Archaeopteryx of "Archaeopteryx" bones appear poorly vascularized; in living vertebrates, poorly vascularized bone is correlated with slow growth rate. They also assume that all known skeletons of "Archaeopteryx" come from juvenile specimens. Because the bones of "Archaeopteryx" could not be histologically sectioned in a formal skeletochronological (growth ring) analysis, Erickson and colleagues used bone vascularity (porosity) to estimate bone growth rate. They assumed that poorly vascularized bone grows at similar rates in all birds and in "Archaeopteryx". The poorly vascularized bone of "Archaeopteryx" might have grown as slowly as that in a mallard (2.5 micrometres per day) or as fast as
Granger Archaeopteryx Granger Archaeopteryx The Granger Archaeopteryx is a British single-engined, tailless parasol monoplane designed and built in the late 1920s by two brothers, R.F.T. and R.J.T. Granger. The sole example built is currently under restoration for flight. The layout of the Archaeopteryx was inspired by the tailless swept-winged Westland-Hill Pterodactyl, itself derived from the aircraft of J. W. Dunne. These aircraft had been designed to resist stalling and to allow easy and safe recovery if they did. The Archaeopteryx follows the Dunne D.7 in being a parasol wing monoplane, however it differs in being the first aircraft of tailless swept configuration