Before Schleiden and Schwann, Darwin and Mendel there passed briefly a towering giant, Johann Friedrich Meckel the Younger (1781-1833), now glimpsed only fleetingly and obscurely through the mist of time and former controversies, who can nowadays easily and clearly be identified as the father of a "pre-modern" developmental biology. At his beginning this prodigiously gifted physician-scholar had, as one would say nowadays, an unfair advantage, his cradle having been rocked, as it were, by the preparators in his father's and grandfather's huge collection of normal and abnormal anatomical "specimens" in the home in which he was born and raised including his father's own skeleton (with two anatomical anomalies!). Initially reluctant to follow in the steps of his illustrious anatomist/physician grandfather and father, he nevertheless early demonstrated extraordinary gifts in anatomy and zootomy. Napoleon's conquest of his homeland notwithstanding, Meckel spent at least 2 extremely fruitful years in Paris, under the tutelage of Cuvier, but also in close contact with Geoffroy St. Hilaire (Etienne), Lamarck, and von Humboldt. He not only translated Cuvier's Leçons d'anatomie comparée into German but also greatly enriched this pivotal treatise with observations of embryonic and malformed fetuses and animals only of passing interest to his mentor. In his numerous publications, Meckel was the first to relate abnormal to normal development, define anomalies of incomplete differentiation (vestigia), but, most importantly, to relate those malformations known in humans to those that are normal adult developmental states in "lower" animals (atavisms). Thus, Meckel's three-fold parallelism of the scala naturae, normal ontogeny, and the malformations in humans and animals makes him a recapitulationist par excellence, however, without ever venturing into a fully articulated and explicit theory of descent. Today Meckel is remembered solely as the discoverer of the syndrome and cartilage named after him, and as having interpreted, correctly, the developmental nature of the "Meckel" diverticulum. It is virtually unknown that Meckel also first enuntiated the concept and distinction between primary and secondary malformations/anomalies, introduced the notion of heredity into the causal analysis of congenital anomalies, was the father of syndromology (the Meckel syndrome), had a clear understanding of pleiotropy and heterogeneity, and can unequivocally be regarded as the father of developmental pathology. In hindsight, and inspite of much professional success, Meckel emerges as a tragic figure in the history of biology, his life cut short at 52 without an ability to incorporate cell theory and the embryological insights of his younger contemporaries into his intellectual edifice which might have made it possible for him to finally and clearly see "analogy" (now homology), of which he was the greatest expert in his era, as incontrovertible evidence for descent. In that case, Darwin and Haeckel might have even had the courtesy of a tip-of...

In some bats, a noseleaf is thought to help focus echolocation calls emitted through the nostrils. I studied the ontogenetic mode of the rhinarial cartilages and the associated facial muscles to assess how these rhinarial infrastructures interact with the noseleaf, and the inferred function of such a rhinarial complex. This study focuses on developmental stages of Hipposideros diadema and Lavia frons. Based on new data on these two rhinolophoids and a review of former studies concerning rhinopomatids, rhinolophoids and phyllostomids, the functional and phylogenetic implications of the rhinarial complex among leaf-nosed Microchiroptera are evaluated by the current study. Nasal emitting forms evolved several times independently in the Microchiroptera and share various features, irrespective of their phylogenetic position: the nostrils lie dorsally; the noseleaf has a well-developed horseshoe-shaped plate; the cartilago cupularis bears a large processus cupularis; M(iv) is extended on the lateral plate of the processus alaris superior. The unique similarities of the ontogenetic process of the nasal ‘resonators’ support the assumption that the rhinolophids + megadermatids and rhinopomatids may represent a natural group. In some features, the rhinolophids + megadermatids differ significantly from the phyllostomids. The noseleaf has a median flap and anterior-facing pockets. The processus alaris superior is half-tube-shaped or included in the lateral wall of the cupula nasi anterior. The cartilago accessoria and the attendant musculature perform an important function for supporting and moving the noseleaf. Similar emission of the echolocation pulses but alternative constructional designs of the external nose structures suggest that a separate history of rhinolophoids and phyllostomids might account for these differences.

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 Abstract Göbbel, L., Fischer, M.S., Smith, T.D., Wible, J.R. and Bhatnagar, K.P. 2004. The vomeronasal organ and associated structures of the fetal African elephant, Loxodonta africana (Proboscidea, Elephantidae). -Acta Zoologica (Stockholm) 85 : 41-52The vomeronasal organ (VNO) is a chemosensory structure of the nasal septum found in most tetrapods. Although potential behavioural correlates of VNO function have been shown in two of the three elephant species, its morphology in Loxodonta africana has not been studied. The development of the VNO and its associated structures in the African elephant are described in detail using serially sectioned material from fetal stages. The results show that many components of the VNO complex (e.g. neuroepithelium, receptor-free epithelium, vomeronasal nerve, paravomeronasal ganglia, blood vessels, vomeronasal cartilage) are well developed even in a 154-day-old fetus, in which the VNO opens directly into the oral cavity with only a minute duct present. However, the vomeronasal glands and their ducts associated with the VNO were developed only in the 210-day-old fetus. Notably, in this fetus, the vomeronasal-nasopalatine duct system had acquired a pathway similar to that described in the adult Asian elephant; the VNOs open into the oral cavity via the large palatal parts of the nasopalatine ducts, which are lined by a stratified squamous epithelium. The paired palatal ducts initially coursed anteriorly at an angle of 45 ° from the oral recess and /or the oral cavity mucosa, and merged into the vomeronasal duct. This study confirms the unique characteristics of the elephant VNO, such as its large size, the folded epithelium of the VNO tube, and the dorsomedial position of the neuroepithelium. The palatal position and exclusive communication of the VNO with the oral cavity, as well as the partial reduction of the nasopalatine duct, might be related to the unique elephantid craniofacial morphogenesis, especially the enormous growth of the tusk region, and can be seen as autapomorphies.

S U M M A R YWe present the first data on our comparative genomic hybridization (CGH)-based strategy for the analysis of ancient DNA (aDNA) samples extracted from fetuses preserved in the Meckel Anatomical Collection in Halle, Germany. The collection contains numerous differently fixed ancient samples of fetal malformations collected from the middle of the 18th to the early 19th century. The main objective of this study is to establish a "standard" aDNA extraction and amplification protocol as a prerequisite for successful CGH analyses to detect or exclude chromosomal imbalances possibly causative for the malformations described for the fetuses.