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| | As evolution can produce highly optimized processes and networks, it has many applications in [[computer science]]. Here, simulations of evolution using [[evolutionary algorithm]]s and [[artificial life]] started with the work of Nils Aall Barricelli in the 1960s, and was extended by [[Alex Fraser (scientist)|Alex Fraser]], who published a series of papers on simulation of [[artificial selection]]. [[Artificial evolution]] became a widely recognized optimization method as a result of the work of [[Ingo Rechenberg]] in the 1960s and early 1970s, who used [[evolution strategies]] to solve complex engineering problems. [[Genetic algorithms]] in particular became popular through the writing of [[John Henry Holland|John Holland]]. Adaptation in Natural and Artificial Systems, University of Michigan Press, ISBN 0262581116 As academic interest grew, dramatic increases in the power of computers allowed practical applications. Evolution algorithms are now used to solve multi-dimensional problems more quickly than software produced by human designers, and also to optimize the design of systems. | | As evolution can produce highly optimized processes and networks, it has many applications in [[computer science]]. Here, simulations of evolution using [[evolutionary algorithm]]s and [[artificial life]] started with the work of Nils Aall Barricelli in the 1960s, and was extended by [[Alex Fraser (scientist)|Alex Fraser]], who published a series of papers on simulation of [[artificial selection]]. [[Artificial evolution]] became a widely recognized optimization method as a result of the work of [[Ingo Rechenberg]] in the 1960s and early 1970s, who used [[evolution strategies]] to solve complex engineering problems. [[Genetic algorithms]] in particular became popular through the writing of [[John Henry Holland|John Holland]]. Adaptation in Natural and Artificial Systems, University of Michigan Press, ISBN 0262581116 As academic interest grew, dramatic increases in the power of computers allowed practical applications. Evolution algorithms are now used to solve multi-dimensional problems more quickly than software produced by human designers, and also to optimize the design of systems. |
| − | ===Michael Ruse===
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| − | There is a common belief that evolution and religion, Darwinian evolution and Christianity especially, are world pictures that are forever opposed. This is a belief today endorsed and promulgated both by extreme evangelical Christians (who support some version of Biblical literalism) and ardent ultra-Dawinians (who hold that their theory necessarily falls into an atheistic mode of thinking). Traditionally, however, this opposition has not been universally accepted. Many people find that there is much in common between the two systems and, thus, great opportunities for sympathetic dialogue. Much of the difficulty and debate arises from ignorance about the various positionsPage 280 | Top of Article involved. This is especially true of evolution. In discussing the idea of selection, it is convenient to make a three-fold distinction between the fact of evolution, the path of evolution, and the theory or mechanism of evolution.
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| − | ====The fact of evolution====
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| − | The fact of evolution is simply the idea that all organisms, living and dead, came into being by a long developmental process, governed by natural laws, from organisms of a different, probably much simpler, kind. The fact of evolution includes the belief that the original organisms themselves developed by natural processes from inorganic materials. If one wanted to extend from the biological to the cosmological, one would see the fact of evolution as including all developmental change from the time of the Big Bang.
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| − | Claims for the fact of evolution were first mooted in the seventeenth century with the extension of Newtonian ideas from the mere running of the universe to its supposed development through natural laws. It was later argued—by, among others, Immanuel Kant—that this happened in a regular fashion as suns and planets were formed from gaseous nebulae. Biological evolutionary ideas began to appear towards the end of the eighteenth century. A prominent exponent in England was the physician and naturalist Erasmus Darwin, grandfather of Charles Darwin; in France a little later the chief advocate of the idea was the biologist Jean Baptiste de Lamarck.
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| − | The evidence offered for evolution (then more generally called transmutation) tended to be anecdotal. A major reason why few endorsed the idea with enthusiasm was that it was seen to be a reflection of the ideology of progress—upward change in the human social world, and upward change in the history of life, from "monad" to "man." Critics, like the father of comparative anatomy, the French biologist Georges Cuvier, found the idea religiously offensive less because it clashed with literal interpretations of the Bible than because of its underlying philosophy of progress. Such a world picture, in which humans can make the difference unaided, was at odds with the Christian notion of providence, where all depends on God's grace. Although by the mid nineteenth century religious worries were still much in evidence, Charles Darwin met this challenge head on in the Origin of Species (1859), the groundbreaking work in which he introduced his theory. Darwin was not the first to argue for the fact of evolution, but by marshaling so much evidence from paleontology, embryology, geographical distributions, and more, he made the fact of evolution empirically plausible and no longer reliant on an underlying social philosophy for acceptance.
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| − | The path of evolution
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| − | The path of evolution, or phylogeny, is simply the history of the past as given in the fossil record and as can be discerned indirectly from anatomical and embryological causes and, increasingly, molecular evidence. Thanks to various sophisticated methods of dating, researchers can say that the universe itself is (since the Big Bang) about fifteen billion years old, that the Earth is about 4.5 billion years old, and that life first appeared on the planet about 3.75 billion years ago. Complex life began with the Cambrian explosion about six hundred million years ago; the Age of Mammals began about sixty-five million years ago (although the first mammals go back two hundred million years); the first known ancestors of humans are about four million years old (upright but with ape-sized brains); and, depending on how one measures things, the modern human species Homo sapiens is between five hundred thousand and a million years old.
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| − | Traditionally, life is pictured as a tree with contemporary organisms at the ends of the upper branches. However, Lamarck and some other early evolutionists thought that life developed upwards in separate but parallel lines, with variations laid over these. Alternatively, some researcher believe that viruses may carry genes from one line to other, very different, lines, so perhaps a better picture is that of a net. Paradoxically, the main outlines of the history of life were worked out in the first part of the nineteenth century, primarily by those who did not subscribe to evolution, and only later was the process of life given an evolutionary interpretation.
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| − | ====The theory or mechanism of evolution====
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| − | The theory or mechanism of evolution has garnered many hypotheses. Notorious before DarwinPage 281 | Top of Article was Lamarck's idea of the inheritance of acquired characteristics, which had not originated with him; Erasmus Darwin had accepted it, as did Charles Darwin much later. In the Origin of Species, Darwin described the mechanism that is generally accepted as the chief force for change: natural selection. More organisms are born than can survive and reproduce, leading to a struggle for survival and, more importantly, reproduction. Given naturally occurring variation, and the fact that those that survive will tend on average to be different from those that do not, there will be a differential reproduction, natural selection. In time this leads to full-blown evolution, and evolution of a particular kind, for selection produces organisms with adaptations. The eye and the hand come naturally as a result of Darwin's causal process.
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| − | ====Conclusion====
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| − | In the years subsequent to the publication of Darwin's Origin, there have been a multitude of putative alternatives to Darwinian selection, including orthogenesis (a life force driving things), mutationism (major one-step changes), genetic drift (randomness), and molecular drive (DNA has its own built-in ways of change); none has established itself as a full and genuine rival to natural selection. This is not to say that all controversy is therefore quelled. Apart from the question of whether selection can be applied profitably to such issues as the origin of life, there are also questions about the form that life's history will take given selection as the main mechanism of change. Will it be smooth and gradual (phyletic gradualism), as supposed by Darwin and his followers, or will it be jerky and abrupt (punctuated equilibria), as supposed by some leading paleontologists, notably Stephen Jay Gould? Controversy about these issues, however, should not be taken as controversy about other matters. The fact of evolution is firmly established, the main outlines of the path of evolution have been worked out and details are being filled in (for example, that birds are descended from dinosaurs), and selection is taken to be the major mechanism of change even though there are debates about its applicability and its precise results and consequences.
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| − | Evolution as fact, path, and theory is a thriving part of the biological sciences, and it is also seen to have extensions and implications for thinking about many other parts of human experience. Social scientists are increasingly turning to evolutionary ideas to flesh out their understanding of human nature and society; philosophers have (after many hesitations) begun to see how evolution, selection even, can profitably deepen their understandings of epistemology (theory of knowledge) and ethics (theory of morality); novelists and poets use evolutionary themes to illuminate aspects of human understanding and motivation; linguists turn to Darwinism for help in grasping the developments of languages; and so it is in many other subjects and disciplines. Although there is still much opposition to evolutionary ideas on various religious fronts, there is realization by theologians and historians that the old story of the warfare between science and religion was much overblown, and many see evolution as an aid to faith and understanding rather than a hindrance.
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| − | ====Bibliography====
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| − | Bowler, Peter. Evolution: The History of an Idea. Berkeley: University of California Press, 1984.
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| − | Depew, Daniel J., and Weber, Bruce H. Dawinism Evolving. Cambridge, Mass.: MIT Press, 1994.
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| − | Desmond, Adrian, and Moore, James. Darwin: The Life of a Tormented Evolutionist. New York: Warner, 1992.
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| − | Richards, Robert J. The Meaning of Evolution: The Morphological Construction and Ideological Reconstruction of Darwin's Theory. Chicago: University of Chicago Press, 1992.
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| − | Ruse, Michael. Monad to Man: The Concept of Progress in Evolutionary Biology. Cambridge, Mass.: Harvard University Press, 1996.
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| − | Ruse, Michael. The Darwinian Revolution: Science Red in Tooth and Claw, 2nd edition. Chicago: University of Chicago Press, 1999.
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| − | Ruse, Michael. Can a Darwinian be a Christian? The Relationship Between Science and Religion. Cambridge, UK: Cambridge University Press, 2001.
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| − | Ruse, Michael. Darwin and Design: Science, Philosophy, and Religion. Cambridge, Mass.: Harvard University Press, 2003.
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| − | MICHAEL RUSE
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| − | Source Citation: RUSE, MICHAEL. "Evolution." Encyclopedia of Science and Religion. Ed. J. Wentzel Vrede van Huyssteen. Vol. 1. New York: Macmillan Reference USA, 2003. 279-281. 2 vols. Gale Virtual Reference Library. Thomson Gale. Madison County Public. 31 Dec. 2007
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| | ==Further reading== | | ==Further reading== |
In biology, evolution is the change in the inherited traits of a population from generation to generation. These traits are the expression of genes that are copied and passed on to offspring during reproduction. Mutations in these genes can produce new or altered traits, resulting in heritable differences (genetic variation) between organisms. New traits can also come from transfer of genes between populations, as in migration, or between species, in horizontal gene transfer. Evolution occurs when these heritable differences become more common or rare in a population, either non-randomly through natural selection or randomly through genetic drift.
Natural selection is a process that causes heritable traits that are helpful for survival and reproduction to become more common, and harmful traits to become rarer. This occurs because organisms with advantageous traits pass on more copies of these traits to the next generation. The measurement of selection on correlated characters (Evolution, volume 37 Over many generations, adaptations occur through a combination of successive, small, random changes in traits, and natural selection of those variants best-suited for their environment.) [1] , Mechanisms: the processes of evolution
Understanding Evolution, In contrast, genetic drift produces random changes in the frequency of traits in a population. Genetic drift arises from the element of chance involved in which individuals survive and reproduce.
One definition of a species is a group of organisms that can reproduce with one another and produce fertile offspring. However, when a species is separated into populations that are prevented from interbreeding, mutations, genetic drift, and the selection of novel traits cause the accumulation of differences over generations and the emergence of new species. Stephen Gould, The Structure of Evolutionary Theory, Belknap Press, ISBN 0-674-00613-5 . The similarities between organisms suggest that all known species are descended from a common ancestor (or ancestral gene pool) through this process of gradual divergence. {Douglas J. Futuyma, Evolution, Sinauer Associates, Sunderland, Massachusetts, ISBN 0-87893-187-2 )
The theory of evolution by natural selection was first proposed by Charles Darwin and Alfred Russel Wallace and set out in detail in Darwin's 1859 book On the Origin of Species[2]. Related earlier ideas were acknowledged in [3] In the 1930s, Darwinian natural selection was combined with Mendelian inheritance to form the modern evolutionary synthesis, "understanding evolution" in which the connection between the units of evolution (genes) and the mechanism of evolution (natural selection) was made. This powerful explanatory and predictive theory has become the central organizing principle of modern biology, providing a unifying explanation for the diversity of life on Earth. [4] Statement on the Teaching of Evolution, The Interacademy Panel on International Issues, [5] Statement on the Teaching of Evolution, American Association for the Advancement of Science.
Heredity
Inheritance in organisms occurs through discrete traits – particular characteristics of an organism. In humans, for example, eye color is an inherited characteristic, which individuals can inherit from one of their parents. (Sturm RA, Frudakis TN, Eye colour: portals into pigmentation genes and ancestry). Inherited traits are controlled by genes and the complete set of genes within an organism's genome is called its genotype. Genetics: what is a gene? (Nature, v. 441, 2006)
The complete set of observable traits that make up the structure and behavior of an organism is called its phenotype. These traits come from the interaction of its genotype with the environment.Template:Cite journal (Epigenetics and phenotypic variation in mammals, Mamm. Genome
External links
General information
History of evolutionary thought
