This explains many things about evolution and how life began...

Below are excerpts which explain factual observations which can explain how life began on earth...


Cyanobacteria


   Cyanobacteria include unicellular and colonial species. Colonies may form filaments, sheets or even hollow balls. Some filamentous colonies show the ability to differentiate into several different cell types: vegetative cells, the normal, photosynthetic cells that are formed under favorable growing conditions; akinetes, the climate-resistant spores that may form when environmental conditions become harsh; and thick-walled heterocysts, which contain the enzyme nitrogenase, vital for nitrogen fixation. Heterocysts may also form under the appropriate environmental conditions (anoxic) wherever nitrogen is necessary. Heterocyst-forming species are specialized for nitrogen fixation and are able to fix nitrogen gas into ammonia (NH3), nitrites (NO-2) or nitrates (NO-3) which can be absorbed by plants and converted to protein and nucleic acids [atmospheric nitrogen cannot be used by plants directly]. The rice paddies of Asia, which produce about 75% of the world's rice[6] could not do so well were it not for healthy populations of nitrogen-fixing cyanobacteria in the rice paddy fertilizer.

   Many cyanobacteria also form motile filaments, called hormogonia, that travel away from the main biomass to bud and form new colonies elsewhere. The cells in a hormogonium are often thinner than in the vegetative state, and the cells on either end of the motile chain may be tapered. In order to break away from the parent colony, a hormogonium often must tear apart a weaker cell in a filament, called a necridium. (http://en.wikipedia.org/wiki/Cyanobacteria)

Marine phages

   Marine phages, although microscopic and essentially unnoticed by scientists until recently, appear to be the most abundant and diverse form of DNA replicating agent on the planet. There are approximately 4x1030 phage in oceans or 5x107 per millilitre.[4] They appear to influence biogeochemical cycles globally, provide and regulate microbial biodiversity, cycle carbon through marine food webs, and are essential in preventing bacterial population explosions.[5] Scientists are exploring the potential of marine cyanophages to be used to prevent or reverse eutrophication.
[edit] In sediments

   Marine bacteriophage form an important part of deep sea ecosystems. There are between 5x1012 and 1x1013 phage per square metre in deep sea sediments and their abundance closely correlates with the number of prokaryotes found in the sediments. They are responsible for the death of 80% of the prokaryotes found in the sediments, almost all of these deaths are caused by cell lysis (bursting). They therefore play an important part in shifting nutrients from living forms into dissolved organic matter and detritus. This explains the high rate of nutrient turnover in deep sea sediments, the release of nutrients from infected bacteria stimulates the growth of uninfected bacteria and then these also become infected. Because of the importance of deep sea sediments in biogeochemical cycles marine bacteriophage must influence the carbon, nitrogen and phosphorus cycles but the exact influences are currently not understood.[4]   (http://en.wikipedia.org/wiki/Marine_bacteriophage)


   The first single cells to form converted elements into organic compounds, and as the environment changes as a result, the organisms in it change. Eventually concentrations get too high and everything changes. New organisms are developed (step by step), producing new organic compounds, and everytime another over-concentration is reached, everything changes to accommodate. Everytime these catastrophic changes occur the surviving organisms adapt and reach a new balance which usually prevents the same disaster from repeating. 
   Notice how the two organisms balance each other out, and provide the first level of organic compounds from which all other more complex life has spawned. Notice how the one species can diverge into several, symbiotic types, functioning as a more complex whole. When the environment suits it, the organisms can continue growing and advancing.
   It is the changes in the environment which drive the changes in the organisms, which drive more changes in the environment and so on, until you have animals with brains, and imaginations (us). We may be the end of the line if we destroy our environment. Either that or maybe we will colonize other planets.