based on the theory of evolution we would expect to see an abundance of transitional forms to be present in the fossil record. But when we do look at the fossil evidence we just don't see it. We see that the major species come into existence at specific times and their form and structure is still exactly the same as their form and structure today.
While evolutionary theory does make such predictions (and as Cofty showed Tiktaalik is one such example). The problem with this statement is that it fails to acknowledge that fossilization is extremely rare, is most likely to happen to species that were abundant and around for a long time, and we have only discovered a tiny fraction of the fossils that did form. We keep finding new fossils that match the predictions of evolution theory.
It ignores that evolution does not always happen at a gradual pace. Punctuated equilibrium is the other mode where evolution happens rather quickly (thousands of years, not millions). As a result fossils are unlikely to be recorded in such a tiny geological time frame.