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Differential Mortality Drives Life-History Evolution And Population Dynamics In The Fish Brachyrhaphis Rhabdophora, Jerald B. Johnson, J. Jaime Zuniga-Vega Aug 2009

Differential Mortality Drives Life-History Evolution And Population Dynamics In The Fish Brachyrhaphis Rhabdophora, Jerald B. Johnson, J. Jaime Zuniga-Vega

Faculty Publications

Life-history theory predicts that populations experiencing different levels of extrinsic mortality will evolve divergent reproductive strategies. Previous work in the live bearing fish Brachyrhaphis rhabdophora shows that individuals from populations that occur with piscivorous fish mature earlier and at smaller sizes and have more and smaller offspring than fish from populations without predators. However, until now, there have been no data to demonstrate that differences in mortality rates actually exist between predator and predator free sites. Here we present the results of a serial mark-recapture field study designed to estimate mortality rates in natural populations of B. rhabodophora from Costa …

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Cis-Regulatory Sequence And Co-Regulatory Transcription Factor Functions In Erα-Mediated Transcriptional Repression, Richard Leroy Smith Jul 2009

Cis-Regulatory Sequence And Co-Regulatory Transcription Factor Functions In Erα-Mediated Transcriptional Repression, Richard Leroy Smith

Theses and Dissertations

Estrogens exert numerous actions throughout the human body, targeting healthy tissue while also enhancing the proliferative capacity of breast cancers. Estrogen signaling is mediated by the estrogen receptor (ER), which binds DNA and ultimately affects the expression of adjacent genes. Current understanding of ER-mediated transcriptional regulation is mostly limited to genes whose transcript levels increase following estrogen exposure, though recent studies demonstrate that direct down-regulation of estrogen-responsive genes is also a significant feature of ER action. We hypothesized that differences in cis-regulatory DNA was a factor in determining target gene expression and performed computational and experimental studies to test this …

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A Top-Down Proteomic Approach For The Discovery Of Novel Serum Biomarkers Of Pregnancy-Related Disease, Karen Merrell Jul 2009

A Top-Down Proteomic Approach For The Discovery Of Novel Serum Biomarkers Of Pregnancy-Related Disease, Karen Merrell

Theses and Dissertations

The serum fraction of blood is an ideal material in which to search for novel biomarkers for disease. It is easily obtained through relatively non-invasive means, routinely collected, and a rich treasure-trove of information about the health of an individual. Cells react to signal molecules, take up nutrients, and release waste products, fragments that are the result of proteolysis, and other molecules out into the bloodstream. If these components are unique to the cells in question, that part of the complex mixture that is the blood stream can potentially characterize the health of the tissue or organ those cells are …

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Extreme Ultraviolet Polarimetry With Laser-Generated High-Order Harmonics: Characterization Of Uranium, Nicole Brimhall Jul 2009

Extreme Ultraviolet Polarimetry With Laser-Generated High-Order Harmonics: Characterization Of Uranium, Nicole Brimhall

Theses and Dissertations

We developed an extreme ultraviolet (EUV) polarimeter, which employs laser-generated high-order harmonics as the light source. This relatively high-flux, directional EUV source has available wavelengths between 10 nm and 47 nm with easily rotatable linear polarization. The polarimeter has allowed us to characterize the optical constants of materials that may be useful for EUV optics. The instrument has a versatile positioning system and a spectral resolution of about 180, and we have demonstrated that reflectance as low as 0.1% can be measured repeatably at EUV wavelengths. We investigate the high harmonic source used for polarimetry measurements by documenting the spatial …

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The Trouble With Transfer, Kathryn Jane Groneman Jul 2009

The Trouble With Transfer, Kathryn Jane Groneman

Theses and Dissertations

It is hoped that the scientific reasoning skills taught in our biology courses will carry over to be applied in novel settings: to new concepts, future courses, other disciplines, and non-academic pursuits. This is the educational concept of transfer. Efforts over many years in the Cell Biology course at BYU to design effective assessment questions that measure competence in both deep understanding of conceptual principles and the ability to draw valid conclusions from experimental data have had at least one disquieting result. The transfer performance of many otherwise capable students is not very satisfactory. In order to explain this unsatisfactory …

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Physiological Assessment Of Chenopodium Quinoa To Salt Stress, Arturo Jason Morales Jul 2009

Physiological Assessment Of Chenopodium Quinoa To Salt Stress, Arturo Jason Morales

Theses and Dissertations

The physiological responses to salt stress were measured in Chenopodium quinoa. In a greenhouse experiment, salt water was applied to the quinoa varieties, Chipaya and KU-2, and to the model halophyte Thellungiella halophila to assess their relative responses to salt stress. Height and weight data from a seven-week time course demonstrated that both cultivars exhibited greater tolerance to salt than T. halophila. In a growth chamber experiment, three quinoa cultivars, Chipaya, Ollague, and CICA 17 were hydroponically grown and physiological responses were measured with four salt treatments. Tissues collected from the growth chamber treatments were used to obtain …

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Ethnographic Literary Journalism, Christel Lane Swasey Jul 2009

Ethnographic Literary Journalism, Christel Lane Swasey

Theses and Dissertations

Leon Dash and Ted Conover have modeled an ethnographic approach to literary journalism. This approach combines literary journalism's compelling narrative techniques with ethnographic “naturalist-like” (Brewer, 2000) thoroughness and trustworthiness. Rosa Lee: A Mother in Urban America, by Leon Dash, and Newjack: Guarding Sing Sing, by Ted Conover, exemplify this painstaking method that skillfully uses the narrative craft, generates trustworthy data, and contributes to an academic body of knowledge as well as exposing findings to the general public. Dash, Conover, and others have demonstrated the synergy and problem-solving potential of merging anthropology with literary journalism, yet there is no …

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High-Stakes Testing Under The No Child Left Behind Act: How Has It Impacted School Culture?, Rashel Anderson Tingey Jul 2009

High-Stakes Testing Under The No Child Left Behind Act: How Has It Impacted School Culture?, Rashel Anderson Tingey

Theses and Dissertations

The purpose of this study was to investigate the impact of high-stakes testing under the No Child Left Behind (NCLB) Act on school culture. Individual interviews and focus groups were conducted with first grade through sixth grade teachers and principals from two of Nebo School District's schools located in Utah. Their responses were categorized into twelve themes. Most of the teachers and principals reported that high-stakes testing negatively impacted student and teacher motivation, teaching and learning, and curriculum. They also discussed negative effects of the application questioned the accuracy of high-stakes testing. Fewer teachers and principals communicated positive effects of …

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The Hurtful Relationship: A Longitudinal Study Of Relational Aggression And Physical Health In Marriage, Matthew P. Martin Jul 2009

The Hurtful Relationship: A Longitudinal Study Of Relational Aggression And Physical Health In Marriage, Matthew P. Martin

Theses and Dissertations

Previous literature has examined the link between overt marital conflict and physical health and found that negative interactions in marriage may lead to poorer health. Moreover, recent studies have identified relational aggression as a type of covert marital conflict. However, none have tested for effects of relational aggression on physical health in marriage. The purpose of this research is to further study this type of conflict by examining longitudinal dyadic data to determine how subtle, indirect marital conflict like relational aggression affects the health of spouses. Data from 316 couples, from the first two waves of the BYU Flourishing Families …

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Autonomy-Dependency Paradox In Organization-Public Relationships: A Case Study Analysis Of A University Art Museum, Christopher E. Wilson Jul 2009

Autonomy-Dependency Paradox In Organization-Public Relationships: A Case Study Analysis Of A University Art Museum, Christopher E. Wilson

Theses and Dissertations

This study presents an exploration of the autonomy-dependence paradox inherent in organization-public relationships that is informed by paradox theory, structuration theory and scholarly and philosophical literature on authenticity. These theories suggest that relationships between organizations and their publics are defined by interdependence, or the centripetal and centrifugal forces of autonomy and dependence that cause tensions that can influence the decision making of the relational partners. They also suggest that organizations must use their agency, their knowledge of relational structures, and their understanding of their authentic selves to manage their own behavior and communication rather than that of their publics. The …

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Portrayal Of Older People In Disney Live Action Films From The 1990s And 2000s, Jennifer Gail Martin Jul 2009

Portrayal Of Older People In Disney Live Action Films From The 1990s And 2000s, Jennifer Gail Martin

Theses and Dissertations

Children as young as three years old are scared of the idea of growing old, and negative stereotypes about older people have started to develop by the time children enter elementary school. Negative stereotyping of older characters has been found to be prevalent in all forms of media. Because children use media to figure out who they are and what the world is like, this study looks at some of the most popular films of the past two decades aimed toward children. This study is a content analysis of older major and minor characters from the 60 top grossing Disney …

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Bats Along The Republican River And Its Tributaries In Southwestern Nebraska: Distribution, Abundance, And Reproduction, Matthew R. Serbousek, Keith Geluso Jul 2009

Bats Along The Republican River And Its Tributaries In Southwestern Nebraska: Distribution, Abundance, And Reproduction, Matthew R. Serbousek, Keith Geluso

Western North American Naturalist

Thirteen species of bats occur in Nebraska, but limited information is available on those inhabiting southwestern parts of the state. We investigated the distribution, abundance, and reproductive activity of bats in 5 counties in extreme southwestern Nebraska (Chase, Hays, Dundy, Hitchcock, and Red Willow). From April 2007 to April 2008, we deployed mist nets on 15 occasions at 8 localities over the Republican River and its tributaries. We captured 100 individuals representing 5 species, including the evening bat (Nycticeius humeralis), eastern red bat (Lasiurus borealis), hoary bat (Lasiurus cinereus), big brown bat (Eptesicus …

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Phytogeography And Floristics Of Pinyon-Juniper Woodlands In Northern Arizona, Kyle Christie Jul 2009

Phytogeography And Floristics Of Pinyon-Juniper Woodlands In Northern Arizona, Kyle Christie

Western North American Naturalist

This study assesses the floristic diversity and affinities of pinyon-juniper (PJ) woodlands in northern Arizona at 2 different scales: regionally within the context of North American floristic patterns and locally within the 2500-m elevation gradient of the San Francisco Volcanic Field (SFVF). An analysis based upon 245 North American floras indicates that the PJ woodlands of the SFVF share strong affinities with the adjacent Colorado Plateau and Apachian floristic elements but also show high floristic similarity to the Great Plains. Data suggest that mid-elevation woodlands of the Colorado Plateau share floristic affinities with the Great Plains that are as strong …

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Predator-Specific Mortality Of Pronghorn On Yellowstone's Northern Range, Kerey K. Barnowe-Meyer, P. J. White, Troy L. Davis, John A. Byers Jul 2009

Predator-Specific Mortality Of Pronghorn On Yellowstone's Northern Range, Kerey K. Barnowe-Meyer, P. J. White, Troy L. Davis, John A. Byers

Western North American Naturalist

Yellowstone National Park supports a small population (<300) of pronghorn (Antilocapra americana). Some individuals migrate during summer to areas characterized by reduced visibility, mixed habitat types, and a diverse predator community. Across areas selected by migratory and nonmigratory pronghorn, we documented cause-specific mortality of adults and fawns and assessed relative risk of predation by various predators. Coyotes (Canis latrans) accounted for 56% of adult predation and up to 79% of fawn predation. Cougars (Puma concolor) and wolves (Canis lupus) accounted for additional predation of adults, while cougars, black bears (Ursus americanus), and Golden …

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Postfire Recovery Of Two Shrubs In The Interiors Of Large Burns In The Intermountain West, Usa, Lori L. Ziegenhagen, Richard F. Miller Jul 2009

Postfire Recovery Of Two Shrubs In The Interiors Of Large Burns In The Intermountain West, Usa, Lori L. Ziegenhagen, Richard F. Miller

Western North American Naturalist

Shrub canopy cover can take between 10 and >50 years to recover to predisturbance levels following fire in sagebrush communities. The high degree of unpredictability of shrub recovery following prescribed fires and wildfires makes it difficult to prioritize restoration efforts and develop long-term plans for restoring or maintaining the integrity of sagebrush communities. Our overall goal was to develop a hypothesis based on descriptive data that describes the temporal pattern of recruitment for 2 important shrubs, Artemisia tridentata Nutt. ssp. vaseyana (Rydb.) Beetle and Purshia tridentata (Pursh) DC., in the interiors of large burns where little seed input from surviving …

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Genetics Of Allopatric Populations Of The Montane Vole (Microtus Montanus) And Mogollon Vole (Microtus Mogollonensis) In The American Southwest, Jennifer K. Frey Jul 2009

Genetics Of Allopatric Populations Of The Montane Vole (Microtus Montanus) And Mogollon Vole (Microtus Mogollonensis) In The American Southwest, Jennifer K. Frey

Western North American Naturalist

Variation at 21 allozyme loci and 10 restriction enzymes within the mitochondrial DNA control region was assessed among 3 allopatric populations of montane vole (Microtus montanus) in the American Southwest. Among populations of M. montanus, the population from the White Mountains, Arizona, was most genetically divergent. Genetic and biogeographic evidence supported recognition of the White Mountains population as a distinct subspecies, M. m. arizonensis. Results also supported recognition of the Mogollon vole (Microtus mogollonensis) as distinct from the Mexican vole (Microtus mexicanus).

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Range Expansion Of The Collared Peccary In New Mexico: Potential For Interactions Between Historically Separate Subspecies, Louis J. Lamit, Marguerite N. Hendrie Jul 2009

Range Expansion Of The Collared Peccary In New Mexico: Potential For Interactions Between Historically Separate Subspecies, Louis J. Lamit, Marguerite N. Hendrie

Western North American Naturalist

The collared peccary (Tayassu tajacu) is undergoing range expansion in the southwestern United States. Here we report sightings of the collared peccary from locations outside the known ranges of either of the subspecies, T. t. sonoriensis and T. t. angulatus, in south central New Mexico. Sightings include multiple individuals of different ages. This indicates that the collared peccary is expanding into previously unoccupied areas between the documented ranges of the 2 subspecies. We suggest that the possibility of gene flow between the 2 historically separate subspecies may have important evolutionary consequences.

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Captures Of Crawford's Gray Shrews (Notiosorex Crawfordi) Along The Rio Grande In Central New Mexico, Alice Chung-Maccoubrey, Heather L. Bateman, Deborah M. Finch Jul 2009

Captures Of Crawford's Gray Shrews (Notiosorex Crawfordi) Along The Rio Grande In Central New Mexico, Alice Chung-Maccoubrey, Heather L. Bateman, Deborah M. Finch

Western North American Naturalist

We captured >2000 Crawford's gray shrews (Notiosorex crawfordi) in a riparian forest mainly consisting of cottonwoods (Populus deltoides) along the Rio Grande in central New Mexico. Little has been published about abundance and habitat of Crawford's gray shrew throughout its distributional range. During 7 summers, we captured shrews in pitfall traps at 13 study sites in Bernalillo, Valencia, and Socorro counties. Capture rates of shrews were greatest in August and September, and we did not detect a response of shrews to restoration treatments that removed nonnative plants from riparian forests. Results from our study indicate that …

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Note On Mortality Of The Emerging Stonefly Pteronarcys Californica On The Jocko River, Montana, Usa, Isaac P. Rockwell, Robert L. Newell Jul 2009

Note On Mortality Of The Emerging Stonefly Pteronarcys Californica On The Jocko River, Montana, Usa, Isaac P. Rockwell, Robert L. Newell

Western North American Naturalist

Cold air temperatures may have killed several emerging nymphs and adult Pteronarcys californica on the Jocko River, Montana. Some aquatic insect taxa emerge early on the Jocko River, likely due to warm water temperatures in winter and spring. At this location, P. californica emerges approximately 5–7 weeks earlier than it does on many other streams or rivers across the United States. We hypothesize that this earlier emergence may be a mortality factor when cold fronts cause air temperatures to drop below freezing. Other mortality factors are also discussed.

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Capture Locations Of Two Endangered Rodents During A 1902 Exploration Of The Sacramento Mountains, New Mexico, Jennifer K. Frey, Robert D. Fisher, Suzanne C. Peurach Jul 2009

Capture Locations Of Two Endangered Rodents During A 1902 Exploration Of The Sacramento Mountains, New Mexico, Jennifer K. Frey, Robert D. Fisher, Suzanne C. Peurach

Western North American Naturalist

We investigated localities from which Eutamias atristriatus Bailey, 1913 (= Tamias minimus atristriatus) and Zapus luteus Miller, 1911 (= Zapus hudsonius luteus) were collected during a 1902 survey in the Sacramento Mountains, New Mexico, by the United States Biological Survey. The locality from which the holotype of Eutamias atristriatus was collected is restricted to James Canyon rather than the Rio Peñasco. Locality records indicate that the historical distribution of Zapus hudsonius luteus and its obligate wetland habitat were broader than currently realized.

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Camel Spider (Solifugae) Use Of Prairie Dog Colonies, B. D. Duval, W. G. Whitford Jul 2009

Camel Spider (Solifugae) Use Of Prairie Dog Colonies, B. D. Duval, W. G. Whitford

Western North American Naturalist

Solifugids (camel spiders) are widespread throughout arid regions of western North America and are thought to be important in structuring desert arthropod communities. Despite the ubiquity of camel spiders, little is known about their ecology. Black-tailed prairie dogs (Cynomys ludovicianus) are also widespread in western North America and are important ecosystem engineers, but they have been reduced in extent because of human activity. Here we report significantly greater numbers of camel spiders on black-tailed prairie dog colonies in southern New Mexico. The difference in vegetation structure created by prairie dog activity is likely the reason for the increased …

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Stalking The Big Bird: A Tale Of Turkeys, Biologists, And Bureaucrats By Harley Shaw, Jared B. Lee, Jerald B. Johnson Jul 2009

Stalking The Big Bird: A Tale Of Turkeys, Biologists, And Bureaucrats By Harley Shaw, Jared B. Lee, Jerald B. Johnson

Western North American Naturalist

No abstract provided.

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Ecology And Management Of The North American Moose By Albert W. Franzmann And Charles C. Schwartz, Charles J. Randel Iii Jul 2009

Ecology And Management Of The North American Moose By Albert W. Franzmann And Charles C. Schwartz, Charles J. Randel Iii

Western North American Naturalist

No abstract provided.

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Front Matter, Vol. 69 No. 2 Jul 2009

Front Matter, Vol. 69 No. 2

Western North American Naturalist

No abstract provided.

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American Pikas Inhabit Low-Elevation Sites Outside The Species' Previously Described Bioclimatic Envelope, William G. Simpson Jul 2009

American Pikas Inhabit Low-Elevation Sites Outside The Species' Previously Described Bioclimatic Envelope, William G. Simpson

Western North American Naturalist

It has been suggested that Nearctic pikas (Ochotona spp.) are good biogeographic indicators of regions containing rocky, mesic, and cool habitat characterized by long winters and short summers. I examined whether populations of pikas inhabiting distinct low-elevation locales (121–255 m) are faithfully restricted to long-winter and short-summer conditions by monitoring the climate associated with American pikas (Ochotona princeps) in the southern part of the Columbia River Gorge, Oregon. Ambient air temperatures and weather conditions in the vicinity of 4 pika-occupied rockslides were monitored with remote temperature loggers and weather stations from June 2000 to June 2001. Temperatures …

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First Documentation Of Salmincola Californiensis In Lake Tahoe, Ca–Nv, Usa, Marcy Kamerath, B. C. Allen, S. Chandra Jul 2009

First Documentation Of Salmincola Californiensis In Lake Tahoe, Ca–Nv, Usa, Marcy Kamerath, B. C. Allen, S. Chandra

Western North American Naturalist

Salmincola californiensis is a parasitic copepod in the Lernaeopodidae family that commonly parasitizes salmonid fishes (Oncorhynchus spp.) by attaching near the fins and on gill filaments. Historically their distribution was limited to streams that emptied into the Pacific Ocean. During the summer of 2006, several rainbow trout (Oncorhynchus mykiss) captured in Lake Tahoe were infested with S. californiensis. This is the first known record of S. californiensis in Lake Tahoe.

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Ant Assemblages In Intact Big Sagebrush And Converted Cheatgrass-Dominated Habitats In Tooele County, Utah, Steven M. Ostoja, Eugene W. Schupp, Kelly Sivy Jul 2009

Ant Assemblages In Intact Big Sagebrush And Converted Cheatgrass-Dominated Habitats In Tooele County, Utah, Steven M. Ostoja, Eugene W. Schupp, Kelly Sivy

Western North American Naturalist

Biological invasions are one of the greatest threats to native species in natural ecological systems. One of the most successful invasive species is Bromus tectorum L. (cheatgrass), which is having marked impacts on native plant communities and ecosystem processes. However, we know little about the effects of this invasion on native animal species in the Intermountain West. Because ants have been used to detect ecological change associated with anthropogenic land use, they seem well suited for a preliminary evaluation of the consequences of cheatgrass-driven habitat conversion. In our study, we used pitfall traps to assess ant community assemblages in intact …

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Planted Grasslands And Native Sod Prairie: Equivalent Habitat For Grassland Birds?, Kristel K. Bakker, Kenneth F. Higgins Jul 2009

Planted Grasslands And Native Sod Prairie: Equivalent Habitat For Grassland Birds?, Kristel K. Bakker, Kenneth F. Higgins

Western North American Naturalist

Little is known about how avian relationships to tracts of native sod prairie compare with avian relationships to single and multiple species of cool- and warm-season grassland plantings. We compared grassland bird species richness and density in 5 grassland cover types (n = 97) in the tallgrass prairie region of eastern South Dakota and western Minnesota, 2001–2004. Grassland bird species richness was significantly higher in native sod prairies than it was in all planted cover types except warm-season mixes. Grasslands dominated by exotic species did not support as many grassland bird species or have species densities as high as …

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Selective Herbivory By The Desert Woodrat (Neotoma Lepida) On Joshua Trees (Yucca Brevifolia), Monte P. Sanford, Nancy Huntly Jul 2009

Selective Herbivory By The Desert Woodrat (Neotoma Lepida) On Joshua Trees (Yucca Brevifolia), Monte P. Sanford, Nancy Huntly

Western North American Naturalist

We studied herbivory by the desert woodrat (Neotoma lepida) on Joshua trees (Yucca brevifolia) in the Mojave Desert to determine whether N. lepida fed selectively based on leaf nitrogen content. We measured leaf nitrogen content and the location and amount of herbivory by woodrats on Y. brevifolia trees in southwestern Utah, USA. Neotoma lepida removed the outer tips of leaves (1/3 to 2/3 of total leaf length) but left leaf bases, which had lower nitrogen content, uneaten. Herbivory by N. lepida also was concentrated on rosettes that were oriented south, and these had significantly higher nitrogen …

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On Differentiating Myotis Yumanensis And Myotis Lucifugus In The Field: A Reply To Carraway, Thomas J. Rodhouse, Shonene A. Scott, Patricia C. Ormsbee, Jan M. Zinck Jul 2009

On Differentiating Myotis Yumanensis And Myotis Lucifugus In The Field: A Reply To Carraway, Thomas J. Rodhouse, Shonene A. Scott, Patricia C. Ormsbee, Jan M. Zinck

Western North American Naturalist

No abstract provided.

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