The origin of eukaryotes is often viewed as a major transition in the history of life. In this talk, I will summarise recent progress in this area, including some recent work from the group that aims to determine the sequence of events (for example, mitochondrion- or nucleus-first) in the evolutionary assembly of eukaryotes. I will also present some new, rather exploratory, work that aims to understand when during the evolution of eukaryotes the shift from a prokaryotic evolutionary regime (characterised by large effective population sizes and strong selection) gave way to the more relaxed evolutionary mode of eukaryotes, and whether this might explain some of the developments in early eukaryotic evolution.

The talk is part of the Computational Approaches to Early Evolution Workshop (April 20-24, 2026)