Who or what is responsible for the occurrence of life on earth, and possibly many other planets, is a question that has plagued humanity for thousands of years. Once life was present on the planet, scientists largely agree that natural selection, the theory presented by Charles Darwin, took place allowing the hundreds of various species to emerge from one common ancestor known as the last universal common ancestor (LUCA) (Christian, Brown & Benjamin 2013, p. 57). Theories of how life actually came into being include; life began with a spark from electricity, which can generate the amino acids and sugars necessary for life to form (Choi, 2011); RNA provides the missing link between non-life chemicals and living cells (Emspak, 2015); or perhaps
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By gaining an understanding and examining evidence associated with each of these three theories it becomes clear that the most logical and truthful of the three is the theory of Chemical Evolution. Before delving directly into the first theory, one must understand Darwin’s theory of natural selection because it is a theory that the majority of scientists take to be true. The scientific community agrees on natural selection because the evidence for it is provable and indeed happening before their very eyes. DNA molecules copy themselves almost perfectly, but the mutations that do occur allow the life form to evolve and change with its surroundings. Artificial selection, especially in the example of domesticated dog breeds, has allowed scientists to observe first hand natural selection taking place at an accelerated rate. Dogs that had a slightly stronger inclination to herd other animals were breed with each …show more content…
The Miller-Urey experiment recreated the conditions of a primeval Earth, and Steve Miller reported that these conditions “had produced the chemicals that were essential for life to begin” (Peet, 2015) . Although it has been found that the earth’s early atmosphere may have much less hydrogen than originally hypothesized, it is thought that volcanic clouds, which would have the ideal conditions necessary, may have been the breeding ground for these first life-giving molecules. The Miller-Urey experiment, and thus entire theory, however, is based upon the assumption that the early earth did not have oxygen in its atmosphere. This assumption seems logical because oxygen’s high reactivity would destroy almost any organic material needed to create life, and it has also been shown that oxygen was likely not part of the earth’s atmosphere until around 2.5 billion years ago with the creation of photosynthetic bacteria (Christian, Brown & Benjamin 2013, p. 65). Scientists continue to come closer and closer to producing life in a controlled laboratory setting, and when they do it could revolutionize the current theories about origins of life and the earth’s early
By gaining an understanding and examining evidence associated with each of these three theories it becomes clear that the most logical and truthful of the three is the theory of Chemical Evolution. Before delving directly into the first theory, one must understand Darwin’s theory of natural selection because it is a theory that the majority of scientists take to be true. The scientific community agrees on natural selection because the evidence for it is provable and indeed happening before their very eyes. DNA molecules copy themselves almost perfectly, but the mutations that do occur allow the life form to evolve and change with its surroundings. Artificial selection, especially in the example of domesticated dog breeds, has allowed scientists to observe first hand natural selection taking place at an accelerated rate. Dogs that had a slightly stronger inclination to herd other animals were breed with each …show more content…
The Miller-Urey experiment recreated the conditions of a primeval Earth, and Steve Miller reported that these conditions “had produced the chemicals that were essential for life to begin” (Peet, 2015) . Although it has been found that the earth’s early atmosphere may have much less hydrogen than originally hypothesized, it is thought that volcanic clouds, which would have the ideal conditions necessary, may have been the breeding ground for these first life-giving molecules. The Miller-Urey experiment, and thus entire theory, however, is based upon the assumption that the early earth did not have oxygen in its atmosphere. This assumption seems logical because oxygen’s high reactivity would destroy almost any organic material needed to create life, and it has also been shown that oxygen was likely not part of the earth’s atmosphere until around 2.5 billion years ago with the creation of photosynthetic bacteria (Christian, Brown & Benjamin 2013, p. 65). Scientists continue to come closer and closer to producing life in a controlled laboratory setting, and when they do it could revolutionize the current theories about origins of life and the earth’s early