article: Origin of birds
links: Troodontidae Ornithurae Troodon Archaeopteryx Sinosauropteryx Galloanserae Gansu Cretaceous Deinonychus Asteriornis Lower Cretaceous Liaoning Sauropsida Thomas Henry Huxley Bavaria K/T extinction event Gansus Anchiornis Paraves Jurassic Shuvuuia Neornithes Mesozoic era Bird Jehol biota Velociraptor Deinonychosauria Aves Epidexipteryx Lagerstätte Solnhofen limestone Neognathae Neoaves Confuciusornis Hesperornis Microraptor Ichthyornis China Compsognathus Germany Anchiornis huxlei Dromaeosauridae