Well if we did not spring forth from them then oxygen would not be considered anything beneficial to maintain. There is evidence that photosynthesis occurred without releasing oxygen as a waste product in other organisms. The fact is without oxygen there would be no need for higher complex life to emerge and evolve at all.
For the first 2 billions years these complex single celled organisms did just fine without us. The problem came in when the sun was growing stronger so they were either forced to learn to convert its energy which meant building an ozone layer to protect them in the process. This in turn affected their abundant supply of carbon that early earth had when it was forming the planet.
Creating a multicellular organism that allowed them to maintain the supply of chemical conversions that before naturally occurred from the planet was a solution to the problem.
The evidence of 2 HGT from two different species of single celled organisms confirms we were created by them. Another fact is that the mitochondria is a single celled organism with its own DNA that moved in our cells so it could control the whole respiration process tells you that they left nothing to chance. We are not an independent cell capable of living independently from single celled organisms.but they can be independent from us.
Another fact is without them in our digestive system we could not process the food efficiently to obtain all of the nutrients we need. Again they did not leave this important process up to us but manage it themselves inside of us.
Now if science is lying about this information that is currently being educated to the masses as a fact then science is no better than religions teaching us bullshit.
I explanation of natural selection and environment is responsible for evolution is weak in its explanation and it does not make any sense when you evaluate the whole picture from all areas of science.
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