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Elaine Morgan. The Scars Of Evolution: What Our Bodies Tell Us About Human Origins., Roger W. Wescott

Comparative Civilizations Review

No abstract provided.

Differential Responses To Nitrogen Form And Concentration For Oryzopsis Hymenoides And Elymus Lanceolatus, Robert S. Nowak, Cheryl L. Nowak, Jay E. Anderson

Great Basin Naturalist

In a greenhouse experiment, effects of nitrogen form and concentration on productivity and dry matter allocation differed between two species native to semiarid ecosystems of the Great Basin. Aboveground production of green surface area and of dry matter were consistently enhanced by increased nitrogen for the rhizomatous grass Elymus lanceolatus, but not for the bunchgrass Oryzopsis hymenoides. These differences were likely due to inherently low growth rates of O. hymenoides. Aboveground dry matter allocation also differed between the two species. O. hymenoides had more leaves per tiller with increased nitrogen, whereas leaf size but not number increased …

Simulation Modeling Of American Marten (Martes Americana) Populations: Vulnerability To Extinction, Robert C. Lacy, Tim W. Clark

Great Basin Naturalist

American marten (Martes americana) are medium-sized mammalian carnivores inhabiting forest communities across northern North America. Martens are susceptible to local extinction from habitat alterations, trapping, and other factors. We (RCL) developed a population model called VORTEX to estimate extinction probabilities for marten populations as a management tool. The model permits managers to simulate various levels of timber harvesting, commercial trapping, and other factors to estimate their effects on marten populations. This paper describes this model and illustrates its benefits by using marten data from the Greater Yellowstone Ecosystem of northwestern Wyoming. Results are preliminary. Populations of 50 and …

Prey Selection And Food Habits Of Burrowing Owls In Colorado, David L. Plumpton, R. Scott Lutz

Great Basin Naturalist

Food habits of Burrowing Owls (Speotyto cunicularia) were studied during the breeding seasons of 1990 and 1991 in central Colorado. Concurrent insect availability studies were conducted to determine selection for specific insect families. Analysis of 1445 castings indicated use of only one insect family, the carrion beetles (Silphidae), at a rate greater than expected based on availability in one year. Castings and prey remains showed different dietary components. Prey remains showed greater use of small mammals, moths, amphibians, and passerines, and castings indicated greater use of mice and beetles. Methodology in raptor food habits studies may therefore bias …

Transport Of A Juvenile Pinyon Mouse (Peromyscus Truei), J. R. Callahan, Daniel S. Compton

Great Basin Naturalist

No abstract provided.

Evidence Of Bison Bison In The Great Basin, Dirk Van Vuren, Frank C. Deitz

Great Basin Naturalist

No abstract provided.

Winter Mortality Of The Russian Wheat Aphid (Homoptera: Aphididae) On Range Grasses In Northern Utah, Frank J. Messina

Great Basin Naturalist

No abstract provided.

Distribution And Abundance Of Birds In The White Mountains, California, Michael L. Morrison, Linnea S. Hall, John J. Keane, Amy J. Kuenzi, Jared Verner

Great Basin Naturalist

This paper quantifies the distribution and abundance of birds in the White Mountains, Inyo and Mono counties, California, during spring–summer 1989–91, to establish a baseline for monitoring the area's avifauna. Overall 58 species were encountered in the single-leaf pinyon–Utah juniper (Pinus monophylla–Juniperus osteosperma) zone, and 61 species in the bristlecone–limber pine (P. longaeva–P. flexilis) zone. The bristlecone–limber pine zone had a significantly greater overall bird abundance relative to the pinyon–juniper. Both zones were characterized by few very abundant species, a few moderately abundant species, and numerous rare species. The Black-throated Gray Warbler (scientific names in tables), …

Full Issue, Vol. 53 No. 3

Great Basin Naturalist

No abstract provided.

Seedling Size And Survival For Chrysothamnus Nauseosus, Lisa A. Donovan, James Mausberg, James R. Ehleringer

Great Basin Naturalist

Seedling size and survival in relation to summer drought were examined for Chrysothamnus nauseosus growing under field and greenhouse conditions. In the field, summer survival rates were less than 2% annually for the three years monitored. The effect of initial seedling height on subsequent survival was examined in both the field and greenhouse by grouping seedlings into live and dead categories on each census date and comparing initial heights for seedlings in these categories. For a majority of the census dates, the initial height of surviving seedlings was greater than the initial height of those that subsequently died (significant differences …

Front Matter, Vol. 53 No. 3

Great Basin Naturalist

No abstract provided.

Depletion Of Soil Moisture By Two Cold-Desert Bunchgrasses And Effects On Photosynthetic Performance, Jay E. Anderson, Nancee L. Toft

Great Basin Naturalist

This study compared the abilities of two cool-season bunchgrasses to extract moisture from a drying soil and compared photosynthetic and stomatal responses of the two species as soil moisture supplies were depleted. When grown in 49-L pots in a greenhouse, Leymus cinereus extracted more water from the soil and maintained higher gas exchange rates to lower absolute amounts of soil water than did Agropyron desertorum. The soil water content at the lower limit of extraction was 10.3% for L. cinereus and 13.3% for A. desertorum. When soil moisture was expressed as extractable soil water, there was little difference …

Use Of Boulder Pocket Habitat By Rainbow Trout (Oncorhynchus Mykiss) In Fall River, Idaho, Daniel N. Streubel, J. S. Griffith

Great Basin Naturalist

Abundance of rainbow trout (Oncorhynchus mykiss) in relation to characteristics of pockets created by boulders was studied in Fall River, southeastern Idaho. To determine depth and surface area of pockets most selected by rainbow trout, fish were counted by snorkeling, and pocket physical dimensions were measured. An electivity index defined habitat selection in the following terms: the most suitable habitat was ≥0.7 m maximum depth, ≥0.5 m minimum depth, and ≥3 in² surface area. Some study reaches of Fall River had more suitable pockets available for trout than were being utilized.

Humoral Creatinine In Walleye (Stizostedion Vitreum), Harry L. Holloway Jr., Craig A. Shoemaker

Great Basin Naturalist

Published fish blood parameters are limited to commercially cultured species (e.g. rainbow trout [Oncorhynchus mykiss] and channel catfish [Ictalurus punctatus]). However, as walleye (Stizostedion vitreum) and other fish increase in value to the angler, hatchery and fish managers will require data on these species. Blood sera were collected from live walleye in the field, creatinine values were determined colorimetrically, and health range values were established from these data. Creatinine levels of walleye serum (0.06–0.72 mg/dl) were higher in three species but lower than recognized in a recent catfish study. Creatinine levels may be important …

Front Matter, Vol. 53 No. 2

Great Basin Naturalist

No abstract provided.

Squirrels As Predators, J. R. Callahan

Great Basin Naturalist

A literature review and field observations indicate that most sciurids are facultative predators on small vertebrates. This behavior is documented for at least 30 sciurid species in 8 genera. The frequency of predation apparently is influenced by various factors including climate, season, gender, reproductive condition, and availability of plant sources for certain nutrients such as calcium and nitrogen. Although sciurids assimilate as much energy from animal foods as do obligate carnivores, behavior associated with predation appears to be less efficient in sciurids and may rely partly on prey habituation and other adaptive behaviors.

Bole Volume Growth In Stems Of Quercus Gambelii, Warren P. Clary, Arthur R. Tiedemann

Great Basin Naturalist

Shrub-form and tree-form Gambel oak (Quercus gambelii) stands contain a potentially significant fuelwood resource. Information on their growth characteristics can form a basis for future stand management. Stem analyses showed that height growth of shrub-form stems essentially ceased after age 50, while tree-form stems continued to increase in height until approximately age 100. Both stem forms continued to increase in basal area and volume at a relatively constant rate as the stems increased in age and size. Increases in all size measures were substantially greater in tree-form stems than in shrub-form stems. Mean bole volume for tree-form stems …

Growth Of Smallmouth Bass (Micropterus Dolomieu) In Flaming Gorge Reservoir, Wyoming–Utah, Scott A. Mullner, Wayne A. Hubert

Great Basin Naturalist

Growth of smallmouth bass (Micropterus dolomieu) was described for three widely spaced areas progressing downstream in Flaming Gorge Reservoir, Wyoming–Utah. Significant differences among areas were detected only for age-1 fish. Growth in the reservoir was compared with that of populations in other lentic habitats of varying growing season lengths in North America; slow growth in the reservoir was related to the relatively short growing season (less than 90 days).

Influence Of Prey Movement On The Aim Of Predatory Strikes Of The Western Rattlesnake (Crotalus Viridis), Douglas F. Schmidt, William K. Hayes, Floyd E. Hayes

Great Basin Naturalist

The purpose of this study was to determine whether the western rattlesnake (Crotalus viridis) aims its predatory strike at the head/thorax region of mice primarily on the basis of cues related to the direction of prey movement. We hypothesized that when rattlesnakes strike at anesthetized, backward-moving mice, most strikes would be aimed at the forward-most-moving region, i.e., the posterior (abdomen/tail) region of prey. However, most mice were struck in the anterior (head/thorax) region, implying that the visual-infrared image of mice, rather than directional movement, guides the aim of predatory strikes.

End Matter, Vol. 53 No. 2

Great Basin Naturalist

No abstract provided.

Full Issue, Vol. 53 No. 2

Great Basin Naturalist

No abstract provided.

On The Relative Importance Of Floral Color, Shape, And Nectar Rewards In Attracting Pollinators To Mimulus, Steven D. Sutherland, Robert K. Vickery Jr.

Great Basin Naturalist

Pollinator preferences were observed for the six species of section Erythranthe of the genus Mimulus using greenhouse-grown plants placed in a meadow in the Red Butte Canyon Natural Area, Salt Lake County, Utah. The principal pollinators were hummingbirds and bumble bees. Hummingbirds preferred the species with the most reflexed tubular flowers regardless of color, whereas bumblebees preferred pink. lavender, or yellow flowers to red flowers regardless of shape. Results for the six species were confirmed by observations of F₂ hybrid recombinant plants selected such that flower color could be held constant and flower shape varied and vice versa.

Late Quaternary Vegetation And Climate In The Escalante River Basin On The Central Colorado Plateau, Kim Withers, Jim I. Mead

Great Basin Naturalist

Five alcoves (rock shelters) in the Forty-Mile Canyon–Willow Gulch area of the Escalante River Basin in southeastern Utah yielded rich deposits of late Quaternary macrobotanical remains. The deposits were sampled and the contents identified in order to construct a chronology of vegetational change. Fourteen radiocarbon dates indicate that the fossils were deposited between 12,690 and 7510 yr B.P. (years before present).

Ninety-one plant taxa were identified, 62 to species. Six species were common to all alcoves: Gambel oak (Quercus gambelii), box-elder (Acer negundo), prickly pear (Opuntia subgenus Platyopuntia), skunkbush (Rhus aromatica var. trilobata), …

Rule Of Law In Legal And Economic Theory, Noel B. Reynolds

Faculty Publications

Legal positivism, the leading version of legal theory, has shown that a concentration on the meanings and logical relations of legal concepts, however much supplemented by intuition, common sense and legal experience, is not adequate to make full sense out of the human experience of law, and the traditional understandings of legal obligation and rule of law in particular. However, modern economic science has advanced a radically individualistic theoretical approach which has propelled economics to the fore as the most successful of the social sciences. And its basic theoretical stance is proving both attractive and adaptable to all the other …

Cyanobacteria And Cyanolichens: Can They Enhance Availability Of Essential Minerals For Higher Plants?, Kimball T. Harper, Rosemary L. Pendleton

Great Basin Naturalist

In both field and greenhouse studies, cyanobacterial and cyanolichens of cold-temperature deserts often enhance growth and essential uptake by associated herbs. That effect is associated with better seedling establishment and larger seedlings. The following are possible mechanisms for these effects: (1) the microbiota concentrate essential elements in available forms in soil surface layers, (2) the microbial surface covers are usually darker colored than the soil itself and produce warmer soils during cool seasons when soil water is most available, (3) the gelatinous sheaths of several cyanobacterial genera common on alkaline deserts contain chelating compounds, and (4) conditions that favor persistent …

Recovery Rates Of Cryptobiotic Crusts: Inoculant Use And Assessment Methods, Jayne Belnap

Great Basin Naturalist

Recovery rates of cyanobacterial-lichen soil crusts from disturbance were examined. Plots were either undisturbed or scalped, and scalped plots were either inoculated with surrounding biological crust material or left to recover naturally. Natural recovery rates were found to be very slow. Inoculation significantly hastened recovery for the cyanobacterial/green algal component, lichen cover, lichen species richness, and moss cover. Even with inoculation, however, lichen and moss recovery was minimal. Traditional techniques of assessing recovery visually were found to underestimate time for total recovery. Other techniques, such as extraction of chlorophyll a from surface soil and measurement of sheath material accumulation, were …

End Matter, Vol. 53 No. 1

Great Basin Naturalist

No abstract provided.

Microbial Spatial Heterogeneity In Microbiotic Crusts In Colorado National Monument. I. Algae, Anne E. Grondin, Jeffrey R. Johansen

Great Basin Naturalist

Spatial heterogeneity in visually similar sites under Utah juniper canopy in Colorado National Monument was examined. Sample sites were arranged in a transect 24 m long, such that distances between samples were 0.013 m, 0.03 m, 1.0 m, 12 m, and 24 m. Twenty-five taxa of algae were observed, mostly belonging to Cyanophyta. Algal density varied by more than an order of magnitude within the 46 samples examined. The coefficients of variation for each distance class were very similar, demonstrating that algal patchiness can be as significant on a scale less than 0.013 m as it is on a scale …

Introduction To The Symposium On Soil Crust Communities, Larry L. St. Clair, Jeffrey R. Johansen

Great Basin Naturalist

Soil crust communities in semiarid and arid lands around the world have received increasing attention in the past two decades. A symposium on their ecology was presented at the annual meeting of the American Bryological and Lichenological Society held in 1991 in San Antonio, Texas. An introduction to the topic and an overview of the papers appearing in the proceedings volume are given in this prologue.

Soil Microstructure In Soils Of The Colorado Plateau: The Role Of The Cyanobacterium Microcoleus Vaginatus, Jayne Belnap, John S. Gardner

Great Basin Naturalist

The role of the cyanobacterium Microcoleus vaginatus in cold-desert soil crusts is investigated using scanning electron microscopy. Crusts from sandstone-, limestone-, and gypsum-derived soils are examined. When dry, polysaccharide sheath material from this cyanobacterium can be seen winding through and across all three types of soil surfaces, attaching to and binding soil particles together. When wet, sheaths and living filaments can be seen absorbing water, swelling and covering soil surfaces even more extensively. Addition of negatively charged material, found both as sheath material and attached clay particles, may affect cation exchange capacity of these soils as well. As a result …