Dr. Bob Rex, Scripps Institution of Oceanography
"How cyanobacteria invented biomineralization"
Cyanobacteria appear to have originated chlorophyll and undertaken successfully the oxygenation of the Earth. This initially oxidized vulnerable molecules and precipitated a number of the components of the ocean completely changing its chemistry and biological environment. After removing barium,iron, manganese, and much of the silica cyanobacteria discovered how to nucleate the crystallization of calcium carbonate. They are still doing this today creating stromatolites, a black biogenic rock of the intertidal zone with close affinity to 3.5 billion year old ancestors. Scripps Line Island Cruise II sampled modern stromatolites at Millennium Atoll and our cultures of these and similar stromatolites from other areas discloses how a group of 5 cyanobacteria and their phages introduced calcium carbonate mineralization.