The History of Evolution - Research Paper Example

The History of Evolution Abstract The study of the evolution of man is encapsulated within different scientific disciplines such as Primatology, physical anthropology, linguistics and of course genetics. In the context of the evolution of man the term “human” refers to the genus ‘Homo’. ‘Anthropogenesis’ or what is better known as human evolution is directly connected to the homo – sapiens species which is a greatly researched subject of scientific inquiry. Evolution is the process by which things change into a different and generally more complex form. In the context of living beings, it can be said to be the process by which an organism becomes more refined over a period of time in response to the environment in which it lives. Introduction From time immemorial, man has sought to understand how life forms evolved, and this quest to understand the mystery of evolution has led to the formulation of a number of philosophies and scientific explanations, seeking to unravel the process of creation and evolution. The theory of evolution has been propounded variously by different individuals in different ages and in accordance with the scientific, theological and philosophical beliefs prevalent in the age. From the ancient Greeks to the Renaissance to the Victorian times and in the Modern age, the evolution of this theory itself has been remarkable. Other Evolution Theorists The work of Charles Darwin is considered the final word in the theory of evolution, but two millennia before him, the ancient Greeks had pondered over the same problem. Anaximander (c. 610–546 BC) placed the development of life in the sea, from where these organisms gradually moved to land, while Empedocles (c. 490–430 BC) also theorized that living things did not originate from a supernatural force. (Campbell, Gordon “Empedocles”). They were said to have “survived, being accidentally compounded in a suitable way” according to Aristotle's exposition on Empedocles. (Phys. B8, 198b29 in Kirk, et. al., 304). Aristotle’s theory of evolution was based on studies around the isle of Lesbos. He emphasized order and purpose and used teleology, to explain evolution. He was a vitalist, and to him, the soul was the final cause for all beings and in his ‘Parts of Animals’ he says, "now it may be that the form of any living creature is soul, or some part of soul, or something that involves soul" (641a, 18). He classified organisms in accordance with their complexity of structure and function, or the “ladder of life” (Johnston, Ian, 1999) In the Middle Ages, Greek classical learning was preserved by the Islamists and from here Christian thinkers, like Abelard and Aquinas brought together the theories of Aristotle and Plato and used it to further the cause of natural theology. According to this theory, living things evolved in succession because natura non facit saltum ("nature does not make leaps"). René Descartes proposed a mechanical philosophy wherein it was propounded that the universe and all the life forms on earth had come about mechanically, although some others like Leibniz and Herder still believed in a spiritual force as the cause behind evolution. (Schelling, 1800) The discovery of time in the 18th century saw another shift in the theory of evolution. The concept of a static world was changed when Buffon opened the doors of geological history, with a stage wise plan of development. This led to the science of paleontology and a reworking of geology, but the deists still insisted that the world was the creation of God, guided by a set of laws which maintained its perfection. (Mayr, 57) Buffon was one of the naturalists and in his works ‘Natural History’ and The ‘Epochs of Nature’ we have a well delineated theory which explains evolution as a materialistic event. (Bowler 2003 pp. 75–80, Larson 2004 pp. 14–15)) He believed that the species were well marked varieties that had changed considerably from their original form due to the forces of environment. Georges Cuvier, called the ‘Father of Paleontology,’ used his comparison of fossils of elephants with their living counterparts to demonstrate that the mammoths which lived in an earlier period were a distinct species and he brought in the concept of ‘catastrophism’ to explain why certain species were now extinct. He also proposed the theory of faunal succession to confirm evolutionary patterns. Charles Darwin, the most celebrated scientist of his time started out as an amateur botanist but his inquisitive nature led to the deciphering of the mystery of evolution, with its pioneering studies of creatures both living and extinct. Charles Darwin was greatly influenced by the work of the thinkers who had preceded him and had assisted Robert Grant, a British anatomist, who was influenced by Lamark. He joined him in his study of the life cycle of marine animals. T.R. Malthus' Essay on Population where the equilibrium theory was demonstrated was one of the chief inspirations for Darwin's belief in the theory of natural selection as the reason for the evolutionary process. The equilibrium theory posits that the growth of population, unless checked by disease, famine or voluntary desire will soon outstrip the limited food supply, and lead to a struggle for survival. He applied this theory to plants and animals and soon the theory of natural selection began to take shape. He was also influenced by the natural system of classification, as developed by Augustin de Candolle, which lays emphasis on the struggle between species. (Darwin1861) Darwin's interest in evolution was further aroused when he went on a voyage to the Galapagos Islands, where he saw various species of finches, and believed the variation in their beaks was the result of "adaptation to the environment". What made Darwin's theory acceptable is his rational end, where the mechanical process is engaged and the teleological principles are discarded. Darwin's stint as a naturalist on the H.M.S. Beagle brought about a change in his way of thinking about evolution. His early beliefs were based on the philosophy of naturalism, that species were created according to their environment, and that nature had an innate harmony. But the five-year trip changed his outlook and he began to believe in transmutation, or the idea that species are descendants of earlier species and their characteristics are inherited and he wrote to Hooker that “ …species are not… immutable” (Burrow, 32). With the publication of his most important work “On the Origin of Species” Darwin presented to the world the first complete theory which gave credit to evolutionary change and this was called the theory of natural selection. (Larson2004 pp139-140) Darwin's theory is accepted universally because, in the words of Peter J. Bowler "Through a combination of bold theorizing and comprehensive evaluation, Darwin came up with a concept of evolution that was unique for the time." Understanding the past Recently scientists have carried out studies for the ‘recent African origin’ (RAO) modern humans and have come up with certain facts to prove that the evolution of Homo-sapiens took place in Africa and gradually spread across the globe, while replacing the H. erectus and H. neanderthalensis. On the other hand, the scientists who support an alternative hypothesis of the multi regional origin of modern humans (MTO) hold a different opinion. According to them the modern human species have evolved from an already existing population of Homo- sapiens, especially the H. erectus. ‘The fossil evidence is insufficient to resolve this vigorous debate.’ Leakey, Richard (1994) We have come a long way in understanding Darwin’s theory of the evolution of man and the theories of great evolutionists before Darwin and this knowledge of our past has helped us not only to understand our present but also throws light on our future. Jared Diamond the author of the book “The Third Chimpanzee” together with other anthropologists called this shift of evolution as the “Great Leap Forward.” Evolution has taught us man’s gradual change from uncivilized individuals of the ape age to the most sophisticated to modern age. The different ages such as the Stone Age, Metal age etc. has shown man’s perseverance and the will to progress which has contributed to making him the civilized person he is today. Right from the time of hunting and killing, making tools and clothes, growing crops, we come to understand how evolution has helped man move forward through great changes of behavior and intelligence. As time passed, man learned to develop very sophisticated hunting techniques, bury their dead “and engaging themselves in cave painting.” Ambrose SH (2001) The gradual shifting of man into the modern age has given him important capabilities such as abstract thinking, planning, innovation and a symbolic cultural behavior involving the worshipping of Gods. From man’s evolution we come to know of how he organized his living space and made use of jewellery in his daily life which brought him closer to civilization. ‘Nevertheless, debate continues as to whether a "revolution" led to modern humans ("the big bang of human consciousness"), or whether the evolution was more gradual.’ Mcbrearty S, Brooks AS (2000). References Ambrose SH (2001). "Paleolithic technology and human evolution". Science 291 (5509): 1748–53. Bowler, Peter J. (2003). Evolution: The History of an Idea (3rd edition ed.). University of California Press Burrow, John. Editor introduction to Charles Darwin's Origin of the Species. Penguin Books. England. 1968. Campbell, Gordon. "Empedocles". Internet Encyclopedia of Philosophy. http://www.iep.utm.edu/e/empedocl.htm#H4. Retrieved on 2008-07-15.  Darwin, Charles (1861). On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life (3rd ed.). John Murray, London Johnston, Ian (1999). "Section Three: The Origins of Evolutionary Theory". . . . And Still We Evolve: A Handbook on the History of Modern Science. Liberal Studies Department, Malaspina University College. Kirk, G., Raven, J. and Schofield, M. The Presocratic Philosophers. Cambridge University Press. Cambridge. 1983. Larson, Edward J. (2004). Evolution: The Remarkable History of a Scientific Theory. Modern Library. ISBN 0-679-64288-9 Leakey, Richard (1994). The Origin of Humankind. Science Masters Series. New York, NY: Basic Books. pp. 87–89. Mayr, E. Toward a New Philosophy of Biology. Harvard University Press. 1988. Mcbrearty S, Brooks AS (2000). "The revolution that wasn't: a new interpretation of the origin of modern human behavior". J. Hum. Evol. 39 (5): 453–563. Schelling, System of Transcendental Idealism, 1800 Read More