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Brigham Young University

2008

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"Pando" Lives: Molecular Genetic Evidence Of A Giant Aspen Clone In Central Utah, Jennifer Dewoody, Carol A. Rowe, Valerie D. Hipkins, Karen E. Mock Dec 2008

"Pando" Lives: Molecular Genetic Evidence Of A Giant Aspen Clone In Central Utah, Jennifer Dewoody, Carol A. Rowe, Valerie D. Hipkins, Karen E. Mock

Western North American Naturalist

While clones of trembling aspen (Populus tremuloides, Michx.) in the Intermountain West of North America are expected to be large, one putative genet in central Utah, identified from morphological evidence, has garnered particular attention for its size, even gaining the nickname "Pando" (Latin for "I spread"). In order to determine if a single genetic individual coincides with the morphological boundary of "Pando," we sampled 209 stems on a 50-m grid throughout the putative clone for analysis at 7 microsatellite loci. We have identified a single genetic entity concurrent with that described from morphological characteristics. Spatial analyses indicate that the …


Distribution And Status Of The Yellow-Faced Pocket Gopher In Kansas, Justin D. Hoffman, Jerry R. Choate Dec 2008

Distribution And Status Of The Yellow-Faced Pocket Gopher In Kansas, Justin D. Hoffman, Jerry R. Choate

Western North American Naturalist

Previous research suggests that the yellow-faced pocket gopher (Cratogeomys castanops) occupies a restricted range in western Kansas that is surrounded by the range of the plains pocket gopher (Geomys bursarius), which is regarded as a superior competitor. To determine whether the plains pocket gopher has encroached on the range of the yellow-faced pocket gopher in the past 35 years and to better understand the geographic relationships of these species, we trapped pocket gophers in western Kansas and collected soil texture and land cover data. We used ArcView 3.2 to map the distributions of these species in …


Water Stress And Hybridization Between Quercus Gambelii And Quercus Grisea, Nathan G. Swenson, Jeanne M. Fair, Jeff Heikoop Dec 2008

Water Stress And Hybridization Between Quercus Gambelii And Quercus Grisea, Nathan G. Swenson, Jeanne M. Fair, Jeff Heikoop

Western North American Naturalist

The historical and environmental forces involved in determining the geographic location of plant hybrid zones have long been of interest. Often hybrid zones appear to be intimately tied to the environment, yet because many abiotic factors covary it is often difficult to understand which are truly the most important in maintaining the position and structure of a hybrid zone. This study uses empirical data and modeling analyses to examine whether abiotic factors are responsible for the location and structure of an oak (Quercus) hybrid zone and, if so, which factors are the most important. Specifically, leaf trait measurements …


The Biological Soil Crusts Of The San Nicolas Island: Enigmatic Algae From A Geographically Isolated Ecosystem, Valerie R. Flechtner, Jeffrey R. Johansen, Jayne Belnap Dec 2008

The Biological Soil Crusts Of The San Nicolas Island: Enigmatic Algae From A Geographically Isolated Ecosystem, Valerie R. Flechtner, Jeffrey R. Johansen, Jayne Belnap

Western North American Naturalist

Composite soil samples from 7 sites on San Nicolas Island were evaluated quantitatively and qualitatively for the presence of cyanobacteria and eukaryotic microalgae. Combined data demonstrated a rich algal flora with 19 cyanobacterial and 19 eukaryotic microalgal genera being identified, for a total of 56 species. Nine new species were identified and described among the cyanobacteria and the eukaryotic microalgae that were isolated: Leibleinia edaphica, Aphanothece maritima, Chroococcidiopsis edaphica, Cyanosarcina atroveneta, Hassallia californica, Hassallia pseudoramosissima, Microchaete terrestre, Palmellopsis californicus, and Pseudotetracystis compactis. Distinct distributional patterns of algal taxa existed among sites on the island and among soil algal floras of …


Distribution, Abundance, And Genetic Population Structure Of Wood River Sculpin, Cottus Leiopomus, Kevin A. Meyer, Daniel J. Schill, Matthew R. Campbell, Christine C. Kozfkay Dec 2008

Distribution, Abundance, And Genetic Population Structure Of Wood River Sculpin, Cottus Leiopomus, Kevin A. Meyer, Daniel J. Schill, Matthew R. Campbell, Christine C. Kozfkay

Western North American Naturalist

The Wood River sculpin Cottus leiopomus is endemic to the Wood River Basin in central Idaho and is a nongame species of concern because of its limited distribution. However, status and genetic population structure, 2 factors often central to the conservation and management of species of concern, have not been assessed for this species. We used backpack electrofishers to survey streams that were small enough (i.e., <10 m wide) to collect quantitative distribution and abundance data for Wood River sculpin, and we used mitochondrial DNA control region sequencing to investigate the distribution of genetic variation across the species' range. Of the 102 study sites surveyed, 20 sites (20%) had Wood River sculpin present, including 50%, 15%, and 0% of the sites predicted a priori to contain, possibly contain, or not contain the sculpin, respectively. Native redband trout Oncorhynchus mykiss gairdneri were present at 21 study sites, including 18 of the 20 sites that contained Wood River …


Sex Ratios Of The White-Tailed Antelope Ground Squirrel (Ammospermophilus Leucurus), Indian Wells Valley, San Bernardino County, California, Charles J. Randel Iii, Howard O. Clark Jr. Dec 2008

Sex Ratios Of The White-Tailed Antelope Ground Squirrel (Ammospermophilus Leucurus), Indian Wells Valley, San Bernardino County, California, Charles J. Randel Iii, Howard O. Clark Jr.

Western North American Naturalist

We studied the white-tailed antelope ground squirrel during spring and summer 2006 to determine young-of-the-year and adult sex ratios in the Indian Wells Valley, San Bernardino County, California. We calculated a young-of-the-year sex ratio of 1.45:1 (female to male), whereas the adult sex ratio was approximately 1:1. Our young-of-the-year sex ratio was greater than the 1.1:1 (female to male) natal sex ratio previously reported. Differences between young-of-the-year and adult sex ratios may represent low female young-of-the-year survivorship in the Indian Wells Valley.


Unnatural Landscapes: Tracking Invasive Species By Ceiridwen Terrill, Howard O. Clark Jr. Dec 2008

Unnatural Landscapes: Tracking Invasive Species By Ceiridwen Terrill, Howard O. Clark Jr.

Western North American Naturalist

No abstract provided.


Field Identification Of Myotis Yumanensis And Myotis Lucifugus: A Morphological Evaluation, Thomas J. Rodhouse, Shonene A. Scott, Patricia C. Ormsbee, Jan M. Zinck Dec 2008

Field Identification Of Myotis Yumanensis And Myotis Lucifugus: A Morphological Evaluation, Thomas J. Rodhouse, Shonene A. Scott, Patricia C. Ormsbee, Jan M. Zinck

Western North American Naturalist

Myotis lucifugus and Myotis yumanensis are 2 species of bats subject to potentially high rates of misidentification because they are often difficult to differentiate in the hand under field conditions. We tested the utility of a suite of external morphological characteristics frequently cited in regional keys to differentiate the 2 species in the field. Forearm length, dorsal pelage sheen, ear color, and forehead slope were examined from 101 bats captured in central Oregon during 2002–2003. Post hoc genetic analysis was performed on tissue samples collected from the 101 bats to confirm identification. Forearm lengths overlapped considerably between species. Only 18% …


Effects Of Rotational Grazing On Rodents And Raptors In A Coastal Grassland, Matthew D. Johnson, Christa M. Horn Dec 2008

Effects Of Rotational Grazing On Rodents And Raptors In A Coastal Grassland, Matthew D. Johnson, Christa M. Horn

Western North American Naturalist

We conducted a 4-year experiment to assess the impacts of rotational cattle grazing on rodents and raptors in a mesic coastal grassland in northwestern California. Live-trapping indicated that rodent abundance declined by 69% on the grazed area and increased by 14% on the ungrazed area. Raptor use of the grazed area declined by 15% and increased on the ungrazed area by 63%. Measures of giving-up density indicated that rodents perceived a 25% higher predation risk on grazed area than on ungrazed area, but raptor hunting surveys indicated that risk of depredation from raptors was 2.5 times lower in the grazed …


Optimal Temperatures For Growth And Upper Thermal Tolerance Of Juvenile Northern Leatherside Chub, Eric J. Billman, Eric J. Wagner, Ronney E. Arndt, Erin Vandyke Dec 2008

Optimal Temperatures For Growth And Upper Thermal Tolerance Of Juvenile Northern Leatherside Chub, Eric J. Billman, Eric J. Wagner, Ronney E. Arndt, Erin Vandyke

Western North American Naturalist

We examined optimal temperatures for growth and the upper thermal tolerance of juvenile northern leatherside chub (Lepidomeda copei). We conducted 2 experiments using the acclimated chronic-exposure method to estimate optimal temperature for growth of age-0 northern leatherside chub (range 12.8–28.3 °C). Upper thermal tolerance was estimated using the critical thermal maximum (CTM) and upper incipient lethal temperature (UILT) methods for fish acclimated at 15, 18, 23, and 28 °C. We also measured stream temperatures in Yellow Creek, Summit County, Utah, during July–August 2006 to compare our results to actual summer stream temperatures. Survival in growth tests was not …


Diet And Sexual Dimorphism Of The Desert Iguana, Dipsosaurus Dorsalis, From Sonora, Mexico, Christopher J. Dibble, Geoffrey R. Smith, Julio A. Lemos-Espinal Dec 2008

Diet And Sexual Dimorphism Of The Desert Iguana, Dipsosaurus Dorsalis, From Sonora, Mexico, Christopher J. Dibble, Geoffrey R. Smith, Julio A. Lemos-Espinal

Western North American Naturalist

We examined the diet and sexual dimorphism of the desert iguana, Dipsosaurus dorsalis, from Sonora, Mexico. The diet consisted primarily of vegetation, with insect material contributing little to the overall volume of the diet. Plant matter was restricted to leaves and seeds. Animal prey consisted mostly of ants, termites, and beetles. Males and females did not differ significantly in snout–vent length, head length, or head width. These results confirm that in general D. dorsalis is herbivorous and not sexually dimorphic through much of its range.


Examinamos la dieta y dimorfismo sexual de la Iguana del Desierto, Dipsosaurus dorsalis, en Sonora, …


Gizzard Shad (Dorosoma Cepedianum) Expansion And Reproduction In The Upper Colorado River Basin, Sam T. Finney, Mark H. Fuller Dec 2008

Gizzard Shad (Dorosoma Cepedianum) Expansion And Reproduction In The Upper Colorado River Basin, Sam T. Finney, Mark H. Fuller

Western North American Naturalist

Gizzard shad (Dorosoma cepedianum) were introduced into the Colorado River Basin circa 1996 via an unintentional contaminated stocking. Gizzard shad were collected throughout much of the Upper Colorado River Basin in 2005, 2006, and 2007. These collections document a rapid range expansion of this introduced species and a threat to intact fisheries.


New Distributional Records Of The Red Squirrel (Tamiasciurus Hudsonicus) In Western New Mexico And Evidence For Its Extirpation From The Zuni Mountains, Jennifer K. Frey Dec 2008

New Distributional Records Of The Red Squirrel (Tamiasciurus Hudsonicus) In Western New Mexico And Evidence For Its Extirpation From The Zuni Mountains, Jennifer K. Frey

Western North American Naturalist

In the American Southwest, the red squirrel (Tamiasciurus hudsonicus) occurs as disjunct populations in coniferous forests on mountaintops. There is a paucity of information concerning the species' distribution and habitat in western New Mexico. I report new records that document and verify the occurrence of red squirrels in additional montane areas in west central New Mexico, including the Mangas Mountains, Canovas Rim, Turner Mountain, Tularosa Mountains, Elk Mountains, Bearwallow Mountain, and Pinos Altos Mountains. I also report observations of red squirrels from an atypical habitat—low-elevation riparian forests. These new records suggest that the geographic distribution of the species …


Introduction To California Birdlife By Jules Evens And Ian Tait, Clayton M. White Dec 2008

Introduction To California Birdlife By Jules Evens And Ian Tait, Clayton M. White

Western North American Naturalist

No abstract provided.


Erratum Dec 2008

Erratum

Western North American Naturalist

No abstract provided.


End Matter, Vol. 68 No. 4 Dec 2008

End Matter, Vol. 68 No. 4

Western North American Naturalist

No abstract provided.


Short-Term Effects Of Wildfire On Montane Stream Ecosystems In The Southern Rocky Mountains: One And Two Years Post-Burn, Sharon J. Hall, Danica Lombardozzi Dec 2008

Short-Term Effects Of Wildfire On Montane Stream Ecosystems In The Southern Rocky Mountains: One And Two Years Post-Burn, Sharon J. Hall, Danica Lombardozzi

Western North American Naturalist

The frequency and intensity of wildfire in the western United States has increased over the last century, creating a heterogeneous mosaic of landscapes in various stages of recovery. The 2002 Hayman Fire was one of the largest wildfires in Colorado history and was unprecedented for its speed and intensity, with over 50%–70% of the burn area classified as moderate to high severity where much of the canopy crown was consumed. We evaluated the short-term impact of the Hayman Fire on ecological properties in montane stream ecosystems in the summers of 2003 and 2004, one and two years post-fire. Fire significantly …


Reproduction By June Sucker In A Refuge Population: Successful Spawning In A Lake Habitat, Eric J. Billman Dec 2008

Reproduction By June Sucker In A Refuge Population: Successful Spawning In A Lake Habitat, Eric J. Billman

Western North American Naturalist

The June sucker (Chasmistes liorus) is an endangered lake sucker endemic to Utah Lake, Utah. As part of recovery actions, June suckers were introduced into Red Butte Reservoir, Utah, as a wild grow-out site. Since their introduction, June suckers have successfully reproduced in Red Butte Reservoir, producing a large population in this refuge. I used passive egg collectors (egg traps and nets) and observational surveys to determine the location of spawning sites within the reservoir, and larval light trapping to determine successful recruitment (i.e., egg survival through larval swim-up) at these sites. Eggs were collected between 18 June …


Front Matter, Vol. 68 No. 4 Dec 2008

Front Matter, Vol. 68 No. 4

Western North American Naturalist

No abstract provided.


The Relationship Between Nonword Repetition Performance And Social Behaviors In 7- To 11-Year-Old Children With Language Impairment, Bethany Lynne Hillary Dec 2008

The Relationship Between Nonword Repetition Performance And Social Behaviors In 7- To 11-Year-Old Children With Language Impairment, Bethany Lynne Hillary

Theses and Dissertations

Recent literature has suggested a link between verbal working memory and language impairment (LI) in children. There is limited research, however, about the link between verbal working memory and social behaviors in children with LI. This study was designed to explore the relationship between social behaviors (measured by the Teacher Behavior Rating Scale; Hart & Robinson, 1996) and verbal working memory abilities (measured by a 3-, 4-, and 5-syllable nonword repetition task) in children with LI. Thirty-six children (18 with LI and 18 typically developing) aged 7 to 11 years participated in the study. Children with LI were rated by …


Towards The Total Synthesis Of Thioviridamide: Thiyl Radical Approach To The Beta-Thioenamide Linkage Formation, Jung-Hoon Kang Dec 2008

Towards The Total Synthesis Of Thioviridamide: Thiyl Radical Approach To The Beta-Thioenamide Linkage Formation, Jung-Hoon Kang

Theses and Dissertations

We developed an approach to the β-thioenamide linkage contained in the S-(2-aminovinyl)cysteine (avCys) residue of thioviridamide.1,2 Kinetic and thermodynamic control of radical additions of thiols to ynamides were studied for the formation of β-thioenamide linkage. Thiyl radicals are electrophilic and ynamides are electron-rich alkynes. This complementary polarity of the radical and acceptor increases the likelihood of a successful radical addition reaction. Because little is known about these types of compounds (β-thioenamides), we were unsure what kinds of yields and stereoselectivities (cis vs. trans) to expect. The adduct stability is another issue to consider. Fortunately, under typical radical addition conditions, the …


Attitude Estimation And Maneuvering For Autonomous Obstacle Avoidance By Miniature Air Vehicles, James K. Hall Dec 2008

Attitude Estimation And Maneuvering For Autonomous Obstacle Avoidance By Miniature Air Vehicles, James K. Hall

Theses and Dissertations

Utilizing the Euler-Rodrigues symmetric parameters (attitude quaternion) to describe vehicle orientation, we develop a multiplicative, nonlinear (extended) variation of the Kalman filter (MEKF) to fuse data from low-cost sensors. The sensor suite is comprised of gyroscopes, accelerometers, and a GPS receiver. In contrast to the common approach of using the complete vehicle attitude as the quantities to be estimated, our filter states consist of the three components of an attitude error vector. In parallel with the time update of the attitude error estimate, we utilize the gyroscope measurements for the time propagation of the attitude quaternion. The accelerometer and the …


Parentage Statements And Paired Stelae: Signs Of Dynastic Succession For The Classic Maya, Daniel Moroni Stewart Dec 2008

Parentage Statements And Paired Stelae: Signs Of Dynastic Succession For The Classic Maya, Daniel Moroni Stewart

Theses and Dissertations

The purpose of this thesis is to describe and document parentage statements and paired stela found on Maya monuments or portable objects. While the existence of parentage statements, within the Maya text, has been known since the late 1970s, no thesis or major research project has ever been published pertaining to this class of glyphs within the Maya script. In 1977 Christopher Jones is credited with the discovery of parentage statements in Maya hieroglyphic texts (Jones 1977). His discovery was followed by a detailed analysis of parentage statements by Floyd Lounsbury, Peter Mathews, and Linda Schele (1977). They introduced most …


Parental Hesitation As A Factor In Delayed Childhood Immunization, Karlen E. (Beth) Luthy, Renea L. Beckstrand, Neil E. Peterson Dec 2008

Parental Hesitation As A Factor In Delayed Childhood Immunization, Karlen E. (Beth) Luthy, Renea L. Beckstrand, Neil E. Peterson

Faculty Publications

Introduction: One reason for lower immunization rates is that some parents hesitate to have their children immunized. A hesitancy questionnaire was developed to identify reasons parents hesitate in having their children immunized.

Methods: The hesitancy questionnaire was distributed from local pediatric and family practice offices and from the area's county health department. To be eligible, participants needed to be present in the clinic with a child needing a minimum of one immunization that was at least 6 months overdue.

Results: When questioned why their child was overdue for immunizations, the most common response was that participants were confused about the …


Utilitizing And Moving Beyond A Constructionist Approach To Trace The Emergence Of Racial And Ethnic Identities Among Pre-Mexican, Mexican And Americans Of Mexican Descent, Owen Williamson Dec 2008

Utilitizing And Moving Beyond A Constructionist Approach To Trace The Emergence Of Racial And Ethnic Identities Among Pre-Mexican, Mexican And Americans Of Mexican Descent, Owen Williamson

Theses and Dissertations

Cornell and Hartmann (2007) developed a constructionist framework that can describe the development of racial and ethnic identities. Yet this framework has greater utility than its authors have intended as it also provides the best rubric to date for comprehending the transitions between collective identity group types. This study engages in a thorough investigation of the development of racial and ethnic identities within the context of those that precede it via an ethnohistorical analysis. It also demonstrates that this framework is capable of describing pre-modern religious and national identity types in addition to racial and ethnic identity types. This permits …


Developing Writing Fluency Through Synchronous Computer-Mediated Communication, Rossana Camacho Dec 2008

Developing Writing Fluency Through Synchronous Computer-Mediated Communication, Rossana Camacho

Theses and Dissertations

Drawing from sociocultural theory, this research investigated the effects of synchronous computer-mediated communication (SCMC) in the development of writing fluency. Likewise, the study aimed at confirming previously cited affective benefits linked to SCMC. Measuring fluency in words per 30 minutes, the study compared pre and post-test essay scores of two groups of ESL learners (a control group and a SCMC group) in two intermediate levels. Two evaluation questionnaires were also administered to the SCMC group in order to obtain students' opinions of this technology-based medium, and to analyze change in their perceptions. The SCMC group outperformed the control group in …


Improving Library Searches Using Word-Correlation Factors And Folksonomies, Maria Soledad Pera Dec 2008

Improving Library Searches Using Word-Correlation Factors And Folksonomies, Maria Soledad Pera

Theses and Dissertations

Libraries, private and public, offer valuable resources to library patrons; however, formulating library queries to retrieve relevant results can be difficult. This occurs because when using a library catalog for library searches, patrons often do not know the exact keywords to be included in a query that match the rigid subject terms (chosen by the Library of Congress) or terms in other fields of a desired library catalog record. These improperly formulated queries often translate into a high percentage of failed searches that retrieve irrelevant results or no results at all. This explains why frustrated library patrons nowadays rely on …


Ontology Generation, Information Harvesting And Semantic Annotation For Machine-Generated Web Pages, Cui Tao Dec 2008

Ontology Generation, Information Harvesting And Semantic Annotation For Machine-Generated Web Pages, Cui Tao

Theses and Dissertations

The current World Wide Web is a web of pages. Users have to guess possible keywords that might lead through search engines to the pages that contain information of interest and browse hundreds or even thousands of the returned pages in order to obtain what they want. This frustrating problem motivates an approach to turn the web of pages into a web of knowledge, so that web users can query the information of interest directly. This dissertation provides a step in this direction and a way to partially overcome the challenges. Specifically, this dissertation shows how to turn machine-generated web …


Characterization Of The Thermal Transport Through A Temporally-Varying Ash Layer, Darron Palmer Cundick Dec 2008

Characterization Of The Thermal Transport Through A Temporally-Varying Ash Layer, Darron Palmer Cundick

Theses and Dissertations

Ash deposits in commercial coal-fired boilers frequently pose serious maintenance challenges and decrease thermal efficiency. A better understanding of fundamental thermal transport properties in ash deposits can help mitigate their negative effects. In order to characterize the thermal properties of boiler-side deposits, this work presents a thermal transport model and in-situ measurements of effective thermal conductivity in coal ash deposits. A simple model of the thermal transport through an ash deposit, with and with out slagging, was developed. The model approximates the deposit by dividing it into four regimes: particulate, sintered, solidified slag, and molten slag. The development of this …


Comparison Of Two Training Programs On Acceleration Out Of The Break In American Football, Micah Adam Alba Dec 2008

Comparison Of Two Training Programs On Acceleration Out Of The Break In American Football, Micah Adam Alba

Theses and Dissertations

Athletes of American football need the ability to stop, start, and reach top speed in an efficient manner. Football players on the defensive side of the ball require the skill of stopping a backward run and accelerating to a forward run. This action is termed the break. Football players receive year-round training in an effort to improve performance. Yet, many times, these athletes may not focus specifically on the muscular systems that are unique to the position they play. The law of specificity states that the more specific the training is for the action required, the more beneficial the outcome. …