title: A well-preserved Archaeopteryx specimen with theropod features.
abstract: A nearly complete skeleton of Archaeopteryx with excellent bone preservation shows that the osteology of the urvogel is similar to that of nonavian theropod dinosaurs. The new specimen confirms the presence of a hyperextendible second toe as in dromaeosaurs and troodontids. Archaeopteryx had a plesiomorphic tetraradiate palatine bone and no fully reversed first toe. These observations provide further evidence for the theropod ancestry of birds. In addition, the presence of a hyperextendible second toe blurs the distinction of archaeopterygids from basal deinonychosaurs (troodontids and dromaeosaurs) and challenges the monophyly of Aves.
authors.affiliation: Forschungsinstitut Senckenberg, Division of Ornithology, Senckenberganlage 25, D-60325 Frankfurt am Main, Germany. Gerald.Mayr@senckenberg.de
authors.forename: Gerald
authors.initials: G
authors.lastname: Mayr
authors.forename: Burkhard
authors.initials: B
authors.lastname: Pohl
authors.forename: D Stefan
authors.initials: DS
authors.lastname: Peters
mesh_terms: D000818:Animals; D005075:Biological Evolution; D001717:Birds; D001842:Bone and Bones; D025061:Dinosaurs; D005241:Feathers; D005580:Fossils; D005858:Germany; D012863:Skeleton