Evidence of evolution
Evidence of evolution consists of all historical and modern facts which suggest the validity of microevolution. There is no physical evidence for macroevolution which is also referred to as the general theory of evolution. The two aspects of macroevolution which must be proven are: first, that the various species of life have appeared gradually over the course of time (i.e., hundreds of millions of years) by natural means (see theory of evolution by natural selection); second, that all forms of life have a common ancestor (see common descent).
Creationism, particularly the religious idea generally called Young Earth Creationism, rejects these aspects of evolution on Biblical grounds. Just over half of creationists agree with the first aspect of evolution (gradual appearance); see Old Earth Creationism. Other creationists approach the problem with the faith that God created every important form of life as it exists today. It is important to note that the theory of evolution says nothing about how the first life form(s) originated.
The majority of physical scientists, who often hold an atheistic worldview and/or insist on employing methodological naturalism, however, have currently accepted the two aspects of evolution mentioned above since at least the 20th century. It has been alleged that these scientists insist on the validity of macroevolution on philosophical/religious grounds and not due to the actual evidence that they have found.
Mainstream geologists and biologists believe that fossils show the body plans of dead animals and plants, and that these can be assign ages ranging from hundreds of thousands to hundreds of millions of years (see carbon dating). This evidence is disputed by Scientific Creationism because they hold to the premise that the Earth is less than 10,000 years old, and thus they question the validity of the physical evidence.