---
title: "Major Evolutionary Transition"
description: "Maynard Smith and Szathmáry's term for the rare moments when formerly independent replicators become a larger entity that replicates only as a whole, with division of labor among the parts and a new medium of information storage and transmission."
type: "glossary-term"
canonical_url: "https://antikythera.wiki/terms/major-evolutionary-transition"
md_url: "https://antikythera.wiki/md/terms/major-evolutionary-transition"
last_updated: "2026-09-06"
site: "Antikythera Wiki"
---

# Major Evolutionary Transition

> A working definition written for this wiki from the reading notes; not Antikythera's own wording. From Antikythera Wiki (https://antikythera.wiki/terms/major-evolutionary-transition), an independent guide to Antikythera's published work.

Maynard Smith and Szathmáry's term for the rare moments when formerly independent replicators become a larger entity that replicates only as a whole, with division of labor among the parts and a new medium of information storage and transmission. Agüera y Arcas treats every MET as symbiogenesis (bff exhibits all three criteria), extends the list past language to agrarian, urban and industrial transitions, and frames AI as the latest: a symbiosis of human and electronic predictors in which, for the first time, higher-order modeling leaves human skulls. Transitions accelerate because better predictors are better learners. Earlier entities persist — eukaryotes did not replace bacteria — which underwrites the book's anti-replacement optimism.

## Appears in

- [What Is Intelligence?](https://antikythera.wiki/work/substack/2025-11-18-what-is-intelligence) (2025-11-18)
- [What Is Intelligence?](https://antikythera.wiki/work/book/what-is-intelligence) (2025-09-23)
- [Infinity Mirror](https://antikythera.wiki/work/journal/infinitymirror) (2025-05-10)
- [Antikythera](https://antikythera.wiki/work/journal/research) (2025-05-10)

_Glossary generated 2026-09-06._