title: Classics revisited. History of reptile placentology: Studiati's early account of placentation in a viviparous lizard.
abstract: Although placental diversity in mammals received growing attention in the 1600s through the early 1800s, placentation was not documented in reptiles until the mid-19th century. In his classic 1855 study on a viviparous lizard, Cesare Studiati (University of Pisa) described a structural/functional arrangement of fetal and maternal tissues that meets contemporary criteria for recognition of placentation. Through the fortuitous selection of a highly placentotrophic species, Chalcides chalcides, Studiati recognized the functional role of placental tissues in provision of oxygen as well as nutrients. Although Studiati worked in a pre-evolutionary milieu and without the benefits of histological techniques, his findings revealed that viviparous reptiles could exhibit placental specializations that paralleled those of mammals. Accordingly, his classic paper initiated a highly productive body of research that has continued to the present and highlighted specializations of a species that has figured importantly in placental research.
authors.affiliation: Dept. of Biology and Electron Microscopy Facility, Trinity College, Hartford CT, USA. Electronic address: daniel.blackburn@trincoll.edu.
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Blackburn
authors.affiliation: Dept. of Life Sciences, University of Siena, Via A. Moro, 53100 Siena, Italy.
authors.forename: Anna Marie
authors.initials: AM
authors.lastname: Avanzati
authors.affiliation: Dept. of Life Sciences, University of Siena, Via A. Moro, 53100 Siena, Italy.
authors.forename: Luana
authors.initials: L
authors.lastname: Paulesu
mesh_terms: D000818:Animals; D005260:Female; D049672:History, 19th Century; D008116:Lizards / Q000502:physiology*; D010828:Physiology, Comparative / Q000266:history*; D010929:Placentation; D011247:Pregnancy; D052286:Viviparity, Nonmammalian
keywords: Comparative placentation; Fetal membranes; History of science; Lizard placenta; Placentotrophy