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The argument between creation and evolution has been raging for years and years. Although evolution does not rule out the theory of intelligent design, some people still consider the theory of evolution to be false. But science proves evolution to be true via natural selection and other mechanisms.
Natural Selection is the heart and soul of the theory of evolution. Natural Selection is the process by which genetic mutations that enhance reproduction become, and remain, more common in successive generations of a population1. Natural Selection is possible because of three different facts. (1) Heritable variation exists within populations of organisms, (2) Organisms produce more offspring than can survive, and (3) These offspring vary in their ability to survive and reproduce. These facts produce competition between organisms for survival and reproduction. Consequently, organisms with traits that give them an advantage over their competitors pass these traits on, while traits that do not give the organism an advantage are not passed on to the next generation. The central concept of natural selection is the evolutionary fitness of an organism. This measures the organism's genetic contribution to the next generation. However, this is not the same as the total number of offspring; instead fitness measures the proportion of upcoming generations that carry an organism's genes. Consequently, if an allele increases fitness more than the other alleles of that gene, then with each generation this allele will become more common within the population. These traits are said to be "selected for". Examples of traits that can increase fitness are enhanced survival, and increased ability to reproduce. On the other hand, the lower fitness caused by having a less beneficial allele results in this allele becoming rarer, meaning that they are "selected against". The fitness of an allele is not a fixed characteristic, if the environment changes, previously neutral or...