The question is, how, within physical terms, does God do it?
Simple, He is God!
Simple, He is God!
I said in physical terms, not in metaphysical.
On the other hand, on occasion one can combine the two.
Apes, chimps, and other primates closely related to humans have an extra, 13th rib. Somewhere along the line, as brute, ape-like creature evolved into civilized humankind, that rib was lost.
And what does Genesis say? That woman, who is man's civilizing influence, was created out of an extra rib.
Whether God directed the alteration or is a more of the deist conception -- creating the process of the universe and letting it run -- the Bible makes it clear that humans were create out of a more ape-like species.
Since the Bible doesn't give every detail, we cannot rely on it for every scientific answer. But it tells enough for us to know we can look to science to learn how God does His work.