Archaeornithes now thought to represent a single species, "Archaeopteryx lithographica", the "Archaeornis" being the Berlin specimen of "Archaeopteryx". While rarely used by palaenthologists today, the term was revived by the ornithologists Livezey and Zusi in 2007, for a group comprising Archaeopterygidae and the Confuciusornithidae. Archaeornithes The Archaeornithes, classically Archæornithes, is an extinct group of the first primitive, reptile-like birds. It is an evolutionary grade of transitional fossils, the primitive birds halfway between non avian dinosaur ancestors and the derived modern birds (avian dinosaur). Fossils of early birds were poorly known until the late 20th century. Of those known, all fell into
Specimens of Archaeopteryx than flight. Pennaceous feathers thus represent an exaptation and were only later adapted for aerodynamic capabilities, a function that was apparently convergent among different groups within Avialae. In February 2014, the existence of a twelfth specimen was announced from an Altmannstein quarry near the Schamhaupten district of Bavaria. This specimen was unearthed by a private collector in 2010.. Based on a new diagnosis for the genus Archaeopteryx, by the German paleontologist Oliver Rauhut c.s., the Berlin, Eichstätt, Solnhofen, Munich, Daiting, Thermopolis, 11th, and 12th specimens can be referred to this genus with high certainty. Specimens of Archaeopteryx Archaeopteryx fossils from