Bacteria In Control Of Life, Death, & Evolution?

Bacteria have long been associated with pathology but only about 5% of the bacterial population are harmful pathogens. The other 95% of bacteria form a natural and necessary part of the microorganisms that inhabit planet Earth. Bacteria are essential to all life forms, and even healthy humans could not exist without bacteria in, and on, their bodies. Bacteria are recognized as the first organisms to proliferate on earth, and all life forms are descended from them. Why are bacteria residents, or attached to, every life form? What role do they carry out that no organism can thrive or survive without them?

   Throughout the evolution of all the organisms that inhabit planet Earth, it appears that bacteria have maintained control of each organism in its methods of replication, in how its nutrients are obtained and absorbed, in how its respiratory and metabolic pathways are directed, all the while creating appropriate shelters so that each organism is protected and can survive in instances of adversity. In times of nutrient and energy shortages, bacteria become pathogenic by emitting toxins in order to reduce their population. However, the toxins can also be used to remove anything that threatens the survival of the bacteria.

   Bacteria were the only form of life for 80% of earth’s time-line. Although many life forms have evolved since then, the number of bacteria on our planet today “has been estimated at five to twenty-times the total mass of all animal life, both aquatic and terrestrial” (Postgate, 1992, p. 3). Bacteria appear to play an important role in every living organism from its inception, throughout its growth, and in its decay and death. No organism can grow and flourish without the presence of bacteria

   Homo Sapiens, through eons of time, have evolved from one-celled bacteria to our present multi-cellular form. However, like other life forms, our bodies still contain the original obligate anaerobe archaebacteria that lived in the deep oceans of planet earth between 3 and 4 billion years ago. Archaebacteria, the oldest life form as yet discovered on earth, still live within hot thermal vents on the ocean floor. They ingest inorganic chemicals for nourishment and energy, and excrete oxygen, lethal to anaerobes, as a waste product.

   In the early atmosphere of planet earth, the excreted waste created a build up of oxygen, and some archaebacteria evolved extra cell walls for protection from the lethal oxygen. The ozone layer, the protective covering that shields Earth from the dangerous ultraviolet rays of the sun, was created by the excess oxygen, and this allowed bacteria to emerge from the water and mineral deposits, and proliferate on land (Barghoorn, 1992). However, bacteria still sought endosymbiotic relationships within other life forms.

   Several questions arise. Why did bacteria proceed from an independent free floating existence to a dependent state in a larger life form? Why is it necessary for plant and animal life to contain trillions of bacteria? Is it possible that during the changing earth’s atmosphere from a presence of less than 1% oxygen to approximately 21% oxygen, the anaerobic archaebacteria created increasingly complicated shelters to protect themselves in order to survive in a constantly changing atmosphere?

   Further, as a result of the changing atmosphere, are all life forms on the planet Earth, including marine life, fungi, plants, animals, and humans, in reality those increasingly complicated evolved shelters? Have bacteria reached their ultimate goal? Have these microscopic creatures finally created a shelter in a human form that is now capable of producing the means of returning the atmosphere to less than 1% oxygen through pollution; an ever enlarging hole in the ozone layer; or a nuclear winter in which only anaerobic bacteria can survive to live in an independent state again?