Eco-evolutionary feedbacks can drive rate-induced regime shifts in ecosystems

Background/Question/Methods

Environmental change is occurring at unprecedented rates and is altering both ecological and evolutionary processes in natural ecosystems. The possibility that ecosystems can respond abruptly to gradual environmental change when critical thresholds are crossed (i.e. tipping points) and undergo an regime shift to an alternative stable state is a growing concern. Policy to prevent ecosystem regime shifts is based on a theoretical framework that have largely neglected evolutionary processes. The lack of an evolutionary perspective in ecosystem tipping theory has largely limited our capacity to understand and predict the occurrence of regime shifts.

Results/Conclusions

I will show that eco-evolutionary feedbacks introduce a novel type of tipping dynamics in ecosystems, specifically rate-induced tipping. This is a mechanism of tipping whereby an ecosystem can undergo a regime shift when the rate of change of an environmental condition exceeds a critical threshold. This mechanism contrast with the dominant paradigm in ecological theory based on Bifurcation-tipping, i.e. a mechanism whereby an ecosystem can undergo a regime shift only when the magnitude of an environmental condition exceeds a critical threshold. I furthermore show that the occurrence of rate-induced tipping in ecosystems depends on the difference in the timescales of ecological and evolutionary processes. Specifically, fast evolutionary change mediated by high trait variation can reduce the sensitivity of the ecosystem to the rate of environmental change and prevent the occurrence of rate-induced tipping. These findings suggest that management measures to prevent rate-induced regime shifts should focus on slowing down the pace of environmental change and protecting phenotypic diversity in ecosystems.