Historical perspective on developmental concepts and terminology

Abstract

In their ontogeny and phylogeny all living beings are historical entities. The revolution in biology of the 18th and 19th centuries that did away with the scala naturae according to which we humans, the acme of creation, "made a little lower than the angels," also led to the gradual realization that a humble one-celled protist ("protoctist"), such as Entamoeba histolytica of ill repute [Margulis and Chapman, ] has the same 4-billion-year phylogeny as that of Homo sapiens, vivid testimony to common ancestry and the relatedness of all living beings on earth. The group of medical geneticists who assembled at the NIH, Bethesda, MD this January to address terms pertaining to human ontogeny, did so in the long tradition of Sydenham, Linnaeus, Meckel, Geoffroy St-Hilaire père et fils, Wilhelm His and so many others before who had over the previous two centuries wrestled as earnestly as they could with concepts of "classification" and nomenclature of developmental anomalies. The prior massive need for classification per se in medical morphology has diminished over the years in favor of ever more sophisticated understanding of pathogenesis and cause through experimental biology and genetics; however, in the winter of 2013 it was still found prudent to respect terminological precedent on general terms while recognizing recent advances in developmental pathology requiring clarification and definition of special terms. Efforts along similar lines instigated by the German Society of Anatomists at their first meeting in Leipzig in 1887 culminated, after intense years of work by hundreds of experts and consultants under the goad of Wilhelm His, in the Basel Nomina Anatomica [BNA, His (1895)]. His, himself, stated prefatorily that the BNA had no legislative weight, only an evanescent consensus of many to be amended in the future as needed and indicated. Without hubris, no one before or after will do the same. The more substantial the consensus the more permanent the structure. After some 120 years the BNA is alive and flourishing. Now retitled Terminologia Anatomica, it has been amended and added to many times, is still in Latin but now with synonyms in English, the new lingua franca of science, for every anatomical, histological and embryological term. May our successors be equally effective.