Charles Darwin – Report
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Science and Technology 13.3.2014. Presentation Charles Darwin – Report - Biography Charles Robert Darwin was an English naturalist and geologist, born on the 12 of February 1809 in Shrewsbury, Shropshire, and was best known for his Theory of evolution. He worked on this theory for 20 years. He established that all species of life have descended over time from common ancestors, and that this branching pattern of evolution resulted from a process that he called natural selection. He was the grandson of the scientist Erasmus Darwin. His mother died when he was eight years old, and he was brought up by his sister. He was sent to Christ's College in Edinburgh to study medicine, which he hated, and a final attempt at educating him was made by sending him to Cambridge, to study theology (1827). During that period he loved to collect plants, insects, and geological specimens. John Stevens Henslow, his botany professor who encouraged him in his scientific research was the one who secured a place for Darwin as a naturalist on the surveying expedition of HMS Beagle to Patagonia (1831-1836). On December 27, 1831, the HMS Beagle launched its voyage around the world with Darwin. Throughout the trip, Darwin collected a variety of natural specimens, including birds, plants and fossils. Through hands-on research and experimentation, he had the unique opportunity to closely observe principles of botany, geology and zoology. The Pacific Islands and Galapagos Archipelago were of particular interest to Darwin, as was South America. On the voyage, Darwin read Lyell's 'Principles of Geology' which suggested that the fossils found in rocks were actually evidence of animals that had lived many thousands or millions of years ago. He became friends with Sir Charles Lyell, became secretary of the Geological Society (1838- 1841), and in 1839 married his cousin Emma Wedgwood (1808-1896). He devoted himself to science, in spite of continuous ill-health; He had suffered from Chagas's disease, which he had contracted from an insect bite while in South America. At Down House he devoted himself to the great work of his life—the problem of the origin of species. In 1842 and 1844 he wrote short notes and conclusions which embodied the principle of natural selection, the essence of Darwinian Theory. However, he delayed publication of his hypothesis. However, in 1858 Alfred Russel Wallace sent him a memoir of the Malay Archipelago, which, to Darwin's surprise, contained in essence the main idea of his own theory of natural selection. Darwin published On the Origin of Species by Means of Natural Selection, in 1859. Even though the whole of Europe was deeply interested in it, it immediately began to be criticized because it contrasted the implications of the Book of Genesis, or the Bible. Other Darwin's significant works were: The Fertilisation of Orchids (1862), The Variation of Plants and Animals under Domestication (1867), and The Descent of Man, which provoked controversy by saying that the human race derived from a hairy animal belonging to the great anthropoid group, such as the orang-utan, chimpanzee, and gorilla. In his 1871 work Selection in Relation to Sex he also developed his important supplementary theory of sexual selection. Later works include The Expression of Emotions in Man and Animals (1872), Insectivorous Plants (1875), The Effects of Cross and Self Fertilisation in the Vegetable Kingdom (1876), Different Forms of Flowers in Plants of the Same Species (1877), and The Formation of Vegetable Mould through the Action of Worms (1881). - Darwin's Theory of Evolution The theory of evolution is one of the great intellectual revolutions of human history, drastically changing our perception of the world and of our place in it. Charles Darwin put forth a coherent theory of evolution and amassed a great body of evidence in support of this theory. In Darwin's time, most scientists fully believed that each organism and each adaptation was the work of the creator. Linneaus established the system of biological classification that we use today, and did so in the spirit of cataloguing God's creations. In other words, all of the similarities and dissimilarities among groups of organisms that are the result of the branching process creating the great tree of life. Darwin was influenced by observations made during his youthful voyage as naturalist on the survey ship Beagle. Especially important was his 5 weeks long visit to the Galápagos Islands in the Eastern Pacific Ocean. It was there that he made the observations that eventually led him to comprehend what causes plants and animals to evolve, but he apparently did not clearly formulate his views on this until 1837. At the time he left the Galápagos Islands, he apparently still believed in a traditional Biblical creation of all life forms.The Galápagos Islands have species found in no other part of the world, though similar ones exist on the west coast of South America. Darwin was struck by the fact that the birds were slightly different from one island to another. He realized that the key to why this difference existed was connected with the fact that the various species live in different kinds of environments.He also observed a whole array of unique finches, the famous "Darwin's finches," that exhibited slight differences from island to island. In addition, they all appeared to resemble, but differ from, the common finch on the mainland of Ecuador, 600 miles to the east. Patterns in the distribution and similarity of organisms had an important influence of Darwin's thinking. Darwin’s theory of evolution entails the following fundamental ideas. The first three ideas were already under discussion among earlier and contemporaneous naturalists working on the “species problem” as Darwin began his research. Darwin’s original contributions were the mechanism of natural selection and copious amounts of evidence for evolutionary change from many sources. He also provided thoughtful explanations of the consequences of evolution for our understanding of the history of life and modern biological diversity. 1. Species (populations of interbreeding organisms) change over time and space. The representatives of species living today differ from those that lived in the recent past, and populations in different geographic regions today differ slightly in form or behavior. These differences extend into the fossil record, which provides ample support for this claim. 2. All organisms share common ancestors with other organisms. Over time, populations may divide into different species, which share a common ancestral population. Far enough back in time, any pair of organisms shares a common ancestor. For example, humans shared a common ancestor with chimpanzees about eight million years ago, with whales about 60 million years ago, and with kangaroos over 100 million years ago. Shared ancestry explains the similarities of organisms that are classified together: their similarities reflect the inheritance of traits from a common ancestor. 3. Evolutionary change is gradual and slow in Darwin’s view. This claim was supported by the long episodes of gradual change in organisms in the fossil record and the fact that no naturalist had observed the sudden appearance of a new species in Darwin’s time. From one generation to the next, the struggle for resources (what Darwin called the “struggle for existence”) will favour individuals with some variations over others and thereby change the frequency of traits within the population. This process is natural selection. The traits that confer an advantage to those individuals who leave more offspring are called adaptations. Darwin’s process of natural selection has four components. 1. Variation. Organisms (within populations) exhibit individual variation in appearance and behavior. These variations may involve body size, hair color, facial markings, voice properties, or number of offspring. On the other hand, some traits show little to no variation among individuals—for example, number of eyes in vertebrates. 2. Inheritance. Some traits are consistently passed on from parent to offspring. Such traits are heritable, whereas other traits are strongly influenced by environmental conditions and show weak heritability. 3. High rate of population growth. Most populations have more offspring each year than local resources can support leading to a struggle for resources. Each generation experiences substantial mortality. 4. Differential survival and reproduction. Individuals possessing traits well suited for the struggle for local resources will contribute more offspring to the next generation. - Contributions Many people consider him even the most important person in our history. He made the foundations of a theory how human kind evolved and survival of the fittest. Although he was controversial for many religious institutions and their followers, his theories remained almost unchanged from the 19th century until now. He gave many answers on questions about existence of all living things, from a bacteria to a human being. He also contributed to secularisation, the separation of religious institution's from state institutions, that had a lot of influence on them and the even law itself. Darwin was the first one who introduced biological evolution trough biological selection. He excluded God from human evolution and claimed that humans most probably evolved from primates but it's interesting that he never actually claimed that God doesn't exist. At that time there was a general theory that claimed that species are exactly how God created them and that no matter how the environment changes they stay the same; that was also known as essentialism. Through his theory of evolution Darwin drifted away from essentialism, but besides that, Darwin presented a completely new view of revolutionary thinking called population thinking. That way of thinking emphasizes the uniqueness of every individual and he supported that with evidence, facts and descriptions, so many scientists believe that this was Darwin’s main contribution to science.