Ancient Bird is 'Missing Link' To Archaeopteryx

Found @ New Scientist

Avian evolution made important advances between Archaeopteryx and the Yixian birds. "Archaeopteryx was an efficient powered flapping flyer, but lacked many of the adaptations of the skeleton seen in modern birds – especially fusions of bones that support flight muscle and reduce length of the tail," Benton told New Scientist.

Confuciusornis was a strong flyer, with flight muscles anchored on the wing by a large ridge of bone known as the deltopectoral crest, and on the body by a large fused sternum.

With a pair of separate sternal plates and a smaller deltopectoral crest, Eoconfuciusornis is more advanced than Archaeopteryx, and the most primitive, as well as the earliest, member of the Confuciusornis family.