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• 1. [Article] Community assembly of benthic invertebrates on island-like marine hard substrata

  Most of the seafloor is soft sediment, so hard substrata are isolated and island-like. In this dissertation, I explore how species distribution patterns on isolated marine hard substrata resemble terrestrial ...

  Citation × Citation Citation Abstract Copy Title: Community assembly of benthic invertebrates on island-like marine hard substrata Author: Meyer, Kirstin Year: 2016 Most of the seafloor is soft sediment, so hard substrata are isolated and island-like. In this dissertation, I explore how species distribution patterns on isolated marine hard substrata resemble terrestrial island communities, drawing on classical island biogeography theory and assembly rules, and describe how benthic invertebrate communities assemble in these island-like habitats. Higher species richness occurred on larger substrata (dropstones and shipwrecks), paralleling terrestrial island communities. However, while larger islands have greater habitat diversity and primary productivity, marine hard substrata are simpler habitats. Greater elevation in the benthic boundary layer may expose fauna to faster current, higher food supply and larval flux. Substrata located closer together had more similar communities, another pattern that resembles terrestrial islands. Dropstone fauna had a clumped distribution, indicating that larvae may disperse among substrata located close together, resulting in similar communities. In Svalbard fjords, benthic megafaunal communities were significantly different between Arctic- and Atlantic-influenced fjords. Depth and temperature had the greatest influence, with the highest diversity occurring in cold Rijpfjorden and on the north Svalbard shelf. Recruitment in Svalbard fjords was spatially and temporally variable, with lower recruitment in Rijpfjorden than in Atlantic-influenced fjords and lower recruitment at greater depth. Most of the recruits in Svalbard fjords were fast-growing, poor-competitive opportunists. On shipwrecks, communities showed two mechanisms of colonization: mobile fauna with long-dispersing planktotrophic larvae, and encrusting fauna with lecithotrophic larvae. Encrusting species reproduce asexually to cover the wreck surface, and philopatry may build up dense populations, leading to uneven communities. On terrestrial islands, non-random co-occurrence is attributed to interspecific competition, but for marine substrata, there may not be a relationship. Fauna were distributed randomly on settlement plates in Svalbard fjords, even when interspecific competition was observed. On dropstones, some morphotypes co-occurred non-randomly in the absence of overgrowth competition. Non-random co-occurrence on isolated marine hard substrata may be a result of restricted larval dispersal (for pairs co-occurring less than by chance) or epibiontism (for pairs co-occurring more often than by chance). While species distribution patterns on island-like marine hard substrata resemble terrestrial islands, the mechanisms are not necessarily the same. Title: Community assembly of benthic invertebrates on island-like marine hard substrata Author: Meyer, Kirstin Year: 2016 Most of the seafloor is soft sediment, so hard substrata are isolated and island-like. In this dissertation, I explore how species distribution patterns on isolated marine hard substrata resemble terrestrial island communities, drawing on classical island biogeography theory and assembly rules, and describe how benthic invertebrate communities assemble in these island-like habitats. Higher species richness occurred on larger substrata (dropstones and shipwrecks), paralleling terrestrial island communities. However, while larger islands have greater habitat diversity and primary productivity, marine hard substrata are simpler habitats. Greater elevation in the benthic boundary layer may expose fauna to faster current, higher food supply and larval flux. Substrata located closer together had more similar communities, another pattern that resembles terrestrial islands. Dropstone fauna had a clumped distribution, indicating that larvae may disperse among substrata located close together, resulting in similar communities. In Svalbard fjords, benthic megafaunal communities were significantly different between Arctic- and Atlantic-influenced fjords. Depth and temperature had the greatest influence, with the highest diversity occurring in cold Rijpfjorden and on the north Svalbard shelf. Recruitment in Svalbard fjords was spatially and temporally variable, with lower recruitment in Rijpfjorden than in Atlantic-influenced fjords and lower recruitment at greater depth. Most of the recruits in Svalbard fjords were fast-growing, poor-competitive opportunists. On shipwrecks, communities showed two mechanisms of colonization: mobile fauna with long-dispersing planktotrophic larvae, and encrusting fauna with lecithotrophic larvae. Encrusting species reproduce asexually to cover the wreck surface, and philopatry may build up dense populations, leading to uneven communities. On terrestrial islands, non-random co-occurrence is attributed to interspecific competition, but for marine substrata, there may not be a relationship. Fauna were distributed randomly on settlement plates in Svalbard fjords, even when interspecific competition was observed. On dropstones, some morphotypes co-occurred non-randomly in the absence of overgrowth competition. Non-random co-occurrence on isolated marine hard substrata may be a result of restricted larval dispersal (for pairs co-occurring less than by chance) or epibiontism (for pairs co-occurring more often than by chance). While species distribution patterns on island-like marine hard substrata resemble terrestrial islands, the mechanisms are not necessarily the same. Close

• 2. [Article] The Performance of Four Native Perennial Forb Species Along a Climate Gradient in Pacific Northwest Prairies

  To determine how Pacific Northwest prairies are influenced by local site factors versus. regional climate, we studied the reproduction, plant size, and density of sixteen natural populations of four perennial ...

  Citation × Citation Citation Abstract Copy Title: The Performance of Four Native Perennial Forb Species Along a Climate Gradient in Pacific Northwest Prairies Author: Hendricks, Lauren Year: 2016 To determine how Pacific Northwest prairies are influenced by local site factors versus. regional climate, we studied the reproduction, plant size, and density of sixteen natural populations of four perennial forb species native to Pacific Northwest prairies: Ranunculus austro-oreganus, Sidalcea malviflora spp. virgata, Microseris laciniata, and Eriophyllum lanatum. These populations were distributed along a 700 kilometer latitudinal gradient from southern Oregon to Whidbey Island, Washington. We found significant differences in plant size and reproduction among populations for all species, but correlations among edaphic and climate variables and plant size and reproduction were weak. Instead, density was more strongly correlated with both edaphic and climate variables, suggesting that this is a better indicator of long-term demographic processes. Although a few factors are important across species (e.g., nutrient availability and minimum temperature), response is idiosyncratic at the individual species level in Pacific Northwest prairies. Title: The Performance of Four Native Perennial Forb Species Along a Climate Gradient in Pacific Northwest Prairies Author: Hendricks, Lauren Year: 2016 To determine how Pacific Northwest prairies are influenced by local site factors versus. regional climate, we studied the reproduction, plant size, and density of sixteen natural populations of four perennial forb species native to Pacific Northwest prairies: Ranunculus austro-oreganus, Sidalcea malviflora spp. virgata, Microseris laciniata, and Eriophyllum lanatum. These populations were distributed along a 700 kilometer latitudinal gradient from southern Oregon to Whidbey Island, Washington. We found significant differences in plant size and reproduction among populations for all species, but correlations among edaphic and climate variables and plant size and reproduction were weak. Instead, density was more strongly correlated with both edaphic and climate variables, suggesting that this is a better indicator of long-term demographic processes. Although a few factors are important across species (e.g., nutrient availability and minimum temperature), response is idiosyncratic at the individual species level in Pacific Northwest prairies. Close

• 3. [Article] A Hierarchical Modeling Approach to Simulating the Geomorphic Response of River Systems to Climate Change

  Anthropogenic climate change significantly affects water resources. River flows in mountainous regions are driven by snowmelt and are therefore highly sensitive to increases in temperature resulting from ...

  Citation × Citation Citation Abstract Copy Title: A Hierarchical Modeling Approach to Simulating the Geomorphic Response of River Systems to Climate Change Author: Praskievicz, Sarah Year: 2014 Anthropogenic climate change significantly affects water resources. River flows in mountainous regions are driven by snowmelt and are therefore highly sensitive to increases in temperature resulting from climate change. Climate-driven hydrological changes are potentially significant for the fluvial geomorphology of river systems. In unchanging climatic and tectonic conditions, a river's morphology will develop in equilibrium with inputs of water and sediment, but climate change represents a potential forcing on these variables that may push the system into disequilibrium and cause significant changes in river morphology. Geomorphic factors, such as channel geometry, planform, and sediment transport, are major determinants of the value of river systems, including their suitability for threatened and endangered species and for human uses of water. This dissertation research uses a hierarchical modeling approach to investigate potential impacts of anthropogenic climate change on river morphology in the interior Pacific Northwest. The research will address the following theoretical and methodological objectives: 1) Develop downscaled climate change scenarios, based on regional climate-model output, including changes in daily minimum and maximum temperature and precipitation. 2) Estimate how climate change scenarios affect river discharge and suspended-sediment load, using a basin-scale hydrologic model. 3) Examine potential impacts of climate-driven hydrologic changes on stream power and shear stress, bedload sediment transport, and river morphology, including channel geometry and planform. The downscaling approach, based on empirically-estimated local topographic lapse rates, produces high-resolution climate grids with positive forecast skill. The hydrologic modeling results indicate that projected climate change in the study rivers will change the annual cycle of hydrology, with increased winter discharge, a decrease in the magnitude of the spring snowmelt peak, and decreased summer discharge. Geomorphic modeling results suggest that changes in reach-averaged bedload transport are highly sensitive to likely changes in the recurrence interval of the critical discharge needed to mobilize bed sediments. This dissertation research makes an original contribution to the climate-change impacts literature by linking Earth processes across a wide range of spatial scales to project changes in river systems that may be significant for management of these systems for societal and ecological benefits. This dissertation includes unpublished co-authored material. Title: A Hierarchical Modeling Approach to Simulating the Geomorphic Response of River Systems to Climate Change Author: Praskievicz, Sarah Year: 2014 Anthropogenic climate change significantly affects water resources. River flows in mountainous regions are driven by snowmelt and are therefore highly sensitive to increases in temperature resulting from climate change. Climate-driven hydrological changes are potentially significant for the fluvial geomorphology of river systems. In unchanging climatic and tectonic conditions, a river's morphology will develop in equilibrium with inputs of water and sediment, but climate change represents a potential forcing on these variables that may push the system into disequilibrium and cause significant changes in river morphology. Geomorphic factors, such as channel geometry, planform, and sediment transport, are major determinants of the value of river systems, including their suitability for threatened and endangered species and for human uses of water. This dissertation research uses a hierarchical modeling approach to investigate potential impacts of anthropogenic climate change on river morphology in the interior Pacific Northwest. The research will address the following theoretical and methodological objectives: 1) Develop downscaled climate change scenarios, based on regional climate-model output, including changes in daily minimum and maximum temperature and precipitation. 2) Estimate how climate change scenarios affect river discharge and suspended-sediment load, using a basin-scale hydrologic model. 3) Examine potential impacts of climate-driven hydrologic changes on stream power and shear stress, bedload sediment transport, and river morphology, including channel geometry and planform. The downscaling approach, based on empirically-estimated local topographic lapse rates, produces high-resolution climate grids with positive forecast skill. The hydrologic modeling results indicate that projected climate change in the study rivers will change the annual cycle of hydrology, with increased winter discharge, a decrease in the magnitude of the spring snowmelt peak, and decreased summer discharge. Geomorphic modeling results suggest that changes in reach-averaged bedload transport are highly sensitive to likely changes in the recurrence interval of the critical discharge needed to mobilize bed sediments. This dissertation research makes an original contribution to the climate-change impacts literature by linking Earth processes across a wide range of spatial scales to project changes in river systems that may be significant for management of these systems for societal and ecological benefits. This dissertation includes unpublished co-authored material. Close

• 4. [Article] The Taphonomy of Archaeological Fish Remains: Experimental Approaches to Understanding the Effects of Natural and Cultural Processes on the Presence and Identification of Cut Marks

  Despite the fact that fish are a common component of coastal and other aquatic archaeological sites, fish bone taphonomy--including bone surface modifications and the effects of burial--remains woefully ...

  Citation × Citation Citation Abstract Copy Title: The Taphonomy of Archaeological Fish Remains: Experimental Approaches to Understanding the Effects of Natural and Cultural Processes on the Presence and Identification of Cut Marks Author: Willis, Lauren Year: 2014 Despite the fact that fish are a common component of coastal and other aquatic archaeological sites, fish bone taphonomy--including bone surface modifications and the effects of burial--remains woefully understudied. Various ethnographic accounts describe fish butchering techniques for immediate consumption and drying, yet cut marks are rarely reported on archaeological fish remains. To address a significant gap in our understanding of fish taphonomy, I devised an experimental research program aimed at assessing whether butchering fish produces cut marks on fish bones and, if so, what factors might account for the discrepancy between the experimental results and the archaeological record. Chapter I provides an introduction to experimental archaeology, including the criticisms and benefits of this approach. Chapter II presents the results of my initial butchery experiment, which establishes that butchering fish can produce abundant cut marks. Chapter III evaluates the effect of the butcher's skill level on the number and distribution of cut marks produced on fish bone during butchery. The results indicate that professional butchers produce nearly 50 percent fewer cut marks than novice- and intermediate-level butchers. Chapter IV addresses the effect of post-depositional taphonomic processes on the long-term visibility of cut marks. Despite a relatively short burial period (27 months), visible cut marks decreased by up to 75 percent, depending on the species. Chapter V is a re-analysis of the fish bone from column E6 at Daisy Cave (CA-SMI-261). Appling the referential framework I acquired through the experiments, I identified 62 cut marks on bones dating from the Early to Late Holocene. A comprehensive understanding of aquatic resource use has implications for a broad range of archaeological topics, including our understanding of hominid diet and resource use; identifying butchery and processing practices among fishing peoples; distinguishing between human and natural agency in the accumulation of fish remains; and assessing questions of behavioral modernity and social complexity. As we continue to recognize the primacy of coastal adaptations throughout human history, it is increasingly critical to expand the breadth of our knowledge regarding the taphonomy of fish remains at archaeological sites. This dissertation includes previously published and unpublished co-authored material. Title: The Taphonomy of Archaeological Fish Remains: Experimental Approaches to Understanding the Effects of Natural and Cultural Processes on the Presence and Identification of Cut Marks Author: Willis, Lauren Year: 2014 Despite the fact that fish are a common component of coastal and other aquatic archaeological sites, fish bone taphonomy--including bone surface modifications and the effects of burial--remains woefully understudied. Various ethnographic accounts describe fish butchering techniques for immediate consumption and drying, yet cut marks are rarely reported on archaeological fish remains. To address a significant gap in our understanding of fish taphonomy, I devised an experimental research program aimed at assessing whether butchering fish produces cut marks on fish bones and, if so, what factors might account for the discrepancy between the experimental results and the archaeological record. Chapter I provides an introduction to experimental archaeology, including the criticisms and benefits of this approach. Chapter II presents the results of my initial butchery experiment, which establishes that butchering fish can produce abundant cut marks. Chapter III evaluates the effect of the butcher's skill level on the number and distribution of cut marks produced on fish bone during butchery. The results indicate that professional butchers produce nearly 50 percent fewer cut marks than novice- and intermediate-level butchers. Chapter IV addresses the effect of post-depositional taphonomic processes on the long-term visibility of cut marks. Despite a relatively short burial period (27 months), visible cut marks decreased by up to 75 percent, depending on the species. Chapter V is a re-analysis of the fish bone from column E6 at Daisy Cave (CA-SMI-261). Appling the referential framework I acquired through the experiments, I identified 62 cut marks on bones dating from the Early to Late Holocene. A comprehensive understanding of aquatic resource use has implications for a broad range of archaeological topics, including our understanding of hominid diet and resource use; identifying butchery and processing practices among fishing peoples; distinguishing between human and natural agency in the accumulation of fish remains; and assessing questions of behavioral modernity and social complexity. As we continue to recognize the primacy of coastal adaptations throughout human history, it is increasingly critical to expand the breadth of our knowledge regarding the taphonomy of fish remains at archaeological sites. This dissertation includes previously published and unpublished co-authored material. Close

• 5. [Article] The Oligocene Fossil Caudates of Oregon: Classification, Analysis, and Insights on the Paleoecology and Conservation Biology of Pacific Newts

  Newts, abundant worldwide, have unclear pre-Pliocene evolution and phylogenetic relationships. North America has a sporadic pre-Pliocene newt record. Several undescribed fossils can address this lack ...

  Citation × Citation Citation Abstract Copy Title: The Oligocene Fossil Caudates of Oregon: Classification, Analysis, and Insights on the Paleoecology and Conservation Biology of Pacific Newts Author: Jacisin, John Year: 2014 Newts, abundant worldwide, have unclear pre-Pliocene evolution and phylogenetic relationships. North America has a sporadic pre-Pliocene newt record. Several undescribed fossils can address this lack of information. I built a character matrix of >70 morphological characters for extant newts and two fossil species, Taricha oligocenica and Taricha lindoei. Phylogenetic analyses were used to investigate the relationships of the fossil taxa within newts. The morphology of the fossil taxa was compared with extant North American newts to redescribe the fossil specimens. The past ecology and biogeography of North American fossil newts was compared with their current ecologies and distribution to better understand their evolution and dispersal and to predict possible changes for newts in the face of environmental change. Results indicate that T. oligocenica and T. lindoei are closely-related species nested within Taricha, but their relationships with extant species are unresolved; the genus itself is rooted at least 32 Ma. Title: The Oligocene Fossil Caudates of Oregon: Classification, Analysis, and Insights on the Paleoecology and Conservation Biology of Pacific Newts Author: Jacisin, John Year: 2014 Newts, abundant worldwide, have unclear pre-Pliocene evolution and phylogenetic relationships. North America has a sporadic pre-Pliocene newt record. Several undescribed fossils can address this lack of information. I built a character matrix of >70 morphological characters for extant newts and two fossil species, Taricha oligocenica and Taricha lindoei. Phylogenetic analyses were used to investigate the relationships of the fossil taxa within newts. The morphology of the fossil taxa was compared with extant North American newts to redescribe the fossil specimens. The past ecology and biogeography of North American fossil newts was compared with their current ecologies and distribution to better understand their evolution and dispersal and to predict possible changes for newts in the face of environmental change. Results indicate that T. oligocenica and T. lindoei are closely-related species nested within Taricha, but their relationships with extant species are unresolved; the genus itself is rooted at least 32 Ma. Close

• 6. [Article] Investigating an adaptive explanation for nonprogressor immune responses to SIV

  62 pages. A thesis presented to the Department of Anthropology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring ...

  Citation × Citation Citation Abstract Copy Title: Investigating an adaptive explanation for nonprogressor immune responses to SIV Author: McVeety, Kelsie Year: 2015 62 pages. A thesis presented to the Department of Anthropology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2015. Title: Investigating an adaptive explanation for nonprogressor immune responses to SIV Author: McVeety, Kelsie Year: 2015 62 pages. A thesis presented to the Department of Anthropology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2015. Close

• 7. [Article] Incompatibility and Speciation Within and Between Species

  60 pages. A thesis presented to the Department of Biology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2...

  Citation × Citation Citation Abstract Copy Title: Incompatibility and Speciation Within and Between Species Author: Moore, Hanna Year: 2015 60 pages. A thesis presented to the Department of Biology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2015. Title: Incompatibility and Speciation Within and Between Species Author: Moore, Hanna Year: 2015 60 pages. A thesis presented to the Department of Biology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2015. Close

• 8. [Article] THE SCIURIDAE (RODENTIA: MAMMALIA) OF CAVE BASIN (OREGON), A NEW MIDDLE MIOCENE MICROFOSSIL LOCALITY

  69 pages. A thesis presented to the Department of Geological Sciences and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, ...

  Citation × Citation Citation Abstract Copy Title: THE SCIURIDAE (RODENTIA: MAMMALIA) OF CAVE BASIN (OREGON), A NEW MIDDLE MIOCENE MICROFOSSIL LOCALITY Author: Biedron, Eva Marie Year: 2016 69 pages. A thesis presented to the Department of Geological Sciences and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2016. Title: THE SCIURIDAE (RODENTIA: MAMMALIA) OF CAVE BASIN (OREGON), A NEW MIDDLE MIOCENE MICROFOSSIL LOCALITY Author: Biedron, Eva Marie Year: 2016 69 pages. A thesis presented to the Department of Geological Sciences and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2016. Close

• 9. [Article] THE ROLE OF CHROMODOMAIN PROTEIN 1 (CDP-1) AT NEUROSPORA CRASSA HETEROCHROMATIN

  36 pages. A thesis presented to the Department of Biology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2...

  Citation × Citation Citation Abstract Copy Title: THE ROLE OF CHROMODOMAIN PROTEIN 1 (CDP-1) AT NEUROSPORA CRASSA HETEROCHROMATIN Author: Kim, Carissa Year: 2016 36 pages. A thesis presented to the Department of Biology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2016. Title: THE ROLE OF CHROMODOMAIN PROTEIN 1 (CDP-1) AT NEUROSPORA CRASSA HETEROCHROMATIN Author: Kim, Carissa Year: 2016 36 pages. A thesis presented to the Department of Biology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2016. Close

• 10. [Article] THE OLIGOCENE MARINE MOLLUSCAN FAUNA OF THE EUGENE FORMATION IN OREGON

  124 pages

  Citation × Citation Citation Abstract Copy Title: THE OLIGOCENE MARINE MOLLUSCAN FAUNA OF THE EUGENE FORMATION IN OREGON Author: STENTZ HICKMAN, CAROLE JEAN Year: 2016, 1969 124 pages Title: THE OLIGOCENE MARINE MOLLUSCAN FAUNA OF THE EUGENE FORMATION IN OREGON Author: STENTZ HICKMAN, CAROLE JEAN Year: 2016, 1969 124 pages Close