Evolution is the process of change in an organism that occurs over a long period of time.
How does evolution really work? Actually, not how some of our common evolutionary metaphors would have us believe. For instance, it's species, not individual organisms, that adapt to produce evolution, and genes don't "want" to be passed on -- a gene can't want anything at all! Alex Gendler sets the record straight on the finer points of evolution.
Although most people realize that there isn’t a conscious entity controlling evolution, they nevertheless think that natural selection provides organisms with the traits that they need.