Evolution and Natural Selection Essay Example | Topics and Well Written Essays - 1250 words

Evolution and graphic choice - Essay ExampleHowever in the mid-nineteenth century, scientist like Charles Darwin and Alfred Wallace sought-after(a) to explain this process of adaptation and change as a natural one without attributing it to the influence of higher beings and spiritual powers. Fossil records are perhaps the outgo natural evidence of evolution. While the fossils of simpler organism are found among older rocks, the newer ones urinate fossils of more complex organisms.. (GCSE, BBC)Evolution is of 2 main types Microevolution and macroevolution. Microevolution emphasises on contractable change from one generation to another while macroevolution deals with the process of gradual change in the physical form of living creatures. (The Process of Speciation, Global revision Program, University of Michigan)This paper will focus on the theory of evolution put forth by Charles Darwin. Key aspects of evolution like the process of Natural Selection and Variation will be discuss ed. Also, with reference to reference to Darwins finches, the paper will describe how geographical isolation has caused new species to evolve from a common sourceDarwin was influenced by observations made during his voyage as naturalist on the survey ship Beagle. After studying several plant and animal species, Charles Darwin published around of his key observations and ideas in his book, The Origin of Species. His theory of evolution comprises 4 parts1. As fossils records maneuvers the world is constantly changing. Several organisms have become extinct and others have changed over time are are rather different from their previously existing forms. 2. All organisms share a common ancestor and hence sure common features.3. The process of change is a gradual one4. The mechanism of evolutionary change is natural selection.(Evolution and Natural Selection, Global Change, University of Michigan)Natural SelectionThe thought of Natural Selection according to Darwin is the mechanism fo r evolutionary change. He discussed Natural Selection in the context of an organism struggle for existence. Every organism Darwin believed tended to produce removed more offspring than can actually survive. Limited resources often caused several of these to perish. As a result, there was intense competition between these organisms and only few survive to live and reproduce further. Darwin also believed that the population within a species remained more or less constant over time. However these species do show a wide variation in features and these variations are passed on from one generation to another. (Ridley, 2003). The following chart describes the process of Natural selection.Source Evolution and Natural Selection, Global Change, University of MichiganFor natural selection to occur, reproduction is a very important aspect. Offsprings inherit certain important features from their parents, which help them in the struggle for existence. withal there are 2 essential requirement, namelya. heritable variation of some trait like the beak or skin colour The differences in these traits could b a result of environmental factors and could often be significant for survival in that environment.differential survival and reproduction of that trait is essential to visualize that (Evolution and Na