# Evolution of cooperation on an epithelium

## TL;DR

This paper compares the evolution of cooperation in epithelial tissue models, showing that cell mobility enhances cooperative success more than static population models, through simulations and analytical methods.

## Contribution

It introduces a dynamic epithelial model using Voronoi tessellation and demonstrates that cell movement promotes cooperation more effectively than traditional static models.

## Key findings

- Cell mobility in tissue models enhances cooperation.
- Voronoi tessellation model predicts higher fixation probabilities.
- Dynamic models outperform static graph models in cooperation promotion.

## Abstract

Cooperation is prevalent in nature, not only in the context of social interactions within the animal kingdom, but also on the cellular level. In cancer for example, tumour cells can cooperate by producing growth factors. The evolution of cooperation has traditionally been studied for well-mixed populations under the framework of evolutionary game theory, and more recently for structured populations using evolutionary graph theory. The population structures arising due to cellular arrangement in tissues however are dynamic and thus cannot be accurately represented by either of these frameworks. In this work we compare the conditions for cooperative success in an epithelium modelled using evolutionary graph theory, to those in a mechanical model of an epithelium =- the Voronoi tessellation model. Crucially, in this latter model cells are able to move, and birth and death are not spatially coupled. We calculate fixation probabilities in the Voronoi tessellation model through simulation and an approximate analytic technique and show that this leads to stronger promotion of cooperation in comparison with the evolutionary graph theory model.