits (generation time and its primary determinants – body mass and body temperature) across a broad range of primary consumer taxa (protists, zooplankton, insects, mammals, and birds). Results: We find that long-term cycle periods vary predictably with generation time, body mass and temperature. Cycle periods decreased exponentially with increasing body temperature, and increased as a power law with increasing body mass. Conclusions: These scaling relationships appear more consistent with predictions from models of population dynamics based on maternal effects than with those based on specialized consumer–resource interactions. More generally, the results provide a basis for understanding how changes in the size structure of populations, or the environmental temperatures populations experience, may affect their dynamics.