1. Paleontological Institute and Museum, University of Zurich, Karl-Schmid-Str. 4, 8006 Zurich, Switzerland
2. Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Campus, Midlothian EH25 9RG, UK
3. Department of Orthopaedic Surgery, University of California at San Francisco, 513 Parnassus Avenue, S-1164, San Francisco, CA 94143-0514, USA
4. Clinic for Small Animals—Neurosurgery, Neuroradiology and Clinical Neurology, Justus Liebig University Giessen, Frankfurter Str. 114, 35392 Giessen, Germany
5. Institute of Zoology and Evolutionary Research, Friedrich-Schiller University Jena, Erbertstr. 1, 07743 Jena, Germany