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
Specimens of Archaeopteryx under his control and full exposed, his subsequent study and monograph was the first comprehensive description of an "Archaeopteryx" specimen that had not been disarticulated. The Berlin specimen of "Archaeopteryx" is to date the most complete existing specimen of this genus, and is widely regarded as one of the most beautiful fossils in the world. Its well-preserved skeleton and the preserved feathers of its wings and tail have made it of considerable interest to a wide range of scientific study, beginning with Wilhelm Dames and Carl Vogt shortly following its discovery. This iconic fossil preserves the animal with an articulated