GoKawiilResearch review maps how life repeatedly evolved multicellularity across 45 lineages
A body of recent research, including a 2023 phylogenetic survey and a 2025 study on archaea, documents that multicellularity has arisen independently at least 45 times across the tree of life, spanning bacteria, archaea and eukaryotes. The studies identify six distinct structural types of simple multicellularity and show that even archaea, previously thought incapable of complex tissue-like organization, can form clonal multicellular structures under mechanical compression. Together these findings are organized under a newer conceptual framework that treats multicellularity as a continuum of evolutionary stages rather than a single fixed trait.