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Distribution And Abundance Of The Black-Billed Magpie (Pica Pica) In North America, Carl E. Bock, Larry W. Lepthien Sep 1975

Distribution And Abundance Of The Black-Billed Magpie (Pica Pica) In North America, Carl E. Bock, Larry W. Lepthien

Great Basin Naturalist

Analysis of Audubon Society Christmas bird count data and certain environmental variables shows the degree to which the Black-billed Magpie is a bird of cool arid regions in North America. The abundance and distribution of this species appear to be limited by two major climatic barriers: increasing summer temperatures in the Southwest and increasing summer humidity and precipitation on the central plains.


Urosaurus And Its Phylogenetic Relationship To Uta As Determined By Osteology And Myology (Reptilia: Iguanidae), Charles Fanghella, David F. Avery, Wilmer W. Tanner Sep 1975

Urosaurus And Its Phylogenetic Relationship To Uta As Determined By Osteology And Myology (Reptilia: Iguanidae), Charles Fanghella, David F. Avery, Wilmer W. Tanner

Great Basin Naturalist

The status of the genus Urosaurus Hallowell and its relationship to the genus Uta Baird and Girard as presented in previous studies are reviewed. Additional data from the head and throat osteology and myology are included in the analysis. Each bone and muscle is measured, ratios determined, and the position noted. Five distinct anatomical differences are noted between Uta and Urosaurus, and it is concluded that both of these genera are sufficiently different to warrant generic status. Uta is considered to be phylogenetically more primitive.


End Matter, Vol. 20 No. 3 Sep 1975

End Matter, Vol. 20 No. 3

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


Mallophaga Of Venezuelan Mammals, K. C. Emerson, Roger D. Price Sep 1975

Mallophaga Of Venezuelan Mammals, K. C. Emerson, Roger D. Price

Brigham Young University Science Bulletin, Biological Series

Seven species of Mallophaga have been previously reported from Venezuelan mammals. In this paper an additional 28 species and subspecies, 7 of which are new, are reported from Venezuela; and 21 other species which have not been previously reported from Venezuela are included because their hosts are found there.


Front Matter, Vol. 20 No. 3 Sep 1975

Front Matter, Vol. 20 No. 3

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


The Effect Of Altitude On Thyroid Function Of The Uinta Ground Squirrel (Citellus Armatus), Wendell Lee Wells Aug 1975

The Effect Of Altitude On Thyroid Function Of The Uinta Ground Squirrel (Citellus Armatus), Wendell Lee Wells

Theses and Dissertations

Thyroid uptake and distribution of 125I, concentrations of T4 and T3 in serum and thyroids and concentrations of TSH in serum and pituitaries were measured to determine thyroid function of Uinta Ground Squirrels (Citellus armatus) native to 5,400 and 9,000 feet elevations to evaluate alterations in the state of the thyroid due to increased altitude. Uptake of 125I was 60 percent lower by squirrels from 9,000 feet. Incorporation of 125I into T3 was greater at the higher elevation, but absolute thyroid T3 concentrations were similar at both elevations. No significant differences were found in serum T3 concentrations, but squirrels living …


The Effects Of Certain Steroids On The Growth Of Slime Mold, Physarum Polycephalum, Ching-Bun Paul Chen Aug 1975

The Effects Of Certain Steroids On The Growth Of Slime Mold, Physarum Polycephalum, Ching-Bun Paul Chen

Theses and Dissertations

The cortex of vertebrate adrenal glands secretes two major groups of hormones--glucocorticoids and mineralocorticoids. Glucocorticoids, which have an oxygen atom at carbon number 11, increase the rate of gluconeogenesis and increase the mobilization of lipids in mammals (Turner and Bagnara 1971). At the same time there is a decrease in protein synthesis. This latter effect may be homologous to a decrease in fibroblast growth in culture in the presence of certain corticosteroids (Ruhmann and Berliner 1965). The main function of mineralocorticoids, on the other hand, is to retain sodium ions. They have little or no gluconeogenic activity. Interestingly, however, these …


The Effect Of Recreational Uses On Vegetation And Soil In The Buffalo Campground, Targhee National Forest, Island Park, Idaho, Susan Daines Foster Aug 1975

The Effect Of Recreational Uses On Vegetation And Soil In The Buffalo Campground, Targhee National Forest, Island Park, Idaho, Susan Daines Foster

Theses and Dissertations

The effect of trampling on vegetation and soil, as a result of recreational pressure, was studied in the Buffalo campground of the Targhee National Forest, Idaho. Site deterioration was most evident in the forty-two year old site. The tree stand had matured, but there were few young trees and tree reproduction had been reduced to ten seedlings per acre for Pinus contorta. Only two shrub species were sampled with a combined population of eight individuals per acre. Most of the grass species had been seeded; forbs provided 20% of the ground cover, 13% was bare ground and 71% litter. The …


The Effect Of Lead And Zinc On Selenium Poisoning In Mice, Cynthia Joy Call Aug 1975

The Effect Of Lead And Zinc On Selenium Poisoning In Mice, Cynthia Joy Call

Theses and Dissertations

Trace elements, because they are effective in catalytic amounts, must be held in delicate balance with each other as well as with the macronutrients of the diet. Disturbances of these balances result in deficiency and toxicity symptoms. Toxic doses of selenium, lead, and zinc, for example, are known to cause anemia (1, 2, 3, 4) and growth depression (5, 3) in experimental animals.


Macrocyclic Polyether Sulfide Syntheses :|Bthe Preparation Of Thia-Crown-6, 7, And 8 Compounds, Robert Askew Reeder Aug 1975

Macrocyclic Polyether Sulfide Syntheses :|Bthe Preparation Of Thia-Crown-6, 7, And 8 Compounds, Robert Askew Reeder

Theses and Dissertations

Macrocyclic polyether sulfides have been prepared by reacting an oligoethylene glycol dichloride with a dithiol in refluxing basic ethanol. The following new compounds were prepared: 1,5-dithia-(19- crown-6), 3-hydroxy-1,5-dithia-(19-crown-6), 1,4-dithia-(21-crown-7), 3-hydroxy-1,5-dithia-(22-crown-7), and 1,4-dithia-(24-crown-8). One other previously reported macrocyclic polyether sulfide was also prepared. The thesis includes a review of macrocyclic sulfides and other related compounds, the thermodynamics of interaction of several macrocyclic polyether sulfides with Ag^+, Hg^2+, and Pb^2+ ions, and a discussion of the structure of these materials.


Habitat Partitioning In A Community Of Passerine Birds, Robert C. Whitmore Aug 1975

Habitat Partitioning In A Community Of Passerine Birds, Robert C. Whitmore

Theses and Dissertations

Habitat partitioning was studied in a community of passerine birds in the Virgin River Valley of southwestern Utah. Ten habitat structure variables were measured for each of 24 species of passerine birds and several multivariate statistical techniques were used to determine the extent of habitat partitioning. Ordinations of species distributions along known environmental gradients were constructed using Principal Component Analysis and Stepwise Discriminant Analysis. Stepwise Discriminant Analysis was also used to determine which habitat variables were important in species separation. It was found that percent canopy cover was the most important variable. Two hundred seventy six pairs of species were …


Analysis Of Macroinvertebrate Samples From Ten Rocky Mountain Streams, Fred A. Mangum Aug 1975

Analysis Of Macroinvertebrate Samples From Ten Rocky Mountain Streams, Fred A. Mangum

Theses and Dissertations

This study was an attempt to evaluate the effects on ten Rocky Mountain streams from management activities on U.S. Forest Service lands. Macroinvertebrate and water chemistry data were collected. Data analysis methods included: three diversity indices, a numerical taxonomy system of multivariate statistical analysis, numbers and biomass per selected taxa, percent composition per order, and total numbers and biomass. None of the methods of analysis were found to be adequate if used alone, but by using a combination of dendograms, biomass, and numbers data in addition to the diversity indices (SCI and d) stream stress could be detected. Although organic …


Timpanogos Flora, Kelly W. Allred Aug 1975

Timpanogos Flora, Kelly W. Allred

Theses and Dissertations

A comprehensive floristic study of Mt. Timpanogos, Utah County, Utah, was undertaken. The Mt. Timpanogos area is a much used facility in recreation, biology, watershed development, livestock management, and education. It is also representative of a major segment of the overall flora of Utah. This study adds to the ever-increading knowledge of the flora of Utah, and provides a means of identifying the flora of this region, which is basic to any future management.


Bionomics Of Two Bark Beetles : Genus Chaetophloeus (Coleoptera : Scolytidae), John Wendell Aaron Aug 1975

Bionomics Of Two Bark Beetles : Genus Chaetophloeus (Coleoptera : Scolytidae), John Wendell Aaron

Theses and Dissertations

Shrubs are important as browse and cover for game animals and songbirds in the desert-shrub and chaparral plant communities in the Great Basin (Plummer, 1968). They also play a major role in soil binding and watershed maintenance (Colby and Weissert, 1975). Therefore, an understanding of the agents which affect the health and survival of the shrubs is important. Insects-have a great impact on the health and reproductive capacity of shrubs. Pollinators, defoliators, borers, etc. must be studied and known for proper management.


Two New Species Of The Genus Cycadeoidea From The Lower Cretaceous Of Utah, H. Blaine Furniss Jul 1975

Two New Species Of The Genus Cycadeoidea From The Lower Cretaceous Of Utah, H. Blaine Furniss

Theses and Dissertations

Cyadeoidea medullara and C. cleavelandii, two new species of the genus Cycadeoidea, have been recovered from the Lower Cretaceous Cedar Mountain Formation of Utah. They have been described in histologic detail and relationships with similar species are set forth. Monoecism and pollination mechanisms have been discussed in connection with C. medullara. This data contributes to our knowledge of the diverse composition of Lower Cretaceous floras in Utah.


The Subfamily Leeuwenhoekinae In The Neotropics (Acarina: Trombiculidae), Jack T. Reed, James M. Brennan Jul 1975

The Subfamily Leeuwenhoekinae In The Neotropics (Acarina: Trombiculidae), Jack T. Reed, James M. Brennan

Brigham Young University Science Bulletin, Biological Series

Neotropical representatives of the subfamily Leeuwenhoekinae are reviewed. The genus Odontacarus comprises 66 percent of the chiggers examined, and 82 percent of this genus were identified as O. tubercularis (Brennan). The following genera are redescribed: Albeckia Veracammen-Grandjean and Watkins, Leeuwenhoekia Oudemans, Odontacarus Ewing, Sasacarus Brennan and Jones, Wagenaaria Brennan, and Whartonia Ewing. New taxa are: Odontacarus comosus comosus, O. c. novemsetus, O. dienteslargus, O. pugnosus, O. schoenesetosus, O. sunnianae, O. tiptoni, O. tuberculohirsutus, O. vanderhammeni, O. vergrandi, Sasacarus furmani panamensis, and Whartonia angulascuta. Odontacarus fieldi Brennan and Jones, 1961, and O. cayolargoensis Brennan, 1959, are synonymized under O. tubercularis Brennan, …


End Matter, Vol. 20 No. 1 Jul 1975

End Matter, Vol. 20 No. 1

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


A List Of Venezuela Chiggers, Particularly Of Small Mammalian Hosts (Acarina: Trombiculidae), James M. Brennan, Jack T. Reed Jul 1975

A List Of Venezuela Chiggers, Particularly Of Small Mammalian Hosts (Acarina: Trombiculidae), James M. Brennan, Jack T. Reed

Brigham Young University Science Bulletin, Biological Series

Detailed or summarized records of 136 species in 38 genera with a key to the latter are provided. Of 86 described forms, 49 are new for Venezuela; the remaining undescribed taxa are coded for purposes of this report. A classified host-parasite list is appended.


Front Matter, Vol. 20 No. 1 Jul 1975

Front Matter, Vol. 20 No. 1

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


Computerized Reduction Of Meteorologic Measurements From Irrigated And Nonirrigated Plots In Central Utah, Ferron L. Andersen, Paul R. Roper Jun 1975

Computerized Reduction Of Meteorologic Measurements From Irrigated And Nonirrigated Plots In Central Utah, Ferron L. Andersen, Paul R. Roper

Great Basin Naturalist

Two FORTRAN IV computer programs were developed to facilitate reduction of meteorologic data from irrigated and nonirrigated plots at Provo, Utah. The first program compiles and tabulates daily, monthly, and yearly summaries of precipitation as rain and/or snow, snowfall, total snow cover, soil moisture, dew, relative humidity, potential evaporation, cloud cover, and wind. Temperature values are tabulated for measurements taken in a standard weather shelter. 5 cm beneath soil surface under grass cover, at soil surface under grass cover, and on bare ground.

The second program enables complete computerized (Calcomp) construction, labeling, and graphing of 10 different meteorologic measurements and …


Rodent Populations, Biomass, And Community Relationships In Artemisia Tridentata, Rush Valley, Utah, D. W. Nichols, H. D. Smith, M. F. Baker Jun 1975

Rodent Populations, Biomass, And Community Relationships In Artemisia Tridentata, Rush Valley, Utah, D. W. Nichols, H. D. Smith, M. F. Baker

Great Basin Naturalist

Three desert Artemisia tridentata communities in Rush Valley, Utah, were trapped for small rodents during the summer of 1970, and population densities were estimated for each population category using Lincoln's index. Animals were weighed and rodent biomass calculated by species throughout the summer. Population, biomass, and other data were then analyzed to gain an understanding of the community relationships of the three study areas to each other as well as to the A. tridentata community types of the Great Basin.

Peromyscus maniculatus, Eutamias minimus, and Reithrodontomys megalotis were common to area 1, whereas P. maniculatus, E. minimus, and Perognathus parvus …


Raptor Temperature Regulation And Energetics, James Arthur Mosher May 1975

Raptor Temperature Regulation And Energetics, James Arthur Mosher

Theses and Dissertations

A review of energetics studies of raptorial species introduces four separate studies of temperature regulation by raptors. Golden Eagle (Aquila chrysaetos) nest site selection, as influenced by direction of exposure, is discussed. The data show strong directional preferences to the NNW by southern populations and SSE by northern populations. The tarsometatarsus is shown to have a thermoregulatory function in large falcons, and adaptations of this mechanism to varied habitats are examined. Color phase in Screech Owls (Otus asio) is shown to be related to metabolic differences that may explain the distributions of the color morphs. Development of thermoregulation in Flammulated …


Some Practical Applications Of Junction Grammar In Computational Linguistics, Charles D. Bush Apr 1975

Some Practical Applications Of Junction Grammar In Computational Linguistics, Charles D. Bush

Deseret Language and Linguistic Society Symposium

No abstract provided.


Full Issue, Deseret Language And Linguistics Society Apr 1975

Full Issue, Deseret Language And Linguistics Society

Deseret Language and Linguistic Society Symposium

No abstract provided.


A Second Look At Unpassives, Joel Hust Apr 1975

A Second Look At Unpassives, Joel Hust

Deseret Language and Linguistic Society Symposium

No abstract provided.


Small Mammal Survey In Two Geographically Separated Aspen Areas, Apichart Thammaruxs Apr 1975

Small Mammal Survey In Two Geographically Separated Aspen Areas, Apichart Thammaruxs

Theses and Dissertations

Small mammal surveys were conducted in two geographically separated aspen areas, in the Chicken Creek Watershed Management Unit, Utah, and Break Neck Flat, Wyoming. Four small mammal species, Peromyscus maniculatus, Clethrionomys gapperi, Zapus princeps and Eutamias minimus were caught most often in both areas of the aspen ecosystem. Peromyscus maniculatus was usually the most abundant animal trapped at all locations indicating the success of this species in aspen communities. The proportion of each species trapped, however, fluctuated, likely in accordance with responses to periodic biotic and abiotic factors. This data will serve as baseline information for the U.S. Forest Service …


Folate Content Of Bacillus Subtilis, David Nelson Hintze Apr 1975

Folate Content Of Bacillus Subtilis, David Nelson Hintze

Theses and Dissertations

Bacillus subtilis can synthesize deoxythymidylate via either of two pathways. The working hypothesis is that the two reactions are very similar, differing only with respect to specificity for the type of folate required as substrate. The folates from B. subtilis were isolated and were determined by gel chromatography to be derivatives of pteroyltriglutamate and pteroyldiglutamate. Kav values for the two folate species are reported. Conjugase treatment revealed no other highly conjugated folates present. It was also observed that mutants deficient in one or the other of the two pathways grow at the same rate as wild-type cells under conditions allowing …


A Comparative Investigation Of Mammalian Serine Transhydroxymethylases, Sanha Panichajakul Apr 1975

A Comparative Investigation Of Mammalian Serine Transhydroxymethylases, Sanha Panichajakul

Theses and Dissertations

Serine transhydroxymethylase was purified one thousand-fold from bovine brain and one hundred and twenty-fold from bovine liver. Both enzymes were yellow due to the presence of the coenzyme pyridoxal 5'-phosphate. Polyacrylamide gel electrophoresis of the liver enzyme showed one major band containing 95% of the protein, while in the case of the brain enzyme two major bands of nearly equal intensity were observable. The specific activity of the crude liver enzyme was about sixty times higher than that of brain. The liver enzyme was also more heat stable than the brain enzyme. The purified enzymes exhibited L-allothreonine and L-threonine aldolase …


Ecology Of The Ferruginous Hawk (Buteo Regalis) In Central Utah Population Dynamics And Nest Site Selection, Neil D. Woffinden Apr 1975

Ecology Of The Ferruginous Hawk (Buteo Regalis) In Central Utah Population Dynamics And Nest Site Selection, Neil D. Woffinden

Theses and Dissertations

Research was conducted to determine the effect of prey numbers on the nesting success of the Ferruginous Hawk (Buteo regalis). Conditions associated with nest site selection were also established. Frequent visits were made to active nests to determine clutch sizes, hatching dates and fledging success. Prey remains were collected from nests and analyzed. Kilometer square transects were made throughout the study area in 1974 to determine jackrabbit densities. A drastic decline in numbers of Ferruginous Hawks occurred. The number of young fledged also declined throughout the study while nestling mortality increased. Jackrabbit numbers were high in 1972 and then declined …


A Comparative Study Of Some Population Characteristics Of Calyptraea Fastigiata Gould, Crepidula Lingulata Gould, And Crepidula Nummaria Gould (Gastropoda, Prosobranchia), Roger Harold Goodwill Apr 1975

A Comparative Study Of Some Population Characteristics Of Calyptraea Fastigiata Gould, Crepidula Lingulata Gould, And Crepidula Nummaria Gould (Gastropoda, Prosobranchia), Roger Harold Goodwill

Theses and Dissertations

A comparative study of the field populations of Crepidula lingulata, Crepidula nurnmaria, and Calyptraea fastigiata indicated all three preferred a rocky substrate but favored different size rocks. Their positions on the rocks varied but the greatest numbers were found attached to the undersides. Crepidula lingulata and C. nummaria preferred larger rocks and were found in intraspecific associations more often than C. fastigiata which preferred smaller rocks. These associations occurred with a 1:1 sex ratio; however, the overall population did not. Crepidula lingulata had a high female count and C. fastigiata a high male count. Males, of all three species, were …