Darwin's Theory of Natural Selection

Charles Darwin revolutionized biology when he introduced The Origin of Species by Means of Natural Selection in 1859. Although Wallace had also came upon this revelation shortly before Origins was published, Darwin had long been in development of this theory. Wallace amicably relinquished the idea to Darwin, allowing him to become the first pioneer of evolution. Darwin was not driven to publish his finding, which he'd been collecting for several years before Wallace struck upon it, because he had "never come across a single [naturalist] who seemed to doubt to permanence of species" (Ridley, pp. 70). What follows are the key points of Darwin's Theory of Natural Selection taken directly from the two chapters concerning it in his book Origins. In chapter III of Origins Darwin sets up his discussion on Natural Selection by establishing the struggle for existence in nature. By this he means not only an individuals need to fend of enemies and survive its environment but also it's ability to create living, healthy, successful offspring. The first factor concerning this struggle is the ratio of increase in any given species. Darwin explains how this struggle must be occurring otherwise a single species would dominate the entire earth because every single one of it's offspring would survive. This is due to the fact that every species reproduces exponentially, a rate that would soon produce astonishing numbers if left unchecked. This does not happen however, because nature has a system of checks and balances. Although we may not be able to detect these checks, we can see their effects by the indisputable fact that one species doesn't completely dominate the planet. These checks consist of enemies eating the young or even adults, the rigors of weather or environment, and countless others. In this way birds, for example, cannot populate beyond their food supply, and the grains they feed on are held in check, because even though they may produce thousands of seeds only a few

Bibliography: Darwin, Charles, The Origin of Species by Means of Natural Selection. New York, Random House Inc, 1859. Ridley, Mark, The Darwin Reader. New York, W. W. Norton and Co, 1987.