Birds are now considered "living dinosaurs" by evolutionary theorists. The putative descent of birds from dinosaurs has become established as one of the most popular evolutionary transitions. In recent years, apparent bird-like features have been increasingly detected in theropod dinosaurs, and a majority of apparent avian traits have been found to be represented in various dinosaur groups. Therefore, a gradual transition from dinosaurs to birds is considered by evolutionary theorists well supported by fossil evidence. Only a few characteristics are considered suitable to distinguish between birds and dinosaurs. Thus, one could no longer draw a line between dinosaurs and birds today according to evolutionists. The occurrence of a number of bird-typical traits in dinosaurs and Mesozoic birds is here analyzed in more detail. In which theropod groups do the traits in question occur, and what is the phylogenetic and stratigraphic position of the genera in question? Is it supported by data that the apparent avian features were added step by step? The cladistic methodology is used to test whether consistent evolutionary hypotheses can be made within an evolutionary interpretive framework in light of the fossil evidence. The following traits or trait complexes are examined: feather types and flight ability, teeth and beak, brain and encephalization quotient, furcula, gastralia, rib cage, sternum, pneumaticity, air sac system and respiration, pelvis and posteriorly oriented pubis, pygostyle, fibula, wrist, and eggs, clutch, and brood care. It was concluded that even after examining the claimed fossil evidence, there are no unequivocal evolutionary transitions. Instead, the evidence confirms the creation of a variety of original basic types (created kinds) that subsequently diversified.