Abundance Distributions in Artificial Life and Stochastic Models: "Age and Area" revisited

TL;DR

This paper investigates the relationship between genotype age and abundance in artificial self-replicating systems, revealing a punctuated evolutionary pattern and proposing a stochastic model that captures observed distribution features.

Contribution

It demonstrates a correlation between genotype age and abundance, supports universality in distribution coefficients, and introduces a stochastic model explaining the dynamics of equilibrium periods.

Findings

Correlation between genotype age and abundance observed

Universal coefficients in genotype abundance distributions

Stochastic model accurately predicts observed distributions

Abstract

Using an artificial system of self-replicating strings, we show a correlation between the age of a genotype and its abundance that reflects a punctuated rather than gradual picture of evolution, as suggested long ago by Willis. In support of this correlation, we measure genotype abundance distributions and find universal coefficients. Finally, we propose a simple stochastic model which describes the dynamics of equilibrium periods and which correctly predicts most of the observed distributions.