Why the hell can you people just not admit that we just do not know because the information is not specifically given?
All of these scenarios are fabricated without a thread of evidence to back them up, so if you really have to pick a fabrication to believe in rather then rely on your faith, at least pick the more plausible one.
The fact is that the Hebrew Bible is based on explaining to Hebrews the relationship between God and Hebrews. It is all about Hebrews!
For all we know, the Adam and Eve story may just well be an attempt at the explanation of how the Hebrew race began and the "other" creation of man is about all of the others.
As much as I hate to state this, I go along more with Royc as far as it is more plausible that the human race, or at least a part of it, is a transplant from another of God's created planets in a galaxy far, far away.
Genesis in no way gives any details that allow us to come up with any practical history of the beginnings of mankind on the planet earth.
Remember fundies, it is Satan that gave us the "gift" of knowledge. Every time we think we know something, we somehow screw up somewhere. We really need to stop claiming we know things that we cannot possibly know!