Dinosaurs did not evolve into birds. They carried similar DNA and bone structure. Based on what I know about the natural world, which is pretty limited, I'd say, based upon observation that Dinosaurs were an end unto themselves based on size evolution which ultimately did them in. If evolution cannot create mistakes, then how do you explain a rise in mental illness? Though intelligence and knowledge have increased?
I'd come closer to believing that birds evolved from fish than dinosaurs. Gliding through water is a bit like flying. Facing a new enemy out of water could cause flight. Same concept, different environment.
Ultimately, all forms of life now on this planet has a distant cousin and we call them dinosaurs in the generic sense. While I do not believe that the human being evolved from the ape, I do believe that there was a sub species of human being and that human being mated with it. Even the Bible tends to suggest this with its description of Eden, the fall of Adam and Eve, how they had children and then their child "took a wife". Unless the inference is incestuous. At which point we would believe that all of man kind is inbred.
But to suggest that birds are descendants of say, Tyranasaurus Rex is too much a logical leap, even for nature. Fossils bear out a record of likeness in organisms. Further, it seems that many times, any evidence of ancient animals bears a distinct likeness.
The wooly mammoth looks much like the elephant of today, and granted the elephant is smaller. But the elephants mode of travel is on its feet. Just as it was during wooly mammoth times.
I do think that birds have become more aerodynamic and streamlined over time. This would make sense in terms of adaptation and survival. Which is why the dodo bird never survived. That and the fact that the meat was not very good. I mean, why take care to keep a good population of bird if it isn't quite pallatable? Back in the mid 17th century, no one was concerned about the plight of the dodo bird. Oddly, the island environment which once made a safe haven for them, ended up helping in their demise. There was no place for them to migrate and islanders were bringing dogs and cats with them.
The Rodrigues Solitaire and the Dodo bird had thick beaks, legs and claws. They were similar in form and as I look at sketches of them, I see the old world thickness. But I do not envision dinosaur.
What I can envision is a cousin of the bird way back when, in a more giant form. Kind of like in terms of a zebra and an elephant. Or a mouse and a kangaroo.
But I do not believe some earth thundering dinosaur became a bird. That doesn't fit in with the patterns of nature and evolution.