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So far, so good. A review of our studies on evolution. 5.23.11 Charles Darwin, after 5 years as Naturalist aboard the HMS Beagle, began formulating what would be his major contribution to Science, Evolution by Natural Selection. Darwin’s travels to South America, Australia, the Pacific Islands and most importantly, the Galapagos Islands, made him think about how species are created. He had some experience with Artificial Selection, based on his interests in breeding pigeons and England’s fascination in dog breeding. Thomas Malthus’ writing on overpopulation, in regards to English social theory, made Darwin ponder the effect overpopulation has in nature. The “struggle to survive” seed had been planted. Charles Lyell’s writings on geology, and the slowly and constantly changing Earth, inspired Darwin to wonder if life must also slowly and constantly change. Darwin realized that he must understand Earth’s history to understand life’s history. As Sean B. Carroll stated “life forms are running to keep up, and most often don’t”. Extinction is the norm, not the exception. Darwin “sat” on his theory for over 20 years for a variety of reasons, such as worries of bringing dishonor to the Darwin name, the fact that his theory was heretical, the fact that his wife, Emma, was deeply religious, and that he was comfortably established within English society and he was worried to risk ruining his scientific fate. Alfred Russel Wallace independently hypothesized about Natural Selection and (luckily?) sent his paper directly to Darwin with a note to send along to Joseph Hooker to be sent to the Linnean Society. Wallaces essay was sent along with an abstract of Darwin’s book in what is now referred to as “the delicate situation”. Although Darwin was working on his ideas for decades, and “Wallace didn’t write anything Darwin didn’t already know”, Darwin and his friends had to scramble so Darwin didn’t lose priority. His book had 2 major ideas, “descent with modification” and “natural selection”. Evolution requires changes in regards to traits, selection and time. Recently, studies of rock pocket mice have demonstrated how natural selection works. With a small survival advantage black rock pocket mice can overtake a population in as little as 150 generations. Sean B. Carroll’s work on fruit fly’s and their wing spots have shown that having a gene isn’t necessarily the deciding factor in evolution. Expressing the gene, at a certain time and at a certain place, is just as important. Prof. Carroll discovered “genetic switches” which control the expression of genes into proteins.