Archaeopteryx perhaps, to a cartilaginous sternum. The sideways orientation of the glenoid (shoulder) joint between scapula, coracoid, and humerus—instead of the dorsally angled arrangement found in modern birds—may indicate that "Archaeopteryx" was unable to lift its wings above its back, a requirement for the upstroke found in modern flapping flight. According to a study by Philip Senter in 2006, "Archaeopteryx" was indeed unable to use flapping flight as modern birds do, but it may well have used a downstroke-only flap-assisted gliding technique. "Archaeopteryx" wings were relatively large, which would have resulted in a low stall speed and reduced turning radius. The
Specimens of Archaeopteryx skeleton of a feathered animal from the same lithographic shale deposits, which would later be known as the London specimen. Coincidentally, von Meyer proposed the name "Archaeopteryx lithographica" for the feather, but not for the skeleton. Therefore, the official name of the animal was originally linked to the single feather rather than any actual skeleton, and is formally considered the original holotype. Though 1860 is often the year named for the feather's discovery, there is no proof of this date, and some authors consider it more likely to have been found in 1861, as it seems reasonable that von Meyer's