THE SKELETAL EVIDENCE FOR A SISTER-GROUP RELATIONSHIP OF ANSERIFORM AND GALLIFORM BIRDS - A CRITICAL-EVALUATION

The osteological basis for the proposed close phylogenetical relations hip of anseriform and galliform birds is evaluated and found to be ver y weak. Out of eleven postulated synapomorphies in cranial morphology (Cracraft 1988), three must be excluded since they express variation t hat is already covered by any of the other eleven characters. Another six of the postulated synapomorhies either cannot be verified to occur in most anseriforms and galliforms, or have a wide distribution outsi de this group. A re-analysis of the combined morphological and biochem ical data set of Cracraft and Mindell (1989) with the questionable ost eological characters excluded, does not corroborate an anseriform-gall iform sister-group relationship, but leaves the Neognathae unresolved.