An Experimental Validation Test of Ecological Coexistence Theory to Forecast Extinction Under Rising Temperatures

Area of Science:

• Ecology
• Ecological Theory
• Global Change Biology

Background:

• Forecasting ecological community responses to global changes is challenging due to complex species interactions.
• Coexistence theory provides a framework for understanding species persistence under competition.
• Multigenerational validation of coexistence theory for predictive purposes is limited.

Purpose of the Study:

• To test the predictive power of modern coexistence theory in forecasting species extirpation.
• To assess the impact of rising temperatures and interspecific competition on species persistence.
• To validate coexistence theory using a replicated mesocosm experiment.

Main Methods:

• A highly replicated mesocosm experiment was conducted.
• Species extirpation time was monitored under rising temperatures and competition from a heat-tolerant species.
• Coexistence theory models were used to predict the point of coexistence breakdown.

Main Results:

• Interspecific competition accelerated species extirpation.
• Modelled coexistence breakdown aligned with observed extirpation times under steady and stochastic temperature increases.
• The theory captured the interactive effects of stressors, but predictive precision was low.

Conclusions:

• Coexistence theory can provide insights into the drivers of ecological change.
• The study supports the cautious application of coexistence modeling for ecological forecasting.
• Further refinement of coexistence theory is needed to improve predictive accuracy in complex systems.