1 definition by Robert Gay - Biologist

The idea that organisms change over time, and that is change occurs through natural selection which allows favorable traits to be passed along through generations. It has been refered to as a theory, which, in science, means it is an idea that has not been disproven. Many scientists are moving towards calling it the Law of Evolution, similar to the Law of Gravity, in order to help reduce frivolous claims that it is "only a theory" by people ignorant of what a scientific theory entails.
Some (especially miseducated critics) refer to macro and microevolution. There is no such thing. Evolution is evolution. Fruit flys, rats, frogs, etc., have all been observed undergoing character change in laboritories, resulting in the inability to mate with other members of the base species (the control), thus forming a new species. Several examples of so-called macroevolution (the change at a genus level) have been observed by biologists in the rain forest. Furthermore, good fossil evidence shows transition between genera, and even higher taxanomic orders (incorrectly called Kingdom, Phylum, etc. - current work in phylogentic taxonomy does away with Linnean ranks). Representatives of higher order change in the fossil record includes change with fish, fish to amphibians, with amphibians, within reptiles, "reptiles" to dinosaurs, within dinosaurs, dinosaurs to "birds", within "birds", "reptiles" to mammals, within mammals, and other mammals to humans. I am not mentioning invertebrates here, as I do not deal with them in my line of work. See current molecular and physical phylogenetic phylogenies in Nature, Science, Journal of Vertebrate Paleontology, etc., all of which are peer reviewed, something most parties who oppose evolution will not do (publish in peer-reviewed journals).
Evolution has nothing to do with The Big Bang - that is astronomy, not biology.
The synthysis and subsequent radiation and adaptation of life is a wonderful and beautiful thing, and far more complex than the, "We don't look like fish, so can't have evolved," argument presented by many whom view evolution/natural selection as the work of the devil.
A good example of evolution is the fossil record showing the transition between fish and amphibians, or dinosaurs and birds.
by Robert Gay - Biologist December 5, 2003
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