Darwin and Evolution Assignment Example | Topics and Well Written Essays - 750 words

Darwin and Evolution - subsidization ExamplePrior to Darwin, though some naturalists had speculated about modification of species, they failed to explain why and how species change. They to a fault believed that organic evolution began with the special creation of but a fixed number of species. Partly influenced by Thomas Malthus judge on the Principle of Population and stimulated by a letter from Alfred Russel W all in allace, in 1859 Charles Darwin discussed in stop the evolution of species by means of natural selection in his famous work titled On the melodic line of Species, which totally revolutionized the previous concepts of evolutionary biology. Natural selection refers to a process in which species compete and vie for their survival according to the limited resources and conditions of their natural environment with diametrical adaptive abilities. As individuals in a population are not same due to difference in inherited propertys, nature only selects those individu als that are best suited to the environmental conditions, and thus rest of the population dies oer time. As all the offspring in a population acquire characteristics from their ancestors, produced more than nature can support and restrain distinct reproductive characteristics, only those organisms will survive that are better adapted to the living conditions. This mode that organisms with higher reproduction ability will remain due to higher probability of their descendants to survive, and different will eventually become extinct due to less survival rate of their offspring with the personation of time. Since environmental conditions are different from place to place, there will be variation in characteristics of species at different locations. Darwin concluded that populations extending over large areas or through migration might have been isolated resulting in variation of their characteristics according to varying environments. Over long periods of time, they may have diverg ed or evolved into separate species different from for each one other. For instance, Darwin found that finches he observed on the Galapagos Islands were similar to one another than they were to finches of the mainland. He also noticed that some varieties were only existent on the archipelago islands. So, he proposed that all species might have descended from a common ancestor and increase in number of species occurred through evolutionary natural selection over time rather than special creation. Question Two Darwin and other naturalists believed that variations among individuals of a species were due to mixing of traits from two male and the female. He was not aware of the heredity mechanism and different traits were regarded to be the result of intermingle of characteristics through generations over time. However, the concept of blending inheritance failed to describe the survival of variety as they descended through generations with time. It also failed to describe the maintena nce of specific characteristics in varieties and that how new species would emerge through blending. It was 1866, when Gregor Mendel published his experimental findings on garden peas. To experiment with pure seeds, he selected a self pollinating plant. He experimented with garden peas that were different from each other in many characteristics such as their flowers were either red or white, had fleeceable or yellow seeds, and tall or dwarf. After cross-breeding generations having different characteristics, he observed that descendants from each cross possessed characteristics of only one of the parents and blending did not happen. Mendel concluded that instead of blending of sealed fluids, heredity from parents was passed on to offspring through independent discrete units, particles or factoren, which were later termed as genes. The characteristic that appeared in a descendant after cross breeding was termed