ABSTRACT
The process through which prokaryotes are related to eukaryotes is still the subject of much debate. No genome-wide analyses have been published that would resolve the issue to everyone’s satisfaction. Methods of genome analysis that can recover non-Darwinian processes of genome evolution, such as lateral gene transfer and endosymbiosis, are needed to obtain an overview of the history of microbial life, but such methods are only just now in development. The ubiquity of mitochondria among all eukaryotes studied so far suggests that endosymbiosis might have had more to do with the prokaryote-to-eukaryote transition than is currently assumed.
