Suppose we look up at a clear night sky, and conclude that, because bright stars appear to be closer than dimmer stars (based on our experience that brighter street lamps our closer than dimmer street lamps), we need not invent telescopes to view them in detail and apply the parallax (basic trigonometry) to discern their true distances. That's just what advocates of ID would have us do.
Liberals figured out too many people were opposed to gun control, so they started preaching to us about gun safety. Now Creationists have their own less offensive, harder to immediately dismiss Intelligent Design to slip into our science curriculum!
The odds of a "correct" mutational change occurring in the correct sequencing in random are so overwhelming that the odds of such a rachis and barb structure evolving are nil.
Irreducible complexity sides with Intelligent Design to a much greater degree than it does with Darwinian theory.
These are theories, not proven facts. If scientists had overwhelming proof that "evolution" has occurred, they would have long, long ago called a World Symposium and changed the name to the Law of Evolution. But they don't have that proof. Now it remains to be seen if they ever will, or if any of us will be able to prove differently. After all, we hardly know why we exist, let alone how we came to be as we are!