Stromatolites are layered structures formed by the activities of prokaryotic organisms, primarily cyanobacteria. These cells are classified as photosynthetic bacteria, specifically within the domain of Archaea and Bacteria.
Cyanobacteria, often referred to as blue-green algae, are capable of photosynthesis, which allows them to convert sunlight into energy while producing oxygen as a byproduct. Over millions of years, the growth and accumulation of these microorganisms led to the formation of stromatolites, which are some of the oldest evidence of life on earth.
In summary, the prokaryotic cells that built stromatolites are primarily classified as cyanobacteria, and their role in the formation of these structures is a testament to the significance of microbial life in shaping our planet’s geological and biological history.