paleornithology

Paleornithology is the scientific study of extinct birds and their evolutionary history, drawing on fossil evidence to illuminate how modern birds (Neornithes) arose from their dinosaurian ancestors and how avian diversity developed through the Mesozoic and Cenozoic. The field integrates comparative anatomy, paleobiology, systematics, and taphonomy, and intersects with vertebrate paleontology, atmospheric and climatic history, and developmental biology. Through fossils such as skeletal remains, feather impressions, eggs and nests, researchers infer growth, locomotion, flight capability, and ecological roles of ancient birds.

The discovery of Archaeopteryx in the 1860s established the bird-dinosaur relationship and set early directions for paleornithology. Since then, researchers have described diverse groups such as Enantiornithes, Hesperornithiformes, Ichthyornithes, and Confuciusornithiformes, revealing a widely varied avifauna across continents. Methods include meticulous comparative anatomy and cladistic analysis to place fossils in evolutionary trees, paleohistology to study bone microstructure, and imaging techniques such as CT scanning to examine internal anatomy. Fossil feathers provide data on coloration and aerodynamic properties, while eggs, nests, and trace fossils inform reproductive biology and behavior. Isotopic analysis and ecological inference shed light on diets and habitats.

Paleornithology clarifies the origin of flight, wing and feather evolution, respiration and metabolism in birds, and patterns of extinction and survival around major events such as the Cretaceous-Paleogene boundary. The field faces biases from incomplete fossil records and preservation, but advances in imaging, dating, and expanded fieldwork continue to refine our understanding. Molecular data are rare but can complement morphology in exceptionally preserved specimens. The discipline is closely linked to modern ornithology, using living birds as models for interpreting ancient forms.