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Evolutionary Change In A Receiver Bias: A Comparison Of Female Preference Functions, Alexandra Basolo Jan 1998

Evolutionary Change In A Receiver Bias: A Comparison Of Female Preference Functions, Alexandra Basolo

School of Biological Sciences: Faculty Publications

Female poeciliid fishes of the sister genera Xiphophorus and Priapella share a preference for males with swords, despite phylogenetic information suggesting that swords arose in Xiphophorus after the divergence of the two genera. This study examines the strength of sword and body-size preferences in a representative of both genera. A comparison of the preference functions reveals that the strength of the preference favoring a sword in P. olmecae is significantly stronger than that in X. helleri. This result demonstrates that the pre-existing bias is not evolutionarily fixed, and that there has been change in the bias favoring the sword, …


Trace Element Signatures In Otoliths Record Natal River Of Juvenile American Shad (Alosa Sapidissima), Simon R. Thorrold, Cynthia M. Jones, Steven E. Campana, James W. Mclaren, Joseph W. H. Lam Jan 1998

Trace Element Signatures In Otoliths Record Natal River Of Juvenile American Shad (Alosa Sapidissima), Simon R. Thorrold, Cynthia M. Jones, Steven E. Campana, James W. Mclaren, Joseph W. H. Lam

OES Faculty Publications

The elemental composition of fish otoliths may represent a permanent record of the environmental conditions an individual has experienced as trace elements, incorporated into the growing surface of the otolith, reflect the physical and chemical characteristics of the ambient water. We tested the utility of trace element signatures in otoliths as natural tags of the river of origin of juvenile American shad (Alosa sapidissima) collected from the Connecticut, Hudson and Delaware Rivers in August and October 1994. Four elements (K, Mn, Sr, and Ba) showed significant variability among sites within rivers in August, although only Mg showed a …


The Magnitude Of Site And Time Interaction Effect In Tsetse Fly (Diptera: Glossinidae) Trap Catches, A. Odulaja, S. Mihok, I. M. Abu-Zinid Jan 1998

The Magnitude Of Site And Time Interaction Effect In Tsetse Fly (Diptera: Glossinidae) Trap Catches, A. Odulaja, S. Mihok, I. M. Abu-Zinid

All Peer-Reviewed Publications

Site and time effects are important factors determining trap catches of tsetse flies. These factors may interact significantly and therefore confound interpretation of time series data used for population monitoring. We therefore investigated the magnitude and importance of site x time interactions in trap catches of Glossina pallidipes Austen and G. longipennis Corti using a 2200 trap-days (400 trap-months) data set. The interaction was found to be significant (P < 0.05) in 46-100% of the combinations of different numbers of months and sites between 2 and 12. The mean percent variance due to the interaction ranged between 4% and 28% for G. pallidipes and 12% and 36% for G. longipennis. The interaction was usually less important than the effect of site alone but more important than the effect of time alone. These results suggest that tsetse researchers should examine critically the adequacy of existing approaches to population monitoring with traps and to testing new traps and odour baits.


Olfactory Responses Of Glossina Fuscipes Fuscipes (Diptera: Glossinidae) To The Monitor Lizard Varanus Niloticus Niloticus, M. M. Mohamed-Ahmed Jan 1998

Olfactory Responses Of Glossina Fuscipes Fuscipes (Diptera: Glossinidae) To The Monitor Lizard Varanus Niloticus Niloticus, M. M. Mohamed-Ahmed

All Peer-Reviewed Publications

Visual and olfactory responses of Glossina fuscipes fuscipes Newstead to the monitor lizard, Varanus niloticus niloticus Laurenti were studied using various catching devices near Lake Victoria, Kenya. Electric nets baited with visible lizards caught more males (x2.1) and significantly more females (x2.0) than unbaited nets. Lizards concealed in electrified black Pvc pipe models, simulating the shape and size of a monitor lizard, increased significantly the catches of tsetse by 2.1 times. Fresh lizard urine dispensed at an evaporation rate of 500 to 1000 mg/h also increased significantly the catches of flies at biconical traps, electrified models and electric nets. Identification …


Locational Factors Determining The Distribution Of Nesting Sites For A Colony Of Wedge-Tailed Shearwaters, Puffinus Pacificus, On West Wallabi Island, Houtman Abrolhos, Western Australia, Julie Davis Jan 1998

Locational Factors Determining The Distribution Of Nesting Sites For A Colony Of Wedge-Tailed Shearwaters, Puffinus Pacificus, On West Wallabi Island, Houtman Abrolhos, Western Australia, Julie Davis

Theses : Honours

West Wallabi Island in the Houtman Abrolhos, Western Australia, provides significant breeding habitat for the largest colony of Wedge-tailed Shearwaters, Puffinus pacificus, in the Eastern Indian Ocean. The Department of Conservation and Land Management (CALM) surveyed the Island in 1992 and estimated the population to be in excess of 1,117,000 pairs of breeding birds. Recent proposals to open the Abrolhos area to a larger number of visitors has identified the need for more detailed investigations into the relationship of birds and habitat. An understanding of this relationship provides a means of determining the ways in which populations will respond to …


The Birds And Habitat Of Kings Park, Bradley W. Cox Jan 1998

The Birds And Habitat Of Kings Park, Bradley W. Cox

Theses : Honours

Kings Park is a large urban park in the centre of Perth with extensive areas of semi-natural bushland. The park is an important refuge for birds in the metropolitan area but is losing species through habitat disturbance. Understanding the way in which birds are related to their habitat helps to understand the effect of habitat disturbance on the bird community. The aim of this project was to generate guidelines which will aid in the management and conservation of birds in the park, through an understanding of the relationship of the birds to their habitat. The avifauna and various habitat factors …


Core Conservation Biology Monographs: A Citation Analysis, Chad E. Buckley Oct 1997

Core Conservation Biology Monographs: A Citation Analysis, Chad E. Buckley

Faculty and Staff Publications – Milner Library

Conservation biology is a multidisciplinary subject of recent origins. Analysis of cited monographs from the journal Conservation Biology resulted in a list of 47 monographs which were heavily cited for this discipline. Over half of these were from related disciplines such as ecology, genetics, evolution, population biology, statistics, and natural resource management.


Diet Of A Relict Population Of The Eastern Woodrat In Nebraska, Hugh H. Genoways, Patricia W. Freeman, Mary K. Clausen Sep 1997

Diet Of A Relict Population Of The Eastern Woodrat In Nebraska, Hugh H. Genoways, Patricia W. Freeman, Mary K. Clausen

University of Nebraska State Museum: Mammalogy Papers

The relict population of Neotoma floridana occurring along the Niobrara River in north-central Nebraska was found to have a diet composed of 38 types of food items of which 37 types were plants. Unique features of the summer diet of this population were a higher than expected use of red cedar (Juniperus virginiana) and invertebrates as food items.


Detection Of Hybridization Events Between The Coyote, Canis Latrans, And The Domestic Dog, Canis Familiaris, Using Two Polymorphic Microsatellite Loci And Cranial Morphometric Analysis, John Jobe Cox Aug 1997

Detection Of Hybridization Events Between The Coyote, Canis Latrans, And The Domestic Dog, Canis Familiaris, Using Two Polymorphic Microsatellite Loci And Cranial Morphometric Analysis, John Jobe Cox

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 John Jobe Cox on August 26, 1997.


Two New Species Of Litomosoides (Nemata: Onchocercidae) From Ctenomys Opimus (Rodentia: Ctenomyidae) On The Altiplano Of Bolivia, Sara V. Brant, Scott Lyell Gardner Aug 1997

Two New Species Of Litomosoides (Nemata: Onchocercidae) From Ctenomys Opimus (Rodentia: Ctenomyidae) On The Altiplano Of Bolivia, Sara V. Brant, Scott Lyell Gardner

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Two filarioid nematodes, Litomosoides andersoni n. sp. and Litomosoides ctenomyos n. sp. (Nemata: Onchocercidae), are described from the mesenteries of the subterranean rodent Ctenomys opimus (Rodentia: Hystrichognathi) collected on the altiplano of Bolivia. Specimens collected near Rancho Huancaroma (Oruro Dept.) in 1984 and 1986 can be recognized as undescribed by the structures of the spicules and stoma and the shape of the ovijector. This record represents the first time members of the genus Litomosoides have been recovered from rodents of the family Ctenomyidae; this also represents the first published report of these nematodes from mammals in Bolivia.


Proceedings Of The Global Conference On Ergot Of Sorghum, Carlos R. Casela, Jeffery A. Dahlberg Jun 1997

Proceedings Of The Global Conference On Ergot Of Sorghum, Carlos R. Casela, Jeffery A. Dahlberg

INTSORMIL Impacts and Bulletins

In June 1996, several of us had the opportunity to see sorghum ergot in Brazil and the damage that the disease can do. We saw severe damage in seed production plots and witnessed the pain that seed producers had to go through to deal with this new problem. There was a wide spread scare in the sorghum community in the Americas because of the infamous reputation of the disease in causing damage in seed production fields. As a silver lining, we also observed first hand, the excellent research program that the Brazilians had in place. It became apparent that all …


The Effects Of Hydrilla Infestation On Selected Wintering Waterfowl: Santee Copper Lake System, South Carolina, William Davis May 1997

The Effects Of Hydrilla Infestation On Selected Wintering Waterfowl: Santee Copper Lake System, South Carolina, William Davis

Masters Theses & Specialist Projects

Hydrilla is an exotic aquatic weed that was introduced into Florida in the 1950's. Since that time it has spread rapidly from lake to lake throughout the southeast and beyond. The Santee Cooper lake system in eastern South Carolina was infested with the weed in the early 1980's. Since that time lake managers have sought ways to eliminate the aquatic plant and have succeeded to a great extent through the use of sterile grass carp as a biological control agent. This paper, however, contains evidence to support the view that hydrilla is actually a beneficial habitat for many species on …


Evaluation Of Continuous Flow Constructed Wetlands Treating Swine Waste, Stephanie Rivard May 1997

Evaluation Of Continuous Flow Constructed Wetlands Treating Swine Waste, Stephanie Rivard

Masters Theses & Specialist Projects

The ability for wetlands to purify contaminated water is not a new concept. Natural wetlands have been cleansing water within our environment for ages. After studying the process of natural wetlands the same concept was applied to municipal waste. It is the success of constructed wetlands treating municipal waste that created the new idea for the application of a wetland system to treat wastewater from livestock facilities. Through proper design and management, constructed wetlands may be useful for reducing the nutrient concentration of waste (Rieck el al., 1996). Taking into consideration the higher nutrient loads of livestock waste, the same …


Wetland Delineation Of Camp Ripley In Minnesota, Richard A. Spencer May 1997

Wetland Delineation Of Camp Ripley In Minnesota, Richard A. Spencer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Department of Defense (DoD) maintains approximately 25 million acres of land that is used for military training in the continental United States. Currently, federal and state laws and regulations require that the DoD land be managed so that any activity, including training, will have a minimal effect on the natural environment.


Delineation Of Ecological Units For The Ashley National Forest, At The Landscape Level, Using Classification Tree Modeling, Teresa H. Swiatek May 1997

Delineation Of Ecological Units For The Ashley National Forest, At The Landscape Level, Using Classification Tree Modeling, Teresa H. Swiatek

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study integrated remotely sensed data, geographic information system (GIS), and classification tree-based modeling to delineate ecological units for the Ashley National Forest. Data points, provided by the Ashley National Forest, with a known location and dominant vegetation type, were related to data layers that were determined to be helpful in a landtype classification. These layers included elevation, slope, aspect, potential solar irradiation, precipitation, geology, basins, Landsat thematic mapper (TM) bands 3, 4, 5, and 6, and basic land cover. These points, with their related information, were then used to train the tree-based model for landtype classification. This resulted in …


Natural Variability Of Vegetation, Soils, And Physiography In The Bristlecone Pine Forest Of The Rocky Mountains, Brigitte M. Ranne, William L. Baker, Tom Andrews, Michael G. Ryan Mar 1997

Natural Variability Of Vegetation, Soils, And Physiography In The Bristlecone Pine Forest Of The Rocky Mountains, Brigitte M. Ranne, William L. Baker, Tom Andrews, Michael G. Ryan

Great Basin Naturalist

Pinus aristata Engelm. forest vegetation in Colorado was studied to determine vegetation composition and the relationship between vegetation and environment. Species percent cover, tree size class, and environmental variables were recorded for 49 plots. Previously collected data for 4 plots from New Mexico were included. Environmental variables included latitude, longitude, elevation, slope, aspect, topographic position, parent material, percent rock cover, mean rock size, litter depth, estimated plot age class, and evidence of anthropogenic disturbance. Soils were analyzed for texture, depth, and percent carbon and nitrogen. Pinus aristata foliage was analyzed for percent nitrogen and phosphorus. Direct and indirect gradient analyses …


Camptotheca Lowreyana, A New Species Of Anti-Cancer Happytrees, Shiyou Li Jan 1997

Camptotheca Lowreyana, A New Species Of Anti-Cancer Happytrees, Shiyou Li

NCPC Publications and Patents

Camptotheca Decaisne (happytrees or Xi Shu, Nyssaceae) is a .monotypic genus endemic to China. Its single species C. acuminata Decaisne ( 1873) has been the major source of Camptothecins, the promising anti - cancer and potential anti - viral drugs (Li and Adair 1994) .

The phenotypic analysis of the genus showed that (1) C. yunnanensis Dode (1908) should be treated as a species separated from C. acuminata (see Li, n. d.) and (2) a new species as the third species of the genus should be established. The present paper describes the new species as C. lowreyana. C. lowreyana has …


Species Pools Of Seed Plants In Eastern Asia And North America, Shiyou Li, Kent T. Adair Jan 1997

Species Pools Of Seed Plants In Eastern Asia And North America, Shiyou Li, Kent T. Adair

eBooks

"In their monograph, Species Pools of seed plants in Eastern Asia and North America, Drs. Li and Adair present a comprehensive analysis of data collected during a ten-year study involving 10,000 plant species in east Asia and North America."


Contributed Papers Jan 1997

Contributed Papers

Journal of the Minnesota Academy of Science

No abstract provided.


Exploring Alternative Systems Of Classification, Kathleen A. Kron Jan 1997

Exploring Alternative Systems Of Classification, Kathleen A. Kron

Aliso: A Journal of Systematic and Floristic Botany

Classification involves the development of a system of naming clades that can represent evolutionary relationships accurately and concisely. Using the acid-loving heath plants (Ericales) as an example, one can explore the application of different classification methods. The Linnean system of naming retains the traditional hierarchical framework (named ranks) and allows for the application of many cuqently used names. The "phylogenetic systematic" approach recommends the removal of an absolute hierarchy but allows retention of traditionally used endings such as -aceae. Historical usage of these names can lead to confusion when the names are used within a discussion or text, especially when …


Assessing The Cost Of Best Management Practices In Arkansas, Richard A. Kluender, Robert C. Weih Jr., M. Corrigan, J. Pickett Jan 1997

Assessing The Cost Of Best Management Practices In Arkansas, Richard A. Kluender, Robert C. Weih Jr., M. Corrigan, J. Pickett

Journal of the Arkansas Academy of Science

A geographic information system (GIS) is a set of powerful, computer-based, analytical algorithms for solving spatial data problems. Recently, due to increases in memory size, computing speed, and programming advances, personal computers have been used in spatial analysis problems. This study reports the benefits of using a PC-based GIS system to solve a common, but complicated problem in forest management: assignment of harvesting areas with harvesting exclusion zones. Two stands each from the USDA Crossett Experimental Forest, the University of Arkansas Forest, and the Ouachita National Forest (total six) were analyzed to determine the changes due to following best management …


An Analysis Of The Variation Within Cratoxylum Arborescens (Clusiaceae) In Malesia, A.C. Church, P.F. Stevens Jan 1997

An Analysis Of The Variation Within Cratoxylum Arborescens (Clusiaceae) In Malesia, A.C. Church, P.F. Stevens

Biology Department Faculty Works

The variation within the widespread West Malesian species Cratoxylum arborescens (Vahl) Blume was analyzed and three distinctive variants were found. These are recognized formally as varieties, var. arborescens, var. miquelii King, and var. borneense A.C. Church & P.F. Stevens. A key and full descriptions are given. The characters employed to delimit the three taxa are discussed and the selection of varietal rank is justified.


Classification: More Than Just Branching Patterns Of Evolution, Tod F. Stuessy Jan 1997

Classification: More Than Just Branching Patterns Of Evolution, Tod F. Stuessy

Aliso: A Journal of Systematic and Floristic Botany

The past 35 years in biological systematics have been a time of remarkable philosophical and methodological developments. For nearly a century after Darwin's Origin of Species, systematists worked to understand the diversity of nature based on evolutionary relationships. Numerous concepts were presented and elaborated upon, such as homology, parallelism, divergence, primitiveness and advancedness, cladogenesis and anagenesis. Classifications were based solidly on phylogenetic concepts; they were avowedly monophyletic. Phenetics emphasized the immense challenges represented by phylogeny reconstruction and advised against basing classifications upon it. Pheneticists forced reevaluation of all previous classificatory efforts, and objectivity and repeatability in both grouping and …


Distribution And Abundance Of Prairie Plant Species In The Loess Hills, Thomas R. Rosburg Jan 1997

Distribution And Abundance Of Prairie Plant Species In The Loess Hills, Thomas R. Rosburg

Journal of the Iowa Academy of Science: JIAS

The species composition of grassland and ecotonal communities throughout the Loess Hills was studies between 1990 and 1993. Information pertaining to the latitudinal distribution of species in the Loess Hills, the abundance of species among community types (i.e., habitats), species persistence under woody encroachment, species associations, and resource partitioning among species is provided for the majority of grassland species occurring in the Loess Hills. The most abundant species on extant prairie in the Loess Hills include Bouteloua curtipendula (side-oats grama), Schizachyrium scoparium (little bluestem), Andropogon gerardii (big bluestem), Cornus drummondii (rough-leaved dogwood), Aster ericoides (heath aster), Carex heliophila (sun-loving sedge), …


Richard W. Pohl: Distinguished Botanist, Marjorie Conley Pohl Jan 1997

Richard W. Pohl: Distinguished Botanist, Marjorie Conley Pohl

Journal of the Iowa Academy of Science: JIAS

In her biographical portrait of Dr. Richard W. Pohl, Mrs. Pohl provides an engaging personal perspective of her late husband, his development as a botanist, his career, and his family life. We gain a sense of Dr. Pohl as a dedicated scientist as well as a humanist. Although Dr. Pohl possessed an abiding curiosity regarding all things natural, he is best known and remembered for his focus on grasses. As Mrs. Pohl documents, this interest in grasses began in the late 1930's and continued throughout his life-ultimately he was regarded as an authority on grass taxonomy both nationally and internationally. …


Dbs-Based Education And The Role Of The Teacher, James Emal, Antonio Ruiz, Miriam J. Masullo Jan 1997

Dbs-Based Education And The Role Of The Teacher, James Emal, Antonio Ruiz, Miriam J. Masullo

University of Nebraska-Lincoln Extension: Historical Materials

This paper describes how a broadcast education infrastructure can be used to access a digital library of K-12 content. Technical references to prior research and development done in support of this concept are provided. The main goal of this paper is to relate those concepts and technical developments to a solution that emphasizes the role of the teacher. The framework for this solution, EduPort/DBS, attempts to bring tools and technical options to bear on a system for education infrastructure.


Diel Activity Patterns And Host Preferences Of Glossina Fuscipes Fuscipes (Diptera: Glossinidae) Along The Shores Of Lake Victoria, Kenya, M. M. Mohamed-Ahmed, A. Odulaja Jan 1997

Diel Activity Patterns And Host Preferences Of Glossina Fuscipes Fuscipes (Diptera: Glossinidae) Along The Shores Of Lake Victoria, Kenya, M. M. Mohamed-Ahmed, A. Odulaja

All Peer-Reviewed Publications

Diurnal activity patterns and host preference of Glossina fuscipes fuscipes Newstead were studied in forest and linear habitats along Lake Victoria shore, Kenya. The objective was to identify the preferred hosts of G. f. fuscipes, the emanations of which may be attractive to this species. Hourly catches of flies in biconical traps were related to changes in the weather and the prevalence of hosts in the vicinity of traps. Flies were mainly active between 0800 and 1600 h, with males peaking around 1100 h and females around 1300 h. Activity of flies correlated directly with light intensity and temperature, but …


Changes Over Twelve Years In Populations Of Glossina Pallidipes And Glossina Longipennis (Diptera: Glossinidae) Subject To Varying Trapping Pressure At Nguruman, South-West Kenya, R. Brightwell, R. D. Dransfield, P. Stevenson, B. Williams Jan 1997

Changes Over Twelve Years In Populations Of Glossina Pallidipes And Glossina Longipennis (Diptera: Glossinidae) Subject To Varying Trapping Pressure At Nguruman, South-West Kenya, R. Brightwell, R. D. Dransfield, P. Stevenson, B. Williams

All Peer-Reviewed Publications

Long term changes in the size of populations of the tsetse Glossina pallidipes Austen and G. longipennis Corti Were monitored over a 12 year period at Nguruman in south-western Kenya. Tsetse populations were subject to droughts of varying intensity and, from 1987, to trapping, initially by a research organization, and later by a community-based development project. Populations were mainly sampled using odour-baited biconical traps, with data from other monitoring traps corrected accordingly. Mark-release-recapture studies were carried out to relate trap catches to absolute population size, and to quantify movement between subpopulations. Trypanosomiasis incidence rates in a herd of local cattle …


Natural History, Ecology And Potential Environmental Stress Of ̲A̲M̲B̲Y̲S̲T̲O̲M̲A ̲M̲A̲C̲U̲L̲A̲T̲U̲M (Le Conte) And ̲R̲A̲N̲A ̲S̲Y̲L̲V̲A̲T̲I̲C̲A (Shaw) At Dolly Sods, West Virginia, Deborah L. Wegmann Jan 1997

Natural History, Ecology And Potential Environmental Stress Of ̲A̲M̲B̲Y̲S̲T̲O̲M̲A ̲M̲A̲C̲U̲L̲A̲T̲U̲M (Le Conte) And ̲R̲A̲N̲A ̲S̲Y̲L̲V̲A̲T̲I̲C̲A (Shaw) At Dolly Sods, West Virginia, Deborah L. Wegmann

Theses, Dissertations and Capstones

Studies were conducted on the natural history, ecology and potential stress of Ambystoma maculatum and Rana sylvatica at Dolly Sods, West Virginia. Temperature was found to be the primary stimulus influencing spring breeding migration of both species. Breeding period of R. sylvatica was found to be short in duration, resulting in deposition of eggs in large communal masses. Migration and breeding period of A. maculatum occurred from early-April to early-May. Egg deposition occurred from mid-April to mid-May. A second egg deposition of A. maculatum occurred mid-June. Temperature was found to have a significant influence on the rate of development in …


Methodology For Integrating Aerial Photography And Landsat Tm Imagery For Inventory Of Forest Land Cover, Chris W. Bennett, Robert C. Weih Jr. Jan 1997

Methodology For Integrating Aerial Photography And Landsat Tm Imagery For Inventory Of Forest Land Cover, Chris W. Bennett, Robert C. Weih Jr.

Journal of the Arkansas Academy of Science

Forest cover for 7.25 million acres (2.93 million hectares) in southeastern Georgia was characterized for the years 1988 and 1994 with the intent of assessing the efficacy of remote sensing procedures for broad scale forest inventory. Landsat-5 Thematic Mapper digital satellite scenes of seven spectral bands were obtained for winter and summer of each year and were analyzed two separate 14-band multi-temporal images. Images were geo-referenced to the universal transverse mercator (UTM) coordinate system prior to classification. Spectral classification with the 1SOCLUSTER algorithm produced 250 categories. Color infrared aerial photographs were mapped to the digital imagery and were used to …