Effects of a pestilent species on the stability of cyclically dominant species

TL;DR

This study investigates how introducing a pestilent species affects the stability of cyclically dominant species, revealing complex phase transitions and counter-intuitive extinction phenomena that challenge traditional views on biodiversity maintenance.

Contribution

The paper introduces a fourth pestilent species into a cyclic dominance model and uncovers multiple phase transitions and unexpected extinction outcomes, expanding understanding of species coexistence.

Findings

Identified three phase transitions as pestilent species invasion strength varies.

Found that pestilent species can lead to its own extinction despite supporting coexistence.

Revealed counter-intuitive effects where pestilent species extinction enhances overall system stability.

Abstract

Cyclic dominance is frequently believed to be a mechanism that maintains diversity of competing species. But this delicate balance could also be fragile if some of the members is weakened because an extinction of a species will involve the annihilation of its predator hence leaving only a single species alive. To check this expectation we here introduce a fourth species which chases exclusively a single member of the basic model composed by three cyclically dominant species. Interestingly, the coexistence is not necessarily broken and we have detected three consecutive phase transitions as we vary only the invasion strength of the fourth pestilent species. The resulting phases are analyzed by different techniques including the study of the Hamming distance density profiles. Some of our observations strengthen previous findings about cyclically dominant system, but they also offer new revelations and counter-intuitive phenomenon, like supporting pestilent species may result in its extinction, hence enriching our understanding about these very simple but still surprisingly complex systems.