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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Evolutionary Genetics of Barramundi (Lates Calcarifer)in the Australian Region

cmarshall@tobob.com, Carina Rynn Ecremen Marshall January 2005 (has links)
Barramundi (Lates calcarifer) is a centropomid teleost with a wide distribution across the Indo Pacific. In Australia, barramundi are native to the tropical zone from Exmouth Gulf in Western Australia, across the northern part of the continent, to the Mary River in Queensland. Barramundi are protandrous hermaphrodites, and are euryhaline, with a catadromous life history. Barramundi are a valuable Australian resource, with important commercial and recreational fisheries and aquaculture production to the value of $11 million dollars per year. Recent declines in the availability of the fish in some rivers has led to an interest in the possibility of restocking rivers with barramundi from other areas. Determining the genetic structure of barramundi populations in Australia is important for understanding biogeographic history, and appropriate management practices for both aquaculture and recreational and commercial fishing. Previous studies have concentrated on the east coast of Australia, and have largely ignored the western populations. In this study, I obtained DNA data from barramundi populations across the Australian range of the species, as well as populations from Papua New Guinea and Indonesia. The aims of this study were to use the genetic data to determine: 1. if populations in Western Australia show genetic differences between geographic regions 2. if these populations show an ancestral split from populations in the east of Australia and 3. the ancestral origins of Australian barramundi. Previous studies of DNA data from barramundi have discovered an east/west split occurring at the Torres Strait that was assumed to be caused by the closing of the strait during lowered sea levels. However, these studies suffered from a bias in sampling area, concentrating either on the eastern half of the range of barramundi, or on the western tip of the range. Data from these studies were combined and reanalyzed. Two major clades were discovered, with considerable biogeographic structuring, but their geographic locations did not coincide with the reported vicariance event at the Torres Strait. Instead, historical divisions among freshwater drainage systems appeared to have driven the evolutionary history of barramundi in Australia. In order to investigate these historical divisions further, a 290 bp section of the mitochondrial DNA control region was sequenced in 284 barramundi from seven populations across the Australian geographic range of the species and from one population in Papua New Guinea and one population in Indonesia. Analyses of molecular variance within and among populations showed significant geographic structuring, based on biogeographical provinces and drainage divisions. Nested clade analyses indicated that these geographical associations were the result of restricted gene flow, range expansion, and past fragmentation events. I hypothesise that the Ord River area in the west of the continent was the ancestral source population for the rest of the species’ range across Australia, with Indonesia being the most likely origin of this source. Populations of barramundi from the Pilbara region are genetically distinct and geographically isolated, with strong evidence of an ancestral divide along geographical barriers to dispersal. There is a strong association between Papua New Guinea and Australia, although further investigations using the cytochrome b region of mitochondrial DNA indicated a more ancestral divide between the two than is currently evident, which could reflect an ancient geographical divide between the two, or could be evidence of a secondary migration route to Australia. For a more detailed study of evolutionary processes acting on populations of barramundi in Western Australia, allelic diversity was examined at five microsatellite loci. All loci were polymorphic and genotypic frequencies conformed to Hardy-Weinberg expectations, with no significant linkage between loci evident in any population. Measures of within population diversity were significantly related to latitude, suggesting southerly migration from a northern source population. The Ord River was the most genetically diverse population, and the most likely ancestral migration source to the area, with diversity decreasing down the west coast. Although there were significant differences among populations, the nuclear microsatellite data do not indicate the same degree of genetic structuring as is evident in the mitochondrial data. This may be a consequence of rapid evolutionary change at microsatellite loci, with past separations or population differences masked by recombination and back mutation of the microsatellite alleles. However, the nature of nuclear and mitochondrial inheritance may also indicate life history differences between the sexes, where significant genetic contribution to gene flow by males and limited female gene flow may lead to preservation of maternally inherited population substructure. The principal findings from this study are: • There is no genetic evidence for an east/west division of barramundi populations in Australia, as suggested by previous research. • Despite barramundi’s catadromous life history, and ability to disperse through marine waters, the present genetic structure indicates a division principally among river drainages. From a population genetic viewpoint, the species can be regarded as freshwater, rather than marine. • The most likely origin of barramundi in Australia is the Ord River region, with Indonesia as the route of migration. • Differences in the population structure demonstrated by nuclear and mitochondrial data indicate possible life history differences between the sexes. • Barramundi populations in different biogeographical provinces may have been substantially isolated over a long period of time, and may therefore represent independently evolving populations. This has important implications for fishery management and translocation issues for restocking rivers.
2

PCR-RFLP analys av mt-DNA hos Öring (Salmo trutta) i Gävleborgs län.

Björkbom, Tommy January 2010 (has links)
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3

PCR-RFLP analys av mt-DNA hos Öring (Salmo trutta) i Gävleborgs län.

Björkbom, Tommy January 2010 (has links)

4

Využití mikrosatelitních markerů pro studium populační struktury jelenovitých v západních Karpatech

Gřundělová, Alžběta January 2019 (has links)
The aim of this work was to analyze nuclear microsatellite markers, which were processed by methods of landscape genetics and then compared with mitochondrial sequences (mtDNA) from previous research. Microsatellite analysis was performed using 11 microsatellite sequences with a total of 188 alleles. A total of 94 individuals were analyzed, divided into 3 subpopulations. The average expected heterozygosity of 0.82 and the average observed heterozygosity of the whole population was 0.72. There is a gene flow between the subpopulations. Transport infrastructure affects the flow of genes to a small extent.
5

Revisão taxonômica das espécies sulamericanas de ermitões do gênero Pagurus Fabricius, 1775 (Anomura: Paguridae): análises morfológicas e moleculares / Taxonomic review of South American species of hermit crabs of the genus Pagurus Fabricius, 1775 (Anomura:Paguridae): morphological and molecular analysis

Campillay, Nicole Alice Olguín 16 April 2012 (has links)
O gênero Pagurus é um táxon heterogêneo de ermitões, com ampla distribuição mundial, descrito há mais de duzentos anos. A sistemática do grupo é complexa com uma longa história de rearranjos taxonômicos. A classificação conta com a inclusão de numerosas novas espécies e separação de algumas inicialmente contidas no táxon estabelecendo-se novos gêneros. Devido à extensa distribuição das espécies que compõem o táxon, foi necessário restringir o objetivo deste estudo. Assim foi avaliado o status taxonômico das espécies que ocorrem nas costas Pacífica e Atlântica da América do Sul, por meio da combinação de análises morfológicas e moleculares das espécies, utilizando dois marcadores genéticos (16S rDNA e Histona 3). As análises taxonômicas mostraram uma alta variabilidade morfológica nas 22 espécies examinadas. As espécies se encaixam perfeitamente em quatro dos onze grupos preestabelecidos dentro de Pagurus. Além disso, foram fornecidos os caracteres morfológicos que definem um desses grupos. Adicionalmente foi incluída uma chave para ajudar na identificação de todas as espécies. As análises independentes dos dados moleculares mostraram resultados contrastantes. O gene mitocondrial foi mais variável e portanto mais informativo, proporcionando uma hipótese mais clara das relações internas entre os membros de Pagurus. Assim, as topologias moleculares resultantes, concordaram em vários aspectos com o reportado nos dados morfológicos das espécies. De modo que, as semelhanças morfológicas foram refletidas na formação dos nós internos. Assim, as análises do gene 16S e H3 mostraram-se concordante com a morfologia, refletindo-se na formação de alguns dos grupos previamente propostos. Como ponto importante, ressalta-se a separação das espécies que compõe o grupo provenzanoi como um táxon diferenciado dentro de Pagurus. Ao mesmo tempo, as análises com o gene H3 mostraram a espécie Propagurus gaudichaudii inserida dentro de Pagurus, questionando a validade taxonômica de Propagurus. Como só foi incluída uma das cinco espécies do gênero, é claramente necessário a inclusão de outras espécies contidas neste táxon, bem como alguns outros genes uma revisão das espécies contidas neste táxon, junto com análises de outros genes, a fim de resolver definitivamente o status taxonômico de Propagurus. / The genus Pagurus is a heterogeneous taxon of hermit crabs, with worldwide distribution which was described more than two hundred years ago. Systematics of the group is complex and with a long history of taxonomic rearrangements. Thus current classification accounts for inclusion of many new species and splitting-off of some of the original species in order to establish new genera. Because of the extensive distribution of the species that conform this taxon it was necessary to restrict the aim of this study. Thus I evaluated the taxonomic status of the species found in the Pacific and Atlantic coasts of South America using a combination of both morphologic and molecular analyses (16S rDNA and Histona 3). The taxonomic analysis showed high morphological variation among all the 21 examined species. The analyzed species seemed to perfectly fit four out of the eleven morphologically pre-established groups of Pagurus. Furthermore I provide morphological characters that define one of these groups. Additionally, I included a key to aid in the identification of all the target species. Independent analysis of the molecular data showed contrasting results. The mitochondrial gene was the most variable and thus the most informative, providing a clearer hypothesis of the internal relationships among members of Pagurus. Therefore, both 16S and H3 analyses were in general agreement with the morphology. Thus, the resultant molecularly based topologies reflected some of the groups previously proposed. It is important to point out that all the included species belonging to the provenzanoi group were clustered together separated from other clades within Pagurus. At the same time, the analysis with the gen H3 showed Propagurus gaudichaudii clustered within Pagurus, thus questioning the taxonomic validity of Propagurus. As I only included one of the five species of the genus, it is obviously necessary to include other the species contained in this taxon, as well as some other genes in order to definitely solve the taxonomic status of Propagurus.
6

Γενετική ποικιλότητα και φυλογενετικές σχέσεις "λιμναίων" και "θαλάσσιων" πληθυσμών της Atherina boyeri

Κράιτσεκ, Σπυριδούλα 02 December 2008 (has links)
Στην εργασία αυτή μελετήθηκε η γενετική δομή και οι φυλογενετικές σχέσεις μεταξύ έξι πληθυσμών της Atherina boyeri που προέρχονταν από τις περιοχές της Μυτιλήνης, της Νισύρου, της Κάσου, της Κύμης, και των λιμνών της Βιστωνίδας και Iznik (στην Τουρκία). Συγκεκριμένα, έγινε μελέτη των περιοριστικών θραυσμάτων ποικίλου μήκους (RFLP analysis) των τμημάτων 12S rRNA, 16S rRNA και του βρόγχου εκτόπισης (D-loop) του μιτοχονδριακού DNA. Τα αποτελέσματα αυτά συνδυάστηκαν με τα αποτελέσματα άλλων μελετών που αφορούσαν εννέα διαφορετικές περιοχές της Ελλάδας (Κάλυμνο, Κεφαλλονιά, Αμβρακικός, Κως, Λήμνος, Εύβοια, Ζάκυνθος, Λευκάδα και Κουρνά-Κρήτη) και είχαν γίνει στο εργαστήριο. Από την RFLP ανάλυση αποκαλύφθηκαν 23 διαφορετικοί σύνθετοι απλότυποι. Βάσει των αποτελεσμάτων γίνεται σαφής διαχωρισμός μεταξύ «λιμναίου» και «θαλάσσιου» τύπου πληθυσμών. Οι πληθυσμοί από τις λίμνες/λιμνοθάλασσες (Βιστωνίδα, Κουρνά, Κούταβος/Κεφαλλονιά, Αμβρακικός, Iznik/Τουρκία ), καθώς και από περιοχές που επικρατούν παρόμοιες συνθήκες (Κύμη, Βαθύ Καλύμνου), έχουν τους απλότυπους 1-6, ενώ οι «θαλάσσιου» τύπου πληθυσμοί (Κως, Λήμνος, Εύβοια, Μυτιλήνη, Νίσυρος, Κάσος, Ζάκυνθος, Λευκάδα) έχουν τους απλότυπους 7-23. Διαπιστώθηκε επίσης η ύπαρξη πέντε διαγνωστικών προτύπων μεταξύ «λιμναίων» και «θαλάσσιων» πληθυσμών. Επιπλέον, παρατηρήθηκε η ύπαρξη ενός διαγνωστικού προτύπου για τους πληθυσμούς από την Κω, τη Λήμνο και τη Νίσυρο, βάσει του οποίου μπορούμε να διαχωρίσουμε τους πληθυσμούς αυτούς από τους υπόλοιπους θαλάσσιους πληθυσμούς που μελετήθηκαν, καθώς και ένα διαγνωστικό πρότυπο βάσει του οποίου μπορούμε να διακρίνουμε τον πληθυσμό της Νισύρου από τους υπόλοιπους επτά πληθυσμούς «θαλάσσιου» τύπου. Με βάση τα δεδομένα αυτά υπολογίστηκε η καθαρή νουκλεοτιδική απόκλιση μεταξύ των πληθυσμών και βρέθηκε να είναι αρκετά υψηλή σε ορισμένες περιπτώσεις. Τα παραπάνω αποτελέσματα επιβεβαιώνονται και από τα δύο φυλογενετικά δένδρα που κατασκευάστηκαν με τις μεθόδους UPGMA και Μέγιστης Φειδωλότητας. Βάσει της τιμής του Nst (50%) που υπολογίστηκε μόνο η μισή από την ολική γενετική ποικιλότητα που παρατηρήθηκε οφείλεται σε διαφορές ανάμεσα στους πληθυσμούς, ενώ η υπόλοιπη οφείλεται σε ενδοπληθυσμιακές διαφορές. / Τhe genetic differentiation and the phylogenetic relationships of six greek populations of Atherina boyeri were investigated at the mitochondrial level. The samples originated from the marine sites of Lesvos, Nisyros, Kasos, Kymi and the lakes Vistonida and Iznik (Turkey). RFLP analysis of three mtDNA segments (12S rRNA, 16S rRNA and D-loop) amplified by PCR were used. These results were combined with others available in the laboratory, concerning nine more greek populations (Kalymnos, Kefallonia, Amvrakikos, Kos, Limnos, Evvoia, Zakynthos, Leukada, Kourna/Crete). Twenty-three composite haplotypes where revealed from the RFLP analysis. There is a clear distinction between “marine” and “lagoon” type populations. In particular, the populations from the lakes/lagoons (Vistonida, Kourna, Kefallonia, Amvrakikos, Iznik), as well as the populations from sites with similar environmental conditions to the lakes/lagoons (Kymi, Kalymnos) have the haplotypes 1-6, while the “marine” type populations (Kos, Limnos, Evvoia, Lesvos, Nisyros, Kasos, Zakynthos, Leukada) have the haplotypes 7-23. Five specific restriction patterns were also revealed, which can be used to distinguish the “marine” from the “lagoon” type populations. Moreover, one diagnostic pattern, with which we can distinguish the populations from Kos, Limnos and Nisyros from the rest “marine” type populations studied, was revealed, as well as it was revealed one diagnostic pattern, with which we can distinguish the population of Nisyros from the rest “marine” type populations. The genetic divergence values estimated among “lagoon” and “marine” type populations were high, with the populations from Evvoia and Kourna to show the greatest divergence (10.450%) and the populations from Amvrakikos and Nisyros the lowest (5.549%). The above results were also confirmed and by the two phylogenetic trees that were conducted using the UPGMA and the Maximum Parsimony methods. The trees consist of two main clades, which contain the “marine” and “lagoon” populations respectively. Our results show that distinct “lagoon” populations (such as from Vistonida and Kourna) have similar genetic structure, a situation that is not true for the “marine” populations, since there are populations with completely different genetic structure. Finally, the Nst value (50%) indicates that half of the overall genetic diversity detected was between populations.
7

Revisão taxonômica das espécies sulamericanas de ermitões do gênero Pagurus Fabricius, 1775 (Anomura: Paguridae): análises morfológicas e moleculares / Taxonomic review of South American species of hermit crabs of the genus Pagurus Fabricius, 1775 (Anomura:Paguridae): morphological and molecular analysis

Nicole Alice Olguín Campillay 16 April 2012 (has links)
O gênero Pagurus é um táxon heterogêneo de ermitões, com ampla distribuição mundial, descrito há mais de duzentos anos. A sistemática do grupo é complexa com uma longa história de rearranjos taxonômicos. A classificação conta com a inclusão de numerosas novas espécies e separação de algumas inicialmente contidas no táxon estabelecendo-se novos gêneros. Devido à extensa distribuição das espécies que compõem o táxon, foi necessário restringir o objetivo deste estudo. Assim foi avaliado o status taxonômico das espécies que ocorrem nas costas Pacífica e Atlântica da América do Sul, por meio da combinação de análises morfológicas e moleculares das espécies, utilizando dois marcadores genéticos (16S rDNA e Histona 3). As análises taxonômicas mostraram uma alta variabilidade morfológica nas 22 espécies examinadas. As espécies se encaixam perfeitamente em quatro dos onze grupos preestabelecidos dentro de Pagurus. Além disso, foram fornecidos os caracteres morfológicos que definem um desses grupos. Adicionalmente foi incluída uma chave para ajudar na identificação de todas as espécies. As análises independentes dos dados moleculares mostraram resultados contrastantes. O gene mitocondrial foi mais variável e portanto mais informativo, proporcionando uma hipótese mais clara das relações internas entre os membros de Pagurus. Assim, as topologias moleculares resultantes, concordaram em vários aspectos com o reportado nos dados morfológicos das espécies. De modo que, as semelhanças morfológicas foram refletidas na formação dos nós internos. Assim, as análises do gene 16S e H3 mostraram-se concordante com a morfologia, refletindo-se na formação de alguns dos grupos previamente propostos. Como ponto importante, ressalta-se a separação das espécies que compõe o grupo provenzanoi como um táxon diferenciado dentro de Pagurus. Ao mesmo tempo, as análises com o gene H3 mostraram a espécie Propagurus gaudichaudii inserida dentro de Pagurus, questionando a validade taxonômica de Propagurus. Como só foi incluída uma das cinco espécies do gênero, é claramente necessário a inclusão de outras espécies contidas neste táxon, bem como alguns outros genes uma revisão das espécies contidas neste táxon, junto com análises de outros genes, a fim de resolver definitivamente o status taxonômico de Propagurus. / The genus Pagurus is a heterogeneous taxon of hermit crabs, with worldwide distribution which was described more than two hundred years ago. Systematics of the group is complex and with a long history of taxonomic rearrangements. Thus current classification accounts for inclusion of many new species and splitting-off of some of the original species in order to establish new genera. Because of the extensive distribution of the species that conform this taxon it was necessary to restrict the aim of this study. Thus I evaluated the taxonomic status of the species found in the Pacific and Atlantic coasts of South America using a combination of both morphologic and molecular analyses (16S rDNA and Histona 3). The taxonomic analysis showed high morphological variation among all the 21 examined species. The analyzed species seemed to perfectly fit four out of the eleven morphologically pre-established groups of Pagurus. Furthermore I provide morphological characters that define one of these groups. Additionally, I included a key to aid in the identification of all the target species. Independent analysis of the molecular data showed contrasting results. The mitochondrial gene was the most variable and thus the most informative, providing a clearer hypothesis of the internal relationships among members of Pagurus. Therefore, both 16S and H3 analyses were in general agreement with the morphology. Thus, the resultant molecularly based topologies reflected some of the groups previously proposed. It is important to point out that all the included species belonging to the provenzanoi group were clustered together separated from other clades within Pagurus. At the same time, the analysis with the gen H3 showed Propagurus gaudichaudii clustered within Pagurus, thus questioning the taxonomic validity of Propagurus. As I only included one of the five species of the genus, it is obviously necessary to include other the species contained in this taxon, as well as some other genes in order to definitely solve the taxonomic status of Propagurus.
8

Testing the effectiveness of the mt DNA Cytochrome c oxidase subunit 1 (COI) gene locus for identifying species of Polychaete worm (Polychaeta: Annelida) in New Zealand

Brett, Christy Donna January 2006 (has links)
The ability to accurately identify species is fundamental to ecological research and environmental monitoring. Current taxonomic identifications often rely on differentiation of morphologically ambiguous characters, and a process of categorization which is tedious and often leads to misidentifications. This is compounded by the presence of cryptic taxa, which may be prevalent among Polychaete worms (Polychaeta: Annelida). With increased access to genetic techniques, Cytochrome c oxidase subunit I has been suggested as a possible aid to assist in the discrimination of species resources. In this study, I tested the hypothesis that the mtDNA COI gene locus is effective in discriminating morphologically recognised species of Polychaete worms. A 543 base-pair fragment of the COI locus was successfully extracted for 111 individuals from 16 out of 20 morphologically recognised species. Average intraspecific divergences were 0.8 %, ranging from 0 % to 5 %. Average interspecific variation was 26.4 %, ranging from 13.8 % to 36.8 %. The lowest divergences were found between two Nereid species (13.8 %), and two Glycera americana species (17.2 %). Relatively high maximum divergences of over 30 % suggest that some species may have reached a divergence saturation level, which may partially explain why familial groupings in constructed trees were not monophyletic. Divergences within the different Nereid species - a group previously known to have morphologically cryptic species - did not reveal the presence of any cryptic taxa. Pairwise comparisons showed a clear divide between percentages of intra- and interspecific divergences, and the suggested threshold of 11 % is effective for the taxa investigated here. On the basis of these results, I conclude that sequence variation in the mtDNA COI gene locus is effective in discriminating morphologically recognised species of Polychaete worms, but may not be appropriate for deeper (e.g. generic or familial) phylogenetic relationships among taxa.
9

L’abeille noire et la ruche-tronc : approche pluridisciplinaire de l’apiculture traditionnelle cévenole : histoire, diversité et enjeux conservatoires / Black bee and log hive : Multidisciplinary approach of traditional beekeeping in Cévennes : History, diversity, and conservation issues

Lehébel-Péron, Ameline 18 December 2014 (has links)
Les Cévennes sont depuis des siècles connues pour être des « terres de miel ». L'apiculture y est caractérisée par lo brusc, une ruche traditionnelle construite avec un tronc de châtaignier évidé, couvert d'une lauze de schiste. Les ruchers-troncs constituent une forme d'apiculture très ancienne et rustique, qui a contribué à l'histoire de l'occupation humaine et à la dynamique des paysages en Cévennes. Les ruches étaient à l'origine exclusivement sédentaires et peuplées d'abeilles noires (Apis mellifera mellifera), présentes en Cévennes bien avant l'arrivée des humains. Aujourd'hui, l'apiculture cévenole se fait principalement en ruches à cadres. Les pratiques apicoles actuelles — achat d'abeilles, transhumance, sélection, etc.— ont conduit à la diminution des populations de sous-espèces d'abeilles locales et à leur homogénéisation génétique. Afin de mieux connaître et de préserver ce patrimoine apicole naturel et culturel exceptionnel, le Parc national des Cévennes a initié cette étude pluridisciplinaire à travers le financement d'une thèse CIFRE. Ce travail est composé de trois parties.(I) L'objet de la première partie est l'habitat, la ruche. Les documents d'archives permettent d'affirmer que les ruches-troncs sont apparues en Cévennes à la fin du Moyen Âge, puis se sont développées et maintenues jusqu'à la première moitié du XXe siècle. Le passage de la ruche-tronc à la ruche à cadres moderne s'est réalisé progressivement au cours du siècle dernier. Les témoignages des anciens Cévenols ont permis d'appréhender les pratiques, les savoirs et les savoir-faire associés à ces ruchers traditionnels. Enfin, le micro-environnement des ruchers a été caractérisé grâce à des analyses spatiales qui viennent corroborer le discours local sur l'emplacement idéal d'un rucher.(II) L'abeille noire est au cœur de la deuxième partie. De l'abeille commune à l'abeille « noire agressive », les considérations du milieu apicole sur l'abeille locale ont évolué au cours du siècle écoulé. Un état des lieux de la population d'abeilles a été réalisé en utilisant la morphométrie géométrique, puis l'ADN mitochondrial. La morphométrie permet de dire que les 2/3 de la population d'abeilles des Causses et des Cévennes sont constitués d'abeilles noires. L'étude de l'ADN mitochondrial nous alerte néanmoins sur le taux élevé d'introgression dans ces populations. Cette introgression touche autant les populations d'abeilles élevées en ruches à cadres que celles maintenues en ruches-troncs. Ces populations ne se démarquent pas génétiquement l'une de l'autre.(III) La dernière partie de ce travail concerne la conservation du patrimoine apicole par l'établissement public du Parc national des Cévennes. Elle détaille les moyens et actions passés, présents, ainsi que les difficultés et les perspectives de conservation pour la ruche-tronc et l'abeille noire en contexte d'aire protégée. Cette partie met en exergue l'impérieuse nécessité d'une concertation multi-acteurs, axée sur une intégration de plusieurs types de savoirs — local, scientifique, d'expert — qui tienne compte des changements sociaux, économiques et écologiques auxquels la région des Cévennes est soumise. / For several centuries, the Cévennes region in Southern France has been renowned as a “land of honey”. Beekeeping in Cévennes is characterized by lo brusc, a traditional hive that is made of a hollowed chestnuts log which is covered with a schistous stone slab called “lauze”. Log hive apiaries are a very old and rustic form of beekeeping, which was a major driver of human occupation history and landscape dynamics throughout the Cévennes. From their origins, log hives were home most exclusively to black bees (Apis mellifera mellifera) that were settled in the region far before the rise of humankind. Nowadays, beekeeping in Cévennes is mainly carried out in frame hives. Current beekeeping practices — purchase of bees, transhumance, queen selection… — have led to a drastic decrease in populations of local bee subspecies, and to their genetic homogenization. In order to better understand and preserve this remarkable natural and cultural beekeeping heritage, the Cévennes National Park implemented a multidisciplinary study, through the funding of a CIFRE (Industrial contract for training through research) doctoral research.1- The first part of the study is dedicated to the hive. Archive documents strongly support the assertion that the very first log hives that were established in Cévennes date back to the end of the Middle Age. Afterwards they expanded and were maintained until the middle of the 20th century. The shift from log hive to frame hive occurred progressively throughout the past century. Testimonies by old Cévennes inhabitants helped assessing local practices, knowledge and know-how related to these traditional apiaries. Furthermore, spatial analyses were undertaken to characterize the micro-environment surrounding apiaries. These analyses corroborate local discourses about where an apiary should ideally be set up.2- The black bee is the epicenter of the second part of the study. From the common bee to the “black and aggressive” bee, views by the beekeeping community concerning the local bee in Cévennes have evolved over the past century. Genetic analyses using geometrical morphometry and mitochondrial DNA were successively implemented to establish a state of the art of local bee populations. Morphometric data tell us that nearly 2/3rd of the bee populations of Causses and Cévennes are composed of black bees. However, mitochondrial DNA data alert us on the high level of introgression within these populations. Such introgression equally affects bees kept in frame hives and those kept in log hives.3- The third part of the study addresses the sensitive issue of a conservation strategy of local beekeeping patrimony that is carried out by the public development agency of the Cévennes National Park. Past conservationist resources and actions are described and so are the perspectives and obstacles to a valuable conservation strategy of black bees and log hives in a context of protected area. In conclusion, the study advocates for an indispensable multi-stakeholder conciliation and a necessary integration of several types of knowledge — local ecological knowledge, knowledge from learned experts, scientific knowledge — that takes into consideration the social, economical and ecological changes affecting the overall Cévennes region.

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