Generic criticality in a model of evolution

Area of Science:

• Complex Systems
• Theoretical Biology
• Statistical Physics

Background:

• Biological evolution models often exhibit distinct active and absorbing phases.
• Understanding the transitions between these phases is crucial for theoretical biology.
• Nonextremal dynamics introduce unique behaviors in evolutionary models.

Purpose of the Study:

• To investigate the phase transitions in a biological evolution model driven by nonextremal dynamics.
• To characterize the critical phase separating active and absorbing states.
• To determine the universality class of the observed critical point.

Main Methods:

• Monte Carlo simulations were employed to model the biological evolution.
• Analysis focused on the density of active sites (rho(t)) and survival probability (P(t)).
• Finite-size analysis was used to support the classification of the critical point.

Main Results:

• A critical phase was identified, separating active and absorbing phases.
• In the critical phase, rho(t) and P(t) decay as t(-delta) with delta approximately 0.5.
• The critical point separating active and critical phases shows delta approximately 0.29, suggesting a parity-conserving universality class.

Conclusions:

• The studied model exhibits a critical phase with distinct scaling behavior.
• The critical point aligns with the parity-conserving universality class.
• The model possesses infinitely many absorbing states and limited conservation laws.