Avian Evolution

Gerald Mayr is a German paleontologist who is Curator of Ornithology at the Senckenberg Research Institute in Frankfurt am Main, Hesse. He has published extensively on fossil birds, especially the Paleogene avifauna of Europe. He is an expert on the Eocene fauna of the Messel pit.

Foreword ix

Preface xi

Acknowledgments xiii

Chapter 1 An Introduction to Birds, the Geological Settings of Their Evolution, and the Avian Skeleton 1

Birds Are Evolutionarily Nested within Theropod Dinosaurs 2

The Geological Settings of Avian Evolution in a Nutshell 4

Characteristics of the Avian Skeleton 6

Chapter 2 The Origin of Birds 18

Archaeopteryx: The German “Urvogel” and Its Bearing on Avian Evolution 19

The Closest Maniraptoran Relatives of Birds 22

Feather Evolution 32

The Origin of Avian Flight 37

Chapter 3 The Mesozoic Flight Way towards Modern Birds 43

Jeholornithids: Early Cretaceous Long-Tailed Birds 44

Confuciusornis, Sapeornis, and Kin: Basal Birds with a Pygostyle 45

Ornithothoraces and the Origin of Sustained Flapping Flight Capabilities 50

The Ornithuromorpha: Refinement of Modern Characteristics 55

Ornithurae and the Origin of Modern Birds 59

Chapter 4 Mesozoic Birds: Interrelationships and Character Evolution 64

The Interrelationships of Mesozoic Birds: Controversial Phylogenetic Placements and Well-Supported Clades 65

Character Evolution in Mesozoic Birds 68

Ontogenetic Development of Mesozoic Birds 81

Chapter 5 The Interrelationships and Origin of Crown Group Birds (Neornithes) 84

Phylogenetic Interrelationships of Neornithine Birds 85

The Mesozoic Fossil Record of Neornithine-Like and Neornithine Birds 88

Chapter 6 Palaeognathous Birds (Ostriches, Tinamous, and Allies) 94

The Interrelationships of Extant Palaeognathae 95

Early Cenozoic Palaeognathous Birds of the Northern Hemisphere 95

Long-Winged Ostriches, Rheas, and Tinamous 97

Short-Winged Palaeognathous Birds 101

Biogeography: A Textbook Example of Gondwanan Vicariance Has Been Dismantled 105

Chapter 7 Galloanseres: “Fowl” and Kin 107

Galliformes: From Herbivorous Forest Dwellers to Seed Eaters of Open Landscapes 108

The Waterfowl 113

Gastornithids: Giant Herbivorous Birds in the Early Paleogene of the Northern Hemisphere 118

Dromornithids (Mihirungs or Thunderbirds): Gastornis-Like Birds from Australia 120

Pelagornithids: Bony-Toothed Birds 121

Chapter 8 The “Difficult-to-Place Groups”: Biogeographic Surprises and Aerial Specialists 125

The Columbiform Birds: Doves, Sandgrouse, … and Mesites? 126

The Hoatzin: A South American Relict Species 127

Turacos and Cuckoos 129

Bustards 131

The “Wonderful” Mirandornithes, or How Different Can Sister Taxa Be? 132

Strisores: The Early Diversification of Nocturnal Avian Insectivores 136

Chapter 9 Shorebirds, Cranes, and Relatives 147

Charadriiformes: One of the Most Diverse Groups of Extant Birds 148

From Rail to Crane 156

Chapter 10 Aequornithes: Aquatic and Semi-Aquatic Carnivores 161

Loons: Foot-Propelled Divers of the Northern Hemisphere 162

Pelagic Tubenoses and Albatrosses 164

Penguins: More Than 60 Million Years of Flightlessness 168

The Polyphyletic “Pelecaniformes” and “Ciconiiformes” 174

Late Cenozoic Turnovers in Marine Avifaunas 187

Chapter 11 Cariamiforms and Diurnal Birds of Prey 189

Seriemas and Allies: Two Species Now, Many More in the Past 190

Diurnal Birds of Prey: Multiple Cases of Convergence among Raptorial Birds 197

Chapter 12 The Cenozoic Radiation of Small Arboreal Birds 204

The Courol and Mousebirds: Two African Relict Groups 205

The Long Evolutionary History of Owls 210

Parrots and Passerines: An Unexpected Sister Group Relationship and Its Potential Evolutionary Implications 212

Trogons, Rollers, and Woodpeckers: Cavity-Nesters with Diverse Foot Morphologies 223

Chapter 13 Insular Avifaunas Now and Then, on Various Scales 233

Islands and Isolated Continents as Refugia 234

The Evolution of Flightlessness in Predator-Free Environments 235

Insular Gigantism and Islands as Cradles of Unusual Morphologies 241

Glossary 245

References 248

Index 289