The spherical earth is a scientific theory.
Gravity is a scientific theory.
Mendelian genetics is a scientific theory.
DNA is a scientific theory.
And Evolution is a scientific theory.
Here's the thing about scientific theories:
They all work. They can be proven.
Creationism, Intelligent Design, Adam and Eve and every other Biblical metaphor can't be tested or proven by scientific means.
They remain articles of "faith" or belief.
More to the point: The Bible is a metaphor and can't be taken literally. It was never meant to do that until it was used by political clegy to control the laity.
Remember that whenever you scratch a fundamentalist, or an evangelical, you find a politician.