In 1650, Francesco Redi, an Italian physician, proved that maggots come from living flies and not from lifeless meat as was widely believed. Louis Pasteur, who demonstrated that bacteria can only come from living bacteria. Pasteur never dreamed that the widely discredited evolutionary ideas of his contemporary, Charles Darwin, would one day become widely accepted by the scientific community, reviving once again the notion of spontaneous generation. Some evolutionists even insist that life must have independently evolved more than once on earth. Most evolutionists are confident that life has evolved many times in many other places in the universe.
Evolutionists speculate that life gradually evolved from mere hydrogen in a series of stages.
With time and energy, hydrogen transformed into all the other chemical elements. Then, about 4 billion years ago, the earth's atmosphere consisted of methane, ammonia, hydrogen and water, from which life would inevitably evolve. During stage two it is believed that simple chemicals from stage one formed the small organic molecules essential to life such as sugars, amino acids and nucleotides. Stage three in chemical evolution is supposed to have involved the stringing together of small organic molecules into long chain-like molecules called polymers . In fact, about the only similarity between microspheres and living cells is they are, as their name implies, small and spherical.