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Index [And Table Of Contents] To Volume 61

Western North American Naturalist

No abstract provided.

Sexual Dimorphism And Body Temperatures Of Sceloporus Siniferus From Guerrero, México, Julio A. Lemos-Espinal, Geoffrey R. Smith, Royce E. Ballinger

Western North American Naturalist

No abstract provided.

Sasquaperla Hoopa, A New Stonefly Genus And Species From Northern California (Plecoptera: Chloroperlidae), B. P. Stark, R. W. Baumann

Western North American Naturalist

Sasquaperla hoopa, a new genus and species of Chloroperlidae, is described from adults and preemergent nymphs collected in the Coast Range of northern California. Males are characterized by the epiproct reduced to a small, tablike structure bearing stiff hairs in a narrow band along the posterior margin. Females are similar to those of Sweltsa, but the nymphs bear several erect bristles lateral to depressed hair patches on the mesosternum. Modified keys are presented for adults and nymphs.

Experimental Manipulations Of Precipitation Seasonality: Effects On Oak (Quercus) Seedling Demography And Physiology, Jake F. Weltzin, Keirith A. Snyder, David G. Williams

Western North American Naturalist

Predicted changes in regional precipitation patterns and soil moisture caused by anthropogenic trace gas emissions may affect the distribution and abundance of woody plants in arid and semiarid regions. To test the response of woody plants to potential changes in precipitation regimes, we manipulated summer and winter precipitation on plots that contained seedlings of Quercus emoryi Torr. (Emory oak), the dominant tree in oak savannas of the southwestern United States. Throughout the growing season, we monitored seedling survival and physiology (predawn leaf water potential, midday instantaneous gas exchange, and leaf carbon isotope discrimination). Seedling survival and physiological performance differed little …

Notes On The Winter Diet Of Short-Eared Owls In Northern California, Raymond J. Bogiatto, John A. Hindley, Rebecca L. Surles

Western North American Naturalist

No abstract provided.

Full Issue, Vol. 61 No. 4

Western North American Naturalist

No abstract provided.

Modeling The Effects Of Transforming Growth Factor-Beta On Extracellular Matrix Alignment In Dermal Wound Repair, J. C. Dallon, J. A. Sherratt, P. K. Maini

Faculty Publications

We present a novel mathematical model for collagen deposition and alignment during dermal wound healing, focusing on the regulatory effects of TGF. Our work extends a previously developed model which considers the interactions between fibroblasts and extracellular matrix, composed of collagen and a fibrin based blood clot, by allowing fibroblasts to orient the collagen matrix, and produce and degrade the extracellular matrix, while the matrix can direct the fibroblasts and control their speed. Here we extend the model by allowing a time varying concentration of TGF to alter the properties of the fibroblasts. Thus we are able to simulate experiments …

Mormonism And Islam: From Polemics To Mutual Respect And Cooperation, Arnold H. Green

BYU Studies

The world's fastest growing religion is either Islam (if considering annual growth in total numbers) or Mormonism (if considering annual growth in percentage terms). These two rapidly expanding global faiths are certain to increase interactions with each other. Already, in the minds of some clergymen, the two faiths have become associated in several ways, including Mormonism's being called "the Islam of America." While Muslim leaders have so far paid little attention to The Church of Jesus Christ of Latter-day Saints, the Church's General Authorities have expressed opinions about Islam. At first, they reacted negatively to being equated with it. Later, …

Christmas And Childhood, J. R. Kearl

Religious Educator: Perspectives on the Restored Gospel

No abstract provided.

Do You Need To Clear The Air? Indoor Air Quality And Your Family's Health, Maribeth C. Clarke, Carolyn Garrison

Marriage and Families

No abstract provided.

Full Issue, Marriage &. Families

Marriage and Families

No abstract provided.

Defining And Evaluating Exotic Species: Issues For Yellowstone Park Policy, Ned Hettinger

Western North American Naturalist

Exotics are species that are foreign to an ecological assemblage in the sense that they have not significantly adapted to resident biota or to local abiotic conditions, and resident species have not significantly adapted to them. Although they need not be human introduced nor damaging, when they are, a negative appraisal of such exotic species can be justified. Human introduction of exotics into natural systems typically increases human influence over those systems, thus diminishing their wildness. Valuing nature for its wildness is a rationale for the national parks policy of letting nature take its course. Thus, Yellowstone Park has a …

The Naturalness Of Biological Invasions, Daniel B. Botkin

Western North American Naturalist

No abstract provided.

Natural And Unnatural; Wild And Cultural, Holmes Rolston Iii

Western North American Naturalist

Yellowstone National Parks mission and policy can be clarified by analysis of the natural and the unnatural. Nature is a comprehensive word, in some uses excluding nothing; more useful is a contrast distinguishing nature and culture. Specifying "wild nature" denotes spontaneous nature absent human influence. Critics claim that the meaning of wild nature, especially of wilderness, is a foil of culture. Pristine nature, often romanticized, is contrasted with a technological and industrial culture. By this account, wilderness is a social construction.

Nevertheless, wild nature successfully denotes, outside culture, an evolutionary and ecological natural history, which remains present on the Yellowstone …

A Paleoecologic Perspective On Past Plant Invasions In Yellowstone, Cathy Whitlock, Sarah H. Millspaugh

Western North American Naturalist

The role of climate and natural disturbance in the past provides a context for understanding present and future changes in biota. The vegetation history of the Yellowstone region, like that of North America as a whole, is largely one of plant invasions and extinctions in response to changes in climate and environment. When Holocene plant migrations are examined on multiple spatial and temporal scales, several generalities are apparent. First, at a continental and regional scale, plant migration patterns followed the direction of climate change, whereas at local scales plant colonization was governed by site-specific conditions and possibly by biotic interactions. …

Annotated Checklist Of Exotic Vascular Plants In Yellowstone National Park, Jennifer J. Whipple

Western North American Naturalist

Documentation of the arrival of exotic vascular plants in Yellowstone National Park has been sporadic. An annotated checklist of exotic vascular plants is presented, with information about the approximate arrival time in the park of each species and the current extent of the infestation. Yellowstones flora includes 187 exotic vascular plant species (14.8% of the flora), and the park has an extrapolated mean number of exotic species per 10 km² of 47.3. The situation in Yellowstone is compared with other areas in North America. The increase in exotics mirrors a corresponding increase in visitation.

Managing A Complex Exotic Vegetation Program In Yellowstone National Park, Tom Olliff, Roy Renkin, Craig Mcclure, Paul Miller, Dave Price, Dan Reinhart, Jennifer Whipple

Western North American Naturalist

The number of documented exotic plants in Yellowstone National Park has increased from 85 known in 1986 to over 185 today. Exotic plants are substantially impacting the parks natural and cultural resources and are a high management priority. We have adopted an integrated weed management approach with regard to exotic vegetation, emphasizing prevention, education, early detection and eradication, control, and, to a lesser degree, monitoring. The program involves over 140 staff with program expenditures averaging approximately $190,000 annually. Prevention actions include requiring approved gravel on construction projects; banning hay in the backcountry and allowing transport of only certified weed-seed-free hay …

Status And Conservation Of Salmonids In Relation To Hydrologic Integrity In The Greater Yellowstone Ecosystem, Robert W. Van Kirk, Lyn Benjamin

Western North American Naturalist

Native salmonid status was evaluated with an index quantifying distribution and abundance of cutthroat trout (Oncorhynchus clarki) and grayling (Thymallus arcticus) in 41 watersheds comprising the Greater Yellowstone Ecosystem. We assessed hydrologic integrity with a percentile-based index measuring cumulative effects of reservoirs, surface water withdrawals, and consumptive water use. Status of native salmonids was poor in 70% of the watersheds; exceptions occurred in a north-south core extending from the Upper Yellowstone southward through the national parks to Bear Lake. Hydrologic integrity was highest in headwater areas and lowest in lower-elevation watersheds. Status of native and nonnative …

Spatial Distribution Of Three Snail Species, Including The Invader Potamopyrgus Antipodarum, In A Freshwater Spring, David C. Richards, L. Dianne Cazier, Gary T. Lester

Western North American Naturalist

The highly invasive New Zealand mudsnail, Potamopyrgus antipodarum, may compete with and displace native North American macroinvertebrates in freshwater systems wherever it becomes established. Densities and spatial distributions of 3 snail species including P. antipodarum and the threatened Taylorconcha serpenticola were compared among 3 adjacent habitat types (run, edge, and vegetation) in Banbury Springs, a tributary of the Snake River, near Hagerman, Idaho, USA. In all 3 habitats P. antipodarum was the most abundant snail species. All 3 species densities were highly variable within habitats, suggesting a nonrandom distribution pattern. Densities of P. antipodarum were significantly greatest in the …

Biological Invasions—How Are They Affecting Us, And What Can We Do About Them?, Daniel Simberloff

Western North American Naturalist

Nonindigenous species affect native ecosystems, communities, and populations in myriad ways, from plants (and a few animals) that overgrow entire communities, to plants and animals that hybridize individual native species to a sort of genetic extinction. Further, nonindigenous species sometimes interact to worsen each others impact. These impacts are commonly seen in national parks throughout the United States. The key policy change required to alleviate this threat is a shift from blacklists of prohibited species and a presumption of harmlessness to combinations of white and blacklists and a presumption that any species may be damaging. This new guiding philosophy must …

Full Issue, Vol. 61 No. 3

Western North American Naturalist

No abstract provided.

Effects Of Exotic Species On Yellowstone's Grizzly Bears, Daniel P. Reinhart, Mark A. Haroldson, David J. Mattson, Kerry A. Gunther

Western North American Naturalist

Humans have affected grizzly bears (Ursus arctos horribilis) by direct mortality, competition for space and resources, and introduction of exotic species. Exotic organisms that have affected grizzly bears in the Greater Yellowstone Area include common dandelion (Taraxacum officinale), nonnative clovers (Trifolium spp.), domesticated livestock, bovine brucellosis (Brucella abortus), lake trout (Salvelinus namaycush), and white pine blister rust (Cronartium ribicola). Some bears consume substantial amounts of dandelion and clover. However, these exotic foods provide little digested energy compared to higher-quality bear foods. Domestic livestock are of greater energetic value, but …

New Approaches For Sampling And Modeling Native And Exotic Plant Species Richness, Geneva W. Chong, Robin M. Reich, Mohammed A. Kalkhan, Thomas J. Stohlgren

Western North American Naturalist

We demonstrate new multi-phase, multi-scale approaches for sampling and modeling native and exotic plant species to predict the spread of invasive species and aid in control efforts. Our test site is a 54,000-ha portion of Rocky Mountain National Park, Colorado, USA. This work is based on previous research wherein we developed vegetation sampling techniques to identify hot spots of diversity, important rare habitats, and locations of invasive plant species. Here we demonstrate statistical modeling tools to rapidly assess current patterns of native and exotic plant species to determine which habitats are most vulnerable to invasion by exotic species. We use …

The Need For Small Learning Rates On Large Problems, Tony R. Martinez, D. Randall Wilson

Faculty Publications

In gradient descent learning algorithms such as error backpropagation, the learning rate parameter can have a significant effect on generalization accuracy. In particular, decreasing the learning rate below that which yields the fastest convergence can significantly improve generalization accuracy, especially on large, complex problems. The learning rate also directly affects training speed, but not necessarily in the way that many people expect. Many neural network practitioners currently attempt to use the largest learning rate that still allows for convergence, in order to improve training speed. However, a learning rate that is too large can be as slow as a learning …

Improving The Hopfield Network Through Beam Search, Tony R. Martinez, Xinchuan Zeng

Faculty Publications

In this paper we propose a beam search mechanism to improve the performance of the Hopfield network for solving optimization problems. The beam search readjusts the top M (M > 1) activated neurons to more similar activation levels in the early phase of relaxation, so that the network has the opportunity to explore more alternative, potentially better solutions. We evaluated this approach using a large number of simulations (20,000 for each parameter setting), based on 200 randomly generated city distributions of the 10-city traveling salesman problem. The results show that the beam search has the capability of significantly improving the network …

Can Science Be Faith-Promoting? Sterling B. Talmage, Noel L. Owen

BYU Studies

Sterling B. Talmage. Can Science Be Faith-Promoting? Ed. Stan Larson. Salt Lake City: Blue Ribbon Books, 2001. lxiv; 253 pp. Bibliography, index. $18.95.

Restoration Of Fish Habitat In The Provo River: A Multispecies Approach, Mark C. Belk

Faculty Publications

Historically, the Provo river, located in Utah and Wasatch Cos., Utah, was a clear-flowing stream with headwaters in the western edge of the Uinta mountains that emptied into Utah Lake near Provo, Utah. The river had a wide flood plain and a braided channel, especially in the Heber valley and Utah valley areas. Diversion of water and construction of water storage facilities began in the late 1800's and intensified in the 1900's. Deer Creek reservoir was built in the 1950's and diking and channelization continued until the construction of Jordanelle reservoir in the late 1980's. The Provo River Restoration Project, …

Comparative Phylogeography Of Mesoamerican Highland Rodents: Concerted Versus Independent Response To Past Climatic Fluctuations, Duke S. Rogers, Jack Sullivan, Elizabeth Arellano

Faculty Publications

The phylogeography of Sumichrast's harvest mouse (Reithrodontomys sumichrasti) was examined through maximumlikelihood and parsimony analyses of 1,130 bp of mitochondrial Cytochrome b sequence data from 43 individuals. The phylogeography of this Middle American highland forest-dwelling species was compared to that previously published for the codistributed Aztec deer mouse complex (Peromyscus aztecus/Peromyscus hylocetes complex) in order to test competing hypotheses of concerted versus independent responses of codistributed forms to past climatic fluctuations. Qualitatively, there were strong similarities in the phylogeographic patterns of the two groups, yet there were also areas of incongruence. Likelihood-ratio tests (Kishino-Hasegawa-Templeton and parametric bootstrap tests) indicated that …

Comprehensive Isotachophoresis-Capillary Electrophoresis Coupled To Time-Of-Flight Mass Spectrometry, Christopher Ryan Bowerbank

Theses and Dissertations

Isotachophoresis (ITP) coupled to capillary zone electrophoresis (CE) in a comprehensive manner was used to separate mixture components in both insufficient and sufficient concentrations without heart-cutting or splitting. Examples of comprehensive ITP-CE involving multiple CE injections of preconcentrated ITP zones are demonstrated. In the comprehensive arrangement, all of the sample in the first dimension (ITP) is subjected to analysis in the second dimension (CE), without significant sample loss or decrease in sample detectability resulting from removal of a portion of the sample. This is especially important for analytes at low concentrations which may form a single mixed zone instead of …

Occurrence Of Native Colorado River Cutthroat Trout (Oncorhynchus Clarki Pleuriticus) In The Escalante River Drainage, Utah, Dale K. Hepworth, Michael J. Ottenbacher, Charles B. Chamberlain

Western North American Naturalist

Field surveys were conducted during 1997 and 1998 documenting the distribution and abundance of Colorado River cutthroat trout (Oncorhynchus clarki pleuriticus) in Escalante River tributaries. This documented occurrence of native trout in the Escalante River drainage of southern Utah represents an expansion of the known historic range of this subspecies as reported before the 1990s. We found 5 populations of native trout ranging in biomass from 3.0 to 104.2 kg ha⁻¹ and occupying 13.2 km of stream of 130 km of estimated historic habitat. Current distribution and abundance of Colorado River cutthroat trout were compared to early …