Then Johnson moved on to examine the molecular evidence. To prove Darwinian theory, he explained, the evidence would have to show that
the common ancestors and transitional intermediates really existed in the living world of the past, and that natural selection in combination with random genetic changes really has the kind of creative power claimed for it. It will not be enough to find that organisms share a common biochemical basis, or that their molecules as well as their visible features can be classified in a pattern of groups within groups. The important claim of Darwinism is not that relationships exist, but that those relationships were produced by a naturalistic process in which parent species were gradually transformed into quite different descendant forms through long branches (or even thick bushes) of transitional intermediates, without intervention by any Creator or other non-naturalistic mechanism.
The facts of molecular biology tell us man and apes are 95 percent similar, or that man and a banana are 25 percent similar, in their physiological makeup. But the facts don’t tell us how the similarities or dissimilarities came to exist. Scientists fill in that blank the way they do because they assume Darwinian evolution is true.
— Marvin Olasky, from Monkey Business, p. 190