most of the mutations would not show up as a difference in the fossils. an example would be a slightly different color of the eyes of a dinosaur. can you tell what the norm was? no, there is no indications of this in the fossils. therefore and change in them would not show up either. same with changes in the color of the skin.

the vast majority of bones crumple without ever leaving a trace. since the vast majority of bones would not leave a trace in the bones and the vast majority of bones are destroyed, there is very little likelyhood of us finding one.

on the other hand, there are many different species that only have a few partial examples of. perhaps one of these is actually a mutation and we have never found the evidence of the normal of that speices.

the more man learns, the more he realises, he really does not know anything.