Suppose for the moment, that mutations can make new life forms. If a creature changes, that is, evolve, they must change slowly – you wouldn’t expect a chicken egg to hatch and a cat. But in the fossil record you see vast changes of organisms without any intermediate steps.
Here are a few examples. Notice the change between fish to amphibians. All of a sudden you have an organism with a pelvis ! How about a bat?
Reference: M. Denton, Evolution: A Theory In Crisis, pgs.167,168