Self-Reproduction and Evolution in Cellular Automata: 25 Years after Evoloops

TL;DR

This paper reviews 25 years of research on self-reproduction and evolution in cellular automata, highlighting key developments, current challenges, and future directions in artificial life and open-ended evolution.

Contribution

It provides a comprehensive overview of progress and challenges in cellular automata-based self-reproduction and evolution research over the past 25 years.

Findings

Significant advancements in automata models of self-reproduction.

Recent resurgence of interest due to open-ended evolution.

Identification of key challenges and future research directions.

Abstract

The year of 2024 marks the 25th anniversary of the publication of evoloops, an evolutionary variant of Chris Langton's self-reproducing loops which proved constructively that Darwinian evolution of self-reproducing organisms by variation and natural selection is possible within deterministic cellular automata. Over the last few decades, this line of Artificial Life research has since undergone several important developments. Although it experienced a relative dormancy of activities for a while, the recent rise of interest in open-ended evolution and the success of continuous cellular automata models have brought researchers' attention back to how to make spatio-temporal patterns self-reproduce and evolve within spatially distributed computational media. This article provides a review of the relevant literature on this topic over the past 25 years and highlights the major accomplishments made so far, the challenges being faced, and promising future research directions.