Global ETD Search

1	A taxonomic review and phylogenetic analysis of Homo habilis Chamberlain, A. T. January 1987 (has links) No description available. 301 Hominid fossil analysis
2	DNA recovery and identification from stone tool microcracks Shanks, Orin C. 28 February 2003 (has links) The studies described here introduce a model for residue preservation on stone tools. They simulate stone tool manufacture in order to define parameters important for the study of DNA residues. Microscopic examination of stone tools has identified microcracks that trap DNA and protein from animal blood cells. Thorough investigation of different methods to recover residues from stone tools shows that surface washing leaves DNA and protein, trapped in subsurface microcracks. However, other extraction techniques are able to release 60-80% of DNA and protein residues. Previous research documents the identification of protein from stone tools sonicated in 5% ammonium hydroxide, but it remains untested whether the same treatment yields useable DNA. Using this treatment, I identified 13-year-old DNA residues from experimentally manufactured stone tools. In addition, results clearly indicate that washing procedures typically used to curate stone tools removed only a small fraction of the DNA deposited during animal butchery. Twenty-four pieces of chipped stone recovered from the Bugas-Holding site were studied to explore the validity of ancient DNA residue identifications. Nine tools yielded DNA residues. Modern humans did not touch three of these tools, which suggests that the DNA recovered from them was present prior to excavation. One tool, which was handled by excavators without gloves, harbored DNA from three species, and these templates competed during PCR. On at least two tools, handling after excavation introduced animal DNA unrelated to tool use. Careful testing of Bugas-Holding chipped stone suggests that stone tools may harbor both ancient and modern DNA, and that investigators must take great care to exclude modern DNA from ancient specimens. Ultimately, I developed and streamlined a method to analyze DNA-containing residues preserved on stone tools. This led to several technical improvements in ancient DNA residue analysis. These include a more effective DNA recovery protocol, methods to measure sensitivity and inhibition of PCR in each sample, and strategies to surmount competition between templates during amplification, which can occur in samples that contain DNA from multiple species. These new developments will help future investigators achieve the full potential of ancient DNA residue analysis. / Graduation date: 2003 Archaeological chemistry DNA, Fossil -- Analysis Stone implements
3	Makrofossilanalys som ekologiskt verktyg : En metodutvärdering Pettersson, Siri January 2017 (has links) Approximately 50 percent of all endangered species in Scandinavia are associated with old agricultural landscapes. During the agricultural industrialization of the past century the traditional practices and methods that created these environments have been phased out. This has brought on a serious decline and fragmentation of biomes that many endangered species depend on. Knowledge of traditional agricultural landscapes and their species dynamics is needed to make well informed decisions regarding their care and restoration. One way to acquire such knowledge is to study fossil plant remnants from old agricultural contexts. In this study sub-fossil Cyperaceae achenes were analyzed in an attempt to identify them. The achenes had been preserved in three Iron Age wells (80-980 AD) at the Gilltuna settlement in central Sweden and were found during an archeological investigation in 2010. The purpose of this study was to identify the achenes to species level, make conclusions about the ecology of the surrounding landscape, and construct simple species identification key as well as evaluate archaeobotany as an ecological tool. The identification attempt resulted in 14 determined species, which were in consistency with previous landscape analyses made using ecological species distribution. The resulting identification key is a suggestion, to be expanded in the future. This method can undoubtedly provide further knowledge of prehistoric and historical biomes, but in order to draw useful conclusions the identification technique further as well as knowledge of present regional ecology must be developed, especially concerning different Cyperaceae species‟ response to different kinds of stress. macro fossil analysis cyperaceae sedge seed archaeobotanic paleo ecology sweden conservation makrofossilanalys arkeobotanik paleoekologi växtekologi ekologi historisk ekologi cyperaceae halvgräs makrofossil subfossil achen nöt frukt frö metodutvärdering artidentifiering identifiering järnålder vikingatid romersk järnålder Gilltuna västerås län naturvård äng ängsmark hage gräsmark Ecology Ekologi Botany Botanik Archaeology Arkeologi

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