While it is key to the study of evolution to develop a theory to explain how species can change over time, it must also be supported by evidence from the scientific study of the natural world. One of the difficulties faced by many theories, such as Lamarck’s, was a lack of such evidence. Even Darwin's theory, which is the most widely accepted today, had to be proved with scientific advances and fossil evidence in …showed first 75 words of 655 total…

…showed last 75 words of 655 total…in turn, killed off intolerant forms and allowed for aerobic respiration. The result was a changed environment so abiotic polymerization could not occur. As O3 formed, high-energy source was no longer available. Basically, the origin of life is still evolving in itself. There are many views of how life actually began, how it grew, and how it will end, and each theory has much merit. With the growth of scientific technology, these theories will advance.