So you see Genesis as a prophecy?
No. I believe -based both on what is stated in the bible -and also not specified -that Adam was created nearly 6,000 years ago (not the Earth initially).
However, I also believe he was not the first humanoid, but the first "man" by scriptural definition -not scientific definition -especially in the sense that with him specifically God initiated his plan to make men literally into gods -to be perfect and eventually be made immortal, be given spirit bodies, etc.
It is not actually stated that he was the first "man" by general definition. That is actually an assumption -the same is true of a young Earth. It is understandable that the language used can lead one to believe certain things without further study -but they are nonetheless errors.
People seem to think it is blasphemy to think there were other humans on Earth -or to think there was an Earth on which they could exist prior to Adam, so they ignore things even in the bible which indicate both an old Earth and humans besides those in Eden -not to mention science.
The bible is not focused as much on things which preceded Adam, but it actually places Lucifer and a third of the angels on Earth before the events in Eden -before Lucifer turned them against God and rebelled -and were cast back down to Earth. Satan is called destroyer. Of the demons it says they "kept not their first estate". Not only did they leave it to stage a coup against God, but they did not keep it in the sense of stewardship and management. They left it a mess -as stated in Genesis "the Earth"
had become or
became "formless and void" or "waste and ruin" -to an unspecified degree (except that which is done afterward in Genesis). Nowhere does it say the life forms of Genesis were the first -nor does it say the Earth was completely lifeless when God began to REPAIR it in preparation for Adam, Eve, etc.
So... no young Earth -no need for all to be descended from Adam -evolution is just fine -dinosaurs are still cool.... no reason for the E v C controversy...
Therefore.... scientific evidence of Adam and Eve would be much different. Even then, why wouldn't Adam be quite similar in makeup to others?
Just as God used Adam's material to make Eve, he could have referenced those who already existed. Perhaps there were some differences in Adam compared to others, but how could we know what to look for either way? How would you find one man who didn't quite belong due to lack of direct forebears -would there even be any evidence of such if God used existing "tech", as it were? If God made some tweaks and Adam was a bit different/better than others which made him more suitable for God's purposes, how would you track that down as his material mixed with that of others over time?
EDIT: The bible was written in an early human language -not one suited for the specifics of modern science (There were approximately 7,000 words in biblical Hebrew. There are presently about 171,476 words in the English language). Even today, however, one might use the word "man" to mean different things -and it might need clarification. Did one mean modern man, early man, all species ever considered man, etc.?
Things in the bible which at least hint at other humans on Earth outside of Eden are the fact that Cain found a wife in Nod when cast out of Eden -and was also worried that any people who found him would kill him. There is also the differentiation between the "sons of God" and the "daughters of men" -who were obviously compatible enough to breed. So.... even though God created Adam directly -and he was a "man", his offspring would certainly qualify as sons of God (some have assumed this must mean angels had relations with human women) as opposed to the daughters of men.
Eve is called the mother of all the "living" -not actually all those who were alive in the human sense. Adam and Eve were informed that they would live forever -not die -if they did not disobey -and would die if they did. Eternal life was on their minds. In the new testament, Adam is called the "first man" -by someone far removed from those events -who was likely not even considering the specifics of science. He was first for all scriptural intents and purposes. Even farther removed, WE put the focus on what we believe the words to mean.
What science might actually look for instead of Adam being the first human ever (that ship has pretty much sailed) -is an occurrence
some time prior to 6,000 years ago which -ironically -resulted in what scientists are warning about now -the melting of ice and rising sea levels due to OUR irresponsibility.
Notice that when this renewal in Genesis begins.... the first thing described is darkness upon the face of the deep -the waters -which were already there. Later -after shedding light on the subject -water and dry land had to be separated.
Other than evidence of such, we're talking about very supernatural abilities -concerning both how things might have become disordered and how they were ordered again.
Again, the language might suggest an initial creation if that is already in your mind, but what is actually described is tweaking the function and juxtaposition of celestial bodies in relation to each other and Earth.