Biologists generally agree that birds and dinosaurs are somehow related to one another. The agreement ends there. Hypotheses regarding dinosaurian and avian evolution are unusually diverse – and often at odds with one another. Confusion consequently reigns over a broad spectrum of unanswered questions dealing with avian origins and the biology of dinosaurs and early birds. This confusion has been exacerbated by a paucity of serious attempts to synthesize and evaluate available data on the details of avian and dinosaurian evolution. Too often, the job of summarizing current knowledge of these subjects has fallen to well-meaning but naïve lay authors or reporters. Consequently, both the public and the scientific community have often been misled by widespread dissemination of sensational but weakly founded hypotheses.