Evolution refers to the process of the collection of genes in variety and in frequency changing from one generation to another by reason of selective factors (i.e. natural selection, artificial selection, sexual selection, etc.). Some misinterpret this to mean that one species always becomes a new species which may happen but generally, the changes that happen are slight and go unnoticed. Overtime though, a timeline of fossils reveals very interesting trends like humans possibly developing a straighter posture. In short, fossils can demonstrate new species forming from old ones, adaptations in response to the environment, or what have you.
That selection was natural.
natural
Darwin was the first scientist to have the courage to put forward the theory of natural selection.
Natural selection.
That is Darwin's principal of Natural Selection, sometimes called survival of the fittest.
Natural Selection
Natural Selection
Natural Selection
Natural Selection
That selection was natural.
Natural selection
natural
Natural Selection
Darwin
Darwin was the first scientist to have the courage to put forward the theory of natural selection.
Evolution by natural selection.
Charles Darwin used Natural Selection to answer the survival of the fittest.