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Louis Bosc (1759-1828) was a naturalist, one of the very first "Linneans" of France, and among the founders of the first Linnean Society, the Société Linnéenne de Paris. The early part of his career as a naturalist coincided with the Revolutionary Period in France (1789-1799). During that chaotic period, he published over 30 articles with many species descriptions, 18 of which are currently recognized as valid. Here his complicated life, professional and personal, during the chaotic period of the French Revolution is described., Louis Bosc (1759-1828) était un naturaliste, un des premiers Linnéens de France et compte parmi les fondateurs de la première société linnéenne, la Société Linnéenne de Paris. Les débuts de sa carrière de naturaliste ont coïncidé avec la Période Révolutionnaire (1789-1799). Durant cette période, il a publié une trentaine d'articles et décrit un grand nombre d'espèces dont 18 sont aujourd'hui considérées comme valides. Sa vie compliquée à la fois sur le plan professionnel et personnel, pendant la période chaotique de la Révolution Française, est ici décrite.

International audience; Louis Bosc (1759-1828) was a naturalist, one of the very first "Linneans" of France, and among the founders of the first Lin-nean Society, the Société Linnéenne de Paris. The early part of his career as a naturalist coincided with the Revolutionary Period in France (1789-1799). During that chaotic period, he published over 30 articles with many species descriptions, 18 of which are currently recognized as valid. Here his complicated life, professional and per-sonal, during the chaotic period of the French Revolution is des-cribed.; Louis Bosc (1759-1828) était un naturaliste, un des pre-miers Linnéens de France et compte parmi les fondateurs de la pre-mière société linnéenne, la Société Linnéenne de Paris. Les débuts de sa carrière de naturaliste ont coïncidé avec la Période Révolution-naire (1789-1799). Durant cette période, il a publié une trentaine d'articles et décrit un grand nombre d'espèces dont 18 sont aujour-d'hui considérées comme valides. Sa vie compliquée à la fois sur le plan professionnel et personnel, pendant la période chaotique de la Révolution Française, est ici décrite

Im Rahmen der vorliegenden kumulativen Dissertation (Publikationen 1–13) stelle ich Studien zur Taxonomie, Naturgeschichte und Ökologie ausgewählter und überwiegend problematischer Amphibien- und Reptiliengruppen der Sunda Inseln und angrenzender Gebiete vor, wobei auf die Synergieeffekte zwischen Freilandarbeit und sammlungsbasierter Forschung und auf den damit erzielten Mehrwert der Forschung für die Biodiversitätsforschung eingegangen wird. Die Bearbeitung der Herpetofauna in allen Distrikten von Timor-Leste (mit Ausnahme der Exklave Oecusse), inklusive der vorgelagerten Inseln, stellte einen konstruktiven Beitrag zur Arterfassung der Amphibien und Reptilien eines Landes dar, das an der südlichen Grenze des Wallacea-Hotspots liegt. Neue Verbreitungsnachweise für die Herpetofauna aus 11 der 12 aneinandergrenzenden Distrikte wurden, zusammen mit naturgeschichtlichen Daten, präsentiert. Als Ergebnis dieses Arteninventars stieg die Anzahl der ursprünglich aus Timor-Leste bekannten Amphibien und Reptilien auf über 60 Taxa, darunter mehr als 20 Kandidaten-Arten. Viele der nachgewiesenen Arten scheinen auf Timor endemisch zu sein. Zu diesen gehören der Ochsenfrosch Kaloula sp. nov., mehrere Bogenfingergeckos der Gattung Cyrtodactylus und die Agame Draco timoriensis. Zu den bemerkenswerten Entdeckungen unter den Reptilien zählen sowohl mindestens sieben unbeschriebene Arten von Cyrtodactylus, einer Gattung, die bislang nicht auf Timor nachgewiesen wurde, als auch die Erstnachweise der Gecko-Art Hemidactylus garnotii und der Gecko-Gattung Hemiphyllodactylus für Timor-Leste sowie zahlreiche unbeschriebene Skinke (Kapitel 4, Publikationen 1 & 2). Revisionen der Gattung Cyrtodactylus und der Skink-Gattungen Eremiascincus auf Timor und benachbarten Inseln, sowie die Beschreibung bisher unbekannter Arten, zusammen mit Kollegen aus den USA und Großbritannien, sind gegenwärtig in Vorbereitung. Eine auf Timor beschränkte Revision der Gattung Cyrtodactylus war nicht möglich, ohne vorab die verworrene Taxonomie einiger Arten, die außerhalb von Timor vorkommen, zu klären. Die Taxonomie dieser in angrenzenden Gebieten vorkommenden Cyrtodactylus-Arten wurde in drei Publikationen näher untersucht (Kapitel 5, Publikationen 3–5). Eine neue Cyrtodactylus-Art, die in der herpetologischen Sammlung des Senckenberg Naturmuseums Frankfurt, Deutschland, ursprünglich als C. fumosus katalogisiert worden war, wurde beschrieben; sie stammt aus Klakah, Lumajang, Ostjava, Indonesien. Die neue Art unterscheidet sich von allen Vertretern der Gattung durch eine Kombination von sieben Merkmalen (Publikation 3). Die Diversität der Cyrtodactylus-Fauna von Java wurde, ähnlich derer auf Timor, lange Zeit unterschätzt, und erst in diesem Jahrtausend wurden vier der fünf auf dieser Insel endemischen Arten beschrieben. Cyrtodactylus fumosus, eine Art, die bisher im südostasiatischen Archipel – mit Nachweisen aus Sumatra, Java, Bali, Sulawesi und Halmahera – als weitverbreitet galt, wurde neu definiert. Es konnte bestätigt werden, dass Männchen dieser Art eine präkloakale Furche aufweisen. Die Untersuchung des Holotypus und weiteren Belegmaterials aus Rurukan und vom Mount Masarang (Nord Sulawesi, Indonesien) ergab, dass diese Population von anderen Formen, die bisher als „fumosus“ bezeichnet wurden, durch eine Kombination einzigartiger Merkmale unterscheidbar ist. Cyrtodactylus fumosus konnte auf Grund seiner Merkmale als die auffallendste Art der sechs auf Sulawesi vorkommenden Bogenfingergeckos identifiziert werden (Publikation 5). Weil bislang große taxonomische Verwirrung zwischen C. fumosus und C. marmoratus herrschte, wurde die Typusserie des letzteren Taxons zum ersten Mal komplett beschrieben. Ich konnte zeigen, dass die Typusserie historisch bedingt in zwei Gruppen (mit unterschiedlichen, aber ähnlichen Seriennummern) aufgeteilt wurde, und dass die Untersuchung von Exemplaren aus nur jeweils einer der beiden Gruppen für Wirren um diese Belege verantwortlich war. Aufgrund der inkonsistenten Terminologie und Anwendung von Begriffen für Schlüsselmerkmale, die bei der Diagnose von Bogenfinger-Geckos Verwendung finden (z.B. Furche, Sulcus, Grube, Mulde, Vertiefung), wurde eine Reihe neuer und nützlicher Definitionen vorgeschlagen. Eine Vergleichstabelle für die Bogenfinger-Geckos der Sunda Inseln und Sulawesis wurde zum ersten Mal bereitgestellt (Publikation 4). Die Cyrtodactylus-Fauna der Kleinen Sundainseln, der Molukken und Sulawesis soll künftig weiter untersucht werden. Zahlreiche Museumsexemplare werden als Basis für die Beschreibung neuer Arten dienen. Die Entdeckung einer Walzenschlange der Gattung Cylindrophis in Timor-Leste führte zu einer umfassenden Untersuchung des im maritimen Südostasien weit verbreiteten Taxons C. ruffus. Eine neue Art, die in den Sammlungen des Naturalis Biodiversity Centers, Leiden, Niederlande, und der Naturhistorischen Museums Wien, Österreich, ursprünglich als C. ruffus katalogisiert worden war, konnte beschrieben werden. Die bekannten Exemplare stammen aus Grabag, Purworejo, Zentraljava, Indonesien. Die neue Art unterscheidet sich von allen anderen Gattungsangehörigen durch zahlreiche, auffällige morphologische Merkmale. Des Weiteren liegt nun eine detaillierte Beschreibung der Taxonomie-Geschichte der ähnlichen und nur vermeintlich weitverbreiteten C. ruffus vor. Scytale scheuchzeri (der Name bezieht sich auf die Beschreibung einer colubroiden Schlange) wurde aus der Synonymie von C. ruffus entfernt, C. rufa var. javanica (ein Taxon, das ursprünglich aus Borneo beschrieben worden war) als „species inquirenda“ eingestuft und die erst kürzlich beschriebene C. mirzae mit C. ruffus synonymisiert worden. Belege zur Untermauerung der Typuslokalität von C. ruffus als „Java“ wurden erbracht. Die Entdeckungen von C. subocularis und des Bogenfingergeckos Cyrtodactylus klakahensis aus Java zeigen, wie wenig wir eigentlich über die Artenvielfalt einer Insel wissen, auf der die herpetologische Erforschung Indonesiens immerhin schon vor zwei Jahrhunderten begann (Publikation 6). Die Verwandtschaftsverhältnisse innerhalb der Gattung Cylindrophis werden in einer laufenden Studie überprüft, bei der sowohl morphologische als auch molekularbiologische Methoden zum Einsatz kommen. Basierend auf Exemplaren, die ich in der Sammlung des Naturhistorischen Museums in London, UK, entdeckte, konnte ein neuer Verbreitungsnachweis für den Skink Sphenomorphus oligolepis für die Molukkeninsel Seram (Indonesien) erbracht werden. Es handelt sich um das westlichste Vorkommen dieser papuanischen Echse und dehnt ihr Verbreitungsgebiet weit in die Wallacea-Region aus (Publikation 7). Die Schwarznarbenkröte, Duttaphrynus melanostictus, die kürzlich in Madagaskar eingeführt wurde (Publikation 8), ist das Hauptobjekt der Forschung, die in Kapitel 6 präsentiert wird. Während der Freilandarbeit in Timor-Leste wurde eine Schwarznarbenkröte entdeckt, die eine Blumentopfschlange, Indotyphlops braminus, gefressen hatte. Dies wies darauf hin, dass sich diese kürzlich auch nach Timor eingeführte Kröte möglicherweise durch Prädation bestandsgefährdend auf kleine Wirbeltiere auswirken könnte, die in Timor einen außergewöhnlich hohen Grad an Endemismus zeigen (Publikation 9). Um diese potentielle Auswirkung zu bewerten, wurde der Darminhalt von über 80 zuvor konservierten Kröten aus fünf verschiedenen Habitattypen innerhalb Timor-Lestes untersucht, wobei fast 6000 Beutetiere identifiziert werden konnten. Unter diesen befanden sich ausschließlich Invertebraten aus verschiedenen taxonomischen Gruppen. Kleine staatenbildende Insekten konnten als Hauptbestandteil der Nahrung von D. melanostictus identifiziert werden. Das breite Beutespektrum weist darauf hin, dass es sich bei D. melanostictus um einen generalistischen Invertebratenfresser handelt. Obgleich die Schwarznarbenkröte im Allgemeinen keine Vertebraten zu fressen scheint, ist nicht auszuschließen, dass Vertebraten die eine morphologische Ähnlichkeit mit Invertebraten aufweisen (Typ „Wurm“), ins Nahrungsspektrum dieser Kröte passen. Daten zu den Endoparasiten von D. melanostictus wurden zusammen mit der Nahrungsanalyse präsentiert (Publikation 11). Obgleich von zahlreichen Forschern Informationen zur Nahrung und zu Endoparasiten von Froschlurchen auf der Grundlage von Untersuchungen des Gastrointestinaltraktes publiziert worden sind, wurde nie im Detail auf die Schnittführung eingegangen, die benutzt wird, um die Leibeshöhle von konservierten Exemplaren zu öffnen. Eine optimale Schnittführung, die den Zugang und das einfache Entfernen von Teilen des Verdauungstraktes bei in Flüssigkeiten fixierten Froschlurchen erlaubt, wurde vorgestellt. Dieser U-förmige Schnitt ist einfach durchzuführen und zu vermitteln und wurde bereits in Laborhandbüchern übernommen. Er ermöglicht einen besseren Zugang zu den relevanten Organen als ein kleiner ventrolateral durchgeführter Schnitt und hat eine weniger zerstörende Wirkung als der in Lehrbüchern routinemäßig aufgeführte mediane Schnitt in Form einer römischen I. Diese neue schonende Methode könnte andere Forscher dazu ermutigen, konservierte Froschlurche für Nahrungsanalysen und andere innere Untersuchungen zu nutzen und damit den wissenschaftlichen Gebrauch von Sammlungsexemplaren fördern. Für einen auf Timor vorkommenden Nachtskink (Gattung Eremiascincus) gelang zum ersten Mal die Zucht in Gefangenschaft, wobei sich zeigte, dass die Tiere lebendgebärend sind. Die Informationen zur Reproduktionsbiologie der Gattung Eremiascincus werden zusammengefasst bereitgestellt (Publikation 12). Dieses Wissen wird bei laufenden morphologischen und molekularbiologischen Revisionen ergänzend zum Einsatz kommen. Der Typus des Skinks Anomalopus leuckartii wurde in der herpetologischen Sammlung des Museums für Tierkunde Dresden, Deutschland, wiederentdeckt. Er gehört, zusammen mit anderen Exemplaren, zum Bestand der ehemaligen Sammlung von Karl Georg Friedrich Rudolf Leuckart, der einer der führenden Zoologen der zweiten Hälfte des 19. Jahrhunderts war und als Begründer der modernen Parasitologie gilt. Diese Wiederentdeckung ist ein Paradebeispiel, das aufzeigt, wie wichtig es ist, naturkundliche Sammlungen zu erhalten und zwar nicht als statische Archive sondern als aktiv zu nutzende, wertvolle Datenbanken. Die Arbeit in und an Sammlungen, in Kombination mit der bestmöglichen taxonomischen Sachkenntnis, schafft ein produktives Umfeld, das Entdeckungen, wie sie in dieser Arbeit vorgestellten werden, maßgeblich fördert und damit unweigerlich auch die moderne Biodiversitätsforschung bereichert (Publikation 13). In einer „General Conclusions“ (Kapitel 8) werden die Effekte, die sich aus der Kombination bzw. Koordination von Freiland- und sammlungsbasierter Forschung ergeben, herausgearbeitet und in einer Übersichtsgrafik veranschaulicht. Sich zum Teil ergänzende Wechselwirkungen, Synergieeffekte und ein die Einzelarbeiten verbindender iterativer Prozess, sind die Kenngrößen, mit denen sich der Mehrwert der vorgelegten Arbeit beschreiben lässt. Abschließend wird der Nutzen für die Entscheidungsträger in Natur- und Artenschutz aufgezeigt., In this cumulative thesis (papers 1–13) I investigated the taxonomy, natural history, and ecology of selected species of amphibians and reptiles from the Sunda Islands and adjacent regions, and highlighted the importance of natural history collections for biodiversity research. Several Sundaic species provided unexpected challenges, primarily because of significant problems stemming from their taxonomic history. Only the synergy of fieldwork and collection-based studies, allowed me to resolve some of these issues, as outlined below. Herpetological surveys in all districts of Timor-Leste (except the Oecusse exclave), including its offshore islands, contributed towards a comprehensive inventory of the amphibians and reptiles of this country at the southern border of the Wallacea Biodiversity Hotspot. New distribution records of amphibians and reptiles for 11 of the country’s 12 contiguous districts, along with natural history data were presented. Results of the survey work increased the number of amphibian and reptile species known to occur in Timor-Leste to > 60, including > 20 candidate species. Many of the recorded species appear to be endemic to Timor Island, including the frog Kaloula sp. nov., several bent-toed gecko species of the genus Cyrtodactylus, and the agamid Draco timoriensis. Notable reptile discoveries included at least seven undescribed Cyrtodactylus species, a genus previously not recorded from Timor, the first records of the gecko Hemidactylus garnotii and of the gecko genus Hemiphyllodactylus for Timor-Leste, and several undescribed skinks (chapter 4, papers 1 & 2). Revisions of the genus Cyrtodactylus, and the skink genus Eremiascincus on Timor and adjacent islands, including the description of new species, are currently in preparation together with colleagues from the USA and the UK. A revision of Timorese Cyrtodactylus is not possible without resolving the tangled taxonomy of some extralimital species. The taxonomy of selected non-Timorese Cyrtodactylus geckos was investigated accordingly, in three papers (chapter 5, papers 3–5). A new species of Cyrtodactylus, originally catalogued as C. fumosus in the herpetological collection of the Senckenberg Naturmuseum Frankfurt, Germany, was described from Klakah, Lumajang Regency, Jawa Timur Province, Indonesia. The new species differs from all other congeners by a combination of seven characters (paper 3). The Cyrtodactylus fauna of Java had been underestimated for centuries with four out of the five endemic species described as late as during the 2000s. Cyrtodactylus fumosus, hitherto considered widespread in the Sunda Archipelago, including the islands of Sumatra, Java, Bali, Sulawesi, and Halmahera, was redescribed and confirmed to possess a precloacal groove in males. Examination of the type specimen and additional vouchers from Rurukan and Mount Masarang, North Sulawesi Province, Indonesia, revealed that this population was distinct from other forms heretofore called ‘fumosus’ by a combination of unique morphological characters. Cyrtodactylus fumosus was identified as the most distinctive species among the six bent-toed geckos recorded from Sulawesi, differing from Sulawesi congeners by four striking characters (paper 5). Since there was also much taxonomic confusion of C. fumosus with C. marmoratus, the type series of the latter taxon was described for the first time. I was able to demonstrate that the type series actually comprises two sets of specimens, and that examination of specimens from only one set or the other was responsible for some confusion surrounding these vouchers. Owing to the inconsistent naming and application of terms for some key characters (e.g., groove, sulcus, pit, hollow, depression) used in the diagnoses of Cyrtodactylus species, a set of novel and useful definitions was proposed. A comparative table for the bent-toad geckos of the Sunda Islands and Sulawesi was provided for the first time (paper 4). Cyrtodactylus throughout the Lesser Sundas, the Moluccas, and Sulawesi will be further investigated in future studies. Several museum vouchers will be described as new species. The discovery of snakes of the genus Cylindrophis in Timor-Leste led to an investigation of the taxon C. ruffus, which is widely distributed in Maritime Southeast Asia. A new species of Cylindrophis, originally catalogued as C. ruffus in the herpetological collections of the Naturalis Biodiversity Center, Leiden, The Netherlands and the Naturhistorisches Museum Wien, Austria, was described from Grabag, Purworejo Regency, Jawa Tengah Province, Java, Indonesia. The new species can be distinguished from all congeners by several, distinct morphological features. A detailed account of the tangled taxonomic history of the similar and only putatively wide-ranging C. ruffus was provided, Scytale scheuchzeri (name referring to a colubroid taxon) was removed from the synonymy of C. ruffus, C. rufa var. javanica (a taxon originally described from Borneo) was listed as species inquirenda, and the recently described C. mirzae was synonymized with C. ruffus. Evidence was provided that the type locality of C. ruffus is Java. The discovery of C. subocularis and the bent-toed gecko Cyrtodacytlus klakahensis on Java highlights how little we know about the diversity of an island, on which herpetological research in Indonesia began two centuries ago (paper 6). The systematic relationships within Cylindrophis are being investigated in an ongoing study utilizing both molecular and morphological methods. Based on specimens discovered in the collection of The Natural History Museum, London, UK, a new distribution record for the skink Sphenomorphus oligolepis was made for Seram Island, Maluku Province, Indonesia. The find constituted the westernmost record for this species and extended the distribution of this Papuan lizard well into Wallacea (paper 7). The Asian toad, Duttaphrynus melanostictus, which was recently introduced to Madagascar (paper 8), is the main research focus of chapter 6. During field work in Timor-Leste, an Asian toad that had consumed a brahminy blindsnake, Indotyphlops braminus, was discovered. This indicated that indiscriminate foraging by this recently introduced toad species could endanger small vertebrates (paper 9). Timor shows an exceptionally high level of endemism in a wide range of faunal groups, and concerns that D. melanostictus may have a negative impact on this diversity, including vertebrates, through direct predation, had been raised by scientists. To evaluate the potential impact the feeding by D. melanostictus might have on the local fauna, gut contents of > 80 preserved toad specimens from five habitat types in Timor-Leste were examined and almost 6000 prey items identified. All prey items were invertebrates, with small eusocial insects comprising the major component of the diet. The wide prey spectrum demonstrated that D. melanostictus is a generalist invertebrate feeder. Although the Asian toad seems to not generally prey on vertebrates, vertebrate species that are morphologically similar to invertebrates in their overall appearance (worm-like gestalt) may be consumed. Data on intestinal parasites occuring in D. melanostictus were presented alongside the food spectrum analysis (paper 11). Whereas information on the diet and internal parasites of anurans based on internal examinations have been published by numerous researchers, details of the incision method used to open the abdominal cavity of preserved specimens are rarely explained. An optimal incision into the pleuroperitoneal cavity of liquid-preserved anuran specimens to gain access to and permit easy removal of parts of the digestive tract in preparation for food spectrum analyses was formally proposed. This U-shaped cut is easy to perform and teach, and it has already been adopted in lab manuals. It provides better access to the pleuroperitoneal cavity than a small ventrolateral incision, and is less destructive than the classic textbook medial “double T-incision” routinely listed in dissection protocols. This new method may encourage other researchers to use preserved anurans for the purpose of food spectrum analyses and other examinations of internal morphology (paper 10). An instance of captive breeding in a species of Timorese night skink (genus Eremiascincus) was reported, and the taxon demonstrated to be viviparous. A summary of information pertaining to the reproductive biology of other members of the genus Eremiascincus was provided (paper 12). Increased knowledge on the reproductive biology of Eremiascincus taxa will contribute to revisions of the group carried out by morphological and molecular analyses. The type of the skink Anomalopus leuckartii was rediscovered in the herpetological collection of the Museum für Tierkunde, Dresden, Germany, together with other specimens from the original collection of Karl Georg Friedrich Rudolf Leuckart, who was one of zoology’s leading scientists during the second half of the 19th century and the founder of modern parasitology. This rediscovery serves as an excellent example to highlight the importance of maintaining natural history collections, not merely as static archives but rather as valuable dynamic and lively databases. This, in combination with optimal taxonomic expertise as a bedrock, guarantees an environment, in which new discoveries, like the ones presented in this dissertation, are actively promoted, thereby inevitably advancing modern biodiversity research (paper 13). In a general conclusions section (chapter 8), the effects resulting from the combination and coordination of field work and collection-based studies are elaborated and illustrated in a diagram. The value of the studies presented in this thesis is primarily derived from specific interactions, synergistic effects, and an iterative process that connects them. Finally, the benefit for decision-makers dealing with conservation and species management is assessed.

Entomopathogenic nematodes (EPNs) are parasites of soil-dwelling insects that occur in natural and agricultural soils around the world. The current study focuses on the unexplored coastal zone of Lebanon where soil samples were taken in different sites chosen randomly along the coast like beaches, agricultural and herbaceous fields. In total, 350 soil samples were collected, mainly from the southern part of the country. An integrated approach, combining both traditional (morphological) and molecular methods, was used to characterize entomopathogenic nematode species encountered. Two named-species are added to the EPNs catalog in Lebanon from 4 samples out of the total 350 samples isolated: Heterorhabditis indica , reported for the first time in the country (samples AYAB6 and BRA20) and Steinernema feltiae (samples ANFA5 and EDA1). Furthermore, one undescribed potential entomopathogenic nematode belonging to Oscheius genus was recovered. The symbiotic bacteria from S . feltiae and H . indica were also molecularly identified through the use of five gene fragments recA , gyrB , dnaN , gltX and infB . Phylogenetic relationships of entomopathogenic nematodes and their symbiotic bacteria were inferred by using maximum-likelihood analysis. Soil studies were subsequently carried out in order to assess a possible relationship between soil parameters and their effects on EPNs. Results indicate that sandy texture and moisture are key factors for the presence and survival of EPNs in the soil in Lebanon.

International audience; In 1948, on Théodore Monod’s initiative, an expedition was mounted by the IFAN, the French institute for French West Africa, for research and field collecting. Headed by scholars from different disciplines - Bohumil Holas, an ethnologist, and Pierre Louis Dekeyser, a zoologist - it provides a particularly interesting example of combined practices in the field and of the interaction between the social and natural sciences which resulted from this. This assignment in Eastern Liberia was also one of the few colonial expeditions to take place in an independent country. In order to understand this paradox, we must situate, describe and analyse the expedition, and its research and collecting, in the institutional and scientific context of the IFAN just after the Second World War. This will enable us to shed new light on critical political and disciplinary questions concerning ethnography and zoology towards the end of the colonial era.; En 1948, une mission de recherche et de collecte est organisée par l’Institut français d’Afrique noire (IFAN) à l’initiative de Théodore Monod. Conduite par un ethnologue et un zoologiste, Bohumil Holas et Pierre Louis Dekeyser, elle fournit un cas tout à fait intéressant de mission bidisciplinaire, permettant d’interroger la mixité des pratiques de terrain et les interférences entre sciences sociales et sciences naturelles qui en résultent. La mission Dekeyser-Holas dans l’Est libérien est aussi l’une des rares missions coloniales qui se déroulent dans un pays indépendant. Interroger ce paradoxe oblige ainsi à resituer ces recherches et ces collectes dans le contexte institutionnel et scientifique de l’IFAN à la sortie de la Seconde Guerre mondiale. Décrire et analyser cette mission permet alors d’éclairer de manière inédite les enjeux politiques et disciplinaires de l’ethnographie et de la zoologie à la fin de la période coloniale.

Climate change and habitat fragmentation modify the natural habitat of many wetland biota and lead to new compositions of biodiversity in these ecosystems. While the direct effects of climate are often well known, indirect effects due to biotic interactions remain poorly understood. The water meadow grasshopper, Chorthippus montanus, is a univoltine habitat specialist, which is adapted to permanently moist habitats. Land use change and drainage led to highly fragmented populations of this generally flightless species. In large parts of the Palaearctic Ch. montanus occurs sympatrically with its widespread congener, the meadow grasshopper Chorthippus parallelus. Due to their close relationship and their similar songs, hybridization is likely to occur in syntopic populations. Such a species pair of a habitat specialist and a habitat generalist represents an ideal model system to examine the role of ongoing climate change and an accumulation of extreme climatic events on the life history strategies, population dynamics and inter-specific interactions. In Chapter I a laboratory experiment was conducted to identify the impact of environmental factors on intra-specific life-history traits of Ch. montanus. Like other Orthoptera species, Ch. montanus follows a converse temperature size rule. In line with the dimorphic niche hypothesis, which states that sexual size dimorphism evolved in response to the different sexual reproductive roles, both sexes showed different responses to increasing density at lower temperatures. Males attained smaller body sizes at high densities, whereas females had a prolonged development time. This is the first evidence for a sex-specific phenotypic plasticity in Ch. montanus. Females benefit from the prolonged development as their reproductive success depends on the size and number of egg clutches they may produce. By contrast, the reproductive success of males depends on the chance to fertilize virgin females, which increases with faster development. This may become a disadvantage for Ch. montanus as an intraspecific phenology shift may increase hybridization risk with the sibling species. Despite the widespread assumption that hybridization between two sympatric species is rare due to complete reproductive barriers, the genetic analyses of 16 populations (Chapter II) provided evidence for wide prevalence of hybridization between both species in the wild. As no complete admixture was found in the examined population, it is assumed that hybridization only occurs in ecotones between wetlands and drier parts. Reproductive barriers (habitat isolation, behavior, phenology) seem to prevent the genetic swamping of Ch. montanus populations. Although a behavioral experiment showed that mate choice presents an important reproductive barrier between both species, the experiment also revealed that reproductive barriers could be altered by environmental change (e.g. increasing heterospecific frequency). Chapter III analyzes the impact of extreme climatic events on population dynamics and interspecific hybridization. A mark-recapture analysis combined with weather records over five years provides evidence that the embryonic development in Ch. montanus is vulnerable to extreme climatic events. Strong population declines in Ch. montanus lead to a disequilibrium between Ch. montanus and Ch. parallelus populations and increases the risk of hybridization. The highest hybridization risk was found in the first weeks of a season, when both species had an overlapping phenology. Furthermore, hybrids were generally localized at the edge of the Ch. montanus distribution with higher heterospecific encounter probabilities. The hybridization rate reached up to 19.6%. The genetic analyses in Chapter II and III show that hybridization differentially affects specialists and generalists. While generalists may benefit from hybridization by an increasing genetic diversity, such a positive correlation was not found for Ch. montanus. The results underline the importance of reproductive barriers for the co-existence of these sympatric species. However, climate change and other anthropogenic disturbances alter reproductive barriers and promote hybridization, which may threaten small populations by genetic displacement. As anthropogenic hybridization is recognized as a major threat to biodiversity, it should be considered in environmental law and policy. In Chapter IV the role of hybrids and hybridization in three levels of law and the historical backgrounds of hybrids becoming a part of legal instruments is analyzed. Due to legal uncertainties and the complexity of this topic a legal assessment of hybrids is challenging and argues for species-specific approaches. Nonetheless, existing legal norms provide a suitable basis, but need to be specified. Finally, this chapter discusses different opportunities for the management of hybrids and hybridization in a conservation perspective and their necessity., Klimawandel und Lebensraumfragmentierung verändern natürliche Lebensräume vieler Feuchtgebietsarten und führen zu neuen Artenzusammensetzungen in diesen Ökosystemen. Während die direkten Auswirkungen des Klimas oft bekannt sind, sind die indirekten Auswirkungen auf biotische Interaktionen weitgehend unerforscht. In der vorliegenden Arbeit wurde der Sumpfgrashüpfer, Chorthippus montanus, als Modellart gewählt, um die Auswirkungen von Klimaänderungen auf seinen Lebenszyklus, die Populationsdynamik und Hybridisierung mit seiner weit verbreiteten Schwesterart Ch. parallelus zu untersuchen. Ch. montanus ist ein Habitatspezialist, der aufgrund seiner Ansprüche während der Embryonalentwicklung auf Feuchtgebiete angewiesen ist. Die nahe Verwandtschaft und ähnliche Balzgesänge beider Arten haben bereits in der Vergangenheit vermuten lassen, dass sie in syntopen Populationen hybridisieren. Dies konnte in dieser Arbeit mit Hilfe molekular-genetischer Methoden bestätigt werden. Des Weiteren zeigte sich, dass Habitatgeneralisten von Hybridisierung profitieren können, da hierdurch ihre genetische Diversität steigt. Bei Spezialisten wie Ch. montanus dagegen sinkt die genetische Diversität und sie scheinen ihre genetische Integrität zu verlieren. Eine Fang-Wiederfang-Studie über fünf Jahre bestätigte, dass vor allem eine Kombination aus drei reproduktiven Barrieren (Phänologie, Habitat, Partnerwahl) die genetische Verdrängung des Sumpfgrashüpfers in den untersuchten Populationen verhindert hat. Diese Barrieren können allerdings durch extreme Wetter-ereignisse verändert oder sogar aufgelöst werden, indem sie zu starken Populationseinbrüchen und einem Ungleichgewicht der syntopen Populationen führen. Ein weiteres Experiment zeigte, dass Umweltfaktoren auch den Lebenszyklus der Art beeinflussen. In Über-einstimmung mit der Nischendimorphismus-Hypothese konnte der erste Nachweis einer geschlechtsspezifischen phänotypischen Plastizität für diese Art erbracht werden. Diese könnte sich allerdings als nachteilig für Ch. montanus herausstellen, da eine höhere Dichte eine innerartliche Phänologie-Verschiebung bewirken kann, die den Reproduktionserfolg dieser Art reduzieren und das Hybridisierungsriko mit der Schwesterart erhöhen könnte. Besonders für seltene Arten mit kleinen Populationen stellt Hybridisierung eine Gefahr dar. Das letzte Kapitel der vorliegenden Arbeit beschäftigt sich daher mit der Rolle von Hybriden und Hybridisierung im Umweltrecht. Die rechtliche Bewertung stellt aufgrund von Rechtsun-sicherheiten und der Komplexität des Themas eine Herausforderung dar. Obwohl die Analyse generell eher für artspezifische Lösungen spricht, sollte Hybridisierung einen eigenständigen Status im Naturschutzrecht erhalten. Bereits existierende Rechtsnormen oder Ansätze liefern dabei eine gute Grundlage, die im Einzelnen aber konkretisiert werden müssen.

The Myrmeleontidae and Ascalaphidae of West Africa remain poorly known. This is a consequence of the limited number of insect surveys that have been conducted in the sub-Saharan region and the small number of entomologists, particularly resident entomologists, who focused their a?? ention on these groups during of the 19th and 20th centuries. Intensive collecting over the last 20 years in Mali and Burkina Faso, however, has signifi cantly increased the number of species recorded from these countries and has provided considerable new information on their distributions and ecology. More than 10% of the species collected during this period are new to science. In this contribution, the history and general state of knowledge of the Myrmeleontidae and Ascalaphidae of West Africa are reviewed and new data are presented on the biology, ecology and morphology of several species.

In the last decades, it became clear that not only molecular signals but also mechanical forces are crucial regulators of developmental processes. The molecular mechanisms via which mechanical forces mediate their control of developmental processes have been extensively investigated via in vitro studies. However, the full range of molecular signals and mechanical forces that regulate development in vivo cannot be covered with only in vitro studies. In vivo studies have just started to reveal the molecular link between mechanical forces and development. To help fill this gap, we subjected zebrafish larvae to swim-training, which presumably increases mechanical load, and investigated the effect thereof on a molecular, morphological and kinematic level during development. The zebrafish is an established model for vertebrate development and has a reproduction cycle of only three months, transparent embryos and starts to swim as early as 2 days post fertilization. A wide range of genetic analyses and tools to investigate developmental processes at various stages (embryo, larval, juvenile, adult) and levels (e.g. molecular, cellular and organ level) are available for the zebrafish. To investigate the effect of the applied flow on the swimming kinematics of larval zebrafish, we performed a detailed analysis of the swimming kinematics of zebrafish larvae in varying flow conditions at 10 days post fertilization (dpf). We used a two camera set-up (obtaining recordings from the lateral and bottom side of the tube) and a new in-house developed 3D tracker program which allowed us to take pitch and roll angles into account and to accurately track the motion of the center of mass, the lateral bending of the body and motion of the tail fin. Furthermore, our study is the first which calculated the actual swimming speed of larval fish subjected to flow by determining the ambient flow velocity near the position of the fish via particle image velocimetry and computational fluid dynamics analysis of the flow in the tube. The analysis of the swimming kinematics showed that fish subjected to flow had a higher tail beat frequency and swam faster and longer. In addition, normalized maximum curvatures during an individual swimming burst (a forward movement consisting of several tail beats) and averaged over the first three half beats were higher in the caudal fin in fish subjected to flow. These data indicate that the applied flow increased the swimming intensity during a swimming burst and time spent on swimming. Subsequently, we investigated the effect of swim-training on chondrogenesis and osteogenesis of the cranial, axial and appendicular skeleton during early larval development (5-14 dpf). Swim-training prioritized the development of cartilage and bone structures in the head and in the median fins. We furthermore demonstrated that swim-training can increase growth depending on the feeding regime, training regime and stocking density of fish in a tube during zebrafish larval development. Furthermore, swim-training increased burst frequency which indicates that swim-training not only increased swimming intensity but also swimming activity. To investigate the effect of swim-training on the gene expression during zebrafish larval development, we performed transcriptome analysis of zebrafish larvae subjected to training and control fish at 10 dpf on a quantitative and spatial gene expression level. We chose this stage because the first ossified structures (hypurals and finrays) appear in the caudal fin around 10 dpf. This analysis demonstrated that swim-training led to molecular changes in the brain, muscle and gastrointestinal system during zebrafish larval development. In addition, we investigated if swim-training affected the expression of genes involved in muscle growth and structure with quantitative real-time PCR in trained and control fish at 5 and 14 dpf. The expression of slow fiber markers was increased after ten days of swim-training, indicating that muscle can already shift towards a slower aerobic phenotype during zebrafish larval development. Furthermore, since swim-training prioritized the onset of skeletal elements in (among others) the caudal fin and fish subjected to flow had higher normalized maximum curvatures in the caudal fin, we explored the molecular link between an increased swimming activity and caudal fin development. Fish were subjected to swim-training from 5-10 dpf and we performed a whole genome microarray analysis on the caudal fins of fish at 10 dpf. From this analysis, we identified two muscle specific genes, aste1 (asteroid homolog 1) and zgc:65811, which showed an increased expression exclusively in the caudal fin. The gene aste1 contains an XPG coding domain and might be involved in DNA repair in muscle fibers. Since DNA repair plays an important role during cell division, this suggests that this gene might be implicated in cell division in muscle fibers. The gene zgc:65811 contains a domain which encodes for the CD-9 large extracellular loop region. The protein CD-9 belongs to the family of tetraspanin transmembrane proteins and is possibly involved in muscle fiber differentiation. Our study demonstrated that swim-training can increase growth and lead to morphological and molecular changes during zebrafish larval development. We furthermore showed that the applied flow generated larger peak curvatures in the caudal fin and that swim-training led to specific morphological and molecular changes in the caudal fin. Our work suggests that the zebrafish is an interesting model species to elucidate the in vivo molecular link between functional performance and morphological development.

In this article I will investigate the relations of media and ecology, arguing that the incorporation of nature and ecology as part of the media theoretical discourse should also be connected to the ecological contexts in which theory is being produced. This means a concretisation of media ecology in terms of its focus and topic to take into account the current eco-crisis, from perspectives related to animal studies, electronic waste, and even geology. In this sense, the argument of the text is simple: there is a concrete edge to media ecological theory, and in this instance it is elaborated through the themes of animals, waste, and mineral resources.

In the last decades, it became clear that not only molecular signals but also mechanical forces are crucial regulators of developmental processes. The molecular mechanisms via which mechanical forces mediate their control of developmental processes have been extensively investigated via in vitro studies. However, the full range of molecular signals and mechanical forces that regulate development in vivo cannot be covered with only in vitro studies. In vivo studies have just started to reveal the molecular link between mechanical forces and development. To help fill this gap, we subjected zebrafish larvae to swim-training, which presumably increases mechanical load, and investigated the effect thereof on a molecular, morphological and kinematic level during development. The zebrafish is an established model for vertebrate development and has a reproduction cycle of only three months, transparent embryos and starts to swim as early as 2 days post fertilization. A wide range of genetic analyses and tools to investigate developmental processes at various stages (embryo, larval, juvenile, adult) and levels (e.g. molecular, cellular and organ level) are available for the zebrafish. To investigate the effect of the applied flow on the swimming kinematics of larval zebrafish, we performed a detailed analysis of the swimming kinematics of zebrafish larvae in varying flow conditions at 10 days post fertilization (dpf). We used a two camera set-up (obtaining recordings from the lateral and bottom side of the tube) and a new in-house developed 3D tracker program which allowed us to take pitch and roll angles into account and to accurately track the motion of the center of mass, the lateral bending of the body and motion of the tail fin. Furthermore, our study is the first which calculated the actual swimming speed of larval fish subjected to flow by determining the ambient flow velocity near the position of the fish via particle image velocimetry and computational fluid dynamics analysis of the flow in the tube. The analysis of the swimming kinematics showed that fish subjected to flow had a higher tail beat frequency and swam faster and longer. In addition, normalized maximum curvatures during an individual swimming burst (a forward movement consisting of several tail beats) and averaged over the first three half beats were higher in the caudal fin in fish subjected to flow. These data indicate that the applied flow increased the swimming intensity during a swimming burst and time spent on swimming. Subsequently, we investigated the effect of swim-training on chondrogenesis and osteogenesis of the cranial, axial and appendicular skeleton during early larval development (5-14 dpf). Swim-training prioritized the development of cartilage and bone structures in the head and in the median fins. We furthermore demonstrated that swim-training can increase growth depending on the feeding regime, training regime and stocking density of fish in a tube during zebrafish larval development. Furthermore, swim-training increased burst frequency which indicates that swim-training not only increased swimming intensity but also swimming activity. To investigate the effect of swim-training on the gene expression during zebrafish larval development, we performed transcriptome analysis of zebrafish larvae subjected to training and control fish at 10 dpf on a quantitative and spatial gene expression level. We chose this stage because the first ossified structures (hypurals and finrays) appear in the caudal fin around 10 dpf. This analysis demonstrated that swim-training led to molecular changes in the brain, muscle and gastrointestinal system during zebrafish larval development. In addition, we investigated if swim-training affected the expression of genes involved in muscle growth and structure with quantitative real-time PCR in trained and control fish at 5 and 14 dpf. The expression of slow fiber markers was increased after ten days of swim-training, indicating that muscle can already shift towards a slower aerobic phenotype during zebrafish larval development. Furthermore, since swim-training prioritized the onset of skeletal elements in (among others) the caudal fin and fish subjected to flow had higher normalized maximum curvatures in the caudal fin, we explored the molecular link between an increased swimming activity and caudal fin development. Fish were subjected to swim-training from 5-10 dpf and we performed a whole genome microarray analysis on the caudal fins of fish at 10 dpf. From this analysis, we identified two muscle specific genes, aste1 (asteroid homolog 1) and zgc:65811, which showed an increased expression exclusively in the caudal fin. The gene aste1 contains an XPG coding domain and might be involved in DNA repair in muscle fibers. Since DNA repair plays an important role during cell division, this suggests that this gene might be implicated in cell division in muscle fibers. The gene zgc:65811 contains a domain which encodes for the CD-9 large extracellular loop region. The protein CD-9 belongs to the family of tetraspanin transmembrane proteins and is possibly involved in muscle fiber differentiation. Our study demonstrated that swim-training can increase growth and lead to morphological and molecular changes during zebrafish larval development. We furthermore showed that the applied flow generated larger peak curvatures in the caudal fin and that swim-training led to specific morphological and molecular changes in the caudal fin. Our work suggests that the zebrafish is an interesting model species to elucidate the in vivo molecular link between functional performance and morphological development.

Informed by scholarship on systems of ethnography, on animal studies as well as on German (post)colonialism, this article argues thus principally that Brehm's increasingly popular tales of exotic locales, soon included in high circulation magazines such as "Die Gartenlaube", in the end stand out not so much for their cultural engagement and educational-formative representation of human Otherness and difference. Instead, what makes Brehm's works most remarkable is their simultaneous and until now unnoticed popularization of non-human animals - both exotic and domestic - as part of a discursive formation of 'Germanness' and a European self-understanding. This article highlights in this context the extent in which readers find themselves wondering, given the sheer abundance of animal observations alongside a pervasive absence of humans, whether Brehm's travels constitute a failed foray into ethnography; or whether he intentionally shifted the narrative emphasis from humans to animals in order to strategically stage his explorations as a preparatory text for audiences of his later animals tales. What will ultimately be revealed in place of such seeming opposites is how the modes of perception of a German audience for both Brehm's human and animal subjects were affected through his works by almost interchangeable modes of ethnographic and zoographic representation. As a result, Brehm's works raise central questions about the synchronic and diachronic reception of his views on animals as humans and vice versa, all of which culminated in a distinct sense of superiority shared by Brehm and a receptive German audience. What impact this perception may then have had on ensuing German discourses on race, nation, and colonial expansion will be a final consideration of this article as it looks at Brehm's contemporary relevance in widely publicized events in Germany and the United States.

Despite the plenty of molecular phylogenetic studies that emerged in recent years the position of major animal clades within the phylogenetic tree is still controversial. Therefore, the field of neurophylogeny that links the morphology of the nervous system to early evolutionary events emerged as a discipline that can be helpful for the inference of phylogenetic relationships as well as for the retracing of central nervous system evolution. So far, comparative neuroanatomical investigations in arthropods and annelids have suggested that certain brain centers are highly conserved during evolution. If structures like the mushroom bodies are indeed ancestral features of the bilaterian brain, we would expect to find similar neuropils in other invertebrate phyla as well. However, so far in depth studies of the detailed neuroanatomy of numerous invertebrate taxa are lacking. The present thesis therefore focuses on adding new comparative immunohistochemical data on the nervous system of the two lophotrochozoan phyla Mollusca and Nemertea. The first part of the thesis presents an extensive survey on the detailed neuroanatomy of the lesser-known branches of the phylum Mollusca: Caudofoveata, Solenogastres, Polyplacophora, and Scaphopoda. By comparing the neuroanatomy of those different taxa it is demonstrated that the presence of two pairs of nerve cords of the medullary type is the main unifying feature of the three non-conchiferan taxa. In other respects, the great diversity of the phylum Mollusca likewise results in a considerable variability of the nervous system. Taking the results of both aplacophoran taxa, the brain as well as the nerve cords of Caudofoveata and Solenogastres are built in a conspicuous different manner. Structures that are similar in the nervous system of Caudofoveata and Solenogastres are as well present in the Polyplacophora. Thus a monophyly of Aplacophora could not be confirmed. Comparing the nervous system of the Caudofoveata, Solenogastres, and Polyplacophora, the caudofoveate brain seems to be most complex among the non-conchiferan taxa because it exclusively shows a division into discrete sections. The neuroanatomical data presented here, are therefore not in accordance with the Adenopoda hypothesis placing Caudofoveata basal within Mollusca. The second part of the present thesis concentrates on the neuroanatomy of one representative of the phylum Nemertea. The nervous system of Lineus viridis basically consists of a well developed brain that reveals no compartmentalized neuropils. Paired medullary cords emanate posteriorly from the ventral lobes of the brain while paired cerebral organs are posteriorly attached to the dorsal lobes of the brain. By presenting a detailed view on the peripheral nervous system as well, this study reveals that nemerteans possess four distinct but interconnected nerve plexus. The results indicate that a subepidermal plexus most likely belongs to the ground pattern of Lophotrochozoa. Higher brain centers like the mushroom bodies that are typical for the arthropod and annelid brain could not been identified neither in the investigated molluscan taxa nor in the nemertean species. However, the nervous system of the investigated caudofoveate, scaphopod, and nemertean species exhibit clusters of cells resembling the globuli cells that characterize the arthropod and annelid mushroom body. Those globuli-like cell clusters are located in the precerebral ganglia of caudofoveates and the cerebral organs of nemerteans, respectively. Like the mushroom bodies of arthropods and annelids the precerebral ganglia as well as the cerebral organs are involved in the processing of olfactory information. Assuming that these cell clusters are indeed homologous, the present findings argue for the existence of mushroom body-like precursor structures in the last common ancestor of all protostomes. Besides the contribution to the evolution of certain brain centers in protostomes, the neuroanatomical data obtained in the present study are used for the construction of a data matrix that will result in a phylogenetic tree that is exclusively based on neuroanatomical data.

Major animal taxa, known as phyla, each represents a basic bauplan. Among the diversity of phyla, arthropods are the most dominant on the earth. The conspicuous feature of the arthropod bauplan is the grouping of body segments into specialized units by the phenomenon of tagmosis which in insect has given rise to three body regions; head, thorax and abdomen. But the number and the nature of segments involved in composition of the insect head is still a matter of dispute among today’s evolutionary biologists. From the beginning of the dispute, there was general agreement that three mouthparts segments (mandible, maxillae, and labium) take part in the head composition, and their ganglia fuse to form the suboesophageal ganglion of the insect nervous system. However, the nature of the segments anterior to the mandible (labral/ocular, antennal, and intercalary segments) remained controversial. Modern molecular, palaeontological, and neuroanatomical studies showed that the insect head is composed of six segments; occular, antennal, intercalary, and three gnathal segments. But conflicting views are still present regarding the nature and segmental affiliation of the insect labrum. Several such modern studies imply that the labrum is a highly modified appendage of the intercalary segment, and sensory innervation of the embryonic and the adult labrum shares many similarities with that of head and thoracic appendages. However, defining criterion of an appendage implies that every appendage must be innervated by its own segmental ganglion, and the innervation pattern must include both sensory and motor elements. The aim of thesis is to investigate the motor innervation pattern of muscles of the labrum in the adult locust to reveal the evolutionary changes underlying neuronal circuitry, which might help to decide whether the labrum represents a structure that has developed during the evolution by fusion of paired appendages associated with the intercalary segment. Using Neurobiotin as a retrograde neuronal tracer, specific motor nerves of individual labral muscles were stained. Results show that all labral muscles receive innervation from both the tritocerebral lobes of the brain and the suboesophageal ganglion, except for M1, the labral compressor muscle. M1 is innervated by two motor neurons. Both tritocerebral lobes contain one soma. The axons of both neurons branch in the periphery to innervate ipsi- and contralateral muscles. The labral anterior retractor muscles, M2, are innervated by 6 tritocerebral motor neurons, with 3 somata located in each tritocerebral lobe. Their axons cross the midline in a distinct commissure between the two muscles. The labral posterior retractor muscles, M3 and anterior dilator muscles of foregut, M38, are innervated from the ipsilateral tritocerebrum only. Both muscles together receive 8 motor axons and there are some common motor neurons that innervate both muscles. In addition, M2, M3 and M38 also receive common innervation from neurons located in the suboesophageal ganglion (SOG). In relation to the muscle, their somata are located on the ipsi- and the contralateral sides of the SOG. Their axons ascend through the circumoesophageal connectives and proceed into the frontal connectives without forming ramifications in the tritocerebral lobes. These axons also cross the midline in the periphery to reach muscles on both sides of the head. They either cross within the commissure between muscles M2, or through the frontal ganglion. Further more, electrophysiology of labral muscles in isolated insect heads was investigated by intracellular recordings from the fibers of individual muscles. The recordings showed that all postsynaptic potentials were excitatory and no inhibitory synaptic inputs to labral muscles were found during the present study. Similarly simultaneous intracellular recording from fibers of labral muscles and suboesophageal ganglion motor neurons also revealed no inhibitory synaptic inputs to labral muscles, and showed that suboesophageal neurons are common excitatory motor neurons. The innervation pattern was compared with that of the other body appendages of locust, and it was concluded that labral muscles are innervated from both sides of the CNS and their innervation pattern is bilaterally symmetric as that of other appendages. The participation of both tritocerebral and suboesophageal ganglion motor neurons supports the notion that the labrum is innervated by the so-called intercalary segment. The innervation pattern also supports the idea that the labrum derives from fused appendages: There are two symmetrical sets of motor neurons. Some of them cross the midline in the periphery. This indicates that during the evolution of the labrum its motor innervation pattern was reconfigured in the periphery, while the original bilateral sets of central neurons remained unchanged.

Comparative invertebrate neuroanatomy has seen a renaissance in recent years. Highly conserved neuroarchitectural traits offer a wealth of hitherto largely unexploited characters that can make valuable contributions in inferring phylogenetic relationships in cases where phylogenetic analyses of molecular or morphological data sets yield trees with conflicting or weakly supported topologies. Conversely, in those cases where robust phylogenetic trees exist, neuroanatomical features can be mapped onto the trees, helping to shed light on the evolution of the central nervous system. This thesis aims to provide detailed neuroanatomical data for a hitherto poorly studied invertebrate taxon, the segmented worms (Annelida). Drawing on the wealth of investigations into the architecture of the brain in different arthropods, the study focuses on the identification and description of possibly homologous brain centers (i.e. neuropils) in annelids. The thesis presents an extensive survey of the internal architecture of the brain of the ragworm Nereis diversicolor (Polychaeta, Annelida). Based upon confocal laser scanning microscope analyses, the distribution of neuroactive substances in the brain is described and the architecture of two major brain compartments, namely the paired mushroom bodies and the central optic neuropil, is characterized in detail. It is concluded that the central optic neuropil cannot be confidently homologized with similarly unpaired neuropils in the arthropod brain, but that annelid and arthropod mushroom bodies are probably homologues. This proposed homology is further explored by comparing 3D reconstructions of mushroom body neuropils and associated structures in the polychaete species Nereis diversicolor, Harmothoe areolata, and Lepidonotus clava with a 3D model of the mushroom bodies in the insect representative Leucophaea maderae. The neuropils are found to share a common principal organization and a similar neuroarchitectural integration. Lastly, the occurrence of unpaired midline neuropils, mushroom bodies, and associated structures is investigated in a broad taxonomic survey, including more than 20 representatives from major groups of the annelid radiation. Considerably complex brains, sometimes comprising mushroom bodies and other subcompartments, are only observed in errant polychaetes but not in sedentary polychaete species, nor in clitellates representatives. The implications of an assumed homology between annelid and arthropod mushroom bodies are discussed in light of the "new animal phylogeny". It is concluded that the homology of mushroom bodies in distantly related groups has to be interpreted as a plesiomorphy, pointing towards a considerably complex neuroarchitecture inherited from the last common ancestor, Urbilateria. Within the annelid radiation, the lack of mushroom bodies in certain groups is explained by wide-spread secondary reductions owing to selective pressures unfavorable for the differentiation of elaborate brains. Evolutionary trajectories of mushroom body neuropils in errant polychaetes remain enigmatic.

BGPI : équipe 6; Caractérisation d'espèces cryptiques du psylle Cacopsylla pruni, insecte vecteur d'une maladie des Prunus. Ecologie 2010, session " Adaptation des bioagresseurs de plantes à leur environnement biotique et abiotique "

Objectives: Workers in many industries are exposed to endotoxins, which may cause adverse health effects. In exposure assessment, information about exposure variability is essential. However, variability in exposure has rarely been investigated for biological agents and more specifically for endotoxin. Therefore, variance components and determinants of exposure were studied in a large database with >2000 endotoxin measurements. Methods: Data from 10 individual studies were combined to create a database with 2010 personal inhalable dust and endotoxin measurements, of which 1650 were repeated measurements. Exposure groups were defined based on job codes. Between- and within-worker variance components were estimated for different grouping strategies, and determinants of exposure were studied using mixed effects models. Results: Inhalable dust and endotoxin exposure levels are summarized for 46 industries and 4 broadly defined sectors. The between-worker variability exceeded the within-worker variability overall and within sectors and subsectors, and variance components were larger for endotoxin than for dust. Between-worker variability also exceeded within-worker variability in nearly half of the exposure groups based upon industries or job code within industries for endotoxin exposure and in 10% of the groups for dust exposure. Among other things, dustiness of the process, contact with animals, bulk production, presence of plant material or a cyclic process appeared as determinants of exposure, which largely explained the between-worker variability. Conclusions: Exposure groups were much less homogeneous for endotoxin exposure than for dust exposure. This is distinctly different than for chemical exposure. Large variability in measured exposure levels is inherent to endotoxin exposure, which is caused in part by determinants that influence growth of microorganisms. These findings have major consequences for the design of future occupational intervention and epidemiological studies. The measurement effort needs to be greater than exposure assessment for chemical agents which demonstrate lower exposure variability, especially when evaluating endotoxin exposure for compliance testing. The established determinants of exposure give direction for potential exposure control, although more information about determinants of day-to-day variability in exposure is still needed to be able to effectively control endotoxin exposure. © The Author 2008. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; International audience; New crop systems have been developed in the French West Indies that combine fallow or rotation crops with nematode-free vitro-plants to avoid the massive application of nematicides in banana fields. In these new banana fields, recontamination by the burrowing nematode Radopholus similis can then happen either by run-off or irrigation water. To understand these phenomena, we studied the vertical dissemination of R. similis by water leaching using soil cylinders and rainfall simulations. Steel drums were used to collect cylinders of soil (around 14.3 dm3) with a backhoe. The soil cylinders were placed in an aspersion chamber, saturated with water, and a R. similis suspension was placed on the soil surface. Afterwards, rainfalls ranging from 12 to 540 mm were simulated. Nematodes were then extracted from different soil layers (0–5 to 20–25 cm depth) using either (i) a Seinhorst elutriator followed by a Baermann funnel or (ii) centrifugation–flotation combined with Meldola blue staining. Results showed that dissemination of R. similis at the scale of the decimetre in nitisoil is limited: less than 8% of the applied nematodes reached layers deeper than 10 cm after exceptional rainfalls that represent several times the poral volume of the soil. Dissemination below 25 cm depth seemed to be limited to very few individuals, from 0.1 to 0.2%. Among leached nematodes, the percentage of non-active and dead nematodes increased significantly with depth. It seems that R. similis have developed a behaviour to escape leaching. These findings question the generally accepted idea that water dissemination of plant-parasitic nematodes is mainly a passive phenomenon.

cum laude graduation (with distinction)

cum laude graduation (with distinction)

cum laude graduation (with distinction)

cum laude graduation (with distinction)

Identification and characterisation of the circadian pacemaker of the cockroach Leucophaea maderae, Identifizierung und Charakterisierung des circadianen Schrittmachers der Schabe Leucophaea maderae

Lake Tana is by far the largest lake of Ethiopia and source of the Blue Nile. By feeding on zooplankton, small barbs (< 10 cm) occupy a central position in Lake Tana's ecosystem. Catching them could release pressure on the overexploited, unique species flock of large barbs (up to 100 cm). Aiming at small barbs, we need first to assess its possible impact on the food web and productivity. To advise on sustainable management, the biology and ecology of the small Barbus species in Lake Tana was investigated: identification, feeding biology and major food source (i.e. zooplankton) in the environment, their reproductive biology, individual growth and productivity. Three valid small Barbus species ( Barbus humilis , B. pleurogramma and B. tanapelagius ) were identified in Lake Tana. Barbus tanapelagius is discovered in this study and it is endemic to Lake Tana. Barbus humilis and B. tanapelagius are the most abundant small barbs and will have a central role in energy and biomass transfer in the food web of the lake.Resource partitioning with competitors (juveniles of the large barbs and a zooplanktivorous larger barb, Barbus brevicephalus ) involve space and food . Habitat use differed along the littoral-pelagic gradient. Barbus pleurogramma , B. humilis and juvenile 'large barbs' preferred the littoral shallow habitats, whereas B. tanapelagius and B. brevicephalus predominantly occupied sublittoral and pelagic habitats. This high degree of habitat segregation between the juveniles of the commercially important 'large barbs' and the 'small barb' B. tanapelagius opens perspectives for a subsidiary small-meshed fishery for small barbs in the pelagic habitat. The information generated in this study pertaining to the resource partitioning, interaction between small barbs and juvenile large barbs, reproduction, growth, mortality and the production of small barbs is used to discuss the potential to start subsidiary small-meshed fishery on the small barbs and its consequences on the existing fishery and fish community. The annual maximum sustainable yield of B. tanapelagius was 4,000 ton (fourfold of the current annual fish catch from the lake). Recommendations to start subsidiary small-meshed fishery only for B. tanapelagius at the pelagic habitat based on the annual maximum sustainable yield and production potential (annual P/B ratio) is given.

The 15 Barbus species of Lake Tana, a large shallow lake located at an altitude of 1830 m in the north-western highlands of Ethiopia, form the only remaining intact species flock of large (max. 100cm) cyprinid fishes. Lake Tana is the source of the Blue Nile and high waterfalls (40 m) at Tissisat ('smoking water'), 30 km downstream from the outflow, effectively isolate the lake's ichtyofauna from the lower Nile basin.Lake Tana and its endemic Barbus species flock form a natural laboratory and provide an unique opportunity to study the selective forces driving speciation and diversity in freshwater fish communities. Lake Tana's Barbus species flock was investigated from molecules to populations.The rapid ecological diversification and speciation of Lake Tana's Barbus is at least as spectacular as the adaptive radiation of the cichlids in East-Africa's Rift Valley Lakes (Victoria, Malawi and Tanganyika). One of the most intriguing aspects of these Barbus is the large number (8) of piscivores. Cyprinid fishes are not well designed for piscivory. Furthermore, one of the key innovations in the bodyplan of the evolutionary successful cyprinid fishes (>2000 species), the voluminous palatal organ lining the pharynx, turned out to have come at a cost: their reduced competitive abilities to function as piscivores. However, Lake Tana lacks potential piscivorous competitors, rendering the piscivorous Barbus by far the "best" and apparently highly successful. They have adapted to all available macro-habitats, using different techniques, a unique scenario for barbs.The lack of fisheries legislation and regulations after the introduction of a small-scale commercial gillnet fishery in Lake Tana towards the end of the 1980s, resulted in the rapid and dramatic decline (75%) of Barbus during the 1990s. The gillnet fisheries mainly targets the spawning aggregations of the barbs (recruitment-overfishing) and is now threatening the existence of this remarkable species flock.

Lake Tana is by far the largest lake of Ethiopia and source of the Blue Nile. By feeding on zooplankton, small barbs (< 10 cm) occupy a central position in Lake Tana's ecosystem. Catching them could release pressure on the overexploited, unique species flock of large barbs (up to 100 cm). Aiming at small barbs, we need first to assess its possible impact on the food web and productivity. To advise on sustainable management, the biology and ecology of the small Barbus species in Lake Tana was investigated: identification, feeding biology and major food source (i.e. zooplankton) in the environment, their reproductive biology, individual growth and productivity. Three valid small Barbus species ( Barbus humilis , B. pleurogramma and B. tanapelagius ) were identified in Lake Tana. Barbus tanapelagius is discovered in this study and it is endemic to Lake Tana. Barbus humilis and B. tanapelagius are the most abundant small barbs and will have a central role in energy and biomass transfer in the food web of the lake.Resource partitioning with competitors (juveniles of the large barbs and a zooplanktivorous larger barb, Barbus brevicephalus ) involve space and food . Habitat use differed along the littoral-pelagic gradient. Barbus pleurogramma , B. humilis and juvenile 'large barbs' preferred the littoral shallow habitats, whereas B. tanapelagius and B. brevicephalus predominantly occupied sublittoral and pelagic habitats. This high degree of habitat segregation between the juveniles of the commercially important 'large barbs' and the 'small barb' B. tanapelagius opens perspectives for a subsidiary small-meshed fishery for small barbs in the pelagic habitat. The information generated in this study pertaining to the resource partitioning, interaction between small barbs and juvenile large barbs, reproduction, growth, mortality and the production of small barbs is used to discuss the potential to start subsidiary small-meshed fishery on the small barbs and its consequences on the existing fishery and fish community. The annual maximum sustainable yield of B. tanapelagius was 4,000 ton (fourfold of the current annual fish catch from the lake). Recommendations to start subsidiary small-meshed fishery only for B. tanapelagius at the pelagic habitat based on the annual maximum sustainable yield and production potential (annual P/B ratio) is given.

The 15 Barbus species of Lake Tana, a large shallow lake located at an altitude of 1830 m in the north-western highlands of Ethiopia, form the only remaining intact species flock of large (max. 100cm) cyprinid fishes. Lake Tana is the source of the Blue Nile and high waterfalls (40 m) at Tissisat ('smoking water'), 30 km downstream from the outflow, effectively isolate the lake's ichtyofauna from the lower Nile basin.Lake Tana and its endemic Barbus species flock form a natural laboratory and provide an unique opportunity to study the selective forces driving speciation and diversity in freshwater fish communities. Lake Tana's Barbus species flock was investigated from molecules to populations.The rapid ecological diversification and speciation of Lake Tana's Barbus is at least as spectacular as the adaptive radiation of the cichlids in East-Africa's Rift Valley Lakes (Victoria, Malawi and Tanganyika). One of the most intriguing aspects of these Barbus is the large number (8) of piscivores. Cyprinid fishes are not well designed for piscivory. Furthermore, one of the key innovations in the bodyplan of the evolutionary successful cyprinid fishes (>2000 species), the voluminous palatal organ lining the pharynx, turned out to have come at a cost: their reduced competitive abilities to function as piscivores. However, Lake Tana lacks potential piscivorous competitors, rendering the piscivorous Barbus by far the "best" and apparently highly successful. They have adapted to all available macro-habitats, using different techniques, a unique scenario for barbs.The lack of fisheries legislation and regulations after the introduction of a small-scale commercial gillnet fishery in Lake Tana towards the end of the 1980s, resulted in the rapid and dramatic decline (75%) of Barbus during the 1990s. The gillnet fisheries mainly targets the spawning aggregations of the barbs (recruitment-overfishing) and is now threatening the existence of this remarkable species flock.

The decrease in stratospheric ozone concentration has received wide attention because the ozone layer protects the earth from harmful ultraviolet-B radiation (UVB, 280-320 nm). UVB radiation is harmful for organisms, and therefore scientific research into how UVB radiation affects organisms and ecosystems receives great interest. This thesis describes the effects of UVB radiation on interactions between phytoplankton (algae) and zooplankton (waterfleas) in freshwater ecosystems.The underlying hypothesis in this thesis is that phytoplankton is directly affected by UVB radiation because it needs visible light (PAR, 400-700 nm) for photosynthesis, and is consequently also exposed to UVB. Zooplankton on the other hand is not dependent on light, and is able to move actively through the water. This capability of vertical migration, and the possible ability to detect UV radiation may allow zooplankters to regulate their exposure to UVB. Therefore, indirect effects on zooplankton through changes in phytoplankton (its food) may play a more important role than direct UVB effects.UVB, UVA (320-400 nm) and PAR radiation were measured in 19 aquatic systems in the Netherlands. In most systems the penetration of UVB radiation was limited to the upper decimetres. High phytoplankton biomass or high concentrations of humic acids caused the limited light penetration. Lake Maarsseveen was the clearest system in this study with a vertical attenuation coefficient (K d ) for UVB of 9.1 (m -1). This corresponded to a 1% UVB penetration depth of 51 cm. The effect of UVB radiation on a system will be a combination of penetration depth, mixing processes, and depth of the system.There is a number of UV-mediated qualitative changes in phytoplankton that may affect herbivorous zooplankton. Changes in phytoplankton species composition, increase in cell size and increase in cell wall thickness will negatively affect ingestion and digestion by zooplankton. Phytoplankton cell biochemistry is also affected by UVB radiation, namely a decrease in lipids and proteins, and an increase in carbohydrates. This will strongly influence the cells nutrient quality. The potential negative effect of UV on fatty acids (FA) in phytoplankton call for special attention. FA play a major role in nutrition for most animals, and as such UV-mediated lipid peroxidation or reduced biosynthesis of essential FA could be a major determinant of food quality for aquatic herbivores.Experiments with zooplankton grazing on UVB-stressed phytoplankton showed varying effects on grazing rates. Grazing rates of the large waterflea Daphnia were not affected by UVB-stressed phytoplankton. The small waterflea Bosmina and small rotifer Brachionus had both increased and decreased grazing rates on UVB-stressed phytoplankton. These experiments suggest that possible effects of enhanced UVB radiation on phytoplankton-zooplankton interactions are not straightforward predictable from grazing experiments. Moreover, extrapolation of data to predict ecosystem response to UVB stress seems unjustified.Life history experiments with Daphnia feeding on several species of UVB-stressed phytoplankton showed that life history traits were negatively affected. Effects of UVB-stressed phytoplankton on the population growth rate of Daphnia were not significant. Effects on clutch sizes and quality of offspring were significant. In general, a smaller number of juveniles of poorer quality was produced in the UVB treatments. This may have implications for the food web functioning. The UVB effect was dependent on the phytoplankton species. The UVB effects may be caused by a change in food quality combined with possible reduced digestibility of UVB stressed phytoplankton.No UVB effects were found in the experiments with indoor model ecosystems. UVB radiation had no significant effect on the phytoplankton, zooplankton, periphyton or macro-invertebrate communities in these model ecosystems. A bio-assay with Daphnia feeding on phytoplankton from the model ecosystems showed that phytoplankton from the UVB treatments had a negative effect on Daphnia growth and survival, and to a lesser extent on fecundity. These results indicate that the transfer of energy from phytoplankton to zooplankton can be negatively influenced by UVB radiation. Overall, the model ecosystems were not affected by the UVB stress. From these results it can be concluded that a natural ecosystem with similar penetration of UVB can be resistant to UVB radiation presently occurring at temperate latitude.Field experiments at 3 different latitudes (in the Netherlands, Norway and Spitsbergen) showed that present levels of UVB radiation may negatively affect phytoplankton and zooplankton. The different phytoplankton species showed different responses in growth rate to UVB, UVA and PAR radiation. This implies that increased levels of UVB radiation could lead to shifts in phytoplankton community structure. Chlamydomonas (a green algae with flagella) responded to UVB radiation with a loss of flagella, whereas the growth rate was not affected.Daphnia in Lake Zwemlust (the Netherlands) responded to UVB with a decreased grazing rate and smaller body size, whereas the survival was not affected. Daphnia grazing rates were affected in all three locations, though variance was large and differences marginal. This shows that solar UVB radiation in potential can reduce the transfer of energy from phytoplankton to zooplankton. UVB effects were comparable between the three locations. The magnitude of the UVB effects was quite different, due to very different weather conditions.A field study was done in the province of Saskatchewan, Canada, comparing seston (suspended live and dead particles) quantity and quality of ponds and lakes with different light penetration properties. Multivariate analysis suggested that the phytoplankton species composition was influenced by the light climate of the studied system. A standardized laboratory experiment with Daphnia showed that the phospholipid content of the seston was the best predictor of Daphnia growth, because of the high nutritional value of phospholipids. It was hypothesized that in the studied systems, light climate and especially the penetration of ultraviolet radiation was important in determining the phospholipid content of the seston. The proposed relationships between light climate, phospholipid content of the seston, and Daphnia growth need experimental confirmation.Summarizing the different experiments described in this thesis, the effects of UVB on the phytoplankton-zooplankton interactions were present, detectable, and mostly negative. The magnitude of the UVB effects was not large. It was not possible to make generalizations because of the species-specific reactions to UVB. The experiments were all short-term, and it may be erroneous to make long-term predictions based on these results. However, the subtle differences found in this study may be important in determining ecosystem functioning. UVB radiation interacts with other environmental variables (such as temperature, nutrient concentrations, and vertical mixing), and is already playing a role in the functioning of an ecosystem.See also:project descriptionandc.v. of the author.