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A dipterological perspective on the Holocene history of the North Atlantic areaSkidmore, P. January 1996 (has links)
Whilst a copious literature testifies to the value of subfossil insect analyses in the interpretation of Holocene deposits (Buckland Ind Coope, 1991; Elias, 1994), most of this results from studies of Coleopterous material . Although Dipterous fragments are often abundant in the same deposits, they have received little attention. This Thesis is concerned primarily with establishing the great value of Dipterous subfossill and the potential for advances in this field. Dipterous morphology is considered and features of primary value in the identification of subfossil material is highlighted. Problems with the traditional taxonolic criteria, insofar as identification of such material is concerned, are discussed, and new approaches are recommended. Thus, a brief survey of the morphology of Tipuloid larval head-capsules, and a revisional paper on the puparia of British Sphaeroceridlt, are included. The study includes many case-studies from excavations across the region, spanning the last 5,000 years. Although there, is an inevitable bias in favour of archaeological sites, and hence of the more synanthropic elements of the Dipterous fauna, situations un associated with human settlements are also discussed. A major objective in this work was to examine the role of Diptera in the insect colonisation of lands left in a state of tabula rasa by receding glaciations, The geographical aea concerned here comprises the entire North Atlantic continental seaboard and islands from France and Labrador northwards. This area saw the major western expansion of the Celts, Romans and the Vikings, from whose settlements much of the Dipterous material from archaeological deposits was obtained for this thesis. It also saw the eastern migration of Inuit cultures from the Canadian Arctic into Greenland. Dipterous subfossils tell us much of the living conditions and economies of these peoples.
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Bellwether of the Canaries: Anthropogenic Influence on the Land Snail Community of the Canary IslandsWall, Alexander F. January 2016 (has links)
No description available.
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Diet and the Dietary Niches of the Malagasy Subfossil Lemurs: An Analysis of Dental Microwear, Dental Proportions, and Grit AccumulationBender, Cristel 10 May 2017 (has links)
The purpose of this study is to identify the currently supported diet and dietary niches of the Malagasy subfossil and extant lemurs. The study was conducted partially in Tsinjoarivo and Antananarivo, Madagascar in the summer of 2013. Samples were analyzed and microwear determined that the dietary niches were aligned with current literature. Grit accumulation occurs more frequently in disturbed habitats and on lower canopy levels, which suggests that human manipulation of environment can impact the dental microwear of living primates.
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Dendrochronological Analysis Of Subfossil Fraxinus From The Middle And Late Holocene Period In LithuaniaVitas, Adomas 07 1900 (has links)
Dendrochronological investigations on subfossil European ash (Fraxinus excelsior L.) wood
found in two bogs of Western Lithuania are presented. Radiocarbon dating has revealed that Fraxinus grew in the Middle and Late Holocene, from approximately 4700 BC to 1500 BC. It is proposed that the growth of Fraxinus at these bogs was limited by differing hydrological regimes. Rising soil water levels induced a long decline in radial growth followed by a sharp reduction (up to 51%) in ring widths before the trees died. Until now, forest history in Lithuania was mostly based on results from palynological studies. This research demonstrates the potential of using dendrochronology to extend the distribution record of Fraxinus in the Baltic region during different periods of the Holocene.
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Functional morphology of mammalian sacra and caudal vertebrae : implications for tail loss and positional behaviors in extinct primatesRusso, Gabrielle Antoinette 25 September 2013 (has links)
All living hominoids are characterized by taillessness and adaptations to orthograde (upright) trunk posture. Accordingly, these features have importance for our understanding of ape origins, evolutionary relationships and positional behaviors. Despite extensive study of the hominoid postcranial skeleton, researchers continue to face difficulty identifying taillessness and orthogrady from fossil material. In part, difficulties persist because although the Miocene fossil record indicates that the evolution of tail loss and orthogrady was decoupled, previous research has focused primarily on how the skeletal anatomy of extinct apes resembles that of living apes, in which these traits appear in conjunction. The remarkable diversity in tail lengths and positional behaviors exhibited by other mammals presents a valuable opportunity to employ the strength of the comparative method for testing functional hypotheses. The goal of this dissertation is to identify anatomical correlates of tail length and positional behaviors from sacral and caudal vertebral morphology among primates and other mammals in three studies. The first study examines the relationship between trabecular structure in the first sacral vertebra and positional behaviors (N= 78 primates). The second study quantifies aspects of internal (N=78 primates) and external (N= 472 mammals) sacral anatomy for correlates of relative tail length. The third study evaluates the functional morphology of caudal vertebrae among nonprehensile-tailed primates and other mammals that vary in relative tail length, offering additional insight into the anatomy associated with tail loss (N=333). The relationship between trabecular structure in the proximal sacrum and positional behaviors among living primates is somewhat unclear. Some trabecular parameters in the distal sacrum appear to have a relationship with tail length. Results support the functional links between previously and newly defined metrics from the external morphology of sacra and caudal vertebrae, and relative tail length, among primates and other mammals. Identified anatomical correlates from the extant primate sample are used to reconstruct the tail lengths of extinct primates. From the sacral data, Proconsul is reconstructed as tailless, Archaeolemur likely possessed a long tail, and Palaeopropithecus, Megaladapis and Epipliopithecus had short tails. From the caudal vertebrae data, Archaeolemur is reconstructed as possessing a long tail and Palaeopropithecus is reconstructed as having a short tail. / text
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SPATIAL AND TEMPORAL FIDELITY OF SUBFOSSIL MOLLUSCAN ASSEMBLAGES IN A MODERN, SHALLOW MARINE CARBONATE SETTINGFERGUSON, CHAD ALLEN January 2003 (has links)
No description available.
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The Importance of Curation: a Case-Study of the Subfossil Lemur Collection in the Museum of Evolution, Uppsala University / Kureringens betydelse: en fallstudie av Evolutionsmuseets paleontologiska samling av subfossila lemurerLindkvist, Maria January 2016 (has links)
In times when many natural history museums experience financial cuts, it is important to show why museums matter, what they can offer, and what they mean for both the public and the scientific society. The collections are the heart of the museum and they need to be well-managed in order to attract visitors (both researchers and public). Curation of collections is an essential part of the museum operation but it may be affected by understaffing and/or lack of physical space. If collections in need of curation (especially old collections) are left unattended, they may lose their scientific value. This project was done in order to show the importance of curation and its possibility to increase the value of a collection. The aim of this project was to show that a thoroughly explored and well curated collection becomes more accessible and interesting for internal and external sources and thereby the scientific and public value increases. This was conducted as a case-study of the collection of subfossil lemurs at the Museum of Evolution, Uppsala University. The collection was catalogued, its historical background was studied, and the old collection description was reviewed. The collection catalogue produced (Appendix D) has increased the availability and scientific value as it is now easier to get an overview of the collection, the catalogue include updated anatomical and taxonomical specimen descriptions, it is possible to administer loans on collection specimens, and the catalogue data can be published in accessible databases. The historical background (Appendices A and B) has shown that the collection has connections to other Swedish museum collections in Stockholm, Gothenburg, Malmö, and Lund. It is possible to use the information in the historical background in an eventual exhibition. This has increased the public value. However, it is possible to further increase both the availability and the value of the collection and some suggestions are given. / Denna uppsats handlar om kurering, alltså om omhändertagande av samlingar som finns på museer. Det finns många olika typer av museer, t.ex. naturvetenskapliga museer, historiska museer, konstmuseer, friluftsmuseer och hembygdsmuseer. Detta arbete är främst inriktat mot naturvetenskapliga museer med paleontologiska samlingar och varför det är viktigt att de finns och varför de ska tas om hand. Vidare visas hur en samling kan bli mer lätttillgänglig och hur dess värde kan höjas genom att noggrant kureras, katalogiseras och utvärderas. Projektet utfördes som en fallstudie av den samling av subfossila lemurer som finns på Evolutiosmuseet i Uppsala. I den sammanställning som gjordes av samlingens historiska bakgrund framkom det att folkskoleläraren Bertil Ljungqvist samlat in materialet under en expedition till Madagaskar mellan åren 1926 och 1930. På denna expedition samlades även zoologisk, botaniskt och kulturella föremål in. Dessa föremål finns idag utspridda på olika museer i Uppsala, Stockholm, Göteborg, Malmö och Lund. Det historiska bakgrund som sammanställdes i detta projekt kan användas av dessa museer om materialet ska ställas ut. Alla förmål i samlingen av subfossila lemur har fått uppdaterade beskrivningar i den nyskapade katalogen. Katalogen gör det möjligt att på ett enkelt sätt få en överblick av samlingen, det är nu även möjligt att låna föremål och samlingen är ett steg närmare att publiseras i en databas. I och med detta projekt har samlingen blivit mer tillgänglig, den är lättare att använda i olika sammanhang och därmed kan även sägas att värdet av samlingen har ökat. Dock finns det stora möjligheter att ytterliggare öka både värdet och tillgängligheten.
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Multicentennial Ring-Width Chronologies of Scots Pine Along a North-South Gradient Across FinlandHelama, Samuli, Lindholm, Markus, Meriläinen, Jouko, Timonen, Mauri, Eronen, Matti January 2005 (has links)
Four regional Scots pine ring-width chronologies at the northern forest-limit, and in the northern, middle and southern boreal forest belts in Finland cover the last fourteen centuries. Tree-ring statistics and response functions were examined, and tree-ring width variation was also compared to North Atlantic Oscillation (NAO) and volcanic forcing. The tree-ring statistics show evidence of an ecogeographical gradient along a north-south transect. The three northernmost regional chronologies share a positive response to mid-summer temperature, and all four chronologies show positive and significant correlation to early-summer precipitation. Moreover, a positive and significant relationship to winter NAO was detected in three out of four regional chronologies. NAO also drives the common (inter-regional) growth variability. Years of known cool summers caused by volcanic forcing exhibit exceptionally narrow tree rings in the three northernmost regional chronologies.
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The dendroclimatology of modern and neolithic scots pine (Pinus sylvestris l.) in the peatlands of northern ScotlandMoir, Andy January 2008 (has links)
For the first time in northern Scotland, Modern tree-ring chronologies for Scots pine growing on peat are compared against those growing on mineral substrates. Mean tree-ring growth of pine on active bogs/mires is found to be limited to 0.5 to 1 mm yr-1, compared to ≥1.5 mm yr-1 on adjacent mineral sites. Almost instant change of radial growth rates in response to changes in water levels highlights the potential use of pine in reconstructions of lake levels and water tables in bog and mire. Dendroclimatological analysis identifies January and February temperatures to often be more important than summer temperature. Positive correlation of ring-width and North Atlantic Oscillation (NAO) indices also occur in January and February. Lower winter temperatures, due to increased altitude and distance from the moderating effects of the ocean, may be important in limiting tree growth near its northern margin. Moving correlation functions identify a widespread reduction in the response of pine growing on both substrates from the 1920s. Nine subfossil pine site chronologies located beyond the species current northern limit are cross-matched to form a chronology called WRATH-9. This chronology is tentatively crossdated against Irish pine chronologies to provide the first picture of Neolithic Scots pines 200 year expansion from c. 3200 BC and subsequent 250 year retreat across northern Scotland at annual resolution. The mean orientation of maximum radial growth at eleven modern pine sites is found to coincide well with the W/SW prevailing wind, suggesting Scots pine may provide a good proxy indicator of wind. Six coeval Neolithic sites indicate a broadly consistent northerly prevailing wind. This provides tentative evidence for a change of prevailing wind that may be related to a southward incursion of the polar front in the eastern N. Atlantic. The potential of this exciting subfield of dendroclimatological analysis is called dendroaeology and is highlighted for further research.
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Progress In Constructing A Long Oak Chronology From The Central United StatesStambaugh, Michael C., Guyette, Richard P. 07 1900 (has links)
We describe methods and progress in developing the American Long Oak Chronology (ALOC),
an effort to construct an oak tree-ring chronology from the Central US that spans the Holocene. Since 2000, we have collected and measured ring widths on over 550 pieces of subfossil oak (Quercus) wood. Over 330 oak samples have been radiocarbon dated, with ages ranging up to 14,000 cal yr B.P. A 1,093- year-long tree-ring record has been constructed from live and subfossil bur oaks (Q. macrocarpa Michx.) and swamp white oaks (Q. bicolor Willd.) growing along and buried in sediments of streams that flow through northern Missouri and southern Iowa, USA. Here we describe the ALOC for the period A.D. 912–2004 to demonstrate its dendrochronological value, display the material quality, and emphasize the importance of chronology construction. We also report on progress in developing older floating chronologies. The development of more long, multi-millennium chronologies will be an important contribution to dendroclimatology. These chronologies will be particularly useful to the Central US, a region with a continental climate and limited temporal depth of annually resolved paleorecords. Perhaps more critical is its location in the middle of one of the most important agricultural regions in the world.
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