The ability to share resources for the benefit of all members of a group may have driven ancient organisms to evolve from a unicellular to a multicellular state.

The transition to the aggregative stage of Capsaspora owczarzaki, a close unicellular relative to Metazoa, is associated with significant upregulation of orthologs of genes that are important for multicellularity in metazoans.

Experimentally reconstructing the evolution of the molecular complex that animals use to orient the mitotic spindle establishes a simple genetic and physical mechanism for the emergence of a function essential for multicellularity.

Cancer is a consequence of the release of basal cellular functions inherited from our unicellular ancestors from the control of regulatory networks that evolved during the emergence of multicellularity.

Biofilm formation by Bacillus subtilis relies on a sensing mechanism for the amino acid serine that does not depend on a dedicated protein or RNA.

The gene regulation mechanisms necessary for the development of complex multicellular animals have been found in sponges.