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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 24 for “"Palearctic"”.
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Molecular Phylogenetic Analysis of Argynnis Fabricius (1807) including North American Speyeria Scudder (1872)
… studies of this group and the closely related Palearctic genus Argynnis , suggest that Speyeria is monophyletic but derived from within Argynnis . Sampling in these studies has either involved few basal Speyeria species, or too few Argynnis species (Simonsen 2006, Simonsen et al. 2006). Thus, …
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Citizen science reveals complex changes in barn swallow phenology in South Africa over three decades
Palearctic migrants, including barn swallows Hirundo rustica, responded to climate change in Europe from the mid to late 1900s with phenological changes, mostly showing earlier arrival and start of breeding. During this period, barn swallows in the Palearctic exhibited variable patterns of change …
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Impacts des changements climatiques passés et présents sur la génétique et la démographie du Cincle plongeur (Cinclus cinclus)
… the White-throated Dipper (Cinclus cinclus), a Palearctic, temperate, passerine bird that is exclusively associated with flowing water, reacted to the climate changes that occurred during the Pleistocene, and how climate change currently affects this species : - For this purpose, we conducted a …
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Cold winters vs long journeys : adaptations of primary moult and body mass to migration and wintering in the Grey Plover Pluvialis Squatarola
… wintering sites are reached. Across the Palearctic-African region Grey Plovers experience an enormous variety of ecological and climatic conditions, which determine the development of different moult patterns, according to local conditions and timing of migration.
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Revision of Pocadius Erichson (Coleoptera: Nitidulidae)
… monophyletic Pocadius. The phylogeny suggests a Palearctic origin of the genus with subsequent speciation into the Old World tropics and New World. Host specialization on gasteromycetes fungi by Pocadius species was shown not to be obligate but rather facultative. Some sympatric species were …
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Host range and multitrophic interactions between the parasitoid Cotesia vanessae (Hymenoptera: Braconidae) and Noctuidae (Lepidoptera) hosts in North America
… region, which was previously only known from the Palearctic and Afrotropic regions, I investigated its fundamental host range on North American Lepidoptera and found that it could parasitize a large number of species of Noctuidae. Its fitness varied among host species, and Plusiinae species …
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Systematics of Caenodelphax Fennah (Hemiptera: Fulgoroidea: Delphacidae) and description of the new genus Flavoclypeus
… definition, reducing it to only 10 western Palearctic species. This left the majority of Delphacodes species in need of reassignment to other genera. Hamilton (2002) hypothesized that 10 New World Delphacodes species belong to Caenodelphax Fennah, 1965. This project undertook an …
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COMPARATIVE BIOGEOGRAPHY OF NORTH AMERICAN PIKA PARASITES: UNRAVELING A HISTORY DRIVEN BY CLIMATE CHANGE
… cycle, as evidenced by multiple Nearctic and Palearctic lineage pairs that did not diverge simultaneously. This evidence indicates a pre-Pleistocene (>2.5Mya) history of multiple, independent colonizations of pikas and their parasites across Beringia primarily in an eastward direction. …
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Biogeography and phylogenetics of grassland auchenorrhyncha
… feeding in Deltocephalini was inferred to be Palearctic in origin, and Old World origins were inferred for each target lineage. Hecalini and Paralimnini were inferred to be Palearctic in origin, while Deltocephalini + Tetartostylini was more widespread and Caliscelinae was inferred to be …
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BERINGIAN BIOGEOGRAPHY: PATTERNS OF INTERCONTINENTAL DISPERSAL AND THE STRUCTURING OF A HOLARCTIC TAPEWORM GENUS
… facilitated the exchange of taxa between the Palearctic and Nearctic. While many studies have worked toward elucidating the role of Beringia in assembling northern faunas, relatively little work has focused on parasites. Here I examine the number and direction of transberingian colonization …
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Nesting Biology of Osmia cornifrons: Implications for Population Management
… cornifrons (Hymenoptera: Megachilidae) is a palearctic mason bee managed for the pollination of early season fruit crops such as apple and blueberry. Since its adoption as a managed pollinator in Japan during the 1940s, a large body of literature has amassed with the goal of enhancing O. …
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Phylogenetic Relationships of Tick Species in the <em>Ixodes ricinus</em> Complex, Derived from Mitochondrial Coi and 16S Genes
… species within the same geographic region (e.g. Palearctic/Oriental, Nearctic, Neotropical) are not sister taxa with each other. This might indicate that the ability to transmit the Lyme disease agent diverged on the different continents independently. </p>
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An Evolutionary and Ecological Investigation into the Enigmatic Stalked Puffball Genus Tulostoma
… genus. The phylogeographic analysis indicates a Palearctic origin for the genus. The phylogeography also suggests both vicariance and long-distance dispersal events contributing to the diversification of the species over the evolutionary history of the genus. The evolution of spore morphology is …
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Chromosomal inversions as a mechanism for sympatric differentiation in common quails
… and interbreeding in parts of the western Palearctic. This thesis assess how this rearrangement shapes population processes and contributes to divergence in sympatry. In Chapter 1, quails wintering in southern Iberia are analysed to determine the genetic composition of the wintering …
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Determinants of variation in productivity, adult survival and recruitment in a declining migrant bird : the Whinchat (Saxicola rubetra)
Populations of many species of Afro-Palearctic migrant birds, including the Whinchat (Saxicola rubetra), have shown severe declines over the last few decades. Habitat change on the breeding grounds, especially agricultural intensification, is thought to be the main driver of the decline in …
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Modelling Avian Distributions of the Navarrese Region in Northern Spain with a Geographic Information System
… corresponded to species which find part of their Palearctic distribution boundary within the study area. These findings seem to suggest that although climate controls directly where the boundaries of a biogeographic distribution are, habitat is more likely to determine occurrence/absence where …
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Aspects of the ecology of migrant shorebirds (Aves: Charadrii) at the Berg River estuary, South Africa
… were to assess the importance of the estuary for Palearctic-breeding migratory waders and to identify the factors affecting their distribution, abundance and behavioural patterns. The findings were related to the dispersion patterns of waders on the east Atlantic seaboard, and their significance …
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The identity, origin and impact of a 'new' buzzard species breeding in South Africa
… and Steppe Buzzard B. b. vulpinus, an abundant Palearctic migrant. Since the late 1970s and early 1980s, a number of buzzards appearing unlike B. trizonatus have been found breeding in the south-west Cape, particularly on the Cape Peninsula and in and around the Elgin Valley, ca.60km east of …
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