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Articles 61 - 90 of 422
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Pre-Processing Techniques Applied To Automatic Taxon Identification On Fish Otoliths, Ramon Reig-Bolaño, Pere Marti-Puig
Pre-Processing Techniques Applied To Automatic Taxon Identification On Fish Otoliths, Ramon Reig-Bolaño, Pere Marti-Puig
International Congress on Environmental Modelling and Software
This paper analyzes the characteristics of a rotation-invariant Feature space to be used in a classifier of fish otoliths, it is compared to two other Feature spaces, one with raw data and another with transformed data (using the Elliptic Fourier Descriptors EFD). Otoliths are found in the inner ear of fish. Their shape can be analyzed to determine sex, age, populations and species, and thus they can provide necessary and relevant information for ecological studies. The Automatic Taxon Identifier (ATI) is used to classify fish otoliths directly from a query image and is implemented on-line in a Public Database. This …
Use Of Remote Sensing To Assess Changes In Wetland Plant Communities Over An 18-Year Period: A Case Study From The Bear River Migratory Bird Refuge, Great Salt Lake, Utah, Melina Santos Vanderlinder, Christopher M. U. Neale, David E. Rosenberg, Karin M. Kettenring
Use Of Remote Sensing To Assess Changes In Wetland Plant Communities Over An 18-Year Period: A Case Study From The Bear River Migratory Bird Refuge, Great Salt Lake, Utah, Melina Santos Vanderlinder, Christopher M. U. Neale, David E. Rosenberg, Karin M. Kettenring
Western North American Naturalist
Successfully managing wetlands requires monitoring changes in plant community composition. We used remote sensing techniques to document the replacement of desirable native wetland vegetation with invasive species in response to catastrophic flood disturbance in the 1980s and to evaluate wetland vegetation management between 1998 and 2010. We conducted our study at the Bear River Migratory Bird Refuge wetlands, which are located on the northeastern arm of the Great Salt Lake in northern Utah. We acquired high-resolution airborne multispectral imagery of the refuge in 1992 and 2010 to quantify changes in vegetation cover over time. We produced classified vegetation maps for …
Phylogeography Of The Scaled Quail In The American Southwest, Damon Williford, Randy W. Deyoung, Rodney L. Honeycutt, Leonard A. Brennan, Fidel Hernández
Phylogeography Of The Scaled Quail In The American Southwest, Damon Williford, Randy W. Deyoung, Rodney L. Honeycutt, Leonard A. Brennan, Fidel Hernández
Western North American Naturalist
We used sequences from the mitochondrial control region to examine the phylogeography and historical demography of the Scaled Quail and to determine whether the geographic distributions of mtDNA genealogy were concordant with the distribution of the subspecies. Overall, the Scaled Quail exhibited lower haplotype and nucleotide diversity than other quail species. The highest levels of haplotype diversity were found in 3 Texas counties: Dimmit, La Salle, and Hudspeth. The Scaled Quail exhibited no phylogeographic structure among its 16 haplotypes, and the patterns of genetic variation were not congruent with potential geographic barriers or current subspecies taxonomy. The geographic distribution of …
The Influence Of Breeding Experience On Nest Success In Red-Winged Blackbird, George M. Linz, Richard S. Sawin, Mark W. Lutman
The Influence Of Breeding Experience On Nest Success In Red-Winged Blackbird, George M. Linz, Richard S. Sawin, Mark W. Lutman
Western North American Naturalist
The Red-winged Blackbird (Agelaius phoeniceus) is a polygynous species, and females are typically responsible for the majority of parental care. Despite their limited involvement, males can contribute to reproduction through nest defense and the feeding of nestlings. Some aspects of nest defense may be learned, and older males are more likely to feed young, suggesting that males with previous breeding experience may enjoy higher nest success than their naïve counterparts. We manipulated territory ownership on 10 wetlands in central North Dakota in order to examine the influence of breeding experience on reproductive success. We found no evidence that …
Presence Of The Exotic Weevil (Rhinocyllus Conicus Fröelich) At High Elevations In The Rocky Mountains Of Colorado, Julia J. Hicks, Susan W. Beatty, Timothy R. Seastedt
Presence Of The Exotic Weevil (Rhinocyllus Conicus Fröelich) At High Elevations In The Rocky Mountains Of Colorado, Julia J. Hicks, Susan W. Beatty, Timothy R. Seastedt
Western North American Naturalist
We examined the presence of the exotic weevil Rhinocyllus conicus Fröelich on native thistles at high elevations in the Rocky Mountains of Colorado. We tested whether the distribution of R. conicus was related to elevation by performing 2 separate studies. First, transects along an elevation gradient were sampled in Rocky Mountain National Park and presence/absence of R. conicus was scored to infer relationships between environmental variables and weevil occurrence. Second, an experiment was conducted on Niwot Ridge to determine whether weevils were able to complete their reproductive cycle and overwinter at an elevation where they do not currently exist. Results …
Apparent Adoption Of Orphaned Cougars (Puma Concolor) In Northwestern Wyoming, Travis D. Bartnick, Marilyn Cuthill, Derek Craighead, Howard B. Quigley
Apparent Adoption Of Orphaned Cougars (Puma Concolor) In Northwestern Wyoming, Travis D. Bartnick, Marilyn Cuthill, Derek Craighead, Howard B. Quigley
Western North American Naturalist
Cougars (Puma concolor) are widely distributed throughout the western portion of North America and are generally described as solitary carnivores. Most cougar social interactions have been described as instances of parental care, intraspecific strife, or breeding. We report an apparent case of an adoption of orphaned juveniles in a wild cougar population. We used radiotelemetry and direct visual observations to document an adult female, her 3 dependent offspring, and 2 orphaned juvenile males physically interacting, sharing bed sites, and sharing kills in the late winter of 2007/2008. We consider the potential benefits and/or negative effects of these social …
A Maoli-Based Art Education: Ku'u Mau Kuamo'o 'Ōlelo, Raquel Malia Andrus
A Maoli-Based Art Education: Ku'u Mau Kuamo'o 'Ōlelo, Raquel Malia Andrus
Theses and Dissertations
Leaders in K-12 education in Hawai'i are increasingly advocating for and utilizing the culture and knowledge of the kānaka Maoli, the native people of these islands, as a context for learning in a variety of curricular disciplines and approaches (Benham & Heck, 1998; Kani'iaupuni, Ledward & Jensen, 2010; Kana'iaupuni & Malone, 2006; Kahakalau, 2004; Meyer, 2004). To expand upon this trend, this thesis uses a combination of autoethnographic and critical indigenous methodologies to present a personal narrative that looks specifically at approaching art education from a Maoli perspective. Through extensive participant/observer reflections, two place-based and culture-based art education experiences are …
Analysis Of Enhanced Resolution Ers·1 Scatterometer Imagery Over The Canadian Boreal Forest, Clarence J. Wilson Iii
Analysis Of Enhanced Resolution Ers·1 Scatterometer Imagery Over The Canadian Boreal Forest, Clarence J. Wilson Iii
Journal of Undergraduate Research
The European Remote Sensing satellite, ERS-1, carries a scatterometer radar which measures the radar backscattering coefficient (rr.) over the entire earth. The primary purpose of this measurement is to determine wind speeds and directions over the ocean. Recently, however, scientists have begun considering the use of ERS-1 backscatter measurements over land surfaces (Mougin et a!., 1995; Kennett and Li, 1989a; Kennett and Ll, 1989b). The ERS-1 scatterometer measurement data provides 50 km resolution of these surfaces and repeated coverage every 4-10 days. While this temporal repetivity is very good, the spatial resolution is extremely low and thus limits applications of …
Milnesium Lagniappe, A New Species Of Water Bear (Tardigrada, Eutardigrada, Apochela, Milnesiidae) From The Southern United States, Harry A. Meyer, Juliana G. Hinton, Maria C. Dupré
Milnesium Lagniappe, A New Species Of Water Bear (Tardigrada, Eutardigrada, Apochela, Milnesiidae) From The Southern United States, Harry A. Meyer, Juliana G. Hinton, Maria C. Dupré
Western North American Naturalist
Over 200 species of freshwater and terrestrial water bears (phylum Tardigrada) are known to occur in North America. Of these, 20 species have been recorded in Louisiana. Foliose and fruticose lichen and moss samples collected in 2011 in the city of Lake Charles and in Sam Houston Jones State Park, Calcasieu Parish, Louisiana, USA, were stored in paper envelopes and later soaked in tap water overnight. Tardigrade specimens and eggs were extracted and mounted in polyvinyl lactophenol. The samples contained a new species of tardigrade. Milnesium lagniappe sp. n. has claw formula [2-3]-[3-2] and 9 sculptured bands in the dorsal …
Explanations For An Increased Cesarean Birth Rate In Guayaquil, Ecuador, Melissa Kemp, Dr. Sheri Palmer
Explanations For An Increased Cesarean Birth Rate In Guayaquil, Ecuador, Melissa Kemp, Dr. Sheri Palmer
Journal of Undergraduate Research
Over 850,000 unnecessary C-sections are performed each year in Latin America (Belizán, Althabe, Barros, & Alexander, 1999). According to a recent annual report of the Sotomayor Maternity Hospital in Guayaquil, Ecuador, 58% of total births were cesarean (Junta de B., 2004). In comparison, the overall cesarean rate in the U.S. (which is also high according to medical recommendations) is reported to be about 27% (NCHS, 2003). Unnecessary cesarean sections have resulted in increased infection, hemorrhage, damage to abdominal and urinary tract organs, drug complications, prematurity, increased neonatal illness, and longer hospitalization (Sloan et al, 2000). These reported rates in Ecuador …
Lichen Flora Of Boulder Mountain, Aquarius Plateau, Wayne County, Utah Usa: An Altitudinal Comparison Of Lichen Communities, Steven Leavitt, Dr. Larry St. Clair
Lichen Flora Of Boulder Mountain, Aquarius Plateau, Wayne County, Utah Usa: An Altitudinal Comparison Of Lichen Communities, Steven Leavitt, Dr. Larry St. Clair
Journal of Undergraduate Research
Lichen ecology is a facet of biology that remains relatively unexplored in many parts of the United States. Lichens can play an important role as indicators of local environmental conditions, as lichen species density and community structure are significantly affected by airborne contaminants and other anthropogenic influences. Obtaining baseline ecological data for local lichen communities will make it possible to continually monitor local communities and evaluate future changes in community structure.
Watering Snakes, Samuel Hirt, Kent Hatch
Watering Snakes, Samuel Hirt, Kent Hatch
Journal of Undergraduate Research
Stable isotope research is a relatively new and innovative tool in ecology. Studies have been done with stable isotopes to determine migration patterns, diet, and evidence for nutritional stress and much more. Little has been done with stable isotopes and reptiles. We conducted a stable isotope, pilot study that will help us understand what happens with snakes in relation to temperature and oxygen and hydrogen turnover ratios in water.
Life Histories Of Brook Trout (Salvelinus Fontinalis) And Their Replacement Of Cutthroat Trout (Oncorhynchus Clarki), Amy Burgess, Dr. Dennis Shiozawa
Life Histories Of Brook Trout (Salvelinus Fontinalis) And Their Replacement Of Cutthroat Trout (Oncorhynchus Clarki), Amy Burgess, Dr. Dennis Shiozawa
Journal of Undergraduate Research
The cutthroat trout (Oncorhynchus clarki) is a member of the Salmonid family native to the western North America. Brook trout (Salvelinus fontinalis) is also a member of the salmonid family but a native to eastern North America, but has been introduced into many areas in western North America due to its popularity as a game fish. Observations of the invasion of nonnative brook trout (Salvelinus fontinalis) have often resulted in the replacement of cutthroat trout (Oncorhynchus clarki). While this is the case the underlying reasons for this replacement remain largely unknown (Peterson, 2004). Studies have been conducted looking at ecological …
Effects Of Male Size On Searching Behaviors In The Sun Dance Of Bembix, David A. Tanner, James P. Pitts
Effects Of Male Size On Searching Behaviors In The Sun Dance Of Bembix, David A. Tanner, James P. Pitts
Western North American Naturalist
Males of solitary wasp species are faced with the task of locating potential mates, a task made more difficult by inconspicuous females and a landscape seemingly devoid of landmarks. Males may employ a variety of strategies to locate females. In this study, we test for variation among males within the sun dance of Bembix. We show that males ofBembix americana spinolae Lepeletier behave differently within the sun dance and that these differences can be predicted by the size of the male. We show that large males spend more time at “rest” and require a greater number of male–male contacts …
A Survey Of Invasive Exotic Ants Found On Hawaiian Islands: Spatial Distributions And Patterns Of Association, Camie Frandsen Martin
A Survey Of Invasive Exotic Ants Found On Hawaiian Islands: Spatial Distributions And Patterns Of Association, Camie Frandsen Martin
Theses and Dissertations
An intensive sampling of all ant species encountered on 6 Hawaiian Islands: Big Island, Maui, Oahu, Kauai, Molokai, and Lanai took place between 1988 and 1996. Species presence and absence was recorded at each site. Using remote sensing, variables were added insitu and used throughout my analysis. Species accumulation curves suggest that sampling was comprehensive. There is a significant trend between island area and species richness which validates the Theory of Island Biogeography for invasive species. Islands were found to be significantly nested by area, order, and tourism. Cluster analysis shows a link between elevation, land-use and island, and species …
Preliminary Checklist Of Lichens Reported From Wyoming, Dorothy E. Tuthill
Preliminary Checklist Of Lichens Reported From Wyoming, Dorothy E. Tuthill
Monographs of the Western North American Naturalist
Although lichens are a common feature in Wyoming, there has been no attempt to compile a statewide list of species since 1900. A number of surveys have been conducted in the state, especially in Yellowstone National Park and other federally managed parks and forests, though little attention has been given to lower-elevation regions of the state. The literature search conducted for this project yielded nearly 800 species names, which number was reduced to 608 currently accepted taxa. Collection locations and references are provided for each taxon, as are global ranks (conservation status, from NatureServe.org), and a brief discussion of some …
Ecology And Population Dynamics Of Sclerocactus Mesae-Verdae (Boissev. & C. Davidson) L.D. Benson, Janet J. Coles, Karin L. Decker, Tamara S. Naumann
Ecology And Population Dynamics Of Sclerocactus Mesae-Verdae (Boissev. & C. Davidson) L.D. Benson, Janet J. Coles, Karin L. Decker, Tamara S. Naumann
Western North American Naturalist
The population dynamics of Sclerocactus mesae-verdae were documented annually in 3 plots over 20 years in southwestern Colorado. Demographic studies of this duration are rare but they are necessary to gain a more accurate estimate of population trends in long-lived desert species. Sclerocactus mesae-verdae was federally listed as threatened in 1979; this study was initiated in 1986 with the objective of determining whether Colorado populations were growing, declining, or stable. Data collected yearly around 1 May included diameter, vigor, and flower/fruit counts for 1629 stems belonging to 659 plants. We used regression analysis to estimate the mean, variance, and average …
Eco Evidence Database: A Distributed Modelling Resource For Systematic Literature Analysis In Environmental Science And Management, J. Angus Webb, Siobhan C. De Little, Kimberly A. Miller, Michael J. Stewardson
Eco Evidence Database: A Distributed Modelling Resource For Systematic Literature Analysis In Environmental Science And Management, J. Angus Webb, Siobhan C. De Little, Kimberly A. Miller, Michael J. Stewardson
International Congress on Environmental Modelling and Software
Balancing the needs of the environment with human uses of natural ecosystems relies on understanding causal relationships between environmental stressors and ecological responses. Causal relationships are difficult to demonstrate in natural environments due to environmental heterogeneity, lack of replication, and confounding influences. Published scientific literature is a currently under-used source of evidence for such analyses. We describe the Eco Evidence Database – a web database application for storing and sharing the atomized findings of research studies from the literature. This ‘evidence’ can then be used in synthesis studies to test cause-effect hypotheses. The database provides a permanent, machine-independent repository for …
Dynamics Of Genetic Structure Of Population With Age Structure During Optimal Harvest With Constant Quota, Oksana Zhdanova, Efim Frisman
Dynamics Of Genetic Structure Of Population With Age Structure During Optimal Harvest With Constant Quota, Oksana Zhdanova, Efim Frisman
International Congress on Environmental Modelling and Software
Ecological and genetic consequences of optimal equilibrium harvest with constant quota in uniform and two-aged populations have been considered in this work. It has been shown analytically that maximum of equilibrium harvest income is unreachable when both age groups are harvested simultaneously. The optimal strategy of harvest is the catch of fixed portion from single age group. In addition, optimal harvest may result not only in a change in the dynamic mode of the system, but also in a considerable change in the genetic composition of the population.
An Agent-Based Model For Assessing Effects Of A Chinese Pes Programme On Land-Use Change Along With Livelihood Dynamics, And Land Degradation And Restoration, Takafumi Miyasaka, Quang Bao Le, Toshiya Okuro, Xueyong Zhao, Roland W. Scholz, Kazuhiko Takeuchi
An Agent-Based Model For Assessing Effects Of A Chinese Pes Programme On Land-Use Change Along With Livelihood Dynamics, And Land Degradation And Restoration, Takafumi Miyasaka, Quang Bao Le, Toshiya Okuro, Xueyong Zhao, Roland W. Scholz, Kazuhiko Takeuchi
International Congress on Environmental Modelling and Software
Some Payment for Ecosystem Services (PES) programmes are designed to restore ecosystem services degraded by desertification, but evaluation of their effects are not straightforward because of complex human-environment systems (HES) in drylands. A PES system is used across China (the Sloping Land Conversion Programme, SLCP), including desertified regions. Previous research on SLCP indicated the lack of HES approaches to enable the integrated assessment of socio-ecological long-term effects of the programme. In particular, assessment was needed of: (1) multiple benefits, which cannot be positively correlated, including their cost-effectiveness, and (2) the effect of shifts in economic structure, particularly from agriculture to …
Spatial Modelling Of Potential Soil Water Retention Under Floodplain Inundation Using Remote Sensing And Gis, Yun Chen, Bing Wang, C. A. Pollino, Linda Merrin
Spatial Modelling Of Potential Soil Water Retention Under Floodplain Inundation Using Remote Sensing And Gis, Yun Chen, Bing Wang, C. A. Pollino, Linda Merrin
International Congress on Environmental Modelling and Software
Flood inundation and retention are key hydrological characteristics of floodplain wetlands. They are critical to the management of environmental flows in terms of sustaining ecosystem function, biodiversity and habitat suitability. This study developed a methodology for the estimate of potential floodwater retention under floodplain inundation from ecologically significant flood return periods by coupling remote sensing and GIS technologies with spatial hydrological modelling. The Macquarie Mashes located in the central west of New South Wales of Australia were selected as the case study area. The 1-in-10 years annual recurrence interval (ARI) was identified as one of the most important return periods …
Foliar Ozone Injury On Cutleaf Coneflower At Rocky Mountain National Park, Colorado, Robert Kohut, Colleen Flanagan, James Cheatham, Ellen Porter
Foliar Ozone Injury On Cutleaf Coneflower At Rocky Mountain National Park, Colorado, Robert Kohut, Colleen Flanagan, James Cheatham, Ellen Porter
Western North American Naturalist
Surveys for foliar ozone injury on cutleaf coneflower, spreading dogbane, and quaking aspen were conducted in Rocky Mountain National Park, Colorado, from 2006 through 2010. Foliar injury in the form of ozone stipple was found on coneflower each year. The incidence of injured plants on sites with injury ranged from 5% to 100%. The severity of injury on affected foliage was generally <4% but occurred on some leaves at a level greater than 12% in 3 years and in 1 year on 1 plant at a level >75%. No foliar ozone injury was found on spreading dogbane or quaking aspen in any year of the survey. This is the first documentation of ozone injury on vegetation in Rocky Mountain National Park. While ozone has long …
Antibody Seroprevalence To Hantaviruses In Rodents From Reserva De La Biosfera Sierra De Huatla, Morelos, Elizabeth Arellano, Iván Castro-Arellano, Gerardo Suzán, Francisco X. González-Cózatl, Ricardo Morales Jiménez
Antibody Seroprevalence To Hantaviruses In Rodents From Reserva De La Biosfera Sierra De Huatla, Morelos, Elizabeth Arellano, Iván Castro-Arellano, Gerardo Suzán, Francisco X. González-Cózatl, Ricardo Morales Jiménez
Western North American Naturalist
No abstract provided.
Obituary: Wilmer Webster Tanner, 1909–2011, Stanley L. Welsh
Obituary: Wilmer Webster Tanner, 1909–2011, Stanley L. Welsh
Western North American Naturalist
Wilmer Webster Tanner, 1909–2011
Stable Isotope Diet Reconstruction Of Feral Horses (Equus Caballas) On The Sheldon National Wildlife Refuge, Nevada, Usa, Megan Kathleen Nordquist
Stable Isotope Diet Reconstruction Of Feral Horses (Equus Caballas) On The Sheldon National Wildlife Refuge, Nevada, Usa, Megan Kathleen Nordquist
Theses and Dissertations
Feral horse management has become a subject of significant controversy in the United States. This is because of differing opinions and minimal recent empirical data on feral horses. In recent years, numbers of feral horses have increased due to governmental horse removal restrictions (specifically the Wild Horse and Burro act of 1971). With increasing numbers of feral horses on rangelands, land managers are challenged with identifying the appropriate course of action for satisfying groups with differing opinions. The purpose of this study is to characterize diet consumption through the use of stable isotope dietary analysis (δ15N and δ13C). We did …
Greater Sage-Grouse Movements And Habitat Use During Winter In Central Oregon, Jennifer R. Bruce, W. Douglas Robinson, Steven L. Petersen, Richard F. Miller
Greater Sage-Grouse Movements And Habitat Use During Winter In Central Oregon, Jennifer R. Bruce, W. Douglas Robinson, Steven L. Petersen, Richard F. Miller
Western North American Naturalist
Greater Sage-Grouse (Centrocercus urophasianus) depend on sagebrush habitat for food and cover during winter, yet few sage-grouse winter ecology studies have been conducted. During January and February 2007, we monitored 22 radio-collared sage-grouse (7 females and 15 males) in central Oregon to characterize winter habitat use and movement patterns. We estimated distances traveled between locations on a weekly basis and quantified habitat characteristics at locations used by male and female sage-grouse. The birds we collared moved extensively across the landscape, using approximately 1480 km2. Sagebrush canopy height in sites used by sage-grouse varied from 0.25 to …
Changes In Life History Within An Individual's Lifetime, Eric J. Billman
Changes In Life History Within An Individual's Lifetime, Eric J. Billman
Theses and Dissertations
A central goal of life history theory is to understand the selective factors that generate the diversity of reproductive patterns observed in nature. Within lifetime changes in reproductive investment will determine an organism's fitness; however, this area of life history theory has received less attention than comparisons among population that characterize life history traits as a single population mean. Reproductive allocation can be affected by multiple cues; the integration of these cues across an organism's lifetime generates the diversity in life history strategies observed in nature. Life history studies should examine the interacting effects of multiple cues on life history …
The Relationships Among Plant Cover, Density, Seed Rain, And Dispersal Of Bromus Tectorum In High-Elevation Populations, Andrew R. Kanarek, Rebecca Hufft Kao
The Relationships Among Plant Cover, Density, Seed Rain, And Dispersal Of Bromus Tectorum In High-Elevation Populations, Andrew R. Kanarek, Rebecca Hufft Kao
Western North American Naturalist
The invasive species Bromus tectorum L. is recognized as one of the most ecologically and economically devastating weeds in the western United States. Although B. tectorumhas been studied extensively, few studies have examined its dispersal and spread. We collected data from sites with B. tectorum in and around Rocky Mountain National Park to quantify the relationships between plant cover/density and seed rain and dispersal distance. Results suggest that there is a positive relationship between density within a patch and local seed rain and that B. tectorum exhibits relatively limited short-distance dispersal (where seeds fell in close proximity to plants …
Morphological Convergence During Pregnancy Among Predator And Nonpredator Populations Of The Livebearing Fish Brachyrhaphis Rhabdophora (Teleostei: Poeciliidae), Jeff S. Wesner, Eric J. Billman, Adam Meier, Mark C. Belk
Morphological Convergence During Pregnancy Among Predator And Nonpredator Populations Of The Livebearing Fish Brachyrhaphis Rhabdophora (Teleostei: Poeciliidae), Jeff S. Wesner, Eric J. Billman, Adam Meier, Mark C. Belk
Faculty Publications
Predation can drive morphological divergence in prey populations, although examples of divergent selection are typically limited to nonreproductive individuals. In livebearing females, shape often changes drastically during pregnancy, reducing speed and mobility and enhancing susceptibility to predation. In the present study, we document morphological divergence among populations of nonreproductive female livebearing fish (Brachyrhaphis rhabdophora) in predator and nonpredator environments. We then test the hypothesis that shape differences among nonreproductive females are maintained among reproductive females between predator and nonpredator environments. Nonreproductive females in predator environments had larger caudal regions and more fusiform bodies than females in nonpredator environments; …
Usage And Development Of Molecular Markers For Investigation Of The Population And Ecological Genetics Of Bromus Tectorum L., Keith R. Merrill
Usage And Development Of Molecular Markers For Investigation Of The Population And Ecological Genetics Of Bromus Tectorum L., Keith R. Merrill
Theses and Dissertations
This thesis includes two studies: The first examined patterns of neutral genetic diversity within Bromus tectorum L. across the IMW region, and uses patterns of microsatellite (SSR) genotype distribution to make inferences about the respective roles of adaptively significant genetic variation, adaptive phenotypic plasticity, and facultative outcrossing in the ongoing invasion and recent range expansion of B. tectorum. It has been previously demonstrated that, due to extremely low outcrossing rates, it is possible to characterize individual genotypes of this species using four SSR loci. We sampled 20 individuals from each of 96 B. tectorum populations (classified by region and …