2024-03-29T14:56:06Z
https://www.duo.uio.no/oai/request
oai:www.duo.uio.no:10852/11762
2014-12-26T05:05:42Z
com_10852_22
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Evolutionary studies of uncultivated Radiolaria and their symbionts using Single Cell Whole Genome Amplification
Kamran Shalchian-Tabrizi, Jon Bråte, Kjell R. Bjørklund, Dag Klaveness
Understanding the evolution of eukaryotes and resolving the Tree of Life is one of the major goals of biology. Protists (unicellular eukaryotes) play a crucial role in this quest being the earliest diverging eukaryotes and as ancestors to all multicellular species. They display the largest diversity of all cellular forms, having photosynthetic-, heterotrophic-, saprotrophic-, parasitic- and symbiotic representatives in almost all of the world's ecosystems. The molecular study of protists, however, is currently burdened by the fact that many protists cannot be cultivated in the laboratory the traditional approach to grow the hundreds of cells needed for molecular studies. Methods needs to be developed to overcome this problem. Radiolaria belong to one such group of unculturable protists, and in this thesis they are used as a test system for developing a method that allows molecular study of protists based on single cell whole genome amplification (SCWGA).
Briefly the method consists of isolation of single cells from natural samples followed by an amplification step that in theory can amplify the entire genome from a single cell using the phi29 polymerase and random primers. The amplified genome is then subjected to 18S and 28S rDNA PCR and to shotgun sequencing using the 454 GS FLX Titanium pyrosequencing platform.
Retained genomic information is used in combined 18S and 28S rDNA phylogenies covering the major groups of Radiolaria in order to resolve their evolutionary relationship. In addition the 18S rDNA gene is obtained from several symbiotic cells from several different radiolarian species and used to infer the identity and diversity of the symbionts. Finally several mitochondrial markers are identified from the high throughput sequences.
2013-03-12
2010
2011-01-04
2011-03-09
10000-01-0
Master thesis
Krabberød, Anders Kristian. Evolutionary studies of uncultivated Radiolaria and their symbionts using Single Cell Whole Genome Amplification. Masteroppgave, University of Oslo, 2010
http://hdl.handle.net/10852/11762
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Krabberød, Anders Kristian&rft.title=Evolutionary studies of uncultivated Radiolaria and their symbionts using Single Cell Whole Genome Amplification&rft.inst=University of Oslo&rft.date=2010&rft.degree=Masteroppgave
URN:NBN:no-26785
110436
111913551
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11762/1/Anders_K_masterxA4.pdf
eng
Dette dokumentet er ikke elektronisk tilgjengelig etter ønske fra forfatter. Tilgangskode/Access code A
forever
closedaccess
oai:www.duo.uio.no:10852/11757
2017-12-07T12:58:29Z
com_10852_22
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Germline mutation rate of the microsatellite HrU10 in tree swallows, Tachycineta bicolor, in an area with high PAH pollution
Jan T. Lifjeld og Oddmund Kleven
mikrosatelitter tresvale mutasjonsrate Tachycineta bicolor PHA polysykliske aromatiske hydrokarboner
Abstract
Previous studies have revealed increased levels of germline mutations in minisatellite DNA in populations of herring gulls and mice sampled in Hamilton Harbour, Ontario Canada, an industrial area with high emissions of genotoxic contaminants like polycyclic aromatic hydrocarbons (PAH). In this study we investigated the occurrence of germline mutations of the highly mutable pentanucleotide microsatellite HrU10 in a population of free-living, migratory tree swallows breeding in the same area. We found a mutation rate of 5.3% (17/320 meiotic events) which was not statistically higher than that of a control population breeding in a rural and presumably unpolluted habitat in Eastern Ontario (3.4%; 14/412 meiotic events). In accordance with previous studies of microsatellite mutations, mutations were typical of slippage mutations with loss or gain of one (two) core repeat units, and the likelihood of mutation increased with the size of the microsatellite allele. We can not conclude that there is an effect of PAH on the HrU10 mutation rate, for that we would require a considerably larger data set to obtain statistical significance.
2013-03-12
2013-03-12
2009
2010-05-18
2010-07-08
Master thesis
Bentz, Kristofer H. Germline mutation rate of the microsatellite HrU10 in tree swallows, Tachycineta bicolor, in an area with high PAH pollution. Masteroppgave, University of Oslo, 2009
http://hdl.handle.net/10852/11757
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Bentz, Kristofer H&rft.title=Germline mutation rate of the microsatellite HrU10 in tree swallows, Tachycineta bicolor, in an area with high PAH pollution&rft.inst=University of Oslo&rft.date=2009&rft.degree=Masteroppgave
URN:NBN:no-24852
102751
101523114
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11757/2/Mutation_rate_of_HrU10_in_tree_swallows_v.Final.pdf
eng
oai:www.duo.uio.no:10852/11792
2014-12-26T05:05:42Z
com_10852_22
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Song response to male intruders and prospecting females in the pied flycatcher, Ficedula hypoleuca
Helene Lampe
biodiversitet fuglesang fluesnapper dobbelt funksjonsteori intersexual intrasexual
Singing in the pied flycatcher, Ficedula hypoleuca, was examined in both intra- and intersexual contexts. Song responses to male intruders and prospecting females were investigated by introducing caged conspecific birds into the subjects’ territory and recording song immediately prior and after treatment. Syllable repertoire, two measures of strophe diversity, strophe length and syllable switching were analysed using sonograms of the song. Pied flycatchers reduced their repertoire size and tended to increase their syllable switching and shorten their strophe length in response to intruding males. They did not significantly alter their song after encountering a female. Older males switched syllables at a higher rate after a female encounter than did juvenile males. Plumage traits were not correlated with song responses to males or to females. Pied flycatchers did not respond differentially to male intruders and prospecting females when responses to the two sexes were compared. The effect of nestbox provision and the migratory behaviour of these birds is discussed in relation to these findings. It is concluded that no strong indication of the dual function hypothesis hypothesis of birdsong was found in this study, though this may be a function of the sample size and further investigation may be warranted.
2013-03-12
2013-03-12
2009
2009-12-22
2010-01-05
Master thesis
Lambrou, Jayne Patricia. Song response to male intruders and prospecting females in the pied flycatcher, Ficedula hypoleuca. Masteroppgave, University of Oslo, 2009
http://hdl.handle.net/10852/11792
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Lambrou, Jayne Patricia&rft.title=Song response to male intruders and prospecting females in the pied flycatcher, Ficedula hypoleuca&rft.inst=University of Oslo&rft.date=2009&rft.degree=Masteroppgave
URN:NBN:no-23816
98058
100030351
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11792/1/JaynexLambrouxMastersxThesisxfinalxdraft.pdf
eng
oai:www.duo.uio.no:10852/11780
2014-12-26T05:05:42Z
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Climatic Change as an Engine for Speciation in Orthoptera Species: : Flightless Species on African Mountains as a Model System
Nils Christian Stenseth, Glenn-Peter Sætre, Øystein Flagstad
økologi evolusjon utvikling artsdannelse Afrika radiasjon gresshopper
Climatic fluctuations characterized the climate in East Africa during the Plio-Pleistocene. These variable conditions established opportunities for ecological fragmentation with subsequent genetic isolation of species dependent on both savannah and forest habitats. This study addresses the hypothesis that historical climatic fluctuations in the region have had a major evolutionary impact on the fauna in East Africa. To do this, mitochondrial DNA sequences from a group of bush crickets consisting of both forest and savannah inhabiting taxa were analyzed in relation to Plio-Pleistocene range fragmentations indicated by palaeoclimatic studies. Parts of the COI and 12S mitochondrial genes were sequenced to infer phylogeographic patterns. Coalescent modeling and mismatch distributions were used to distinguish between alternative biogeographic scenarios. The same methods, together with a traditional molecular clock approach, were also used to date the divergence times between species. The results indicate that two radiations, one between 6 and 3.5 million years ago and the other about 0.8 million years ago, gave rise to most of the species analyzed. The earliest radiation overlaps in time with the global spread of C4 grasslands and speciation through adaptation to this new type of plants may therefore explain the contemporary sudden burst of savannah inhabiting lineages. Climate seems to have been the driving force behind the more recent of the two radiations. An intensified drying and cooling of the climate right after the last warm and wet maximum in the region about 1 million years ago resulted in the retraction of forest to higher altitudes. Forest dependent species were consequentially trapped in forest refuges and simultaneous vicariant speciation events in these lineages followed. Accordingly, this study shows that the East African continental archipelago is a suitable model system for phylogenetic research and for illuminating how climatic fluctuations may influence speciation and other evolutionary processes. Further, my results suggest that savannah inhabiting species have experienced intense selective constraints on the mtDNA COI gene compared to forest dependent species. One possible explanation could be severe competition on the savannah for the right microclimate and food resources. Finally, paraphyly at both the genus and the species level was detected and some taxonomic revisions are suggested.
2013-03-12
2013-03-12
2007
2007-07-02
2007-09-18
Master thesis
Voje, Kjetil Lysne. Climatic Change as an Engine for Speciation in Orthoptera Species:. Masteroppgave, University of Oslo, 2007
http://hdl.handle.net/10852/11780
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Voje, Kjetil Lysne&rft.title=Climatic Change as an Engine for Speciation in Orthoptera Species:&rft.inst=University of Oslo&rft.date=2007&rft.degree=Masteroppgave
URN:NBN:no-15868
63230
071302166
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11780/1/thesisx-xKjetilxLysnexVoje.pdf
eng
oai:www.duo.uio.no:10852/11767
2017-12-07T12:58:30Z
com_10852_22
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Local distribution patterns of lichen epiphytes in a western Norwegian deciduous forest : relationship to available substrate
Rune Halvorsen, Einar Timdal
Environmental variables and epiphytic lichen flora of 279 deciduous rich bark trees of a boreonemoral rainforest in the oceanic region of Western Norway were studied. The lichen flora from base to breast height of the tree trunks was investigated for epiphytic macrolichens with cyanobacterial photobiont, 41 species were studied. Descriptive spatial patterns were summarised for each species based upon presence/absence data in two ways: by (1) point pattern analysis and (2) semivariance analysis, e.g. using the geoR package of the R software. Patterns of distribution of trees and their properties were summarised in the same ways (point pattern analysis applicable to geo-referenced tree occurrences only; not to their characteristics). Modelling of species presence (binary response variable) as function of the entire set of predictors was performed primarily using R software. The study revealed a main gradient from trees with great dimensions at low elevation in the north to trees with small dimensions at higher elevation in the south. Fourteen of the investigated lichen species were strongly affiliated with the north end of the gradient, nine species with the south end and only one was spread out evenly. Tree dimension and elevation were found to be the two most important environmental factors. Of the lichen species investigated 16 were oceanic, 24 indicators of long old forest continuity with high and stable humidity, 26 indicators of old deciduous forest continuity and 8 red-listed species. A total of 2/3 of trees investigated was pollarded and these trees had greater dimensions of the stem and higher species richness than the unpollarded 1/3. The old pollarding practice has almost ceased and the remaining pollards in the woodland are relicts (‘living deads’) with a limited lifespan, making the hot spot habitat in need of conservation and recruitment of new host trees.
2013-03-12
2013-03-12
2011
2012-02-13
2012-04-29
Master thesis
Myhre, Trude. Local distribution patterns of lichen epiphytes in a western Norwegian deciduous forest . Masteroppgave, University of Oslo, 2011
http://hdl.handle.net/10852/11767
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Myhre, Trude&rft.title=Local distribution patterns of lichen epiphytes in a western Norwegian deciduous forest &rft.inst=University of Oslo&rft.date=2011&rft.degree=Masteroppgave
URN:NBN:no-30458
151235
121344118
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11767/2/Myhre_Master.pdf
nob
oai:www.duo.uio.no:10852/11756
2014-12-26T05:03:55Z
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com_10852_1
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Migration patterns and taxonomy of Dryas octopetala L. in the North Atlantic region
Anne Krag Brysting, Marte Holten Jørgensen, Inger Nordal
Dryas babingtoniana reinrose biogeografi fylogeografi mikrosatellitter
The climatic fluctuations of the Quaternary have greatly influenced the distribution, composition and genetic structure of plant populations. Dryas octopetala sensu lato is an arctic-alpine plant belonging to a circumpolar genus where the species delimitation is disputed. In the present study, the genetic structure of D. octopetala plants (N = 292) from selected populations (N = 26) in the North Atlantic region was analysed using nine microsatellite markers to test for and discuss an independent western immigration route of North Western Norwegian populations and the taxonomic justification of D. babingtoniana. Population structure analyses revealed two main groups in D. octopetala in the North Atlantic region; a northern group and a southern group. These findings were further supported by principal coordinate and AMOVA analyses. The division into two groups probably reflect glacial survival in two different areas in the North Atlantic region. The analyses were ambiguous with regard to the question of an independent western immigration route for the North Western Norwegian populations of D. octopetala, and no evidence was found for the maintenance of more than one Dryas taxon (D. octopetala) in Scotland and North Western Norway. It is accordingly no justification for a babingtoniana-taxon at any taxonomic level.
2013-03-12
2010
2010-05-10
2010-07-08
10000-01-0
Master thesis
Pettersen, Christian. Migration patterns and taxonomy of Dryas octopetala L. in the North Atlantic region. Masteroppgave, University of Oslo, 2010
http://hdl.handle.net/10852/11756
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Pettersen, Christian&rft.title=Migration patterns and taxonomy of Dryas octopetala L. in the North Atlantic region&rft.inst=University of Oslo&rft.date=2010&rft.degree=Masteroppgave
URN:NBN:no-24851
102434
100517862
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11756/1/Masteroppgave_PettersenCE.pdf
eng
Dette dokumentet er ikke elektronisk tilgjengelig etter ønske fra forfatter. Tilgangskode/Access code A
forever
closedaccess
oai:www.duo.uio.no:10852/11761
2014-12-26T05:03:55Z
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Studies in the genera Anthericum and Chlorophytum with emphasis on Ethiopian taxa
Inger Nordal, Anne Brysting, Charlotte Bjorå, Tesfaye Awas
Abstract
85 specimens from the genera Anthericum L. and Chlorophytum Ker Gawl. were analysed, and a phylogeny based on the nuclear ITS1 and chloroplast rps16 and trnL-F sequences was produced. The results are used to discuss the generic delimitation of Anthericum and Chlorophytum which have been proven paraphyletic by Bjorå (2008). The results of this study support her findings. This analysis includes 24 specimens from Ethiopia, which previously have never been subjected to molecular analysis. The placements of these specimens in a phylogenetic setting are discussed, and the proposed transfer of Chlorophytum tetraphyllum to Anthericum is contradicted.
During field work specimen Elden 9 was first identified as Chlorophytum comosum, but preliminary molecular analyses showed relationship to C. gallabatense. This initiated further investigation of this specimen. Morphology analyses were preformed using Scanning electron microscopy (SEM) of seeds and character measurements of herbarium samples including the C. comosum complex and C. gallabatense to see if taxonomic recognition of the specimen Elden 9 is justified. The analyses showed that Elden 9 has at least three independent morphological characters that separate it from C. gallabatense and it will be referred to as Chlorophytum mamallium Elden & Nordal.
A SEM analysis of seeds from the genus Anthericum was undertaken, which contradicts the proposal by Kativu & Nordal (1993) that turgid seeds can be used as a character for generic delimitation of the genera Anthericum and Chlorophytum.
2013-03-12
2010
2010-12-01
2011-11-25
10000-01-0
Master thesis
Elden, Marte. Studies in the genera Anthericum and Chlorophytum with emphasis on Ethiopian taxa. Masteroppgave, University of Oslo, 2010
http://hdl.handle.net/10852/11761
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Elden, Marte&rft.title=Studies in the genera Anthericum and Chlorophytum with emphasis on Ethiopian taxa&rft.inst=University of Oslo&rft.date=2010&rft.degree=Masteroppgave
URN:NBN:no-26989
109249
112118976
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11761/1/MasterxthesisxM.Elden.pdf
eng
Dette dokumentet er ikke elektronisk tilgjengelig etter ønske fra forfatter. Tilgangskode/Access code A
forever
closedaccess
oai:www.duo.uio.no:10852/11772
2017-12-15T08:46:06Z
com_10852_22
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Fluctuating asymmetry in skulls of Svalbard and East Greenland polar bears (Ursus maritimus) in relation to time, geography and organohalogen pollution
Øystein Wiig, Christian Sonne
zoologi arktisk miljø isbjørn Ursus maritimus flukuerende asymmetri Svalbard Grønland hodeskalle kranium
Fluctuating asymmetry (FA) as a measure of environmental stress was studied in polar bear (Ursus maritimus) skulls from East Greenland (n = 300, collected during the period 1892-2004) and Svalbard (n = 391, collected during the period 1950-2004). Nine bilateral metric traits in skull and lower jaw were measured twice. The measured levels of FA for each trait were compared between sex/age groups (subadult, adult females, adult males), time periods (¡Ü1960 and >1960), and localities (East Greenland and Svalbard). The time period before 1960 was chosen to represent a period prior to the appearance of organohalogens (PCBs, HCB, HCHs, DDTs, dieldrin, CHLs, PBDEs, mirex) in the Arctic, while the time period after 1960 represents the period when the polar bears have been subjected to such organohalogens. One of the traits had a significantly higher degree of FA (for all sex/age groups) during the first period, while in two other traits, the subadults had a significantly higher FA during the second period. The Svalbard polar bears had a significantly higher FA in one trait than did the bears from East Greenland. This latter trend was reflected in the investigation of a pooling of four of the traits. Levels of fluctuating asymmetry of each trait were furthermore assessed over time on bears born during the period 1950-2004. The polar bears were divided into sex/age groups, but not according to locality. All significant results from these analyses had a negative slope, with FA decreasing over the period of time. Correlation analyses of FA for each trait versus the levels of contaminants in adipose tissue samples was performed for a subsample of the East Greenland polar bears, collected recently (1999-2002). The majority of the significant results of these correlation analyses showed a negative trend in the data, with higher levels of FA corresponding to lower levels of contaminants.
Overall, the present study showed no substantial evidence of a relation between levels of FA and organochlorines. Instead, the indications were of subpopulations with generally declining levels of FA over time, suggesting the existence of positive population level effects powerful enough to overrule the negative influence of stress caused by factors such as global warming, pollution, and overharvesting. Or, alternatively, a) that the individuals with the highest levels of stress and thus ditto values of FA are aborted or die as neonates, and thus are not included in the collections of polar bears examined in the present study, b) that FA of metric skulls traits is not a suitable predictor of stress in polar bears, c) that the organohalogen toxic loads are not at high enough levels to elicit a measurable positive response in the FA of the examined polar bears.
2013-03-12
2006
2006-08-31
2012-12-07
Master thesis
Bechshøft, Thea Østergaard. Fluctuating asymmetry in skulls of Svalbard and East Greenland polar bears (Ursus maritimus) in relation to time, geography and organohalogen pollution. Masteroppgave, University of Oslo, 2006
http://hdl.handle.net/10852/11772
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Bechshøft, Thea Østergaard&rft.title=Fluctuating asymmetry in skulls of Svalbard and East Greenland polar bears (Ursus maritimus) in relation to time, geography and organohalogen pollution&rft.inst=University of Oslo&rft.date=2006&rft.degree=Masteroppgave
URN:NBN:no-14002
43986
061371246
eng
oai:www.duo.uio.no:10852/11765
2017-12-07T12:58:30Z
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Mitochondrial Ewe - application of ancient DNA typing to the study of domestic sheep (Ovis aries) in mediaeval Norway
Erika Hagelberg, Vidar Kaspersen, Ketil Hylland
Around 11000 years ago the first domesticated mammals emerged in the Fertile Crescent.
Over time, these animals spread to fertile regions both to the east and west of their domestic
centre of origin. By 6000 BP, animal husbandry had reached Northern Europe, and it had
become established in Norway by circa 4100 BP. Domestic sheep (Ovis aries) was probably
among the first domestic species to be introduced to Norway and by the Middle Ages (476-
1453 AD) animal husbandry and sheep herding was well established here. Not much is known
about the composition of domestic sheep in mediaeval Norway, but it has been suggested that
new breeds were introduced from other countries as this was a time of increasing trade.
Four different mitochondrial DNA (mtDNA) haplogroups, known as A, B, C and D,
have been observed in domestic sheep, of which mtDNA haplogroup A and B are found in
Europe. In this study I analysed genetic data obtained from sheep bones excavated from
archaeological sites (Oslo, Bergen and Trondheim) in Norway dated to the Middle Ages (476-
1453 AD). I also included a bone sample dated to the Viking Age (800-1066 AD) to see if any
genetic variation could be obtained from an older sample. I implemented methods for
extracting ancient mtDNA from bones, and aimed to produce reliable extracts that could be
authenticated as mediaeval sheep DNA. Authentic mtDNA sequences of mediaeval domestic
sheep could provide information that would help answer questions regarding the trading
history and composition of breeds at different geographical regions in mediaeval Norway.
Sheep extracts were amplified with sheep specific primers and cytochrome b primers
simultaneously. Negative and positive controls, as well as samples of different species were
included in the amplifications. PCR amplifications visualised on electrophoresis agarose gels
could exclude human and cross-contamination of sheep by the nature of the controls. This
suggested that the genetic data were authentic. Of 70 domestic sheep samples, 16 were
successfully sequenced, including one from the Viking Age. Two mtDNA haplogroups were
observed: A and B. One specimen from Trondheim was allocated to haplogroup A, whereas
the remaining samples were haplogroup B. The 16 sequences used in the phylogenetic
analyses were short (88 bp), and thus not informative enough to settle questions regarding the
trade and composition of breeds in mediaeval Norway. However, it could be concluded that
the sheep sequences were authentic, and that two mtDNA sheep lineages were present in
Norway in the Middle Ages.
2013-03-12
2013-03-12
2010
2011-04-14
2011-11-25
Master thesis
Bollvåg, Anette Øwre. Mitochondrial Ewe - application of ancient DNA typing to the study of domestic sheep (Ovis aries) in mediaeval Norway. Masteroppgave, University of Oslo, 2010
http://hdl.handle.net/10852/11765
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Bollvåg, Anette Øwre&rft.title=Mitochondrial Ewe - application of ancient DNA typing to the study of domestic sheep (Ovis aries) in mediaeval Norway&rft.inst=University of Oslo&rft.date=2010&rft.degree=Masteroppgave
URN:NBN:no-27603
115755
114874735
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11765/2/Mit_Ewe_PDF.pdf
nob
oai:www.duo.uio.no:10852/11774
2013-03-12T08:45:14Z
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Phylogenetic inference of Telonemia and eukaryotic supergroups using multi-gene sequence data
Kjetill Jakobsen & Kamran Shalchian-Tabrizi
fylogeni proteiner multigener eukaryoter Telonemiachromalveolutter
Over the past 2 decades major advancements in phylogenetics have been made and this in turn
has influenced our understanding of eukaryotic evolution. The use of morphological data
combined with sequence data has been the basis for the recent division of eukaryotes into five
supergroups . This hypothesis is yet to be proven, as a general lack of both taxon and gene
sequences has only led to the resolution of some of the groups. The chromalveolates are
possibly the most contested of these groups, and it remains to be proven if they belong to one
major lineage or several distinct groups. Chromalveolate resolution has been suggested to be
dependent on the sampling of residual lineages. One such phylum, Telonemia, has been
recently inferred with a two-gene phylogeny, indicating an affinity to two groups belonging to
the chromalveolates, the cryptomonads and haptophytes. This placement however was weakly
supported and a more conclusive phylogeny is vital to the further understanding of
chromalveolates and other eukaryotic supergroup relationships. For this purpose an
orthologous multigene phylogeny of 9 nuclear protein coding genes and the small subunit
(SSU) rRNA gene from Telonema and a broad sampling of eukaryotic taxa was used for
phylogenetic inferences. Five of these Telonema protein-coding sequences were amplified for
the purpose this study; the remainder were generated from previous studies. The resulting 10
gene global eukaryotic phylogeny is the largest dataset as yet to include broad sampled taxa
from all five of the hypothesized supergroups. The phylogentic analysis again placed
Telonema as a deep eukaryotic lineage, increased gene and taxon sampling inferred stronger
phylogenetic affinity to the cryptomonads, haptophytes and a third chromalveolate group of
katablepharids. The backbone of the global eukaryotic phylogeny however could not resolve
the monophyly of chromalveolates, alternatively placing the group into three separate clades.
Otherwise, the result demonstrated strong monophyly for thee other supergroups, the
unikonts, Rhizaria and for the first time Excavata. The fifth supergroup of plants only
demonstrated monophyly with two of its three lineages, here identified to be caused by
phylogenetic artifacts. A focus toward the addition of both genes and taxa should be
prioritised for our further understanding of the relationships between the eukaryotic
supergroups.
2013-03-12
2013-03-12
2007
2007-02-21
2007-03-16
Master thesis
Orr, Russell John Scott. Phylogenetic inference of Telonemia and eukaryotic supergroups using multi-gene sequence data. Masteroppgave, University of Oslo, 2007
http://hdl.handle.net/10852/11774
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Orr, Russell John Scott&rft.title=Phylogenetic inference of Telonemia and eukaryotic supergroups using multi-gene sequence data&rft.inst=University of Oslo&rft.date=2007&rft.degree=Masteroppgave
URN:NBN:no-14495
53209
070326363
eng
oai:www.duo.uio.no:10852/11786
2014-12-26T05:05:43Z
com_10852_22
com_10852_1
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Mulitlocus sequence analyses of the near threatened Semi-collared flycatcher (Ficedula semitorquata) and a comparison with three other Ficedula flycatcher species
Glenn-Peter Sætre
genetisk variasjon genetikk Balkanfluesnapper fluesnapper fylogeni
The Semi-collared flycatcher (Ficedula semitorquata) is a member of the black-and-white flycatcher species complex. It is poorly studied, rare, and is currently classified as “near threatened”, in the IUCN red lists of threatened species. The Semi-collared flycatcher has a patchy distribution in Europe and part of the Middle East. In this study, I analyzed sequence variation at nuclear loci of Semi-collared flycatchers, and compared the patterns found with those of three other black-and-white flycatcher species, the Pied (F. hypoleuca), Collared (F.albicollis) and Atlas flycatchers (F. speculigera). Genetic variation was found to be relatively high, compared to the other three flycatcher species and there were no signs of inbreeding. All four flycatcher species had less variation at Z-linked loci compared to autosomal loci. A comparison showed that all species combinations had fewer shared polymorphisms and more fixed substitutions at Z-linked than at autosomal loci. Selective sweeps on the Z-chromosome during the evolutionary history of these species is likely to have contributed to this pattern. A mismatch distribution showed signs of a recent population expansion in all four species, and a phylogenetic reconstruction confirmed a relatively deep split and that each species is monophyletic. This study supports the classification of the Semi-collared flycatcher as a separate species. Even though no signs of a small population size are found here, it is important to keep monitoring this bird, since it has gone through several declines across Europe during the last decades. Much of the decline is probably due to habitat destruction, so it is important to retain old forest in the habitat of the species.
2013-03-12
2013-03-12
2008
2008-06-13
2008-07-03
Master thesis
Hogner, Silje. Mulitlocus sequence analyses of the near threatened Semi-collared flycatcher (Ficedula semitorquata) and a comparison with three other Ficedula flycatcher species. Masteroppgave, University of Oslo, 2008
http://hdl.handle.net/10852/11786
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Hogner, Silje&rft.title=Mulitlocus sequence analyses of the near threatened Semi-collared flycatcher (Ficedula semitorquata) and a comparison with three other Ficedula flycatcher species&rft.inst=University of Oslo&rft.date=2008&rft.degree=Masteroppgave
URN:NBN:no-19138
79312
081008848
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11786/1/MicrosoftxWordx-xMultilocusxsequencexanalysesxofxthexnearxxxxxxthreatenedxSemi.pdf
eng
oai:www.duo.uio.no:10852/11794
2017-12-07T12:58:30Z
com_10852_22
com_10852_1
col_10852_28
On the origin of an avian species by means of natural hybridization
Glenn-Peter Sætre, Stein Are Sæther, Thomas Borge
evolusjon hybrid artsdannelse fugl spurv hybridisering
Hybrid speciation has until recently been largely neglected by zoologists. This attitude is now changing. However, data is still scarce, and published examples include few taxa. In this thesis I present the first genetic evidence for hybrid speciation in birds, the long held example of the Italian Sparrow Passer italiae. This bird is intermediate in phenotype between its putative parental taxa, House Sparrow Passer domesticus and Spanish Sparrow Passer hispaniolensis, and its distribution is limited to the Italian peninsula, falling between the much larger distributions of its putative parentals. I analyzed variation in both nuclear (751 individuals genotyped for 14 microsatellite loci) and mitochondrial (21 individuals analyzed for 967 bp of the ND2 gene) markers. Individuals analyzed were sampled over the whole distribution of the Italian Sparrow, including the contact zones with both putative parental taxa as well as areas where these live in allopatry. FST and RhoST-estimates show low but consistent values, and indicate that the Italian Sparrow is intermediate in divergence between the House Sparrow and Spanish Sparrow. Further, Bayesian cluster analysis conducted in STRUCTURE reveals two genetic clusters, clearly corresponding to the House Sparrow and Spanish Sparrow, and assigns Italian Sparrows partially to both clusters. I found evidence of a cline in assignment probabilities in the area of phenotypically pure Italian Sparrows, i.e. assignment to the House Sparrow decreases towards the south, which I interpret as introgression from the House Sparrow. Phylogenetic analyses of the mitochondrial ND2 gene show that the Italian Sparrow is indistinguishable from House Sparrow at this marker whereas Spanish Sparrows form a distinct clade, well differentiated from the House/Italian Sparrow-clade. I argue that, taken together, these results reveal a mixed nuclear genome of recent origin, and hence that the Italian Sparrow is a recently formed homoploid hybrid species. I propose a novel scenario of its origin rooted in the agricultural revolution, and discuss its taxonomic status as well as its future.
2013-03-12
2009
2010-02-05
2010-02-18
10000-01-0
Master thesis
Hermansen, Jo Skeie. On the origin of an avian species by means of natural hybridization. Masteroppgave, University of Oslo, 2009
http://hdl.handle.net/10852/11794
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Hermansen, Jo Skeie&rft.title=On the origin of an avian species by means of natural hybridization&rft.inst=University of Oslo&rft.date=2009&rft.degree=Masteroppgave
URN:NBN:no-24229
99094
093553676
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11794/1/JoxSkeiexHermansenxx050110xxDUOx.pdf
eng
Dette dokumentet er ikke elektronisk tilgjengelig etter ønske fra forfatter. Tilgangskode/Access code A
forever
closedaccess
oai:www.duo.uio.no:10852/11773
2017-12-15T08:37:01Z
com_10852_22
com_10852_1
col_10852_28
Studies of generic and specific delimitation of the genera Drimiopsis and Ledebouria (Hyacinthaceae)
Brita Stedje and Anne Krag Brysting
botanikk Drimiopsis Lebebouria morfologi DNA-sekventering artsavgrensning slektsavgrensning
The monocot genera Ledebouria and Drimiopsis belong to the family Hyacinthaceae in the order Asparagales. The aim of this study was to investigate the generic delimitation between the two genera using DNA sequencing, and to investigate the specific delimitation within Ledebouria using both morphological and molecular characters.
For the molecular analysis the Drimiopsis and Ledebouria specimens were sequenced for three chloroplast regions; trnL intron, trnL-F intergenic spacer and trnS-G intergenic spacer. In the strict consensus tree of the combined analysis of the three regions, the two genera each form a monophyletic group (though without any bootstrap or jackknife support), supporting the recognition of two separate genera.
For the morphological investigation 22 Ledebouria specimens were investigated using univariate and multivariate analyses of altogether 19 qualitative and quantitative characters. The analyses of the morphological data provided not enough information for the proposal of a final specific delimitation within Ledebouria, but together with the molecular phylogeny they suggested that six tentative taxa may be identified within the genus Ledebouria; L. kirkii, two groups of broad leaved taxa (L. cordifolia and one unnamed taxon), and three groups within the L. revoluta complex. The characters leaf width, leaf length, perianth segment length, leaf threads, spotting pattern of the leaves and ovary shape seem to be the most important morphological characters for delimiting these taxa. However, more investigations (morphological and molecular) including more specimens from all geographical regions is needed to confirm this result.
Keywords; Drimiopsis, Ledebouria, morphology, DNA sequencing, generic and specific delimitation.
2013-03-12
2007
2007-01-10
2007-03-13
Master thesis
Tindamanyire, Neema. Studies of generic and specific delimitation of the genera Drimiopsis and Ledebouria (Hyacinthaceae). Masteroppgave, University of Oslo, 2007
http://hdl.handle.net/10852/11773
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Tindamanyire, Neema&rft.title=Studies of generic and specific delimitation of the genera Drimiopsis and Ledebouria (Hyacinthaceae)&rft.inst=University of Oslo&rft.date=2007&rft.degree=Masteroppgave
URN:NBN:no-14498
51528
070052050
eng
oai:www.duo.uio.no:10852/11766
2014-12-26T05:03:03Z
com_10852_22
com_10852_1
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Multilocus sequence analysis of the house sparrow (Passer domesticus), Spanish sparrow (P. hispaniolensis) and their putative hybrid descendant, the Italian sparrow (P. italiae)
Glenn-Peter Sætre
Homoploid hybrid speciation in animals is poorly understood compared to the classic bifurcating mode of species diversification, mainly because of the scarcity of well-documented cases. Here, I presents the results of a multilocus sequence analysis on the house sparrow (Passer domesticus), Spanish sparrow (P. hispaniolensis) and their proposed hybrid descendant, the Italian sparrow (P. italiae). The Italian sparrow is shown to be genetically intermediate between the house sparrow and Spanish sparrow, exhibiting genealogical discordance and a mosaic pattern of alleles derived from either of the putative parental species. Further, as the Z chromosome previously has been shown to have a predominant role in bifurcation speciation in birds, I analyzed variation and divergence at autosomal and Z-linked genes, as well as one mitochondrial gene in the three sparrow taxa. Average variation on the Z was significantly reduced compared to autosomal variation in the putative parental taxa. Additionally, interspecific divergence between the two latter taxa was elevated on the Z relative to the autosomes. This pattern of variation and divergence is consistent with a faster-Z effect
(increased rate of adaptive divergence on the Z) and/or reduced introgression of Z-linked genes e.g. due to increased selection against foreign alleles in hybrids and backcrosses (Haldane’s rule).
FST-outlier tests were consistent with the faster-Z hypothesis. Two out of five Z-linked loci were identified as candidates for positive, divergent selection. In addition, isolation with migration analysis
was also consistent with reduced introgression of Z-linked genes, since the estimated rate of gene flow after the initial split of the house sparrow and Spanish sparrow was higher for the autosomal than the Z data set. Interestingly, the two Z-linked candidate loci for positive selection (CHD1Z and PLAA) showed a clearer mosaic pattern in the putative hybrid species than any of the autosomal markers. The Italian sparrow was fixed for Spanish sparrow alleles at CHD1Z and possessed mostly house sparrow alleles at PLAA. I argue that the present results, together with results from another recent study on the same species complex, provide one of the strongest cases of hybrid
speciation in animals.
2013-03-12
2013-03-12
2011
2011-09-20
2011-11-25
10000-01-0
Master thesis
Elgvin, Tore Oldeide. Multilocus sequence analysis of the house sparrow (Passer domesticus), Spanish sparrow (P. hispaniolensis) and their putative hybrid descendant, the Italian sparrow (P. italiae). Masteroppgave, University of Oslo, 2011
http://hdl.handle.net/10852/11766
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Elgvin, Tore Oldeide&rft.title=Multilocus sequence analysis of the house sparrow (Passer domesticus), Spanish sparrow (P. hispaniolensis) and their putative hybrid descendant, the Italian sparrow (P. italiae)&rft.inst=University of Oslo&rft.date=2011&rft.degree=Masteroppgave
URN:NBN:no-29626
135855
114877394
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11766/1/Masteroppgave_Tore_Oldeide_Elgvin.pdf
eng
Dette dokumentet er ikke elektronisk tilgjengelig etter ønske fra forfatter. Tilgangskode/Access code A
forever
closedaccess
oai:www.duo.uio.no:10852/11771
2014-12-26T05:05:45Z
com_10852_22
com_10852_1
col_10852_28
"Escape of Introduced Ornamentals in Asteraceae" : with main focus on Tagetes patula L. in Western Ethiopia
Intern: Professor Inger Nordal, Ekstern: Stipendiat Tesfaye Awas
biodiversitet evolusjon invandrende planteart ornamental-forvandling ugress Tagetes patula Ethiopia
Introduced plant species may lead to negative consequences for the local community by outcompeting other species, and in extreme situations decrease biodiversity. It is well known that once an invasive species becomes firmly established, its control might be difficult and eradication may be more or less impossible.
Benshangul Gumuz National Regional State in Western Ethiopia inhabits several endemics, and is not very well studied, so far. Features of Tagetes patula and Zinnia elegans, two introduced ornamentals that has escaped cultivation in the area, will in this thesis be studied. The endemic species Bidens prestinaria will be used in some of the experiments for comparison. People in Western Ethiopia are dependent on their crops. An increasing growth of the already naturalized ornamentals might have negative consequences in this regard.
Successful invasion is associated by characteristics as (among others), a large seed production, a soil seed bank, a rapid growth rate, and a stimulated growth of side shoots after grazing/trampling. Tagetes patula possess all these characteristics. Zinnia elegans was not found escaped to the same degree as Tagetes patula, and was accordingly regarded not to be as potentially invasive as T. patula.
A species association analysis revealed that Tagetes patula was mainly found in the association characterised by tree species, and the association was also containing species demanding some shade and moisture. It was less frequently found in associations were the species composition represented open and more arid habitat types. Bidens prestinaria, however, preferred both associations.
To study if fire could be a way to control the species, diaspores of T. patula and Z. elegans were exposed to different fire simulation treatments. Surprisingly, the result suggested that diaspores of the two ornamental species, to a certain degree will withstand fire, unless the heat becomes excessive. The near endemic species Bidens prestinaria was apparently not affected by the heat treatments.
2013-03-12
2013-03-12
2006
2006-06-07
2006-06-30
Master thesis
Salvesen, Agnethe Birkeland. "Escape of Introduced Ornamentals in Asteraceae" . Masteroppgave, University of Oslo, 2006
http://hdl.handle.net/10852/11771
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Salvesen, Agnethe Birkeland&rft.title="Escape of Introduced Ornamentals in Asteraceae" &rft.inst=University of Oslo&rft.date=2006&rft.degree=Masteroppgave
URN:NBN:no-12443
41963
061070009
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11771/1/MASTER-ABS%5B1%5D.pdf
eng
oai:www.duo.uio.no:10852/11785
2014-12-26T05:05:45Z
com_10852_22
com_10852_1
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Beak morphology in oviraptorids, based on extant birds and turtles
Glenn-Peter Sætre & Jørn Harald Hurum
dinosaurer oviraptor skilpadder fugler papegøyer nebb skalle hodekam anatomi
Oviraptorids are one of several groups of dinosaurs which have evolved beaks. Of extant beaked animals, birds and turtles are the best known. In this study, an anatomical comparison between oviraptorids, extant birds and turtles was made to try to reconstruct the beak in oviraptorids. The results show a close similarity in mandibular beak shape of parrots and oviraptorids, whereas turtles deviate. In the upper jaw, the oviraptorids show more resemblance to the latter group. The same bones, namely the premaxilla but also the maxilla and the nasal, were covered by ramphotheca in almost all the groups of birds, as well as in oviraptorids and turtles. Comparative evidence suggests that oviraptorids may have had a beak suited for an omnivorous diet, and the diet primarily consists of small prey, but also eggs, nuts and hard seeds.
Keywords: oviraptorids, parrots, turtles, ramphotheca, skull anatomy, crest.
2013-03-12
2013-03-12
2008
2008-03-28
2008-07-03
Master thesis
Jansen, Stig Olav Krekvik. Beak morphology in oviraptorids, based on extant birds and turtles. Masteroppgave, University of Oslo, 2008
http://hdl.handle.net/10852/11785
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Jansen, Stig Olav Krekvik&rft.title=Beak morphology in oviraptorids, based on extant birds and turtles&rft.inst=University of Oslo&rft.date=2008&rft.degree=Masteroppgave
URN:NBN:no-18990
71351
081008910
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11785/1/Jansenx2008x-xBeakxmorphologyxinxoviraptoridsxxbasedxonxextantxbirdsxandxturtlesxxCompressedxpicturesx.pdf
eng
oai:www.duo.uio.no:10852/11781
2017-12-07T12:58:30Z
com_10852_22
com_10852_1
col_10852_28
The history of the Polynesians inferred from high resolution HLA data.
Prof. Erika Hagelberg
populasjonsgenetikk evolusjonsgenetikk økologi
Numerous scientific investigations have been undertaken to answer the question of Polynesian origins. Most archaeological and linguistic evidence and previous studies in population genetics suggested that Remote Oceania was settled from the west. The human colonization of the Pacific began with the settlement of Australia and Papua New Guinea (PNG) at least 40,000 years ago, and was followed by the settlement of Remote Oceania, starting about 3,500 years ago. Most scholars agree that present-day Polynesians originated in Southeast Asia, and first entered the region as Neolithic agriculturalists. But the questions of the character of colonization and the extent of the Melanesian contribution to the Polynesian gene pool, as well possible South American contacts, still prevail. Certain plants, such as the sweet potato and bottle gourd, indicate some contacts with South America. Moreover, the Norwegian explorer Thor Heyerdahl showed that a voyage from South America was physically possible, even though no direct evidence of Amerindian ancestry has been found. Interestingly, recent research on the HLA system showed a significant South American genetic component in Easter Island.
In order to address the issue of possible ancient contacts between Polynesia and South America, and to investigate the genetic affinities of the Eastern Polynesians, 52 human genomic DNA samples from three locations in Eastern Polynesia (Southern Marquesas, Mangareva and Western Samoa) were tested for HLA polymorphisms. The results indicate that the Eastern Polynesians are principally derived from Southeast Asia. Some recent European admixture was detected, most likely due to post-European contacts. Several polymorphisms point to a possible North Asian connection (DRB1*0405 and DRB1*1201) and other, rare elements (e.g. A*0212, B*3905 and DRB1*1402) are clear evidence of South American admixture. No significant Melanesian ancestry was found. Phylogenetic analysis showed that the Polynesians studied did not differ significantly from Southeast Asian populations of mixed origins (such as Malay, Filipino, East Timorese and Moluccans) but have very little in common with the present-day inhabitants of Papua New Guinea. The results, however, could be the effect of sampling variance or genetic drift in Polynesia. In general, the HLA polymorphisms observed in this study give further support to the ‘Express train’ model of the colonization of the Pacific.
2013-03-12
2013-03-12
2007
2007-09-10
2007-09-18
Master thesis
Krzewinska, Maja. The history of the Polynesians inferred from high resolution HLA data.. Masteroppgave, University of Oslo, 2007
http://hdl.handle.net/10852/11781
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Krzewinska, Maja&rft.title=The history of the Polynesians inferred from high resolution HLA data.&rft.inst=University of Oslo&rft.date=2007&rft.degree=Masteroppgave
URN:NBN:no-15859
65248
071301186
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11781/2/MasterMaja305007_EH4.pdf
eng
oai:www.duo.uio.no:10852/11770
2014-12-26T05:05:45Z
com_10852_22
com_10852_1
col_10852_28
Variation in testis size and sperm morphology in the bluethroat, Luscinia svecica svecica
Jan T. Lifjeld
zoologi blåstrupe spermiekonkurranse testikkelstørrelse farskap ekstraparfarskap
In this study I examined intra-specific variation in primary sex traits in male bluethroats (Luscinia svecica svecica), a passerine species with a high intensity of sperm competition, The single most important predictor of the size of testes and seminal glomera was male age (yearlings versus older). This finding suggests that older males have higher sperm production rates, which may allow for higher copulation rates and/or larger ejaculates than in younger males. Previous findings of older males having a higher extra-pair fertilization success, and similar paternity loss in own nest as younger males despite less intense mate guarding, contribute to a general pattern of age-dependent sperm competition investments in male bluethroats. None of the measured conditional variables (body mass, haemoglobin, haematocrit), nor the body size variables (wing length, tarsus length, scull length) correlated significantly with testis size. The bluethroat sperm were relatively long (216.4 µm, n=46, SD=3.1µm) as expected for a species with intense sperm competition. Between-male variation in average sperm length was considerably larger than the within-male variation in individual sperm length. However, the between-male coefficient of variation in mean sperm length was considerably lower than that reported recently for another passerine with low intensities of sperm competition. More species should be examined to test for a possible relationship between inter-male variation in sperm length and the intensity of sperm competition.
2013-03-12
2013-03-12
2005
2005-12-15
2006-03-10
Master thesis
Laskemoen, Terje. Variation in testis size and sperm morphology in the bluethroat, Luscinia svecica svecica. Masteroppgave, University of Oslo, 2005
http://hdl.handle.net/10852/11770
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Laskemoen, Terje&rft.title=Variation in testis size and sperm morphology in the bluethroat, Luscinia svecica svecica&rft.inst=University of Oslo&rft.date=2005&rft.degree=Masteroppgave
URN:NBN:no-11926
34264
060442468
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11770/1/Laskemoen_2005.pdf
eng
oai:www.duo.uio.no:10852/11777
2014-12-26T05:05:46Z
com_10852_22
com_10852_1
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Beak morphology in extant birds with implications on beak morphology in ornithomimids
Glenn-Peter Sætre og Jørn Harald Hurum
paleontologi morfologi nebb fugler dinosaurer
Ornithomimosaurs are only one out of several dinosaurian groups that at some point evolved beaks. The morphology of this beak and its relation to dietary habits have long been debated.Birds and turtles are the primary extant beaked organisms. Many studies have previously been conducted with the emphasis on beak shape and sensory organ topography in relation to feeding habit and behaviour. Few have, however, focused on both external and internal morphology and their correlations. This study focuses on comparative anatomy between extant birds and ornithomimid dinosaurs in an effort to reconstruct the beaks of these gracile dinosaurians. The results show a close relation in shape between the examined birds and the
ornithomimids, and point towards a beak suited for omnivory (feeding on animals small enough to swallow whole) or high-fibre herbivory.
2013-03-12
2013-03-12
2007
2007-06-11
2007-07-10
Master thesis
Knutsen, Espen Madsen. Beak morphology in extant birds with implications on beak morphology in ornithomimids. Masteroppgave, University of Oslo, 2007
http://hdl.handle.net/10852/11777
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Knutsen, Espen Madsen&rft.title=Beak morphology in extant birds with implications on beak morphology in ornithomimids&rft.inst=University of Oslo&rft.date=2007&rft.degree=Masteroppgave
URN:NBN:no-15166
62210
07097229x
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11777/1/Beakxmorphologyxinxextantxbirdsxwithximplicationsxonxbeakxmorphologyxinxornithomimosaurs_comp.pdf
eng
oai:www.duo.uio.no:10852/11790
2014-12-26T05:05:47Z
com_10852_22
com_10852_1
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The fungal community associated with roots of alpine and arctic Dryas octopetala along a latitudinal gradient
Håvard Kauserud (hovedveileder), Tor Carlsen, Trude Vrålstad, Klaus Høiland og Trond Schumacher
The ectomycorrhizal (ECM) dwarf shrub Dryas octopetala is one of the hardiest and most abundant of all woody plant groups in alpine and arctic environments. The main aim of this study was to characterise the fungal communities associated with D. octopetala roots along a latitudinal gradient from Southern Norway to the high Arctic (Svalbard). Twenty-six root systems were sampled at five main localities (13 sub-localities) and the internal transcribed spacer (ITS) amplified from DNA extracts from pooled root samples using fungal specific primers. Twenty-four cloned ITS fragments were obtained from each root system and the taxonomic affinity of the sequences were analyzed by DNA homology searches against UNITE and GenBank, as well as own reference sequences obtained from collected basidiocarps.
A total of 138 Operational Taxonomic Units (OTUs) were detected, 76 belonging to Basidiomycota, 59 to Ascomycota, two to Zygomycota, and one to Glomeromycota, demonstrating that an ecologically and phylogenetically diverse array of fungi is associated with the roots of D. octopetala. The most frequently detected taxonomic order was Agaricales, followed by Thelephorales, Cantharellales and Helotiales. The majority of the environmental sequences had taxonomic affinity to well-known ECM genera such as Hebeloma, Cortinarius, Tomentella, and Inocybe. Most of the environmental sequences with affinity to ascomycetes represented ECM, such as Cenoccoccum geophilum and Cadophora finladia, or endophytic fungi including dark septate endophyes (DSE) such as Phialocephala fortinii. These taxa were widespread and found in all but the southernmost main locality.
Non-asymptotic species accumulation curves and the occurrence of a high number of singletons indicate that only a small fraction of the fungal diversity was detected. The spatial heterogeneity in the fungal communities associated with D. octopetala was high, both within and between sub-localities and between main localities, but a slight geographic structuring of the composition of OTUs in the root systems was observed. There was no decrease in fungal diversity with increasing latitude, which contrasts observations made in a wide spectrum of other organism groups.
2013-03-12
2009
2009-09-10
2009-09-11
10000-01-0
Master thesis
Bjorbækmo, Marit Markussen. The fungal community associated with roots of alpine and arctic Dryas octopetala along a latitudinal gradient. Masteroppgave, University of Oslo, 2009
http://hdl.handle.net/10852/11790
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Bjorbækmo, Marit Markussen&rft.title=The fungal community associated with roots of alpine and arctic Dryas octopetala along a latitudinal gradient&rft.inst=University of Oslo&rft.date=2009&rft.degree=Masteroppgave
URN:NBN:no-23065
94671
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11790/1/Bjorbekken_final.pdf
eng
Dette dokumentet er ikke elektronisk tilgjengelig etter ønske fra forfatter. Tilgangskode/Access code A
forever
closedaccess
oai:www.duo.uio.no:10852/11778
2017-12-07T12:58:31Z
com_10852_22
com_10852_1
col_10852_28
A description and phylogenetic relationship of a polycotylid plesiosaur (Reptilia: Sauropterygia) from the Upper Cretaceous (Turonian) of Goulmima, Morocco
Glenn-Peter Sætre og Jørn H. Hurum
paleontologi anatomi plesiosaur gylogeni kladistikk
A Moroccan polycotylid plesiosaur from the early Turonian (Upper Cretaceous) of the Goulmima Formation is described. The specimen, bought from an American fossil dealer in 2002 by the Museum of Natural History, Oslo, is a nearly complete skull of an unknown species. It is compared to the holotypes of Thililua longicollis Bardet et al. 2003 and Manemergus anguirostris Buchy et al. 2005, both from the same formation, to investigate the phylogenetic relationship between the three specimens. A phylogenetic analysis and ordinance tests suggest that they are very closely related; still they display enough important morphological differences to signify that the Oslo specimen is different enough from the two other species to warrant a further investigation and description as a new species.
2013-03-12
2013-03-12
2007
2007-06-11
2007-09-25
Master thesis
Ronander, Patrick. A description and phylogenetic relationship of a polycotylid plesiosaur (Reptilia: Sauropterygia) from the Upper Cretaceous (Turonian) of Goulmima, Morocco. Masteroppgave, University of Oslo, 2007
http://hdl.handle.net/10852/11778
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Ronander, Patrick&rft.title=A description and phylogenetic relationship of a polycotylid plesiosaur (Reptilia: Sauropterygia) from the Upper Cretaceous (Turonian) of Goulmima, Morocco&rft.inst=University of Oslo&rft.date=2007&rft.degree=Masteroppgave
URN:NBN:no-16016
62211
071337938
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11778/2/ronander_oppgave.pdf
eng
oai:www.duo.uio.no:10852/11760
2017-12-07T12:58:31Z
com_10852_22
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Epirrita autumnata (Lepidoptera, Geometridae): one diverse species or a complex of several cryptic species?
Arild Johnsen, Jan T. Lifjeld og Leif Aarvik
Preliminary results from DNA-barcoding of Scandinavian butterflies and moths show high intraspecific sequence differences in the Autumnal moth, E. autumnata. One theory that might explain this finding is that E. autumnata comprises of several cryptic species. In this study, Epirrita samples from different locations in Norway, and some samples from Finland and Scotland were investigated, hoping to resolve the discrepancy found between mtDNA divergence and present division to species. The Small Autumnal moth, Epirrita filigrammaria, which is presumed to be endemic to Great Britain, was also examined because there is some suspicion of E. filigrammaria being an upland ecotype of the circumpolar E. autumnata. Sequencing of the mitochondrial region COI, as well as the nuclear regions ITS2 and Wingless, was performed. Genital preparations were made to see if morphological examinations supported the results from the molecular analysis. The results from genetic and morphological analysis showed no discrimination between E. autumnata and E. filigrammaria and support the theory of E. filigrammaria being an ecotype of E. autumnata. Results from sequencing the COI region suggest five different subgroups within the E. autumnata complex, and with no geographical structure. Sequencing of the nuclear markers and the morphological examinations shows little to no variation, and gives no indications of E. autumnata comprising of more than one species. As parasitic endosymbionts like Wolbachia is common in arthropods, all samples were sequenced with WSP primers. These results showed that several samples examined in this study were infected with Wolbachia, and with different strains corresponding to two of the mtDNA haplotypes found within E. autumnata. This might indicate indirect selection/selective sweeps on haplotypes. From these findings, a likely explanation for the high variation found within E. autumnata mtDNA is that variation arisen in allopatry, has at least partially been maintained by selective sweeps from multiple Wolbachia infections.
2013-03-12
2010
2010-11-24
2011-03-04
10000-01-0
Master thesis
Kvie, Kjersti Sternang. Epirrita autumnata (Lepidoptera, Geometridae): one diverse species or a complex of several cryptic species?. Masteroppgave, University of Oslo, 2010
http://hdl.handle.net/10852/11760
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Kvie, Kjersti Sternang&rft.title=Epirrita autumnata (Lepidoptera, Geometridae): one diverse species or a complex of several cryptic species?&rft.inst=University of Oslo&rft.date=2010&rft.degree=Masteroppgave
URN:NBN:no-26419
108685
11109657x
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11760/2/Oppgaven.pdf
eng
Dette dokumentet er ikke elektronisk tilgjengelig etter ønske fra forfatter. Tilgangskode/Access code A
forever
closedaccess
oai:www.duo.uio.no:10852/11758
2014-12-26T05:05:46Z
com_10852_22
com_10852_1
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Multilocus DNA sequencing of a widely distributed wood-inhabiting fungus reveals two main lineages with overlapping ranges in Europe: do hybrids occur?
Trichaptum fuscoviolaceum is a saprotrophic basidiomycete morphospecies growing on conifers. In the present study, the genetic structure in a circumboreal sample of T. fuscoviolaceum was analyzed using a multilocus sequencing approach. The analyses revealed a complex phylogeographic structure where two main lineages occurred; one European connected to Pinus and another circumboreal group connected to various coniferous hosts. The European group may have resided in South European refugia during the last glaciation followed by a northward range expansion. The circumboreal group probably have migrated into Europe from northeast. In Europe, in areas where the two main lineages occur in sympatry, some specimens possess heterozygous sequences, apparently because allelic versions from both lineages co-exist in the same dikaryons. The presence of alleles from both groups in the same individuals may reflect hybridization as a result of secondary contact between the two main groups. Additional data are needed to conclude whether the two main lineages represent cryptic species. The observed phylogeographic pattern resembles the pattern observed in other wood-inhabiting fungi, which could indicate that general phylogeographic trends exist across species.
2013-03-12
2013-03-12
2010
2010-08-20
2011-03-08
Master thesis
Fossdal, Renate M. Multilocus DNA sequencing of a widely distributed wood-inhabiting fungus reveals two main lineages with overlapping ranges in Europe: do hybrids occur?. Masteroppgave, University of Oslo, 2010
http://hdl.handle.net/10852/11758
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Fossdal, Renate M&rft.title=Multilocus DNA sequencing of a widely distributed wood-inhabiting fungus reveals two main lineages with overlapping ranges in Europe: do hybrids occur?&rft.inst=University of Oslo&rft.date=2010&rft.degree=Masteroppgave
URN:NBN:no-25445
104790
111965195
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11758/1/Renate_final.pdf
eng
oai:www.duo.uio.no:10852/11789
2017-12-07T12:58:31Z
com_10852_22
com_10852_1
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Population differences in early development in grayling (Thymallus thymallus) : a common garden experiment
Leif Asbjørn Vøllestad
harr ferskvannsfisk adaptiv evolusjon livshistoriestrategi reaksjonsnormer
Following colonization of new habitats and subsequent strong selection, adaptation to environmental conditions might be expected to be rapid. In a mountainous lake in Norway, Lesjaskogsvatnet, more than 20 distinct spawning demes of grayling have been established since the lake was colonized, less than 25 generations ago. The demes spawn in tributaries consistently exhibiting either cold or warm temperature conditions. I conducted a common garden experiment to investigate if differences in early developmental characters had been established between four demes in response to the different nursery environments the grayling embryos and larvae experience. Different subsets of individuals from the four demes were subjected to three different treatment temperatures to test for temperature effects. Traits related to timing of development (i.e. eye pigmentation and hatching) as well as growth and energy consumption (i.e. length and yolk sack size) were measured for individuals from daily samples from all demes in all temperatures. I found no differences in the timing of early developmental traits. However, traits related to larval growth and energy consumption showed significant variation. Such variation most likely reflects genetic differences; however the observed variation did not unambiguously correspond with predictions of countergradient variation or local adaptation. I conclude that the observed differences in growth related traits between demes are most probably a result of both directional and random processes influencing evolutionary change.
2013-03-12
2013-03-12
2009
2009-06-22
2009-07-08
Master thesis
Thomassen, Gaute. Population differences in early development in grayling (Thymallus thymallus) . Masteroppgave, University of Oslo, 2009
http://hdl.handle.net/10852/11789
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Thomassen, Gaute&rft.title=Population differences in early development in grayling (Thymallus thymallus) &rft.inst=University of Oslo&rft.date=2009&rft.degree=Masteroppgave
URN:NBN:no-22279
92982
092772013
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11789/2/ThomassenG_Master.pdf
eng
oai:www.duo.uio.no:10852/11793
2014-12-26T05:05:46Z
com_10852_22
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A phylogeographic survey of a circumboreal polypore indicates introgression among ecologically differentiated lineages
Håvard Kauserud, Tor Carlsen, Glenn-Peter Sætre
fylogeografi sopp mycologi artsdannelse vertsspesifisitet
Gloeoporus taxicola is a widespread saprotrophic polypore that occurs on a variety of coniferous substrates in the Northern Hemisphere. In this master thesis a multi-locus sequencing approach was used, on an extensive worldwide sample, to investigate the phylogepgraphy of G. taxicola in the light of substrate affinity. Diplophase sequences from
two nuclear markers gave a complex phylogeographic pattern that roughly divided the specimens into two evolutionary lineages, but some admixed and highly heterozygous sequences appeared as well. To increase the resolution, cloning was performed and haplophase sequences obtained. This revealed three main clusters of haplotypes, one representing a European lineage associated with pine, while the other two had more northern circumboreal distributions, occurring on a wide number of substrates. Some specimens contained two highly divergent haplophase sequences, probably reflecting hybridization and
further introgression between the separate evolutionary lineages. There was a strong indication of different host affinity between the two evolutionary lineages and one of the main lineages showed rather strong host specificity for a saprobic fungus. This study demonstrates
the importance of splitting heterozygous diplophase sequences into its underlying haplophase sequences to obtain a more comprehensive resolution in phylogeographic studies.
2013-03-12
2009
2010-01-13
2010-02-18
10000-01-0
Master thesis
Seierstad, Kristian S.. A phylogeographic survey of a circumboreal polypore indicates introgression among ecologically differentiated lineages. Masteroppgave, University of Oslo, 2009
http://hdl.handle.net/10852/11793
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Seierstad, Kristian S.&rft.title=A phylogeographic survey of a circumboreal polypore indicates introgression among ecologically differentiated lineages&rft.inst=University of Oslo&rft.date=2009&rft.degree=Masteroppgave
URN:NBN:no-24122
98495
092521819
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11793/1/SeierstadxMasterxThesis.pdf
eng
Dette dokumentet er ikke elektronisk tilgjengelig etter ønske fra forfatter. Tilgangskode/Access code A
forever
closedaccess
oai:www.duo.uio.no:10852/11759
2014-12-26T05:05:46Z
com_10852_22
com_10852_1
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Microsatellite heterozygosity and phenotypic quality in bluethroats (Luscinia svecica)
Arild Johnsen og Jan T. Lifjeld
zoologi biosystematikk blåstrupe mikrosatellitter
2013-03-12
2013-03-12
2009
2010-10-05
2010-11-08
Master thesis
Herfoss, Anders Lunden. Microsatellite heterozygosity and phenotypic quality in bluethroats (Luscinia svecica). Masteroppgave, University of Oslo, 2009
http://hdl.handle.net/10852/11759
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Herfoss, Anders Lunden&rft.title=Microsatellite heterozygosity and phenotypic quality in bluethroats (Luscinia svecica)&rft.inst=University of Oslo&rft.date=2009&rft.degree=Masteroppgave
URN:NBN:no-26250
106030
102453039
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11759/1/master_herfoss.pdf
eng
oai:www.duo.uio.no:10852/11787
2014-12-26T05:05:46Z
com_10852_22
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Divergent foraging behaviour and shape in lateral plate morphs of threespined stickleback (Gasterosteus aculeatus).
Helene M. Lampe, Kjartan Østbye
stingsild form furasjering adferd
Adaptation to different foraging resources is believed to be an important driving force of divergence between populations. Following colonization of freshwater, threespined sticklebacks (Gasterosteus aculeatus) have occupied and adapted to different types of aquatic niches. Adaptation to freshwater often involves, among other things, loss of lateral plates, shift to benthic resource exploitation, and change in body shape. Here, divergence in foraging behaviour and body shape is investigated among different lateral plate morphs coexisting in brackish water, and in a monomorphic population from a river habitat. Foraging behaviour was tested experimentally in the lab by observing fish that were offered benthic and pelagic prey simultaneously, while tracking the movements of the fish automatically. Shape differences were characterized using geometric morphometric Thin plate spline analysis. Significant and corresponding differences in foraging behaviour and shape were found between the plate morphs, and between sticklebacks from river and the lake. The results indicate ecological divergence towards benthic and pelagic habitat use between the plate morphs, resembling that of coexisting benthic-pelagic species pairs. This further suggests a possibility for evolution of ecologically based reproductive barriers between the coexisting morphs, although this remains to be investigated in more detail.
2013-03-12
2013-03-12
2008
2008-08-13
2009-03-31
Master thesis
Bjærke, Oda. Divergent foraging behaviour and shape in lateral plate morphs of threespined stickleback (Gasterosteus aculeatus).. Masteroppgave, University of Oslo, 2008
http://hdl.handle.net/10852/11787
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Bjærke, Oda&rft.title=Divergent foraging behaviour and shape in lateral plate morphs of threespined stickleback (Gasterosteus aculeatus).&rft.inst=University of Oslo&rft.date=2008&rft.degree=Masteroppgave
URN:NBN:no-19903
82591
091896746
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11787/1/masteroda.pdf
eng
oai:www.duo.uio.no:10852/11782
2014-12-26T05:05:47Z
com_10852_22
com_10852_1
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Human mitochondrial DNA diversity in urban Cape Town
Erika Hagelberg
molekylær antropolgi DNA variasjon mitokondrial
Summary.
This work arose from a collaborative project between the University of Western Cape and the University of Oslo, funded by the Research Council of Norway. The original project was set up to identify informative Y-chromosomal markers for use in forensic casework in South Africa, after it was found that the standard Y-chromosome markers used in crime cases were not suited to the ethnically varied South African population. Appropriate markers are necessary not only to help convict criminals, but to exclude innocent people who happen to match a suspect by chance. This research became vital in a country with a long history of racial discrimination and human right abuses. Another purpose of the original project was to train South African scientists in bone DNA typing, to help identify the remains of political activists murdered during the Apartheid period.
Very little research has been carried out on the genetic composition of complex urban populations. In this master project I used mitochondrial DNA (mtDNA) to explore the present-day genetic makeup in Cape Town, South Africa, in the context of historical information. My study group consisted of a group of students from the University of Western Cape.
MtDNA is maternally inherited, with little or no recombination. This permits maternal genetic lineages to be traced back to a most recent common ancestor (MRCA). MtDNA exhibits population-specific polymorphisms. The mtDNA control region is subject to high mutation rate, which allows closely related groups to be studied. The high mutation rate can be used to infer the phylogeographical changes since our MRCA.
In this study, a high level of genetic diversity was observed. In the 48 individuals tested, 48 unique sequences were observed, representing thirty different mtDNA groups with origins in Africa, Eurasia, Southeast Asia, and the Indian subcontinent.
2013-03-12
2013-03-12
2007
2007-10-26
2007-11-09
Master thesis
Kaspersen, Vidar. Human mitochondrial DNA diversity in urban Cape Town. Masteroppgave, University of Oslo, 2007
http://hdl.handle.net/10852/11782
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Kaspersen, Vidar&rft.title=Human mitochondrial DNA diversity in urban Cape Town&rft.inst=University of Oslo&rft.date=2007&rft.degree=Masteroppgave
URN:NBN:no-16974
66776
071627235
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11782/1/MasterxVidarxCompletelyxCompleted1.pdf
eng
oai:www.duo.uio.no:10852/11783
2017-12-15T08:38:23Z
com_10852_22
com_10852_1
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Population growth and life history traits within the monogenean Gyrodactylus salaris and G. thymalli complex
Tor A. Bakke and Lutz Bachmann
zoologi lakseparasitten gyrodactylus salaris trekklivshistorie populasjonsvekst
Abstract
Up until now, there have not been many studies of single Gyrodactylus manipulations on salmonids performed in order to study the establishment, development and reproduction of the parasites. The results of the current thesis indicated a relatively marked ecological difference between Gyrodactylus salaris and G. thymalli with respect to host preference and population growth. However, a potential for co-occurrence of both species on the same host still exists. This study provides results from extensive infection attempts conducted on Norwegian Atlantic salmon (River Altaelva), Baltic salmon (River Neva) and grayling (River Trysilelva). All hosts were infected with G. salaris (both an Atlantic salmon and an Arctic charr strain) and G. thyamlli (River Trysilelva strain). The correlation between population growth of isolated salmon and grayling, and the survival and reproduction of the individual Gyrodactylus strains/species on different hosts, was studied. The results indicate that Norwegian Atlantic salmon are unlikely to be a functional host for the G. thymalli strain used in this study. Furthermore, the Arctic charr strain of G. salaris that was used for the first time to be infected onto grayling and could in contrast to on salmon successfully establish and give birth on grayling. This indicates that ecological host preferences are not reflected in the mitochondrial cytochrome oxidase I (COI) systematics. The Norwegian Atlantic salmon demonstrated variability in susceptibility and resistance to the pathogenic G. salaris strain. This was also observed for G. thymalli on grayling. The population reproductive rates (r) calculated for all parasite strains on the respective hosts showed a steady decline regardless of the initial parasite population size. This may reflect a fundamental process in gyrodactylid population biology, and the host may act against the parasite s presence or activity from the start of the infection. The comparison between theoretic and natural growth indicated that only G. salaris (Atlantic salmon strain) on Norwegian Atlantic salmon and G. thymalli on grayling followed the expected growth curves based on intrinsic rate of increase (rm) values, although for G. thymalli on grayling an acquired host immune reaction was noticed.
2013-03-12
2007
2007-12-19
2008-03-04
Master thesis
Øvstaas, Ole Gunnar. Population growth and life history traits within the monogenean Gyrodactylus salaris and G. thymalli complex. Masteroppgave, University of Oslo, 2007
http://hdl.handle.net/10852/11783
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Øvstaas, Ole Gunnar&rft.title=Population growth and life history traits within the monogenean Gyrodactylus salaris and G. thymalli complex&rft.inst=University of Oslo&rft.date=2007&rft.degree=Masteroppgave
URN:NBN:no-18655
69073
071859691
eng
oai:www.duo.uio.no:10852/11788
2017-12-07T12:58:31Z
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Phylogeograpy and population structure in Dryas octopetala L. analysed by microsatellite markers
Anne Krag Brysting, Håvard Kauserud, Inger Nordal, Marte Holten Jørgensen
fylogeografi botanikk reinrose mikrosatellitter
Dryas octopetala L. is an arctic-alpine plant that belongs to a genus where the number and delimitation of species are not fully resolved. The plant is unusual, compared with most other arctic-alpine plants in its diploid, dwarf-shrub habit with slow generation turnover. In this study, ten newly developed microsatellite markers have been tested and used to infer both phylogeography and population structure in 471 individuals of D. octopetala sampled from seven main localities in the North Atlantic area. In addition, the microsatellite markers were used to investigate whether there is genetic support for assigning three morphotypes of D. octopetala on Svalbard to taxa, as previously proposed by Russian scientists.
Nine of the ten microsatellites were analysed in this study, and provided a resolution high enough to distinguish between individuals. At a phylogeographic scale, the analysed material grouped into three main groups, a southern group, an intermediate group and a northernmost group. It is likely that there have been two main colonization routes following the glacial retreat in the North Atlantic region, one southern and one eastern. This study supports a colonization route from the south for the southern Norwegian populations, while an eastern immigration route probably has colonized Greenland, northern Norway and Svalbard.
At a smaller, population scale, the microsatellites separated between different genets of D. octopetala. The local D. octopetala populations were mainly in Hardy-Weinberg equilibrium and no latitudinal trend was found regarding the proportion of ramets in the sampled populations or for heterozygote deficiency.
No evidence for assigning the three morphotypes occurring on Svalbard to taxa was found, and thus this study concludes that there is only one Dryas species on Svalbard, i.e., D. octopetala.
2013-03-12
2013-03-12
2008
2009-01-05
2009-04-02
Master thesis
Vik, Unni. Phylogeograpy and population structure in Dryas octopetala L. analysed by microsatellite markers. Masteroppgave, University of Oslo, 2008
http://hdl.handle.net/10852/11788
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Vik, Unni&rft.title=Phylogeograpy and population structure in Dryas octopetala L. analysed by microsatellite markers&rft.inst=University of Oslo&rft.date=2008&rft.degree=Masteroppgave
URN:NBN:no-21070
88411
091916267
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11788/2/oppgxva.pdf
eng
oai:www.duo.uio.no:10852/11775
2017-12-07T12:58:32Z
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Tracing the evolutionary history of the Atlas flycatcher (Ficedula speculigera) : a molecular genetic approach
Glenn-Peter Sætre
biodiversitet atlasfluesnapper fluesnapper evolusjonær historie utvikslingshistorie artsdannelse multilocus sekvensanalyse
Abstract
The Atlas flycatcher (Ficedula speculigera) is a poorly studied species in an otherwise thoroughly studied species complex. In this study I attempt to reconstruct the evolutionary history of this species, I look for possible traces of introgression, I test whether there is contrasting patterns of polymorphism and divergence at autosomal and Z-linked genes as has been found in other flycatcher species, and finally whether the Atlas flycatcher show reduced genetic variation which would be expected due to recent habitat fragmentation. To address these problems I used multilocus sequence analysis, with loci from both autosomes and Z-chromosomes, and compared these with previously published sequences from two other species, the pied flycatcher (F. hypoleuca) and the collared flycatcher (F. albicollis). Finally, phenotypic measures of the Atlas flycatcher were compared with measures of these other two species. The results appear consistent with a scenario in which an ancestral flycatcher species became isolated in different refugia, presumably around the Mediterranean Sea, at the onset of the Pleistocene glaciations and diverged into the present species. I found no traces of introgression between the Atlas flycatcher and any of the two other species. Further, the Atlas flycatcher showed reduced variation at Z-linked loci compared to autosomal loci, which may indicate a complex demographic history or possibly selection. The Atlas flycatcher also showed high variation compared to the other two species, and therefore seems to have a rather large effective population size.
2013-03-12
2013-03-12
2007
2007-04-15
2007-05-04
Master thesis
Bruvik, Torbjørn. Tracing the evolutionary history of the Atlas flycatcher (Ficedula speculigera) . Masteroppgave, University of Oslo, 2007
http://hdl.handle.net/10852/11775
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Bruvik, Torbjørn&rft.title=Tracing the evolutionary history of the Atlas flycatcher (Ficedula speculigera) &rft.inst=University of Oslo&rft.date=2007&rft.degree=Masteroppgave
URN:NBN:no-14868
56289
070652554
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11775/1/MasteroppgaveTorbjornBruvik.pdf
eng
oai:www.duo.uio.no:10852/11791
2014-12-26T05:05:47Z
com_10852_22
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A study of the hybrid zone between house sparrow (Passer domesticus) and Italian sparrow (Passer italiae) based on plumage characters and microsatellites
Glenn-Peter Sætre
2013-03-12
2009
2009-09-22
2009-09-22
10000-01-0
Master thesis
Hjelle, Elin. A study of the hybrid zone between house sparrow (Passer domesticus) and Italian sparrow (Passer italiae) based on plumage characters and microsatellites. Masteroppgave, University of Oslo, 2009
http://hdl.handle.net/10852/11791
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Hjelle, Elin&rft.title=A study of the hybrid zone between house sparrow (Passer domesticus) and Italian sparrow (Passer italiae) based on plumage characters and microsatellites&rft.inst=University of Oslo&rft.date=2009&rft.degree=Masteroppgave
URN:NBN:no-23220
94992
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11791/1/masterxthesis.pdf
eng
Dette dokumentet er ikke elektronisk tilgjengelig etter ønske fra forfatter. Tilgangskode/Access code A
forever
closedaccess
oai:www.duo.uio.no:10852/11768
2014-12-26T05:05:47Z
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Recurrent origins and adaptive advantage of polyploid Parnassia palustris
Anne Krag Brysting, Aud Berglien Eriksen, Marte Holten Jørgensen
Polyploidi er en sentral drivkraft for evolusjon hos dekkfrøede planter, og polyploide linjer er spesielt tallrike i arktiske strøk. I denne studien undersøkte jeg di- og tetraploide populasjoner av arten Jåblom, Parnassia palustris, som har divergerende distribusjon i Fennoskandia. Ved å bruke AFLP som genetiske markører fant jeg ut at arten har kolonisert Fennoskandia fra minst to refugier etter at isen trakk seg tilbake etter siste istid. Den høye genetiske diversiteten jeg fant i Fennoskandiske populasjoner kan være resultatet av slik sekundær kontakt mellom populasjoner som har vært isolerte fra hverandre under sist istid. Genetiske analyser viste at det er sannsynlig at tetraploidene i Europa har oppstått flere ganger, og/eller at genflyt har skjedd mellom di- og tetraploider. De molekylære analysene gir ikke grunnlag for å separere di- og tetraploidene i to linjer. Et veksteksperiment viste at forskjell mellom individer i overlevelse og vekst ikke kunne knyttes til polyploidi per se.
Background and aims: Polyploidy is a major driving force behind angiosperm evolution. The distribution of polyploid taxa has lead previous authors to suggest a connection between such genome duplication and major climatic events, like glaciations. In this study, European di- and tetraploid Parnassia palustris were used to explore how the genetic structure and distribution of the cytotypes relates to the glacial history of the study area, to evaluate the taxonomic treatment of the cytotypes, to search for evidence for interploidal gene flow and/or recurrent formation of the tetraploid, and to explore differences in ecological flexibility between cytotypes.
Material and methods: Flow cytometry and AFLP were used to find ploidal levels and genetic structure. Growth experiments were performed in search for effects of ploidy on growth and survival during various day lengths and temperature treatments, and analysed employing Generalised Linear Models and Survival analyses.
Results: Tetraploid populations were recorded from the Alps for the first time, and triploids were detected in areas where diploid and tetraploid populations are sympatric. Ploidal levels explained little of the genetic variation, and di- and tetraploid sympatric populations were genetically similar. High levels of genetic diversity were found in Fennoscandian populations. According to GLMs and survival analyses, survival was the only out of several fitness measures that was significantly affected by ploidy. High temperatures resulted in lower tetraploid survival.
Conclusions: Tetraploids are mainly distributed in previously glaciated areas, and taxonomic rank for the tetraploid cytotype could not be supported. Immigration from at least two refugia probably met in a contact zone in Fennoscandia, resulting in high levels of genetic diversity. Gene flow between the cytotypes and/or recurrent origins of the tetraploid are probable processes. No differences in ecological flexibility could be attributed to polyploidy per se.
2013-03-12
2013-03-12
2011
2012-02-16
2012-04-20
Master thesis
Bjørgaas, Hanna Hagen. Recurrent origins and adaptive advantage of polyploid Parnassia palustris. Masteroppgave, University of Oslo, 2011
http://hdl.handle.net/10852/11768
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Bjørgaas, Hanna Hagen&rft.title=Recurrent origins and adaptive advantage of polyploid Parnassia palustris&rft.inst=University of Oslo&rft.date=2011&rft.degree=Masteroppgave
URN:NBN:no-30573
151575
121259846
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11768/1/Master_thesis_HB.pdf
eng
oai:www.duo.uio.no:10852/11776
2014-12-26T05:05:47Z
com_10852_22
com_10852_1
col_10852_28
Polyploidy in Daphnia : methodology and effects on life history traits
Dag O. Hessen, Morten M. Laane
polyploidi Daphnia arktis livshistorie strategier
Four arctic, obligate parthenogenetic populations assumed to be polyploid and one temperate, cyclic parthenogenetic, diploid population were used to compare life history traits, growth rates and content of nucleic acids for polyploidy versus diploidy. Cytogenetic studies were done to evaluate the level of ploidy optically or with the aid of optical instruments. A life history experiment was run to identify variations in fitness parameters, fertility, maturation, growth and survival, identifying the adaptive effects and costs of polyploidy. Variations in nucleic acids in polyploids and diploids were accessed by quantifying DNA, RNA and protein. A microsatellite analysis was run to verify the assumed ploidy levels, and species identification was done by sequencing mtDNA and comparing with previously published sequences. The study has a strong focus on assessment of different methods and is in structure affected by this.
Microsatellite analysis positively identified the arctic populations as polyploids, and the temperate as diploid. No assessment of the chromosome numbers was reached using cytogenetic analyses. Statistical difference was noted between the nuclei size in the intestine and connective tissue between the diploid and polyploid populations. Polyploid populations were found to have lower population growth, lower fertility, smaller size and delayed maturation, lower growth rate and lower survival than the diploid population. Ploidy level and quantity of nucleic levels and ratios were not found to be correlated, but RNA and DNA per dry weight and RNA/DNA ratio was found to be weakly correlated with specific growth rate when controlled for the ploidy levels.
2013-03-12
2013-03-12
2007
2007-06-07
2007-07-10
Master thesis
Alfsnes, Kristian. Polyploidy in Daphnia. Masteroppgave, University of Oslo, 2007
http://hdl.handle.net/10852/11776
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Alfsnes, Kristian&rft.title=Polyploidy in Daphnia&rft.inst=University of Oslo&rft.date=2007&rft.degree=Masteroppgave
URN:NBN:no-15168
61909
070972435
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11776/1/FerdigxMaster.pdf
eng
oai:www.duo.uio.no:10852/11784
2017-12-15T08:38:46Z
com_10852_22
com_10852_1
col_10852_28
Genetic variation in Holocene Spitsbergen stock bowhead whales inferred from mitochondrial cytochrome B gene sequences amplified from ancient DNA
Lutz Bachmann, Øystein Wiig
zoologi grønlandshval forhistorisk DNA genetisk variasjon hval
The control region (CR) of the mitochondrial DNA has been previously used to decipher the population structure of Holocene bowhead whales (Balaena mysticetus) from the Spitsbergen stock. The bone samples dated from recent to more than 50000 years BP were collected on the elevated beaches of Svalbard, and are related to ancestors of the nearly extinct Spitsbergen stock. Very high haplotype diversity was reported that frequency based analyses and comparisons with other data set became meaningless; More than 80 % of the specimens had individual specific haplotypes. Therefore, it was of large interest to investigate the genetic variation in a mitochondrial marker expected to contain less variation. In the present project the mitochondrial cytochrome b gene was successfully sequenced for 33 of the historic bowhead whale samples. As expected, haplotype and nucleotide diversity based on the cytB was significantly lower rendering this gene a suitable marker for genetic comparisons of bowhead whale stocks. However, cytB sequences did not allow to identify groups of control region based haplotypes.
2013-03-12
2008
2008-02-18
2008-03-04
Master thesis
Meland, Tina. Genetic variation in Holocene Spitsbergen stock bowhead whales inferred from mitochondrial cytochrome B gene sequences amplified from ancient DNA . Masteroppgave, University of Oslo, 2008
http://hdl.handle.net/10852/11784
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Meland, Tina&rft.title=Genetic variation in Holocene Spitsbergen stock bowhead whales inferred from mitochondrial cytochrome B gene sequences amplified from ancient DNA &rft.inst=University of Oslo&rft.date=2008&rft.degree=Masteroppgave
URN:NBN:no-18659
70411
080258026
eng
oai:www.duo.uio.no:10852/11763
2014-12-26T05:05:47Z
com_10852_22
com_10852_1
col_10852_28
Diversity and species composition of fungal endophytes in Avenella flexuosa under different sheep grazing regimes
Håvard Kauserud, Tor Carlsen, Atle Mysterud, Trude Vrålstad
Fungal endophytes have been shown to be extremely widespread and abundant in terrestrial plants. It is also known that fungal endophytes may affect the grazing intensity of the host plant. In this study the occurrence of fungal endophytes in the perennial grass Avenella flexuosa was investigated under different grazing regimes in a field site in Norway. The main aim was to reveal to what degree the grazing influenced the fungal diversity and species composition. The fungal endophytes were analyzed using both culturing coupled to Sanger sequencing as well as 454 sequencing. The ITS2 rDNA region was used as a fungal DNA barcode. Based on the 454 data, a higher number of fungi were detected in stems of grazed compared to non-grazed plants. However, no significant difference was observed in the inflorescences and leaves. A distinct difference in fungal community composition was observed between leaves, stems and inflorescences. Apparently, the fungal community composition varied more in non-grazed compared to grazed plants. Saturation curve analyses indicated that most fungi remained undetected. Noteworthy, a high discrepancy was observed between the two methods, both in OTU number and overlap. From the 37 and 896 operational taxonomic units obtained from cultivation and 454 sequencing respectively. Only three OTUs were recovered by both methods. No known toxin producing endophytes were detected in A. flexuosa. Instead, Phaeosphaeria/Stagonospora spp. dominated both culture and 454 data, constituting potentially biological important endophytes of this grass. Intriguingly, various basidio-yeasts with high prevalence in the 454 dataset were not recovered by cultivation. This study indicates that grazing may have some influence on the diversity and composition of fungal endophytes. However, the different approaches underlines that the results must be interpreted with great care since there are many potential biases inherent both with the culturing and the 454 sequencing approach.
2013-03-12
2013-03-12
2010
2011-02-23
2011-03-08
Master thesis
Aas, Anders Bjørnsgard. Diversity and species composition of fungal endophytes in Avenella flexuosa under different sheep grazing regimes. Masteroppgave, University of Oslo, 2010
http://hdl.handle.net/10852/11763
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Aas, Anders Bjørnsgard&rft.title=Diversity and species composition of fungal endophytes in Avenella flexuosa under different sheep grazing regimes&rft.inst=University of Oslo&rft.date=2010&rft.degree=Masteroppgave
URN:NBN:no-27072
112535
111965306
Fulltext https://www.duo.uio.no/bitstream/handle/10852/11763/1/Masterxoppg.pdf
eng
oai:www.duo.uio.no:10852/34176
2014-12-26T05:11:43Z
com_10852_22
com_10852_1
col_10852_28
The enigmatic Bale monkey: can new analyses shed light on the phylogeny of the Chlorocebus genus?
Anne Krag Brysting, Eli Knispel Rueness, Nils Christian Stenseth
Bale-apen (Chlorocebus djamdjamensis) er en lite kjent, endemisk primat fra det etiopiske høylandet. Apen er klassifisert som "Vulnerable" under IUCNs Rødliste for truede arter, og er truet av et stadig økende antropogent press.
Mangelen på informasjon tilgjengelig om denne arter, i tillegg til dens status som truet, gjør behovet for mer kunnskap prekært.
Slekten Chlorocebus består av flere morfologisk like arter, og den korrekte identifiseringen av disse har vært en utfordring for taksonomer. Klassifiseringen av artene i slekten har blitt videre komplisert av den tilsynelatende hyppige hybridiseringen mellom Chlorocebus-apene. Slektens taksonomi har vært debattert i over et århundre, men mangel på molekylære data for Bale-apen har gjort det vanskelig å avgjøre dens plassering innen Chlorocebus som en art eller en underart. Hittil har ingen molekylære fylogenier som inkluderer denne arten blitt produsert.
I dette studiet ble mitokondrielle markører benyttet til å undersøke det fylogenetiske forholdet mellom fem av de seks artene i Chlorocebus-slekten. Genene 12S, COI og cyt b ble benyttet til å produsere tre ulike topologier. Topologiene var i hovedsak overensstemmende, men ingen av artene i inngruppen dannet monofyletiske grupper. Isteden ble individer antatt å være ulike arter gruppert sammen - et resultat som tyder på mulig feilidentifisering av individer grunnet kryptisk variasjon. Tilgjengelige nukleære markører, nødvendig for å løse fylogenien fullstendig dersom hybridisering er inne i bildet, viste ikke tilstrekkelig variasjon, og ble derfor utelatt fra videre analyser. Grunnet mangelen på nukleære data er det vanskelig å avgjøre hvorvidt hybridisering har funnet sted mellom individene i dette studiet, og å inferere Bale-apens taksonomiske status. Alternative forklaringer for uoverensstemmelsen sett i fylogenien legges likevel frem, og diskuteres på bakgrunn av tilleggsinformasjon om individenes morfologi og geografiske opprinnelse.
The Bale monkey (Chlorocebus djamdjamensis) is a little known primate endemic to the Ethiopian highlands. It is classified as ‘Vulnerable’ in the IUCN Red List of Threatened Species, and is under threat from increasing anthropogenic pressure. The lack of information about the Bale monkey combined with its threatened status stresses the need for more knowledge. The Chlorocebus genus consists of several morphologically similar species, and the correct identification of these has been a challenge for taxonomists. Furthermore, the classification of the species in the genus has become even more complicated because of the apparent frequent hybridization between the Chlorocebus monkeys.The taxonomy of the genus has been debated for over a century, but lack of molecular data on the Bale monkey has made it difficult to determine its placement within Chlorocebus as a species or a subspecies. Until now, no molecular phylogenies including the Bale monkey have been produced. In this study, mitochondrial markers have been used to investigate the phylogenetic relationship between five of the six species in the Chlorocebus genus, using the 12S, COI and cyt b genes to produce three different topologies. The topologies were mainly congruent, but none of the species in the ingroup formed monophyletic clades. Instead, individuals thought to be different species grouped together, pointing towards possible misidentification of individuals because of cryptic variation. Nuclear markers, which would be necessary to resolve the phylogeny completely if hybridization is involved, did not show sufficient variation, and were therefore left out of further analyses. Because of the lack of nuclear data, it is difficult to conclude whether hybridization has taken place between the individuals in this study, and to infer the taxonomic status of the Bale monkey. However, alternative explanations for the incongruence seen in the phylogeny are put forward and discussed based on additional information on the morphology and geographic origin of the sampled individuals.
2013-08-01
2013-08-01
2012
2012-11-12
2013-07-11
Master thesis
Bjørnæs, Ane Mari. The enigmatic Bale monkey: can new analyses shed light on the phylogeny of the Chlorocebus genus? . Masteroppgave, University of Oslo, 2012
http://hdl.handle.net/10852/34176
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Bjørnæs, Ane Mari&rft.title=The enigmatic Bale monkey: can new analyses shed light on the phylogeny of the Chlorocebus genus? &rft.inst=University of Oslo&rft.date=2012&rft.degree=Masteroppgave
URN:NBN:no-32888
172161
132332965
Fulltext https://www.duo.uio.no/bitstream/handle/10852/34176/1/Bjoernaes-Master.pdf
nob
oai:www.duo.uio.no:10852/36739
2014-12-26T05:11:20Z
com_10852_22
com_10852_1
col_10852_28
Conservation genetics and ecology of four red listed vascular plant species in the high arctic archipelago of Svalbard
Inger Greve Alsos, Anne Krag Brysting
Nearly one third of the vascular plant species of the remote high arctic archipelago of Svalbard are listed on the regional Red List for Svalbard, and there is a need for information to evaluate their conservation status, and improve conservation management. Here I study distribution, population sizes, ecology, and threats in Carex capillaris, Comastoma tenellum, Puccinellia angustata ssp. palibinii, and Tofieldia pusilla which are all restricted to some of the warmest local areas of Svalbard. Further, I use Amplified Fragment Length Polymorphism (AFLP) to evaluate whether the Svalbard populations are genetically depleted compared to other arctic-alpine populations of the species, investigate their phylogeographic history, and resolve taxonomic problems. All species have larger populations than previously assumed and new populations of C. tenellum and T. pusilla were discovered. Carex capillaris is thriving, and is associated with high substrate moisture and temperature at its only Svalbard locality. Local expansion potential was indicated. The population is genetically depleted, and forms a distinct genetic subgroup of ssp. fuscidula, with N Norway as the most likely source region. The results indicate that C. capillaris may have colonized Svalbard during the warmer early-middle Holocene, but a more recent introduction is also possible. Possible threats include reduced evolutionary potential, inbreeding depression, and stochastic events. Comastoma tenellum is growing in bird cliff vegetation at its three known localities. The populations are genetically depleted, and although clearly related to the most probable source region, NW Russia, they form a distinct genetic subgroup. This suggests an early-middle Holocene introduction of the species to Svalbard, associated with a strong founder effect. Possible threats include reduced evolutionary potential, inbreeding depression, and fluctuating population sizes. The population of P. angustata ssp. palibinii in Bockfjorden has been erroneously classified and belongs to the Svalbard endemic P. svalbardensis. This species exhibits a highly specialized ecology and is locally abundant in other parts of Svalbard. High levels of genetic diversity were detected, and no genetic threats are apparent. Tofieldia pusilla is found in different types of habitats, but temperature might restrict local expansion. The populations are not notably genetically depleted, which indicates that T. pusilla is doing comparatively better than many other thermophilous vascular plants in Svalbard. Based on the results, C. capillaris and C. tenellum were downgraded to less critical Red List categories, and T. pusilla was taken out of the Red List. As temperature probably is the limiting factor to C. capillaris, C. tenellum and T. pusilla in Svalbard, they are expected to benefit from a warmer climate.
2013-08-29
2013-08-29
2012
2013-08-13
2013-08-28
Master thesis
Skjetne, Idunn Elisabeth. Conservation genetics and ecology of four red listed vascular plant species in the high arctic archipelago of Svalbard. Masteroppgave, University of Oslo, 2012
http://hdl.handle.net/10852/36739
info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Skjetne, Idunn Elisabeth&rft.title=Conservation genetics and ecology of four red listed vascular plant species in the high arctic archipelago of Svalbard&rft.inst=University of Oslo&rft.date=2012&rft.degree=Masteroppgave
URN:NBN:no-37325
184061
Fulltext https://www.duo.uio.no/bitstream/handle/10852/36739/1/Skjetne_Master_final.pdf
eng