A NEW BASAL LINEAGE OF EARLY CRETACEOUS BIRDS FROM CHINA AND ITS IMPLICATIONS ON THE EVOLUTION OF THE AVIAN TAIL

: We report on a new Early Cretaceous bird from China that sheds significant light on the evolutionary transition between primitive birds with a long bony tail and those with a short tail ending in a pygostyle. A cladistic analysis of basal birds supports the placement of the new fossil as the sister‐taxon of all pygostylians. Possessing a unique hand morphology with a phalangeal formula of 2‐3‐3‐x‐x and a reduced number of caudal vertebrae...