Often ignorant Theists will say; "If we evolved then why are the monkeys still here?"
It's important to not misrepresent evolutionary scientists. What they are claiming is that the human genus, and modern apes, hominoids,(anthropoids) stemmed from hominid ancestors of the hominidae family. (Extant related to the now extinct, not the extant).
The point is, extant humans are not supposedly related to modern apes, which would be distant cousins, but rather they are supposedly related to extinct ape-like creatures such as the Australopithecines.
I am no scientist, but it is important to get a correct understanding of the claims of evolution, so that any unfair strawman arguments aren't put forth, as that would be dishonest.
I believe that the finches' beaks can change into differently shaped beaks, therefore why shouldn't we believe that an ape-like creature could adapt, over time, just as the finches did?
Well, the difference is fundamentally that there are two different claims, logically. The changing of the shape of a beak as a fact of biological change, is not up for debate, but to says that a whole kind of organisms can change into another kind is a monumentally GRAND claim that can't merely be granted, for logical reasons.