Natural selection
Its role in Evolution is expressed vaguely. How does natural selection "help" bring a new species into existence? Merely by weeding out the "mistakes"?. (Discuss)
Natural selection is a principle that was proposed by Charles Darwin and Alfred Russel Wallace, who noted that organisms which were better adapted to their environment tended to survive longer and reproduce more than less well-adapted organisms.
These organisms have to be able to survive long enough to reproduce, and produce viable offspring capable of the same, in order to ensure the continuing survival of their genetic traits. They do not have to be perfectly adapted to their environment; they only have to be able to survive in it.
Furthermore, an organism may be well adapted to one environment but not be able to survive in another, therefore there is no such thing as a perfect organism.
Natural selection is not mutation. It does not make anything new, alter anything, etc... Natural selection can cause extinction based on survival of the fittest, but the processes of creation and mutation lie outside the scope of natural selection. Natural selection simply "selects" from what is available at that specific moment.