The crown group defined by the common ancestor of living birds and all descendants; this boundary excludes Archaeopteryx and keeps Cretaceous fossil membership tied to explicit phylogenetic analyses.
Automated checks cover structure, identifiers, translations and links only; maintainer and external expert review are not complete.
Vegavis AMNH FARB 30899 from 69.2–68.4 Ma supplies the oldest highlighted crown-bird test in this atlas, but its crown-waterfowl membership is a 2025 matrix result and therefore the 69.2 Ma Neornithes range remains topology-dependent.
claim:taxon:neornithes:fossil-rangeThe highlighted Maastrichtian crown-bird candidates occur in Antarctica and Europe, whereas living Neornithes are global; these endpoints do not reconstruct a complete Cretaceous distribution or center of origin.
claim:taxon:neornithes:biogeographyNeornithes is the crown defined by the common ancestor of living birds and all descendants; Archaeopteryx is outside that crown, while Vegavis and Asteriornis require explicit fossil-placement analyses.
claim:taxon:neornithes:taxonomyNeornithes has no single crown-wide ecology; the narrow beak, enlarged jaw-muscle attachment and skull of Vegavis support underwater prey capture for that fossil only.
claim:taxon:neornithes:ecologyVegavis AMNH FARB 30899 preserves a toothless reduced-maxilla beak, hyperinflated cerebrum and specialized jaw apparatus, while Asteriornis preserves a different Maastrichtian galloanseran character combination.
claim:taxon:neornithes:morphology