In 1859, Charles Darwin proposed that differential survival and reduction of individuals would produce changes in species population over time. In other words, the environment acting on variation of individuals within a population would result in an adaptation (an evolutionary process that results in morphological, physiological or behavioral changes at the population level and that increases the probability of the members of that population to survive and their reproductive success). Using a specific example, explain how natural selection explains the theory of evolution. Also include in your explanation and within your example, what are the 4 factors needed for natural selection to act