Archaeopteryx with Dinosaur Affinity

More on the relationship of Archaeopteryx to theropod dinosaurs


Newly-Announced Archaeopteryx Specimen Shows Closer Affinity With Dinosaurs

The December 2, 2005 issue of Science contains a paper by Mayr et al that outlines the features of the tenth skeletal example of the urvogel Archaeopteryx. Like all previous examples, this one was originally privately held, in this case since the 1970s by a former employee of one of the Solnhofen quarries. Upon his death, his widow approached the Senckenberg Museum, Frankfurt, Germany, about a possible sale. Ultimately, an anonymous individual acquired the specimen which will be curated by the Wyoming Dinosaur Center, Thermopolis, Wyoming on long-term loan some time in 2006-2007, with a cast to be retained by the Senckenberg.

Archaeopteryx lithographicaThe Termopolis specimen is only slightly dissociated and very complete on a single limestone slab. In addition to exquisitely-preserved bones, the impressions of both wing and tail feathers are present. Several features point out the close association of Archaeopteryx with the theropod dinosaurs. The skull is the best-preserved of all the specimens to date, and the only one preserved in dorsal view, allowing for the study of previously poorly-known features. The palatine bone is four-pronged as in theropods, as opposed to three-pronged as in more modern birds. Further evidence of the theropod nature of Archaeopteryx can be found in the foot. The anklebones are preserved in frontal view, clearly showing that it had the same kind of ankle as the theropod dinosaurs. Additionally, preservation of the foot shows characteristics like the “raptors”, in that it possessed a hyperextendible second toe, a feature previously evident in birds only in the “flying raptor” Rahonavis from the Cretaceous of Madagascar. Another feature evident in the foot of the new specimen is that the first toe is NOT reversed as in perching birds, therefore indicating that Archaeopteryx was not fully-arboreal (perhaps lending additional credence to the “ground up” theory of bird origins – though not mentioned in the paper). The features present in this specimen will provide much fuel in the debate upon both the origins of flight in birds and the relationship of Archaeopteryx to both theropod dinosaurs and more advanced birds for years to come.

Mayr, G, Pohl, B & Peters, DS. A Well-Preserved Archaeopteryx Specimen with Therapod Features. Science, 310, 1483 - 1486, (2005).