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Nick Wright Anthropology Research Report Charles Darwin’s Theory of Natural Selection Charles Darwin is known for his major contributions to evolutionary science, primarily for his development of the theory of evolution. A critical part of his theory of evolution is the concept of natural selection, which states “those individuals with favorable variations would survive and reproduce, but those with unfavorable variations would not”. The purpose of this paper will be to give a brief history of Charles Darwin, details on his discovery to the Theory of Natural Selection, and then finally an analysis of how the theory can affect a species, and a specific example of natural selection occurring. Charles Darwin was born on February 12, 1809 in Shrewsbury England, to a family of wealth and higher education. Originally he had planned to follow in his father’s footsteps to practice medicine, but the medical field didn’t capture his interest well enough to pursue this endeavor. From there, he enrolled at Christ’s College of Cambridge to study theology, were he didn’t feel satisfied with this field of study either. After leaving Cambridge in 1831, this is where his journey towards becoming a naturalist and an exploratory scientist first began. John Henslow, Professor of Botany at Cambridge, had recommended him for a position on a British Navy survey vessel, known as the HMS Beagle. This opportunity began his famous 5 year voyage, in which he sailed to South America, as well as other islands in the Pacific Ocean including the Galapagos Islands. The journey to the Galapagos Island’s is known as a major influential factor that helped guide Darwin to develop his theory of Natural Selection. It was here, that Darwin began to make observations of the large variation in vegetation and animal species. He began to notice slight differences in traits from species located on isolated islands, compared to species he studied on the South American mainland. His big break through came from studying the similarities and differences between traits of birds from island to island, specially finches. It was here in the Galapagos Islands off the coast of Ecuador that Darwin collected 13 different types of finches, to analyze the differences and similarities based on geographic location. He was interested in the fact that the finches were similar enough to be categorized in a related group, but still showed distinguishable different physical traits like beak size and shape, that differed depending on which island or mainland they were collected from. The research he gathered from further analysis of the Galapagos finches lead him to realize that the finches must have descended from a common ancestor, but somehow overtime their traits had changed in accordance to what made them more capable to survive in a specific environment. Along this journey, he also made notes discussing two different types of iguanas that had appeared to have evolved from the same species, each one possessing specific traits allowing them to survive in their different types of habitats. It was from these observations that Darwin realized that certain individuals had a variation that gave them an advantage, this advantage allowed them to successfully reproduce and pass the traits on to their offspring’s. This is where the origins of Natural Selection occurred, and Charles Darwin began to work toward an evolutionary break through (Darwin 27-28). . Natural selection in its simplest form is survival of the fittest, stating that when change in an environment occurs, those individuals that posses a “better” trait will survive and the others will die out. This overtime will eventually lead to the formation of a new species. This process of natural variation of traits is not to be confused with, artificial selection, which is when humans manage the process of selecting preferable traits to be reproduced within a species. The basic process of natural selection works under the idea that in any species, more individuals are produced by reproduction than can survive within the resources their environment provides. This creates competition due to limited access to resources. Individuals within the species that have variation in certain traits lead to an advantage over others for accessing these resources; this is defined as “fitness”. It is important to keep in mind that the environment that the species lives in decides on what traits are beneficial. Next the principle of inheritance comes into play, when favorable traits are passed down to offspring’s of the next generation. This is what leads to advantageous traits becoming more common in a population, and less favorable characteristics become less common due to lack of survival. Eventually, over multiple generations of inheritance, a new species will appear. This cycle of natural selection and inheritance of beneficial traits is a crucial part in Darwin’s theory of evolution, and explains why some members of the species survive over others without certain favorable traits. One of the examples commonly associated with Darwin’s theory of natural selection has to do with the evolution of color between moths in England during the nineteenth century. The basics of the story involve the change in characteristics of the moths due to environmental factors. Originally, pale colored moths where most common due to the trait of camouflage while resting on light colored lichen-covered tree trunks. Due to new forms of pollution in the nineteenth century like coal dust and fireplaces, the trees began to turn a dark gray, exposing the pale moths to be eaten by birds. As birds switched from eating mainly dark moths, to mostly eating pale moths, the common color of moths changed from pale to dark. This occurrence of Natural selection resulted with the overall change in color of the British moth population. So in conclusion, Charles Darwin’s theory of Natural Selection is based on the idea that individuals within a species compete with each other for resources, and that individuals with favorable traits are more likely to survive and reproduce more off springs. This repeated inheritance of favorable traits over multiple generations eventually leads to favorable traits becoming more common, and overtime can lead to the development of a new species. His theory of natural selection can be generally broken down to 5 different assumptions, beginning with a struggle for existence within a population. Second, variation in a population creates different characteristics of individuals. Third, certain individuals have favorable traits, which increase their ability to survive and reproduce. Fourth, inheritance of favorable traits are passed down to the offspring’s of future generations. Finally, over a large period of time, variations in the population eventually lead to the formation of a new species. Work Cited Darwin, Charles. Charles Darwin's Natural Selection: Being the Second Part of His Big Species Book Written from 1856 to 1858. Paperback. Cambridge University Press, 1987. 27-28. Print. Guffey, Dr. Stan. "A Brief History of Charles Darwin."Darwin Day, Univ. TN Knoxville. n.d. n. 5-7. Print. Houghton Mifflin Harcourt Publishing Company, Charles Darwin's Natural Selection. The American Heritage® Science Dictionary, 2010. Print. Klappenbach,, Laura. "An Introduction To Evolution." About.com Animals / Wildlife. Web. 28 Apr. 2013.