The early history of the vertebrate calcified skeleton.
D000222:Adaptation, Physiological; D000818:Animals; D005075:Biological Evolution; D002113:Calcification, Physiologic / Q000266:history*; D049690:History, Ancient; D049691:History, Medieval; D049711:History, Modern 1601-; D006801:Humans; D009141:Musculoskeletal System; D014714:Vertebrates