So, here's the story.
You have a creature, say.. A frog.
The frog is stupid, a simple creature at the moment.
When it mates, it has babies. But, to mate, it must first be accepted by the female. This is where one of the most important parts of evolution is; genetics. From the earliest ancestor of this frog, the females had to accept the males, so, what better way to decide than abilities? This is another key point. Abilities.
Think of it like this:
You have to survive out in the wild. If you're weak, you'll get no food, and either will die or get no mate, or both. Because the weak ones die out, the best genes are passed on. What genes get passed on can either weaken the next generation or help the next generation. In most cases this will end up helping the next generation wether or not the next genes are weak. This process will repeat itself through thousands upon thousands of years, until you have a stronger species, or a whole new species.
Species can change due to mutation or "natural selection" which is what I just explained. Mutation would be like a creature, lets say, still a frog, which grows more muscle than the rest normally would. Mutation can either hinder a species, help a species, or do none of the above. Let's say said frog, a stronger frog, eats more, and grows more. The females will mate with that frog more than other frogs, and thus the offspring have a higher chance of inherriting said gene, of more muscle. This is basically how a species evolves through mutation and/or "natural selection."
To sum it up:
Natural selection - a change in genetics that is "naturally" accepted by others of the species, thus passing on the genes from the accepted ones into a new generation, over time creating a new species.
Evolution - The changing of a species, and possibly making a new species, over time due to natural selection.
Mutation - Difference in DNA in a creature of a species
That's what I understand of Evolution. Correct me if I'm wrong.
Discuss.
Oh, and, just for the record, I have never taken any "classes" on Evolution. It is a subject I have pondered throughout the many hours of the many days of the many months in the many years of my life. This is my theory, which, personally I believe to make sense.
