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Chemical signaling and pheromone evolution in plethodontid salamandersPalmer, Catherine Anne 28 May 2004 (has links)
My dissertation focuses on the evolutionary forces that have shaped the chemical
signaling system of plethodontid salamanders. Pheromones mediate two phases of
plethodontid reproduction: mate attraction prior to courtship and female persuasion
during courtship. Substrate-borne chemical signals are believed to play an important
role in mate attraction for these animals. A behavioral assay of sex- and species-specific
odor preferences in closely related species of Plethodon indicates that: (1)
there is asymmetry on the receiver side of the system, wherein male salamanders
invest more energy searching for mating partners than do females; (2) substrate-borne
chemical signals are sexually dimorphic and male preference strongly favors the
female odor versus the male odor; (3) females of allopatric salamander species have
evolved distinctive chemical cues; and (4) female chemical signals of sympatric
species are divergent and may play a role in sexual isolation.
Sexual persuasion is another phase of plethodontid reproduction that is
mediated by chemical signals. Plethodontid Receptivity Factor (PRF) is a
proteinaceous pheromone that is produced by the male and delivered to the female
during courtship. Female receptivity increases following application of this
pheromone. PRF is a recent innovation of the male courtship signal, originating in
eastern Plethodon (~27 MYA). Codon-substitution models indicate that several amino
acid sites along the PRF protein have experienced positive selection. Structural
modeling suggests that many of these selected residues are important for receptor
binding. Adaptive change in this pheromone is likely driven via a coevolutionary
association with female receptors.
The male plethodontid courtship signal, however, is comprised of multiple
chemical components. I investigate micro- and macro-evolutionary divergence in
plethodontid chemical communication by surveying two additional pheromone
component genes, PMF and SPL. Like PRF, regions of the PMF and SPL genes have
experienced adaptive change. At least one of these components (SPL) has been
retained in the signaling system for ~100 MY. However, significant differences in the
composition of the courtship pheromone are evident in some plethodontid lineages. It
appears as if at least two lineages (Desmognathus and eastern Plethodon) use different
major pheromone components and yet achieve the same behavioral response in the
female (increased receptivity). / Graduation date: 2005
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Vickers focus and mortlach-examining cultural connections in the Makotchi-Ded Dontipi localeMokelki, Lorie Lynn 07 June 2007
Many of the pre-contact and early contact cultures of the Northern Plains have been the subjects of debate in archaeological circles. Mortlach and Vickers focus are no exception. One of the issues to date is the possible relationship between these two groups. A key to understanding this relationship lies in the Makotchi-Ded Dontipi locale in Manitobas Lauder Sandhills. This unique ecological island is home to a great number of sites (Hamilton and Nicholson1999), including neighboring Vickers focus and Mortlach sites.<p>This study offers the results of a comprehensive analysis of the pottery assemblages recovered from the Jackson, Vera, Twin Fawns, Schuddemat and Hollow B sites of the Makotchi-Ded Dontipi locale. In addition, it examines the prior cultural affiliation of these sites. Though in many ways different from eastern Vickers focus assemblages, Jackson and Vera assemblages should be considered Vickers focus. Many of the discrepancies are due to the changing nature of the sites over time in conjunction with contact with neighboring Mortlach groups. Schuddemat and Twin Fawns also differ from typical Mortlach assemblages. These differences can be attributed to their location on the eastern periphery of the Mortlach spatial distribution where they came in contact with, and were likely joined by Vickers focus people.<p>Mortlach, Vickers focus and Wascana ware are likely all a part of a larger phenomenon of eastern Woodlands migration onto the Canadian Plains. These cultures became distinct over time through interaction with neighboring groups and exploitation of territorial resource bases. Though distinct, they share a number of similarities reflecting common ancestors. These similarities culminate in the Makotchi-Ded Dontipi locale where interaction between Mortlach and Vickers focus people likely resulted in the amalgamation of Vickers focus into Mortlach. This amalgamation is reflected in the pottery assemblages of Twin Fawns and Schuddemat which seem to represent a Vickers variant of the Lake Midden subphase of Mortlach.
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General biology of woodland caribou based on collection of local and traditional knowledge in north-central SaskatchewanCarriere, Naomi Blossom 22 September 2010
Woodland caribou are listed as a threatened species in Saskatchewan. The need for contemporary data is paramount for conservation of this species. There has been a dramatic increase in the number of threats to woodland caribou: forestry and logging, road development and expansion, mineral exploration and other long term changes to the landscape. Despite previous research effort, the current distribution and critical habitat of woodland caribou in north-central Saskatchewan is still poorly understood. Drawing upon the knowledge of a selected target group, interviews have been conducted to attain local and traditional knowledge on woodland caribou. Local knowledge has been used to identify key information about woodland caribou critical habitat and ecology in the north central region and more remote areas. Through the objectives of this research we have been able to identify current and historical abundance patterns; adult and calf biology; predator prey interactions; human activity on the landscape and potential effect on woodland caribou ecology; and weather/fire patterns and the potential effect on woodland caribou distribution. The significance of this type of research is critical in understanding woodland caribou biology in northern and remote areas. In addition, this project recognizes contributions and involvement of Aboriginal peoples in academic and government research initiatives.
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General biology of woodland caribou based on collection of local and traditional knowledge in north-central SaskatchewanCarriere, Naomi Blossom 22 September 2010 (has links)
Woodland caribou are listed as a threatened species in Saskatchewan. The need for contemporary data is paramount for conservation of this species. There has been a dramatic increase in the number of threats to woodland caribou: forestry and logging, road development and expansion, mineral exploration and other long term changes to the landscape. Despite previous research effort, the current distribution and critical habitat of woodland caribou in north-central Saskatchewan is still poorly understood. Drawing upon the knowledge of a selected target group, interviews have been conducted to attain local and traditional knowledge on woodland caribou. Local knowledge has been used to identify key information about woodland caribou critical habitat and ecology in the north central region and more remote areas. Through the objectives of this research we have been able to identify current and historical abundance patterns; adult and calf biology; predator prey interactions; human activity on the landscape and potential effect on woodland caribou ecology; and weather/fire patterns and the potential effect on woodland caribou distribution. The significance of this type of research is critical in understanding woodland caribou biology in northern and remote areas. In addition, this project recognizes contributions and involvement of Aboriginal peoples in academic and government research initiatives.
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Vickers focus and mortlach-examining cultural connections in the Makotchi-Ded Dontipi localeMokelki, Lorie Lynn 07 June 2007 (has links)
Many of the pre-contact and early contact cultures of the Northern Plains have been the subjects of debate in archaeological circles. Mortlach and Vickers focus are no exception. One of the issues to date is the possible relationship between these two groups. A key to understanding this relationship lies in the Makotchi-Ded Dontipi locale in Manitobas Lauder Sandhills. This unique ecological island is home to a great number of sites (Hamilton and Nicholson1999), including neighboring Vickers focus and Mortlach sites.<p>This study offers the results of a comprehensive analysis of the pottery assemblages recovered from the Jackson, Vera, Twin Fawns, Schuddemat and Hollow B sites of the Makotchi-Ded Dontipi locale. In addition, it examines the prior cultural affiliation of these sites. Though in many ways different from eastern Vickers focus assemblages, Jackson and Vera assemblages should be considered Vickers focus. Many of the discrepancies are due to the changing nature of the sites over time in conjunction with contact with neighboring Mortlach groups. Schuddemat and Twin Fawns also differ from typical Mortlach assemblages. These differences can be attributed to their location on the eastern periphery of the Mortlach spatial distribution where they came in contact with, and were likely joined by Vickers focus people.<p>Mortlach, Vickers focus and Wascana ware are likely all a part of a larger phenomenon of eastern Woodlands migration onto the Canadian Plains. These cultures became distinct over time through interaction with neighboring groups and exploitation of territorial resource bases. Though distinct, they share a number of similarities reflecting common ancestors. These similarities culminate in the Makotchi-Ded Dontipi locale where interaction between Mortlach and Vickers focus people likely resulted in the amalgamation of Vickers focus into Mortlach. This amalgamation is reflected in the pottery assemblages of Twin Fawns and Schuddemat which seem to represent a Vickers variant of the Lake Midden subphase of Mortlach.
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Monitoring and prediction of ecological succession by measurement of functional characteristics of soilHill, Thomas C. J. January 1995 (has links)
No description available.
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Historical resource use and ecological change in semi-natural woodland : western oakwoods in Argyll, ScotlandSansum, Philip Andrew January 2004 (has links)
This thesis investigates the ecological history of western oakwoods in the Loch Awe area,Argyll, Scotland. By combining historical evidence for human use of woodland resources with palaeoecological evidence for past ecological change the influence of man on the current condition of biologically important semi-natural woods is assessed. A chronology of human activities relevant to the woodland ecology of the study area is assembled from estate papers and other documentary sources. Vegetation change during the last c. 1000 years is elucidated by pollen analysis of radioisotope dated sediments from small hollows located within three areas of western oakwood believed to be ancient. The results are related to current condition and the hypothesis that the species composition of the woods exhibited temporal stability in the recent past is tested. Mechanisms of change culminating in the modem species compositions of the woods are suggested by synthesizing independent findings from historical and palaeoecological approaches. The documentary record indicates management in the 18th and 19th centuries to supply oak bark and coppice wood for commercial purposes. In the 20th century woodland use has been relatively minor except as a grazing resource. In the period before 1700 AD the woods were used for wood for local domestic needs and to shelter livestock. The palaeoecological record indicates a lack of stability in species composition during the last millennium. Relatively diverse woods still containing natural features such as old-growth were transformed in the medieval period into disturbed open stands depleted in natural features. Declining productivity was locally alleviated by the introduction of new modes of exploitation around or prior to 1700 AD. The current condition of the woods, rather than being the direct result of an economic design, is the consequence of post-disturbance biotic processes following the abandonment of management in the late 19th century. The findings are related to the conservation of the wider western oakwood resource.
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Fine resolution pollen analysis of late Flandrian II peat at North Gill, North York moorsInnes, James B. January 1989 (has links)
Pollen and charcoal percentage and concentration analyses have been conducted upon several upland peat profiles of late Flandrian II and early Flandrian III age at North Gill, North York Moors, where earlier research had proven recurrent major pre Elm Decline woodland disturbance, supported in one profile by radiocarbon dating. Fine temporal resolution pollen analysis (FRPA) involving the use of contiguous millimetre sampling was applied to Flandrian II disturbance phases at five of the North Gill profiles. At North Gill 1A a further phase of disturbance near the end of Flandrian II was examined using FRPA to study evidence of pre Elm Decline agricultural activity, and at this profile both the horizontal and vertical resolution limits of the technique were tested by progressively finer sub-sampling. The millimetre level FRPA analyses showed that each of the examined pre Elm Decline disturbance phases was an aggregate feature, composed of a number of smaller sub-phases, the ecological effects of which in terms of spatially-precise woodland successions and community structures were assessed and contrasted. Inter-profile spatial comparison of the ecology of woodland disturbances has been made at both FRPA and conventional scales of temporal resolution. FRPA study of the late Flandrian II disturbance phase at North Gill 1A showed that cereal cultivation had occurred prior to the Elm Decline as part of a multi-phase period of agricultural land-use activity. The high resolution spatial and temporal data from North Gill have shown FRPA to be a most sensitive palaeoecological technique, and are discussed in relation to the effects of disturbance upon mire and woodland ecosystems, Mesolithic land-use, pre Elm Decline cereal cultivation and early Neolithic land-use.
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The domestic economy at locus 2 of the Allen site (33at653) a Late woodland - Late prehistoric household in southeastern Ohio /Formica, Tracy H. January 2006 (has links)
Thesis (M.S.)--Ohio University, August, 2006. / Title from PDF t.p. Includes bibliographical references.
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The origins of Abbott Zoned Incised ceramics in the late Middle Woodland Virginia coastal plain : an LA-ICP-MS analysis /Steadman, Laura Marie. January 2008 (has links)
Thesis (Honors)--College of William and Mary, 2008. / Includes bibliographical references (leave 63-73). Also available via the World Wide Web.
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