Evolution by Natural Selection
Charles Darwin put forward the Theory of Evolution by Natural Selection in his book, The Evolution of Species, published in 1859. Following decades of research he put forward the scientific theory that all species have evolved from earlier species, back to the beginning of life on Earth. Genetic mutations occur from time to time, and randomly, in living creatures. Natural selection is what decides whether a mutation will help the species survive in a competitive environment. If, as the result of some change passed down from its parents, an individual is better able to find food, evade predators or attract sexual partners, then that individual is more likely to produce a greater number of offspring, eventually leading to improvement in its gene pool.
There are several forms of creationism, and new variants are constantly put forward, as old variants are discarded. The chief groupings of creationists are known as "Young-Earth creationists" and "Old-Earth creationists".
Young-Earth creationists believe that the Earth is only a few thousand years old, and that all life forms were originally created in much the same form as we see today. Most Young-Earth creationists do accept the reality of 'micro-evolution', evolution within a species, as the evidence of small changes are so obvious for all to see. The principal arguments put forward by Young-Earth creationists are intended to disprove evolution rather than to prove creationism.
Because the scientific evidence for the great age of the Earth has become so overwhelming, some creationists have adopted an "Old-Earth creationism" stance. Most accept that species really have evolved over the eons. They accept the age of the Earth but insist that natural selection is not the reason for evolution. One of the most recent hypotheses put forward by Old-Earth creationists is called Intelligent Design. One variant of this holds that God took part in the evolution of life throughout history, guiding the progress of evolution. Another variant holds that God, in some way, made the rules for evolution at the beginning of the Universe and that those rules inevitably and predictably resulted in life as we know it.
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