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1media/blue green algae in rankin lake sequin patrick brinksma.jpg2019-04-07T22:30:46-07:00Sam Henrickson5cd0ff97c337b26d01e84db58bdb9506b40fff7a335197Xplain2019-04-20T18:59:39-07:00Sam Henrickson5cd0ff97c337b26d01e84db58bdb9506b40fff7aXThe imperative working aspect of X with regard to bacteria is the concept of an irreversible change that occurs upon its discovery. It is difficult to find evidence of a connection that fits well with the concept of X and bacteria, but with regard to a forced, uncontrollable subjectification of an entire species by an unknown, unpredictable source, bacteria has one that is concrete: oxygen.
The beginning of the Archean age was marked by the discovery of fossilized microorganisms that were found in hydrothermal vent precipitates. This volcanic soup was, to the best of our limited knowledge, the beginning of all life on earth. It was single-celled prokaryotes, which is a classification of unicelled organisms that lack organelles. They are the simplest concoction of DNA, with a single circle-shaped chromosome that consume base elements like ammonia and nitrite. Then, what is likely the ancestor of the only type of bacteria to photosynthesize and create oxygen as a byproduct called cyanobacteria began photosynthesizing somehow, creating tiny amounts of oxygen that were not ever free in the atmosphere of the world, thanks to the immense amounts of iron that used it all up in mass rusting, creating massive banded iron formations at the bottom of the ocean.
This continued until the beginning of the Proterozoic eon, when something happened, after the iron in the atmosphere was used up. The continued creation of oxygen by the cyanobacteria when it had nowhere to go set off a set of events referred to as the Great Oxygenation Event, which killed off many of the class of microorganisms called obligate anaerobic organisms, to whom any significant amount of oxygen is toxic. The oxygen also would have reacted with the enormous concentration of methane gas in the atmosphere, freezing the earth over for the longest period in history. This forced the life on Earth to find an equilibrium, and settled the oxygen to a tolerable amount as it evolved in a brand new, oxygenated world.
