Dynamics of populations in a changing environment

Area of Science:

• Evolutionary Biology
• Population Dynamics
• Computational Biology

Background:

• Environmental changes pose significant challenges to population survival.
• Mutations and selection are key evolutionary forces influencing population dynamics.
• Understanding population responses to environmental shifts is crucial for ecological and evolutionary studies.

Purpose of the Study:

• To develop and analyze an individual-based model of a population in a fluctuating environment.
• To investigate the impact of mutation rate and selection pressure on population survival and extinction.
• To characterize the phase transition between population survival and extinction.

Main Methods:

• An individual-based modeling approach was employed.
• Monte Carlo simulations were utilized to explore population dynamics.
• The model incorporated mutation and selection as core evolutionary pressures.

Main Results:

• A continuous phase transition was identified between an active (survival) and an absorbing (extinction) phase.
• Weaker selection allowed populations to inhabit all available space.
• Stronger selection drove populations to optimal living conditions, avoiding harsher environments.
• The mean time to extinction was found to depend on the mutation rate.

Conclusions:

• Population fate (survival or extinction) is critically dependent on the interplay between mutation rate and selection intensity.
• Environmental conditions and selection pressure dictate population distribution and persistence.
• The study provides insights into the evolutionary stability and extinction dynamics of populations facing environmental change.