The dynamic signature of communities undergoing evolutionary rescue

Background/Question/Methods

Due to unprecedented rapid global change, ecological communities are currently experiencing abrupt and sustained environmental stress. Populations and communities that cannot migrate or adapt physiologically may be extirpated. However, when analyzing the non-equilibrium dynamics that occur prior to and during the extinction process the potential of community rescue through adaptive evolution is generally neglected. Using multi-species model communities that display non-equilibrium dynamics we investigated how adaptive evolution can lead to rescue from extinction. We analyzed the dynamic signature (e.g., period and amplitude of oscillations) before, during, and after the rescue process and searched for general patterns that can serve as indicators that communities are undergoing evolutionary rescue.

Results/Conclusions

We found that trait evolution can allow community evolutionary rescue and ensure the community persists, e.g., by preventing competitive exclusion during environmental change. Community evolutionary rescue generally brings about a change in the character of non-equilibrium dynamics governing coexistence before and after environmental change. We were also able to show that a change in the character of community oscillations may be a signature that a community is undergoing evolutionary rescue. Our study extends the theory on evolutionary rescue to a world of non-equilibrium community dynamics and calls for an eco-evolutionary perspective when predicting extinction potential.