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Does A Rigid Body Limit Maneuverability?, Jeffrey A. Walker Phd Oct 2000

Does A Rigid Body Limit Maneuverability?, Jeffrey A. Walker Phd

Faculty Publications

Whether a rigid body limits maneuverability depends on how maneuverability is defined. By the current definition, the minimum radius of the turn, a rigid-bodied, spotted boxfish Ostracion meleagris approaches maximum maneuverability, i.e. it can spin around with minimum turning radii near zero. The radius of the minimum space required to turn is an alternative measure of maneuverability. By this definition, O. meleagris is not very maneuverable. The observed space required by O. meleagris to turn is slightly greater than its theoretical minimum but much greater than that of highly flexible fish. Agility, the rate of turning, is related to maneuverability. …


The Aquaculture Of Non-Endemic Species In Western Australia Silver Perch (Bidyanus Bidyanus), Tina Thorne, H. G. Brayford Oct 2000

The Aquaculture Of Non-Endemic Species In Western Australia Silver Perch (Bidyanus Bidyanus), Tina Thorne, H. G. Brayford

Fisheries Management Papers

The development of commercial aquaculture of a non-endemic species such as silver perch raises a number of important issues relating to translocation. These include the potential of the introduced species to: impact on genetic diversity; introduce disease; and impact on - the natural environment; and - the biodiversity of native species. This Management Paper has been drafted in liaison with the Department of Environmental Protection in accordance with the principles of rish assessment, taking into account the above issues. It is considered that the implementation of this policy will protect the natural environment and native fish species. It will also …


Varying The Abundance Of O Antigen In Rhizobium Etli And Its Effect On Symbiosis With Phaseolus Vulgaris, K. Dale Noel, Lennart Scott Forsberg, Russell W. Carlson Oct 2000

Varying The Abundance Of O Antigen In Rhizobium Etli And Its Effect On Symbiosis With Phaseolus Vulgaris, K. Dale Noel, Lennart Scott Forsberg, Russell W. Carlson

Biological Sciences Faculty Research and Publications

Judged by migration of its lipopolysaccharide (LPS) in gel electrophoresis, the O antigen of Rhizobium etli mutant strain CE166 was apparently of normal size. However, its LPS sugar composition and staining of the LPS bands after electrophoresis indicated that the proportion of its LPS molecules that possessed O antigen was only 40% of the wild-type value. Its LPS also differed from the wild type by lacking quinovosamine (2-amino-2,6-dideoxyglucose). Both of these defects were due to a single genetic locus carrying a Tn5 insertion. The deficiency in O-antigen amount, but not the absence of quinovosamine, was suppressed by transferring into …


Is Reproduction By Tree Swallows (Tachycineta Bicolor) Cost-Free?, Michael T. Murphy Oct 2000

Is Reproduction By Tree Swallows (Tachycineta Bicolor) Cost-Free?, Michael T. Murphy

Biology Faculty Publications and Presentations

We manipulated brood sizes of Tree Swallows (Tachycineta bicolor) in 1996 and 1997 to test for the existence of intra- and intergenerational costs of reproduction. Modal clutch size was six eggs, but experimental brood sizes ranged from two to nine young. Nestling starvation was higher in 1996 (and dependent on brood size) than in 1997, but in both years enlargement of brood size resulted in increased productivity. Nestling mass near fledging was negatively correlated with brood size, but tarsus length and wing chord were not. Food deliveries by parents increased steadily between broods of two to six young but then …


Biology Department Publications: 2000, Sam Lindgren Sep 2000

Biology Department Publications: 2000, Sam Lindgren

Biology Department Bibliographies

This document is a noncomprehensive list of publications made by graduate students, post-doctoral researchers, and faculty members in the Biology Department in 2000. It indexes those publications available through major databases, and serves as an archival record of the Department’s robust scholarly contributions.


Los Anfibios Del Monumento Natural Barro Colorado, Parque Nacional Soberania Y Areas Adyacentes, Rafael O. De Sá Sep 2000

Los Anfibios Del Monumento Natural Barro Colorado, Parque Nacional Soberania Y Areas Adyacentes, Rafael O. De Sá

Biology Faculty Publications

This book focuses on the batrachofauna of Barro Colorado Nature Monument. Soberania National Park and adjacent areas. It complements other recent publications on Neotropical amphibians such as those by Rodriguez and Duellman ( 1994) on Peru, Achaval and Olmos (1995) on Uruguay, and Meyer and Foster (1996) on Belize. The goal of these books is to reach a wider audience than the more technical batrachofaunal summaries-e.g., Frogs of Boracéia (Heyer 1990). Amphibians of Argentina (Cei 1985), and Frogs of the Genus Eleutherodactylus in Western Ecuador (Lynch and Duellman 1997). These geographically focused guides are especially useful to students, amateur biologists, …


The Impact Of Lianas On Tree Regeneration In Tropical Forest Canopy Gaps: Evidence For An Alternative Pathway Of Gap‐Phase Regeneration, Stefan A. Schnitzer, James W. Dalling, Walter P. Carson Aug 2000

The Impact Of Lianas On Tree Regeneration In Tropical Forest Canopy Gaps: Evidence For An Alternative Pathway Of Gap‐Phase Regeneration, Stefan A. Schnitzer, James W. Dalling, Walter P. Carson

Biological Sciences Faculty Research and Publications

1 Regeneration in forest canopy gaps is thought to lead invariably to the rapid recruitment and growth of trees and the redevelopment of the canopy. Our observations, however, suggest that an alternate successional pathway is also likely, whereby gap‐phase regeneration is dominated by lianas and stalled in a low‐canopy state for many years. We investigated gap‐phase regeneration in an old‐growth tropical forest on Barro Colorado Island (BCI) in Panama to test the following two hypotheses: (i) many gaps follow a pathway in which they remain at a low canopy height and are dominated by lianas and (ii) the paucity of …


Physiology Of A Microgravity Environment Invited Review: Microgravity And Skeletal Muscle, Robert H. Fitts, Danny R. Riley, Jeffrey J. Widrick Aug 2000

Physiology Of A Microgravity Environment Invited Review: Microgravity And Skeletal Muscle, Robert H. Fitts, Danny R. Riley, Jeffrey J. Widrick

Biological Sciences Faculty Research and Publications

Spaceflight (SF) has been shown to cause skeletal muscle atrophy; a loss in force and power; and, in the first few weeks, a preferential atrophy of extensors over flexors. The atrophy primarily results from a reduced protein synthesis that is likely triggered by the removal of the antigravity load. Contractile proteins are lost out of proportion to other cellular proteins, and the actin thin filament is lost disproportionately to the myosin thick filament. The decline in contractile protein explains the decrease in force per cross-sectional area, whereas the thin-filament loss may explain the observed postflight increase in the maximal velocity …


Physiology Of A Microgravity Environment Invited Review: Microgravity And Skeletal Muscle, Robert H. Fitts, Danny R. Riley, Jeffrey J. Widrick Aug 2000

Physiology Of A Microgravity Environment Invited Review: Microgravity And Skeletal Muscle, Robert H. Fitts, Danny R. Riley, Jeffrey J. Widrick

Biological Sciences Faculty Research and Publications

Spaceflight (SF) has been shown to cause skeletal muscle atrophy; a loss in force and power; and, in the first few weeks, a preferential atrophy of extensors over flexors. The atrophy primarily results from a reduced protein synthesis that is likely triggered by the removal of the antigravity load. Contractile proteins are lost out of proportion to other cellular proteins, and the actin thin filament is lost disproportionately to the myosin thick filament. The decline in contractile protein explains the decrease in force per cross-sectional area, whereas the thin-filament loss may explain the observed postflight increase in the maximal velocity …


Early Instar Growth And Survivorship In The Common Baskettail Dragonfly Epitheca Cynosura (Anisoptera: Corduliidae)., Bryan Arthur Reece Aug 2000

Early Instar Growth And Survivorship In The Common Baskettail Dragonfly Epitheca Cynosura (Anisoptera: Corduliidae)., Bryan Arthur Reece

Electronic Theses and Dissertations

Egg masses of Epitheca cynosura were collected from Bays Mountain Park, Tennessee, USA, in June, 1999. Newly hatched individuals were placed into enclosures and sampled at scheduled time intervals throughout the summer. Enclosures were exposed to combinations of high and low densities and presence/absence of a second-year class E. cynosura predator. Survivorship, mean head widths, and mean dry masses were compared across treatments. Due to poor recovery of early-instar larvae, survivorship showed no significant differences in mortality among treatments. The predator present treatment caused significantly smaller head widths and dry masses only on days 42 and 55. The density treatment …


Kentucky Salamanders Of The Genus Desmognathus: Their Identification, Distribution, And Morphometric Variation, Leslie Scott Meade Jul 2000

Kentucky Salamanders Of The Genus Desmognathus: Their Identification, Distribution, And Morphometric Variation, Leslie Scott Meade

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Leslie Scott Meade on July 24, 2000.


Molecular Aspect Of Leaf Senescence, Edward Himelblau, Betania Quirino, Yoo-Sun Noh, Richard Amasino Jul 2000

Molecular Aspect Of Leaf Senescence, Edward Himelblau, Betania Quirino, Yoo-Sun Noh, Richard Amasino

Biological Sciences

Senescence is the last stage of leaf development and one type of programmed cell death that occurs in plants. The relationships among senescence programs that are induced by a variety of factors have been addressed at a molecular level in recent studies. Furthermore, an overlap between the pathogen-response and senescence programs is beginning to be characterized. The complexity of the senescence program is also evident in studies of senescence-specific gene regulation and the role of photosynthesis and plant hormones in senescence regulation. New molecular-genetic approaches are expected to be useful in unraveling the molecular mechanisms of the leaf senescence program.


Sequence Analysis Of Bacterial Dna In The Colon And Stomach Of The Tyrolean Iceman, Raul J. Cano, Friedrich Tiefenbrunner, Massimo Ubaldi, Clarissa Del Cueto, Stefania Luciani, Tobe Cox, Paula Orkand, Karl H. Kunzel, Franco Rollo Jul 2000

Sequence Analysis Of Bacterial Dna In The Colon And Stomach Of The Tyrolean Iceman, Raul J. Cano, Friedrich Tiefenbrunner, Massimo Ubaldi, Clarissa Del Cueto, Stefania Luciani, Tobe Cox, Paula Orkand, Karl H. Kunzel, Franco Rollo

Biological Sciences

The male human body found in an Alpine glacier on September 19, 1991 ("Tyrolean Iceman") has, for the first time in history, given scientists a chance to perform detailed anatomical, histological, and molecular investigations on the organs of a person from the Neolithic Age (5350-5100 B.P.). In the present study, tissue samples aseptically taken from the stomach and the colon of the mummy were utilized for DNA extraction, and the DNA was PCR-amplified, using primer pairs designed to bind to fragments of the 16s ribosomal RNA gene (16s rDNA) of a broad range of bacteria. The PCR products were cloned …


Energetics Of Larval Swimming And Metamorphosis In Four Species Of Bugula (Bryozoa), Dean E. Wendt Jun 2000

Energetics Of Larval Swimming And Metamorphosis In Four Species Of Bugula (Bryozoa), Dean E. Wendt

Biological Sciences

The amount of energy available to larvae during swimming, location of a suitable recruitment site, and metamorphosis influences the length of time they can spend in the plankton. Energetic parameters such as swimming speed, oxygen consumption during swimming and metamorphosis, and elemental carbon and nitrogen content were measured for larvae of four species of bryozoans, Bugula neritina, B. simplex, B. stolonifera, and B. turrita. The larvae of these species are aplanktotrophic with a short free-swimming phase ranging from less than one hour to a maximum of about 36 hours. There is about a fivefold difference in larval volume …


Delivering Copper Within Plant Cells, Edward Himelblau, Richard M. Amasino Jun 2000

Delivering Copper Within Plant Cells, Edward Himelblau, Richard M. Amasino

Biological Sciences

Two genes recently identified in Arabidopsis thaliana may be involved in sequestering free copper ions in the cytoplasm and delivering copper to post-Golgi vesicles. The genes COPPER CHAPERONE and RESPONSIVE TO ANTAGONIST1 are homologous to copper-trafficking genes from yeast and humans. This plant copper-delivery pathway is required to create functional ethylene receptors. The pathway may also facilitate the transport of copper from senescing leaf tissue. In addition, several other genes have been identified recently that may have a role in copper salvage during senescence.


The Mayfly Newsletter, Peter M. Grant Jun 2000

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.


Reflections On Scientific And Religious Metaphor, Ursula Goodenough Jun 2000

Reflections On Scientific And Religious Metaphor, Ursula Goodenough

Biology Faculty Research

The importance of scientific conflicts for theology and philosophy is difficult to judge. In many disputes of significance, prominent scientists can be found on both sides. Profound philosophical and religious implications are sometimes said to be implied by the new theory as well. This article examines the dispute over natural selection between Richard Dawkins and Stephen Jay Gould as a contemporary instance of such a conflict. While both claim that profound philosophical conclusions flow from their own alternative account of evolution, I suggest that the implication is not as great as is claimed and that the alleged implications have as …


Protozoan Free Colonies Of Lepidoptera, Kingston L. H. Leong May 2000

Protozoan Free Colonies Of Lepidoptera, Kingston L. H. Leong

Biological Sciences

A method for the establishment and maintenance of colonies of Lepidoptera which are free of contamination with protozoa is provided. The colonies consists of individuals capable of breeding and producing viable, noncontaminated butterflies.


Sickle Cell Disease: Animal Models And Gene Therapy, Francesca M. Mellion May 2000

Sickle Cell Disease: Animal Models And Gene Therapy, Francesca M. Mellion

Electronic Dissertations and Theses

Sickle cell disease is a worldwide health problem in countries ranging from its origin, Africa, to the United States of America. The understanding of sickle cell disease dates to Zimbabwe in the 1940's. Sickle cell trait is the term used to describe healthy unaffected carriers (heterozygous) of the genetic condition known as Sickle Cell Disease. It is estimated that there are about 100,000 genes in the human body and each of them codes for a different trait. About 5,000 of these genes are known to carry mutations serious enough to cause genetic diseases. This research deal with sickle cell mice …


Effects Of Forced Weaning On Mother-Daughter Associations And Reproduction In Bison (Bos Bison), Jennifer S. Brookshier May 2000

Effects Of Forced Weaning On Mother-Daughter Associations And Reproduction In Bison (Bos Bison), Jennifer S. Brookshier

Biology

While the social organization of ungulates has received much attention, the nature and extent of the mother-daughter association is still not fully known for some species. In bison, mothers and daughters have a long-term association that may extend beyond the age of weaning. This association is believed to facilitate the daughters' social integration into the herd. I compared the mother-daughter association for 29 yearling females that were forcibly weaned from their mothers to that of 19 yearling females that were naturally weaned. Forcibly weaned yearlings did not reassociate with their mothers following winter separation, while naturally weaned yearlings associated with …


Sexual Dichromatism In Bohemian Waxwings, James Brian Burns May 2000

Sexual Dichromatism In Bohemian Waxwings, James Brian Burns

Biology

If a species of birds is monomorphic, how do individuals identify members of the opposite sex? Birds may use cues in the ultraviolet wavelengths (350-400 nm), which are invisible to humans. This thesis presents evidence of sexual dichromatism in Bohemian Waxwings (Bombycilla garrulus). The strongest differences occurred in the tail coverts, the yellow tail tips, and the red waxy tips of the secondaries. Like other birds, waxwings derive colors from diet-based pigments and from synthesized colors. Because these color types differ in origin, each could provide different visual information about a bird's condition. This led to the testing …


Effects Of Carbohydrate Foods On Foraging Decisions Of The Parasitoid Bathyplectes Curculionis (Thomson) (Hymenoptera: Ichneumonidae), Helen Spafford Jacob May 2000

Effects Of Carbohydrate Foods On Foraging Decisions Of The Parasitoid Bathyplectes Curculionis (Thomson) (Hymenoptera: Ichneumonidae), Helen Spafford Jacob

Biology

In a series of field and laboratory experiments, I explored the trade-off between self-maintenance and current reproduction for the parasitoid Bathyplectes curculionis (Thomson)(Hymenoptera: Ichneumonidae), an economically important natural enemy of the alfalfa weevil, the most significant pest in forage alfalfa. Floral nectars, pea aphid honeydew, and artificial foods such as sugar sprays are likely to assist B. curculionis in meeting its self-maintenance needs. Once these needs are met then B. curculionis females may be more likely to search for hosts to parasitize. However, these foods must not only be available, but accessible, of high quality, and detectable, to be of …


The Utilization Of Steep Slopes By Desert Tortoises (Gopherus Agassizii) In The Western Mojave Desert, Ty J. Gardner May 2000

The Utilization Of Steep Slopes By Desert Tortoises (Gopherus Agassizii) In The Western Mojave Desert, Ty J. Gardner

Biology

Desert tortoises (Gopherus agassizii) were located on steep slopes at three sites in the western Mojave Desert. These sites were located at: 1) the rifle range of the Marine Corps Logistics Base, Barstow, California, 2) the southern boundary of the Fort Irwin National Training Center, California, immediately west of Manix Tank Trail, and 3) the Lava Range of the Marine Corps Air Ground Combat Center, Twentynine Palms, California. Additionally, a valley site at the Sand Hill range of the Marine Corps Air Ground Combat Center, Twentynine Palms, California, was included for comparison. Study tortoises were found on slopes …


Snfa, The Dictyostelium Discoideum Snf1/Ampk Protein Kinase, Sandy Sung May 2000

Snfa, The Dictyostelium Discoideum Snf1/Ampk Protein Kinase, Sandy Sung

Biology

SNF1/AMPK protein kinases are a conserved group of eukaryotic serine/threonine protein kinases that mediate a variety of stress responses, including the response to nutrient deprivation. This report describes the isolation of snfA, the Dictyostelium discoideum SNF1/AMPK ortholog, and an examination of snfA protein function. snfA is a single copy gene that encodes a predicted 80.5 kD polypeptide. A single 2.8 kb snfA transcript was present at nearly constant levels during vegetative growth and all stages of development. The predicted snfA protein consists of three domains: an amino terminal kinase domain that is highly conserved in other SNF1/AMPK protein kinases, …


Fisheries Research Report No. 119 - Final Report, Frdc Project 95/037: The Biology And Stock Assessment Of The Tropical Sardine, Sardinella Lemuru, Off The Mid-West Coast Of Western Australia, Daniel J. Gaughan, Ronald W. Mitchell May 2000

Fisheries Research Report No. 119 - Final Report, Frdc Project 95/037: The Biology And Stock Assessment Of The Tropical Sardine, Sardinella Lemuru, Off The Mid-West Coast Of Western Australia, Daniel J. Gaughan, Ronald W. Mitchell

Fisheries Research Reports

Exploratory fishing for the tropical sardine, Sardinella lemuru, offshore of Geraldton on the midwest coast of Western Australia in the early 1990s, led to the establishment of a developmental purse seine fishery in this region. This fishery showed potential for substantial expansion, but as there was no information on S. lemuru in WA there was a need to undertake research during the developmental period. The biology and fishery for S. lemuru in WA were therefore investigated over a three year period between July 1995 and June 1998 with the aim of providing stock assessment advice.

The biology of S. lemuru …


Fisheries Research Report No. 121 - Synopsis Of The Biology And Exploitation Of The Blue Swimmer Crab, Portunus Pelagicus Linnaeus, In Western Australia, Mervi I. Kangas May 2000

Fisheries Research Report No. 121 - Synopsis Of The Biology And Exploitation Of The Blue Swimmer Crab, Portunus Pelagicus Linnaeus, In Western Australia, Mervi I. Kangas

Fisheries Research Reports

This report summarises the existing studies which have provided information on the biology, population characteristics and exploitation of the blue swimmer crab, Portunus pelagicus, in Western Australia. Gaps in the existing knowledge are also highlighted to assist in targeting new research initiatives. Portunus pelagicus matures at about one year and in temperate regions females mate only once a year. This is because mature crabs moult only once a year. It appears from studies to date that Western Australian crabs are one genetic population. This is being further investigated. Migration of the blue swimmer crab occurs between estuaries and the ocean …


The Impacts Of A Nonindigenous Marine Predator In A California Bay, Edwin D. Grosholz, Gregory M. Ruiz, Cheryl A. Dean, Kim A. Shirley, John L. Maron, Peter G. Connors May 2000

The Impacts Of A Nonindigenous Marine Predator In A California Bay, Edwin D. Grosholz, Gregory M. Ruiz, Cheryl A. Dean, Kim A. Shirley, John L. Maron, Peter G. Connors

Biological Sciences Faculty Publications

Coastal marine ecosystems worldwide are being altered rapidly by the invasion of nonindigenous species. Unlike terrestrial and freshwater systems, the impacts of an invading species have never been quantified on multiple trophic levels for a marine food web. We measured the impact of the nonindigenous green crab, Carcinus maenas, on a coastal marine food web in central California and found that this predator exerted strong “top-down” control, significantly reducing the abundances of several of the 20 invertebrate species monitored over a 9-yr period. Densities of native clams, Nutricola tantilla and Nutricola confusa, and native shore crabs, Hemigrapsus oregonensis, showed 5-fold …


Integrating Development With Evolution: A Case Study With Beetle Horns, Douglas J. Emlen May 2000

Integrating Development With Evolution: A Case Study With Beetle Horns, Douglas J. Emlen

Biological Sciences Faculty Publications

No abstract provided.


Aspects Of Insect Conservation: Community Effects Of Habitat Patch Edge, Area, And Shape, Sharon L. Osowski May 2000

Aspects Of Insect Conservation: Community Effects Of Habitat Patch Edge, Area, And Shape, Sharon L. Osowski

Biology

The findings of this study have implications for such conservation issues such as habitat fragmentation, reserve planning, and habitat conservation and ecosystem management. This study attempted to answer questions, using an empirical study, on aspects of habitat fragmentation. Current theory about reserve design suggests that: 1) larger areas have higher diversity/abundance than smaller areas; 2) square patches have higher diversity/abundance than linear patches; and 3) patches with hospitable matrices have higher diversity/abundance than inhospitable matrices. This study also adds to the knowledge regarding invertebrate responses to fragmentation. The experimental design was a split-plot multifactorial study. The edge factor had three …


Molecular And Morphological Identification Of An Endophytic Fusarium Isolated From Wheat And Characterization Of Its Laccases In Comparison To Affiliated Fusarium Isolates, Sun Il Kwon May 2000

Molecular And Morphological Identification Of An Endophytic Fusarium Isolated From Wheat And Characterization Of Its Laccases In Comparison To Affiliated Fusarium Isolates, Sun Il Kwon

Biology

A fungal isolate present as a seed endophyte caused disease in wheat and other cereals when grown under stressed conditions. The isolate was identified as a member of the Asian clade of the Gibberella fujikuroi species complex in the genus Fusarium, members of which are known as plant pathogens and producers of mycotoxins. The closest relative to the fungus was Fusarium proliferatum, although none of the previously described species was identical in all morphological and molecular phylogenetic characters. At least six laccase isozymes were detected in mycelial extracts or from extracellular culture filtrates of the Fusarium-wheat isolate. …