How is it that two people can populate the entire species? This also happens again after the Flood. No matter how I look at it, I don't think it can be done.
Actually Umaro that's not entirely accurate, if I can recall there where at least eight people aboard the ark, after the Flood it was eight people, not two.
Second, it's very possible, it's not like Adam and Eve had a kid once the other one matured, and beyond that, reproduction isn't linear, even then, you have to consider that if you do make it linear, it will populate over quite some time.
If Adam and Eve lived 900 years and had two babies every year, well, you can figure out the math in 900 years time:
900 x 2 = 1,800
That's 1,800 people in 900 years time, coming from two single partners, now imagine all of Adam and Eve's children, and eventually, how they reproduced, and being that even those results are based on an assumed constant rate, it's indeed possible for Adam and Eve to have populated the entire earth, even with the Flood.
How did these people (and some mentioned later) live for over 900 years? Not even trees live that long for the most part.
Creationists explain this as having something to do with their DNA, their DNA was so various and complex, but over time it began to lose and essentially deplete, which causes a shorter lifespan as the generations go on, technically not all of the descendants of Adam lived shorter after the other, which is actually why creationism still flourishes (being that not all genes lead to a depletion stage but indeed can "retrieve" some older characterisitics in the process of inheritance.)
Genesis 1:29 I think it is (could be mistaken) also says that before the fall, everything was an herbivore. Why then do carnivore species have the proper teeth?
You'll find in the first few pages in
The Origin of Species that even Darwin explains this, it has to do with enviroment and adaptions, there's a chance it could be all wrong, but hey, who knows, creationism could be just as right as evolution.