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To: epicure who wrote (90992)	12/10/2004 12:43:38 PM
From: Neocon	Read Replies (1) \| Respond to of 108807

From the Columbia desk encyclopedia, Sixth edition, 2001: The science of genetics, originating at the beginning of the 20th cent. with the recognition of the importance of the earlier work of Mendel, provided a satisfactory explanation for the origin and transmission of variation. In 1901, De Vries presented his theory that mutation, or suddenly appearing and well-defined inheritable variation (as opposed to the slight, cumulative changes stressed by Darwin), is a force in the origin and evolution of species. Mutation in genes is now accepted by most biologists as a fundamental concept in evolutionary theory. The gene is the carrier of heredity and determines the attributes of the individual; thus changes in the genes can be transmitted to the offspring and produce new or altered attributes in the new individual. 7 Still prevalent misunderstandings of evolution are the beliefs that an animal or plant changes in order to better adapt to its environment—for example, that it develops an eye for the purpose of seeing—and that actual physical competition among individuals is required. Since mutation is a random process, changes can be either useful, unfavorable, or neutral to the individual’s or species’ survival. However, a new characteristic that is not detrimental may sometimes better enable the organism to survive or leave offspring in its environment, especially if that environment is changing, or to penetrate a new environment—such as the development of a lunglike structure that enables an aquatic animal to survive on land (see lungfish), where there may be more food and fewer predators. 8 bartleby.com

To: epicure who wrote (90992)	12/10/2004 12:52:25 PM
From: Neocon	Read Replies (1) \| Respond to of 108807

During the first part of this century the incorporation of genetics and population biology into studies of evolution led to a Neo-Darwinian theory of evolution that recognized the importance of mutation and variation within a population. Natural selection then became a process that altered the frequency of genes in a population and this defined evolution. This point of view held sway for many decades but more recently the classic Neo-Darwinian view has been replaced by a new concept which includes several other mechanisms in addition to natural selection. Current ideas on evolution are usually referred to as the Modern Synthesis which is described by Futuyma; "The major tenets of the evolutionary synthesis, then, were that populations contain genetic variation that arises by random (ie. not adaptively directed) mutation and recombination; that populations evolve by changes in gene frequency brought about by random genetic drift, gene flow, and especially natural selection; that most adaptive genetic variants have individually slight phenotypic effects so that phenotypic changes are gradual (although some alleles with discrete effects may be advantageous, as in certain color polymorphisms); that diversification comes about by speciation, which normally entails the gradual evolution of reproductive isolation among populations; and that these processes, continued for sufficiently long, give rise to changes of such great magnitude as to warrant the designation of higher taxonomic levels (genera, families, and so forth)." - Futuyma, D.J. in Evolutionary Biology, Sinauer Associates, 1986; p.12 talkorigins.org