Eco-evolutionary dynamics in competitive systems: Rescue and murder

Rapid evolution in response to changing environments can have beneficial (e.g. evolutionary rescue) or detrimental (e.g. evolutionary suicide) outcomes for the survival of one species. Responses of multi-species systems are even harder to predict, but important to consider. We simulate eco-evolutionary dynamics in one- and two-species systems, with two traits per species: physiological performance (associated with abiotic pressure) and defense against interference competition (associated with biotic pressure). In the single-species system, evolution is consistently beneficial, enabling evolutionary rescue. In contrast, in the two-species system, evolution can be simultaneously beneficial and detrimental, because rescue of one species can lead to evolutionary murder of the other. Notably, the pattern of rescue and murder was largely independent of different ecological and evolutionary scenarios, indicating that evolutionary murder might be common in competitive systems. Our study enables exploration of eco-evolutionary dynamics in more complex biotic settings, extending understanding of species responses to abiotic and biotic changes.