Wednesday, August 7, 2019

Evolution And Extinction Essay Example for Free

Evolution And Extinction Essay Evolution describes the progressive stages by which organisms existing today have emerged through processes of specialization, adaption and natural selection, from their pre-existing ancestors; it is the significant change in the traits of a population over several generations. On the other hand, extinction of a species of organism is the total disappearance of such forms of life from the surface of the earth due to inability to adapt. Â  The concept of f extinction and fossil development are closely interwoven. It is so important to the support of evolution that Charles Darwin expects that the ‘missing fossils’ would one day emerge as the ‘strongest support’ for the theory he propounded; the theory of evolution by natural selection. The point is that without extinction, there would be no fossils. In the absence of fossils, it readily becomes difficult to relate species ancestor to the existing organisms for the purpose of establishing an unequivocal evolutionary link. Evolution has generated a lot of controversy in contemporary times as it attempts to remove the Creationist theory from its vantage and highly exalted position. It is a thoughtful concept on the origin of living organism that has been supported by Developmental similarities [ascribed to the work of Ernest Haeckel], chromosomal similarities among mammals and primates [e.g. man and chimpanzee], fossil records, biochemical and anatomical similarities such as vestigial organs. Of these, fossil records are the most important since they create the needed link to substantiate evolution. Before reaching forth to connect and disconnect evolution and extinction, it is essential to note that: In the beginning, life was simple and over time, complexities came into view. As a result organisms perpetually attempt to become better suited to the prevailing environmental conditions and demands. Organisms who can effectively develop appropriate features survive i.e. they adapt and those who can not, die. This is the concept of ‘the survival of the fittest’. The newly evolved organism with better adaptation mechanisms produce offsprings much better suited by transfer of such positive and inheritable characters encoded in genes. When conditions change again, evolution occurs for the sustenance of life. Those who do not cope, die and their species progressively disappear. It is this cycle of evolution and extinction that is acclaimed to have maintained living organisms on the Earth. EVOLUTION VERSUS EXTINCTION From the aforementioned facts, it is clear that the two concepts are in a way, mutually interdependent. The progressive emergence of present-day horse from its evolutionary ancestors has been confirmed by fossil discovery and analysis. Same applies to man’s appearance as Homo sapiens. Â  In the examples, the ancestral species have gone into extinction. Their fossils were however discovered. A detailed analysis of these fossils, placing them side by side has made it possible to trace the evolution of horses and man; for man, from extinct Homo habilis through H. erectus to the present day Homo sapiens. This complementation has been achieved thus: detailed study and analysis of the different aspects of the fossil [anatomical, biochemical, and sometimes pathological], and comparing of findings to same properties of existing species has led to the conclusion that speciation and specialization occurred, necessitated by the need for survival. In contrast, if extinction points to the fact that evolution has possibly occurred, what about the ‘missing links’. This is an area that has made the belief in evolution a rather Herculean adventure. If organisms are claimed to have evolved over time, then, there has to fossils for the proposed ancestors. This is particularly important in the case of links i.e. species that combined the properties of two related members of a genus. If these links are absent, evolution raises more questions than it can answer. In this vein, one may look at Extinction as a natural solution to the problems of congestion. It appears to relieve the ecosystem of the burden of many lives. Imagine the congestion and its concomitant intense competition for space that would have resulted if extinction did not occur. The earth would have been in serious turmoil and life would intolerable. On the other hand, evolution shows the capacity that nature has to become suited to sustain life. It evidently relates a potent idea: nature is self-sustaining. It can adapt to changes effectively, and produce same or better results from prevailing conditions.

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