Life on Earth Before Oxygen: 2.5-Billion-Year-Old Bacteria Discovered

A bacteria fossil, which dates back to almost 2.5 billion years, has been discovered in one rock formation in Gamohaan, South Africa. Scientists are impressed as it is not like many of the bacteria and microorganisms found on Earth which thrive on the presence of oxygen, a proof that it is a microorganism that existed prior the "Great Oxidation Event" in which massive amounts of oxygen dissolved into the atmosphere.

This, for many scientists, is an impressive find. A study from Science Alert has shown that the ability of this microorganism to thrive without oxygen and use oxidized sulfur is a good thing. It is actually an indication that there are organisms that can survive in the event that the amount of oxygen in the atmosphere decreases at a significantly low amount.  

One of the scientific theories about biodiversity before what is known as the "Great Oxidation Event" is that oceans are filled with bacteria that can create food with neither sunlight nor oxygen. The discovery of this fossilized bacteria may be one evidence to prove that this theory may actually be true.

A study from the University of California explained that the sample was located and photographed by light microscopy and laser scanning microscopy, and they discovered that the size of the bacteria is larger than most of those present today. The size and shape gave the scientists a clue to what kind of bacteria this might be, as most sulfur-oxidizing bacteria are larger in diameter.

According to a study performed by the University of Cincinnati, the fossilized sample was dug up from a layer of hard, silica-rich rock found in the Kaapvaal Craton. This find is one in a million as it has been uncovered in one of the two places where Earth's crust from billions of years ago is still well preserved.