if something is, in principle, predictable, then a sufficiently complete explanation must, in principle, make complete predictions (among other things) about it. But many intrinsically unpredictable things can also be explained and understood.
The idea that evolution is a theory that explains how things get to be yet cannot predict the existence of elephants—it explains them but doesn’t predict them. Explanations then are more important than predictions because they lead to understanding of the unpredictable parts of reality.
