Scientists have formulated many theories about the origin of life and how it evolved into the various forms known today. These ideas come from the evidence of the fossil record, from laboratory simulations of conditions on the earth, and from consideration of the structure and function of cells. The earth was created more than 4 billion years ago, although more than 2 billion years probably passed before life was developed. Scientists believe that the atmosphere of the …showed first 75 words of 1032 total…

…showed last 75 words of 1032 total…returned to their normal modes. However, some 40,000 of the invading bacteria were still present within each of the surviving amoebas! Through transplanting experimentation, Jeon found that the nucleus of the amoebas could not live without the once pathogenic bacteria. Jeon's accidental discovery proves that it is possible for an organism to become dependent on and a functional part of invading organisms. Instead of eliminating competitors, evolution eliminated competition itself, forming the basis of symbiotic relationships.