Lorok said:
Micro evolution, the yeast has never changed species.
This is a false distinction that creationists invented. There is no such thing as "species". It is an abstract, human-invented category, and unfortunately, it is faulty. There is no universally accepted definition of what a 'species' actually is, and any definition has serious flaws. There are no species. There are just organisms living, breeding, and dying, and they don't care whether humans have an easy time of classifying them or not. This is called the "species problem".
The only way you could infallibly categorise organisms together like that would be based on the distance to a common ancestor, (short distance --> closely related, long distance --> distantly related), but unfortunately, we just don't have anywhere near the data available to actually do that. I don't even know how far back my common ancestor with -you- is, and that's only a couple thousand years at most. The fossil record is better than creationists say but it's not even remotely good enough to do taxonomy.