On the origins of birds: the sequence of character acquisition in the evolution of avian flight

Assessment of competing theories for the evolution of avian flight is probl ematic, and tends to rest too heavily on reconstruction of the mode of life of one or a few specimens representing still fewer species. A more powerfu l method is to compare the sequence of character acquisition predicted by t he various theories with the empirical sequence provided by cladistic phylo geny Arboreal and cursorial theories incorrectly predict the sequence of ch aracter acquisition for several key features of avian evolution. We propose an alternative 'pouncing proavis? model for the evolution of flight. As we ll as being both biologically and evolutionarily plausible, the pouncing pr oavis model correctly predicts the evolutionary sequence of all five key fe atures marking the evolution of birds.