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

Stilmanér i paleontologiska illustrationer : Examensarbete i informativ illustration

Rudebjer, Stina January 2019 (has links)
Bland paleontoligifokuserad media riktad till barn så är dinosaurier väldigt överrepresenterade, och utifrån mina observationer så är kunskapen om andra förhistoriska arter därför låg. Därför så har jag skapat ett koncept för en paleontologisk barnbok om icke-dinosaurier, och bokens illustrationer har anpassats efter målgruppens behov. För att ta reda på vilken stil som är bäst lämpad för ämnet så har jag genomfört tester, genomfört intervjuer och granskat tidigare paleontologiskt material. Detta har lett mig till slutsatsen att stiliserade men samtidigt faktamässigt korrekta och icke-abstrakta illustrationer är den bäst lämpade stilen för faktaböcker om paleontologi riktade till barn i mellanstadieålder. Denna kunskap kan var till nytta för att skapa böcker med information som målgruppen tar åt sig av, och det kan även vara mer ekonomiskt i och med att stiliserade illustrationer går fortare att producera.   Nyckelord: Illustration, paleontologi, pedagogik, barnläromedel / Among paleontology-focused media aimed at children, dinosaurs are really overrepresentated, and based on my observations, the knowledge of other prehistoric species are low. Because of this, I’ve created a concept for a paleontologic children’s book about non-dinosaurs, with illustrations that are adapted for the needs of the target audience. To find out what style is the best suited for the subject, I’ve performed tests and interviews and analysed earlier paleontologic material. This has led me to the conclusion that stylised but still factual and non-abstract illustrations are the most well-suited style for factual literature about paleontology aimed at the target audience, middle school-aged children. This knowledge can be useful for creating books that the target audience are likely to absorb, and it can also be more economic since stylised illustrations is quicker to produce.   Keywords: Illustration, paleontology, pedagogy, children’s factual litterature
2

The late Ediacaran Agglutinated Foraminifera from Finnmark, Northern Norway

Pazio, Magdalena January 2012 (has links)
No description available.
3

Evolution and taxonomy of Cambrian arthropods from Greenland and Sweden

Stein, Martin January 2008 (has links)
<p>Arthropods have a rich fossil record spanning the Phanerozoic. Biomineralized forms such as the extinct trilobites are particularly common and are proven index fossils for biostratigraphy. Forms with an unmineralized cuticle are more rare, preserved only in so called <i>konservat lagerstätten</i>. Cambrian strata of Greenland have yielded rich trilobite faunas with potential for intercontinental correlation of Cambrian strata, but also an exceptionally preserved fauna, the Sirius Passet Lagerstätte. The first part of this thesis is concerned with trilobite biotratigraphy of the provisional Cambrian Series 2 in Greenland. The second part is concerned with exceptionally preserved arthropods from the Sirius Passet Lagerstätte, but also from 'Orsten' deposits from the Cambrian of Sweden.</p><p><i>Perissopyge phenax occurs</i> in the Henson Gletscher and Paralleldal formations spanning the Series 2 and 3 boundary interval in North Greenland. It also occurs in the Sekwi Formation of Yukon Territory, demonstrating that the species may hold potential for correlation within Laurentia. An indeterminate species of <i>Perissopyge</i> is shown to occur in the Ella Island Formation of North-East Greenland together with <i>Olenellus</i> cf. <i>hanseni</i>, which is similar to <i>Olenellus</i> cf. <i>truemani</i> described from the Henson Gletscher Formation. If this correlation is further corroborated it would offer a first tie-point for the An t'Sron Formation of North-West Scotland which yields <i>Fritzolenellus</i> <i>lapworthi</i>, herein reported for the first time from the Bastion Formation which underlies the Ella Island Formation.</p><p><i>Oelandocaris</i> <i>oelandica</i> from ‘Orsten’ deposits in the Cambrian series 3 and 4 boundary interval in Sweden is an early representative of the Crustacean stem lineage. <i>Kiisortoqia</i> <i>avannaarsuensis</i> is a new arthropod from the Sirius Passet Lagerstätte with robust antennulae strikingly similar to the 'raptorial' limb of the problematic anomalocaridids. The ventral morphology of the 'bivalved' <i>Isoxys</i> <i>volucris</i> is described for the first time and compared with other species assigned to <i>Isoxys</i> from Cambrian lagerstätten around the world. Finally, <i>Siriocaris</i> <i>trolla</i>, is a new arthropod that similarities with trilobites and certain ‘trilobitomorphs’ but seems to lack important synapomorphies of these taxa, though this may be due to preservational limitations in the material at hand.</p>
4

The morphology and evolutionary significance of the anomalocaridids

Daley, Allison C. January 2010 (has links)
Approximately 600 to 500 million years ago, a major evolutionary radiation called the “Cambrian Explosion” gave rise to nearly all of the major animal phyla known today. This radiation is recorded by various fossil lagerstätten, such as the Burgess Shale in Canada, where soft-bodied animals are preserved in exquisite detail. Many Cambrian fossils are enigmatic forms that are morphologically dissimilar to their modern descendants, but which still provide valuable information when interpreted as stem-group taxa because they record the actual progression of evolution and give insight into the order of character acquisitions and homologies between living taxa. One such group of fossils is the anomalocaridids, large presumed predators that have had a complicated history of description. Their body has a trunk with a series of lateral lobes and associated gills, and a cephalic region with a pair of large frontal appendages, a circular mouth apparatus, stalked eyes and a cephalic carapace. Originally, two taxa were described from the Burgess Shale, Anomalocaris and Laggania, however data presented herein suggests that the diversity of the anomalocaridids was much higher. Newly collected fossil material revealed that a third Burgess Shale anomalocaridid, Hurdia, is known from whole-body specimens and study of its morphology has helped to clarify the morphology and systematics of the whole group. Hurdia is distinguished by having mouthparts with extra rows of teeth, a unique frontal appendage, and a large frontal carapace. Two species, Hurdia victoria and Hurdia triangulata were distinguished based on morphometric shape analysis of the frontal carapace. A phylogenetic analysis placed the anomalocaridids in the stem lineage to the euarthropods, and examination of Hurdia’s well-preserved gills confirm the homology of this structure with the outer branches of limbs in upper stem-group arthropods. This homology supports the theory that the Cambrian biramous limb formed by the fusion of a uniramous walking limb with a lateral lobe structure bearing gill blades. In this context, new evidence is present on the closely allied taxon Opabinia, suggesting that it had lobopod walking limbs and a lateral lobe structure with attached Hurdia-like gills. The diversity of the anomalocaridids at the Burgess Shale is further increased by two additional taxa known from isolated frontal appendages. Amplectobelua stephenensis is the first occurrence of this genus outside of the Chengjiang fauna in China, but Caryosyntrips serratus is an appendage unique to the Burgess Shale. To gain a better understanding of global distribution, a possible anomalocaridid is also described from the Sirius Passet biota in North Greenland. Tamisiocaris borealis is known from a single appendage, which is similar to Anomalocaris but unsegmented, suggesting this taxon belongs to the arthropod stem-lineage, perhaps in the anomalocaridid clade. Thus, the anomalocaridids are a widely distributed and highly diverse group of large Cambrian presumed predators, which provide important information relevant to the evolution of the arthropods.
5

Evolution and taxonomy of Cambrian arthropods from Greenland and Sweden

Stein, Martin January 2008 (has links)
Arthropods have a rich fossil record spanning the Phanerozoic. Biomineralized forms such as the extinct trilobites are particularly common and are proven index fossils for biostratigraphy. Forms with an unmineralized cuticle are more rare, preserved only in so called konservat lagerstätten. Cambrian strata of Greenland have yielded rich trilobite faunas with potential for intercontinental correlation of Cambrian strata, but also an exceptionally preserved fauna, the Sirius Passet Lagerstätte. The first part of this thesis is concerned with trilobite biotratigraphy of the provisional Cambrian Series 2 in Greenland. The second part is concerned with exceptionally preserved arthropods from the Sirius Passet Lagerstätte, but also from 'Orsten' deposits from the Cambrian of Sweden. Perissopyge phenax occurs in the Henson Gletscher and Paralleldal formations spanning the Series 2 and 3 boundary interval in North Greenland. It also occurs in the Sekwi Formation of Yukon Territory, demonstrating that the species may hold potential for correlation within Laurentia. An indeterminate species of Perissopyge is shown to occur in the Ella Island Formation of North-East Greenland together with Olenellus cf. hanseni, which is similar to Olenellus cf. truemani described from the Henson Gletscher Formation. If this correlation is further corroborated it would offer a first tie-point for the An t'Sron Formation of North-West Scotland which yields Fritzolenellus lapworthi, herein reported for the first time from the Bastion Formation which underlies the Ella Island Formation. Oelandocaris oelandica from ‘Orsten’ deposits in the Cambrian series 3 and 4 boundary interval in Sweden is an early representative of the Crustacean stem lineage. Kiisortoqia avannaarsuensis is a new arthropod from the Sirius Passet Lagerstätte with robust antennulae strikingly similar to the 'raptorial' limb of the problematic anomalocaridids. The ventral morphology of the 'bivalved' Isoxys volucris is described for the first time and compared with other species assigned to Isoxys from Cambrian lagerstätten around the world. Finally, Siriocaris trolla, is a new arthropod that similarities with trilobites and certain ‘trilobitomorphs’ but seems to lack important synapomorphies of these taxa, though this may be due to preservational limitations in the material at hand.
6

The holocene history of the great Alvar of Öland

Königsson, Lars-König January 1968 (has links)
No description available.
7

A Phylogenetic Appraisal of Pachycormus bollensis: Implications for Pachycormiform Evolution

Lindkvist, Maria January 2012 (has links)
The Pachycormiformes were a successful group of stem-teleosts. Although they persisted for more than 100 million years in the Mesozoic seas and occupied a significant space of the ecosystem, little is known about this most diverse group. One of the earliest pachycormiformes is the lower Jurassic Pachycormus bollensis. A reconstruction of the phylogeny with the early P. bollensis together with more derived and earlier studied species has yielded important information about the relationships within the group. Both a parsimony analysis and a Bayesian analysis were performed. Three exceptionally complete specimens of P. bollensis from the Holzmaden-locality were used for the study. The resulting trees strongly supported pachycormiform monophyly. Three major ecomorphological clades were returned from the analyses: the filter-feeders, hyper carnivores and a more generalist predator radiation that included P. bollensis. Despite, node support within the pachycormiformes are generally weak. The tooth-structure and the phylogenetic position of P. bollensis might indicate an intermediate grade between the filter-feeders and the hyper carnivores. / Pachycormiformer var en mycket framgångsrik ordning utav stam-teleoster. Trots att de överlevde i mer än 100 miljoner år i de Mesosoiska haven och erövrat ett flertal olika platser i ekosystemet, är denna mågfacetterade grupp som helhet tämligen okänd. Pachycormus bollensis från yngre jura är en av de tidigste arterna i denna grupp. En fylogenetiskt rekonstruktion av den tidiga P. bollensis tillsammans med yngre, mer utvecklade arter kan ge viktig information om släktskapen inom gruppen. En parsimonisk analys och en Bayesian analys utfördes. Tre exceptionellt bevarade exemplar av Pachycormus bollensis från Holzmaden användes i studien. Resultatet visar på ett stark monofyletiskt sammanband inom pachycormiformerna. Båda analyserna visade robusta resultat för tre övergripande grupper; filtrerare, karnivorer och en mer generell predator linje som inkluderar P.  bollensis. Dock hade de interna släktskapen inom varje större grupp svagt stöd. Tand-stukturen tillsammans med den fylogenetiska placeringen av P. bollensis kan tyda på en intermediär grupp mellan filterarna och karnivorerna.
8

En uppdatering om människans evolution : med betoning på forskning från de senaste fem åren samt koppling till kurslitteratur för gymnasiet / An update on human evolution  : emphasizing research from the last five years with a connection to course literature for upper secondary school

Gustavsson, Emelie, Kjellgren, Sofie January 2018 (has links)
början av 2000-talet sekvenserades det första hela mänskliga genomet och sedan dess har teknikerna förfinats, effektiviserats och förbättrats, så att utvecklingen på många områden, däribland forskningen om människans evolution, går fortare än någonsin tidigare. Från att ha sekvenserat en molekyl i taget är det idag möjligt att sekvensera miljontals molekyler parallellt och dessutom till ett så lågt pris att fler nu har möjlighet att använda sig av teknikerna. Bara under de senaste fem åren har det hänt mycket på området människans evolution och det är detta som vi kommer redogöra för i den här studien. Vi redovisar nya upptäckter –såsom att Homo naledi artbestämdes 2015 –, stärker gamla hypoteser –såsom att Homo sapiens utvandrade ur Afrika –samt stryker andra hypoteser –såsom att Australopithecus afarensis skulle vara den saknade länken mellan släktet Australopithecus och släktet Homo. Mycket har skett inom forskningen på människans evolution. Tillgång till nya biologiska tekniker har tillsammans med paleontologiska upptäckter bidragit till att skapa en större samstämmighet inom båda områden. Genom att teknikerna utvecklas och kompletterar varandra kan en större konsensus i resultaten skapas. Att utvecklingen av forskningen går fort fram har konsekvenser även för kurslitteraturen i gymnasieskolan. Vi analyserar därför om gymnasielitteraturen hinner med samt om förenklingarna som görs i den är rimlig. Det är svårt att avgöra om kurslitteraturen uppdateras i tillräcklig takt då förenklingarna är så pass stora. Vi anser att flera av de jämförda böckerna är tvetydiga i sina beskrivningar och framställer fakta som säkerställd, vilket inte alltid stämmer överens med hur området ser ut i verkligheten.
9

Late Eocene through Oligocene calcareous nannofossils from the paleo-equatorial Pacific Ocean – taxonomy, preservation history, biochronology and evolution

Blaj, Teodora January 2009 (has links)
This study aims to unravel the ecological and evolutionary dynamics within the calcareous nannofossil communities at the Eocene/Oligocene (E/O) transition and during the Oligocene time when Cenozoic 'icehouse' conditions were established. The main question this study aims to answer is whether the changes in the nannofossil assemblages were controlled by intrinsic evolutionary trends or if the changes were controlled by environmental factors such as changes in temperature and nutrient availability in the surface water. These questions are addressed with detailed analyses of the taxonomy, biostratigraphy and fluctuations in abundance and diversity of calcareous nannofossil assemblages from a continuous latest Eocene through Oligocene sediment section from the ODP Site 1218 (8°53.38´N, 135°22.00´W), paleo-equatorial Pacific Ocean. An improved nannofossil taxonomy and biostratigraphy has been established. At the E/O transition, changes in the nannofossil preservation mimics changes in calcium carbonate content. A detailed investigation of late Eocene and Oligocene sediments yields age estimates for ten nannofossil bioevents. Morphometric studies of the Reticulofenestra umbilicus-R. hillae show that these cannot be subdivided into two different morphospecies. Based on different morphometry and stratigraphic ranges, the Oligocene Sphenolithus lineage appears to be the result of a combined anagenetic and cladogenetic evolution. A new nannolith species is described: Triquetrorhabdulus longus. High-resolution nannofossil data indicate changes in the composition, abundance and diversity of the mid-Oligocene assemblages. Intervals of high diversity index coincide with Oi-glaciation events. However, visual examination of the variations in abundance of nannofossil taxa do not appear to correlate with changes in either oxygen or carbon isotopes. This presumably indicates that a dynamic equilibrium did not exist between these Oligocene nannoplankton assemblages and changes in surface water temperature or productivity conditions. / Doctoral Thesis in Marine Geoscience at Stockholm University, Sweden 2009

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