Vertebrate palaeohistology then and now: A retrospective in the light of the contributions of Armand de Ricqlès

In addition to his many contributions to the basic anatomy and nomenclature of the osteohistology of extant vertebrates, Armand de Ricqlès has been more instrumental than any other researcher of the past half century in elucidating the structure and anatomy of the bone tissues of extinct vertebrates and in guiding the field in interpreting their meaning and application to a variety of important paleobiological problems. As a result of his pioneering work, which began with his doctoral thesis and has continued through five decades of collaborative research, we are now able to answer definitively many questions about the growth, physiology, function, and paleoecology of extinct tetrapods. In some cases we can even clarify their taxonomic status in ways unavailable through gross anatomical studies. This would have been unimaginable several decades ago, and it demonstrates how, thanks largely to the work and influence of Armand de Ricqlès, palaeohistology has been thoroughly integrated into palaeobiology.