Evolution
Darwin used the theory of natural selection to explain the process of evolution.
Evolution is a continuing process of natural selection that leads to the gradual change of an organism over time.
It may result in the formation of a new A type of organism that is the basic unit of classification. Individuals of different species are not able to interbreed successfully..
Fossils
Fossils are the remains of living organisms that have been preserved in rock for millions of years.
They provide evidence for evolution by showing how an organism looked millions of years ago and how it has changed over time.