Abstract:
Eighteen papers covering diverse aspects of avian paleontology—from the earliest known bird to extinct species found in Indian middens—are collected here to honor the 90th birthday of Alexander Wetmore. These are preceded by an appraisal of the current state of avian paleontology and of Alexander Wetmore's influence on it, including a bibliography of his publications in this field. John H. Ostrom analyzes the hypothetical steps in the origin of flight between Archaeopteryx and modern birds. Philip D. Gingerich confirms that Ichthyornis and Hesperornis did indeed bear teeth, that the palate in Hesperornis is paleognathous, and that these Cretaceous toothed birds appear to occupy a position intermediate between dinosaurs and modern birds. Larry D. Martin and James Tate, Jr. describe the skeleton of the Cretaceous diving bird Baptornis advenus and conclude that the Baptornithidae belong in the Hesperornithiformes, but are less specialized than Hesperornis. Pierce Brodkorb describes the first known Cretaceous land bird as forming a new order possibly ancestral to the Coraciiformes and Piciformes. E. N. Kurochkin summarizes the distribution and paleoecology of the Paleogene birds of Asia, with particular emphasis on the evolution of the gruiform families Eogruidae and Ergilornithidae. Pat Vickers Rich and David J. Bohaska describe the earliest known owl from Paleocene deposits in Colorado. Alan Feduccia transfers the Eocene genus Neanis from the Passeriformes to the Piciformes and he and Larry D. Martin go on to refer this and four other genera to a new family of Piciformes, concluding that these were the dominant perching land birds of the Eocene of North America. Storrs L. Olson describes a new species of Todidae from the Oligocene of Wyoming and refers the genus Protornis from the Oligocene of Switzerland to the Momotidae, concluding that the New World Coraciiformes originated in the Old World. Charles T. Collins describes two new species of the Eo-Oligocene genus Aegialornis and presents evidence that the Aegialornithidae should be referred to the Caprimulgiformes rather than to the Apodiformes, although they might be ancestral to the swifts. In the following paper he shows that the earliest known true swifts (Apodidae) are three nominal forms from the Lower Miocene of France which prove to be but a single species of Cypseloides, a modern genus belonging to a primitive subfamily now restricted to the New World. Stuart L. Warter describes a new osprey from the Miocene of California to provide the earliest certain occurrence of the family Pandionidae and he treats functional aspects of the evolution of the wing in Pandion. Hildegarde Howard describes a new species of flightless mancalline auk, also from the Miocene of California, which is temporally and morphologically intermediate between Praemancalla lagunensis and the species of Mancalla. Robert W. Storer analyzes Pleistocene fossils of pied-billed grebes, synonymizing Podilymbus magnus Shufeldt with modern P. podiceps and describing a new species from peninsular Florida. Kenneth E. Campbell, Jr., lists 53 species of birds, including new species of Buteo and Oreopholus, from a Pleistocene deposit in southwestern Ecuador and compares this with a fauna of similar age from northwestern Peru, both of which indicate more humid conditions in the past. Oscar Arredondo summarizes aspects of the morphology, evolution, and ecology of the gigantic owls, eagles, and vultures recently discovered in Pleistocene deposits in Cuba. Joel Cracraft analyzes variation in the moas of New Zealand, reduces the number of species recognized to 13, and suggests that several “species pairs” represent examples of sexual size dimorphism. G. Victor Morejohn reports remains of the extinct flightless duck Chendytes lawi, previously known only from Pleistocene deposits, from Indian middens in northern California and concludes that the species became extinct through human agency less than 3800 years ago.