Neutral competition in a deterministically changing environment: Revisiting continuum approaches

Area of Science:

• Ecology
• Evolutionary Biology
• Mathematical Biology

Background:

• Environmental variation is crucial in ecological competition, altering species' relative advantages.
• Classical population models often assume constant environments, limiting their applicability to dynamic ecological scenarios.

Purpose of the Study:

• To investigate the impact of periodic environmental fluctuations on species competition using an extended competitive Moran model.
• To analyze how fluctuation magnitude and frequency influence fixation probability and mean fixation time.

Main Methods:

• Extension of the classical competitive Moran model to include a time-periodic environment.
• Adaptation of existing analytical methods to study the modified model.
• Investigation of fixation probability and mean time to fixation under varying environmental fluctuation parameters.

Main Results:

• At low fluctuation frequencies, the system resembles a constant fitness model.
• At high fluctuation frequencies, the system approximates a neutral competition model.
• Intermediate fluctuation frequencies reveal complex, non-trivial system dynamics.

Conclusions:

• Periodic environmental fluctuations introduce unique dynamics into competitive ecological models.
• The developed methods simplify mathematical analysis for stochastic competitive models.
• Findings align with recent theoretical work on stochastically changing environments.