Temporal assortment of cooperators in the spatial prisoner's dilemma

TL;DR

This paper investigates how temporal strategies influence cooperation in spatial prisoner's dilemma models, revealing that cooperation can evolve and dominate across various network structures even under challenging conditions.

Contribution

It introduces a model where organisms choose when to cooperate, showing that temporal assortment promotes cooperation across different network topologies.

Findings

Cooperators reach fixation more often with added time slots.

Cooperation increases in scale-free networks despite unfavorable benefit-cost ratios.

Temporal strategies enhance cooperation beyond traditional spatial models.

Abstract

We study a spatial, one-shot prisoner's dilemma (PD) model in which selection operates on both an organism's behavioral strategy (cooperate or defect) and its choice of when to implement that strategy across a set of discrete time slots. Cooperators evolve to fixation regularly in the model when we add time slots to lattices and small-world networks, and their portion of the population grows, albeit slowly, when organisms interact in a scale-free network. This selection for cooperators occurs across a wide variety of time slots and it does so even when a crucial condition for the evolution of cooperation on graphs is violated--namely, when the ratio of benefits to costs in the PD does not exceed the number of spatially-adjacent organisms.