Adaptation, not evolution. If evolution were true, it would mean everything on this earth was started by one thing. And if that were true there would only be one living thing on earth. How would it make sense for a fish to grow legs, when there are no advantages for this? It would be mutation after mutation that wouldn't benefit the original animal. It would benefit humans to have four arms, it doesn't mean we are going to evolve to have four arms. Evolution makes no sense.
I just have had another epiphany moment with you guys that think evolution is wrong. Well at least Fish and Sativa.
You guys think that evolution means that one animal literally turns into another animal!
Like we are saying that chimps turned into humans.
Here is a direct example of extra extremeties:
http://en.wikipedia.org/wiki/Polydactyly
Now lets say that those fingers worked very well, and somehow that kid has some kids. Those kids would have that trait (there is whole villages that have a high number of things like this). After a few generations two people that have this resessive trait get together, not knowing that they are distant relatives and have a baby, and there it is again.
Because this is (hypothetically) a desired trait, they mate, and on it goes until you have a section of the planet that have 6 digits.
As this goes on more and more, it could take over the whole population so that everyone has kids.
Or it could be regionalized. So that eventually that group of people are no longer considered homo sapiens. They are now homo sapisixians. And you now have two groups of people.
Btw this is very similar to how dwarfism occur.