The article reports on the results of a study which determined the common ancestor of Melainabacteria and Cyanobacteria. It cites that the study describe a candidate sibling phylum, Melainabacteria, by searching for sequences that are related to Cyanobacterial genes from sequenced DNA, human faecal samples, and groundwater aquifer. It notes that Melainabacteria and Cyanobacteria are closely related but distinct in terms of the capacity to fix nitrogen, photosynthetic genes, and protein coding.