Digital Commons Network^™

Nsf Grant Helps Preserve Parasite Collections [Press Release], Scott Gardner, Leslie Reed

Scott L. Gardner Publications

The National Science Foundation has awarded a $500,000 grant that will allow four major parasite collections to be digitized. The collections are part of UNL's Harold W. Manter Laboratory of Parasitology. Scott Gardner (pictured) is the curator and director of the Manter Laboratory.

A $500,000 grant from the National Science Foundation will allow the Harold W. Manter Laboratory of Parasitology to digitally preserve four major collections of parasite specimens donated to the University of Nebraska-Lincoln during the past five years.

Social Network Analysis Of Partner Preference In Lemon Sharks, Negaprion Brevirostris, During The Introduction Of Unfamiliars To Familiar Groups, Bryan Keller

Electronic Theses and Dissertations

In order to understand what drives group formations and to predict spatial occurrences, investigations on individual preferences within the groups have proved to be very useful. Groups of sharks have been observed for centuries; however, there is a dearth of quantitative analyses on the mechanisms that drive their formation. In this study, we use controlled, semi-captive behavioural experiments to assess the potential role of familiarity in group formation and on social behaviour in a large marine vertebrate. Juvenile lemon sharks, Negaprion brevirostris, (n =23) in Bimini, Bahamas were captured, measured and tagged with external colour codes for individual identification and …

Phylogenetically Novel Species Are More Successful Due To High Competitive Ability At Local And Regional Scales, Amy C. Patterson

Senior Honors Papers / Undergraduate Theses

While few introduced exotic species become invasive, this small number of species poses serious threats to biodiversity, ecosystem function, and recreation, leading ecologists to study why certain species become invasive and why certain communities are prone to invasions. Several leading hypotheses seek to explain invasiveness, including the Enemy Release Hypothesis, the trait superiority hypothesis, and the Biotic Resistance Hypothesis, but none are consistently supported in the literature. We suggest that the lack of uniting hypothesis is a result of the inability to put multiple proposed mechanisms in the same framework, and suggest for a uniting framework Darwin’s Naturalization Hypothesis along …

Effects Of Human Recreational Activity On The Tameness Of Common Loons (Gavia Immer) In Northern Wisconsin, Seth Yund

Student Scholar Symposium Abstracts and Posters

The Common Loon (Gavia immer) is an aquatic diving bird that lives in freshwater habitats in Canada and the northern U.S.. Human activity on a loon’s resident lake may affect its fitness and behavior, yet few studies identify or quantify these effects. We modified existing techniques that measure escape distances in other species to measure tameness as the distance at which individual loons dove in response to human approach by canoe. Tameness was similar between pair members, suggesting that common lake conditions or the behavior of a mate might influence the behavior. Sex, size within sex, and human activity did …

Effects Of El Niño On Ecological Growth Along Californian And Peruvian Coasts, Alexandra Sidun

Student Scholar Symposium Abstracts and Posters

This study examines the mechanisms of El Niño to further understand the ecological effects it may have along the Californian and Peruvian coasts. El Niño is the warm phase of the El Niño Southern Oscillation (ENSO). While it is a global phenomenon, these two locations were investigated for their nearly equal and opposite conditions during storm months. California, which is in an extreme state of drought, often receives heavy rainfall during El Niño and understanding its potential effects is crucial. El Niño causes upwellings along the CA coast and warm water from the region displaces the normally cool waters along …

Social Communication Of Predator-Induced Changes In Drosophila Behavior And Germ Line Physiology, Balint Z. Kacsoh, Julianna Bozler, Mani Ramaswami, Giovanni Bosco

Dartmouth Scholarship

Behavioral adaptation to environmental threats and subsequent social transmission of adaptive behavior has evolutionary implications. In Drosophila, exposure to parasitoid wasps leads to a sharp decline in oviposition. We show that exposure to predator elicits both an acute and learned oviposition depression, mediated through the visual system. However, long-term persistence of oviposition depression after predator removal requires neuronal signaling functions, a functional mushroom body, and neurally driven apoptosis of oocytes through effector caspases. Strikingly, wasp-exposed flies (teachers) can transmit egg-retention behavior and trigger ovarian apoptosis in naive, unexposed flies (students). Acquisition and behavioral execution of this socially learned behavior …

Comparing Pseudo-Environmental And Horizontal Plus Pseudo-Environmental Transmission Of A Probiotic Janithinobacterium Lividum Between Green Frog Tadpoles, Stephen Simonetti

Senior Honors Projects, 2010-2019

The gram-negative bacteria, Janthinobacterium lividum (J.liv) is able to kill the pathogenic fungus known as Batrachochytrium dendrobatidis (Bd), which is known to be causing massive amphibian decline worldwide. The purpose of this research was to identify the ability of the probiotic bacteria, Janthinobacterium lividum (J.liv), to be horizontally transmitted from individual to individual and/or pseudo-environmentally transmitted from individual to environment and back to individual between Lithobates clamitans (green frog) tadpoles. Based on previous findings I hypothesized that pseudo-environmental and horizontal transmission will occur in tadpoles. This would be important for helping stop the decline of amphibians because it would provide …

Comparative Analysis Of Anti-Bd Bacteria From Six Malagasy Frog Species Of Ranomafana National Park, Kelsey Savage

Senior Honors Projects, 2010-2019

As Malagasy amphibians are facing an impending extinction crisis from the lethal skin fungus Batrachochytrium dendrobatidis (Bd), it has become imperative to proactively mitigate the threat. Bd sporangia develop in the skin of infected amphibians and cause the skin to thicken, leading to ionic imbalance and eventual heart failure. It has been shown that certain bacterial species are able to inhibit Bd growth on amphibians by producing antifungal metabolites. Community-based probiotics are one approach used to combat chytridomycosis by inoculating an environment with Bd-inhibitory bacteria so that many amphibian species are treated at once. With this method, it is important …

Experimental Greenhouse And Field Trials On American Ginseng, Panax Quinquefolium: Implications For Restoration In Appalachia, Emily Thyroff

Senior Honors Projects, 2010-2019

Panax quinquefolium, American ginseng, is one of the more valuable non-timber forest products, NTFPs, providing economic, cultural, and ecological ecosystem services in forests. Although ginseng has a broad distribution range, it is not abundant anywhere due to overharvesting and deer browse. This study included experimental field and greenhouse trials to determine optimal growing conditions given inconsistencies regarding aspect and soil. Three soil series and two aspects (represented by soil moisture in the greenhouse) were manipulated in a factorial design. We hypothesized that there would be significant differences in ginseng performance (germination, survival, leaf area, and height) due to soil and …

Insomniac Of The Soil: A Collection Of Poetry And Essays, Sarah E. Golibart

Senior Honors Projects, 2010-2019

“Insomniac of the Soil” is a homage to a landscape that has deeply informed Sarah Golibart's life and her artistic voice – the tidewater flatlands of Virginia’s Chesapeake Bay peninsula where her family lives and where Golibart has worked on farms since high school. Both her poems and essays are earthy, imagistic, and grounded – quite literally – in the soil as well as in a sensibility of ecological ethics and sustainability. “Insomniac of the Soil” is also a love song to the fervent and fallow cycles of the soil.

Fishing For A Sustainable Future: Aquaponics As A Method Of Food Production, Richard Ramsundar

Student Theses 2015-Present

This thesis compares and explains the advantages aquaponics farming has over modern industrial intensive farming. Through a comparison natural capital usage, conservation, recycling and cost, the thesis advocates for the expansion of aquaponics usage in urban settings. The thesis also explains the history of intensive farming and aquaponics in America, the science of how aquaponics operates, the economic and environmental costs of modern intensive farming versus aquaponics farming, and the social implications of aquaponics. Lastly, I propose a policy that reallocates farm subsidies by modifying the Farm Bill. Then I propose policies that support creating a new standard of farm …

Distributional Expansion Of The Hispid Cotton Rat (Sigmodon Hispidus) Into Dawson County, Nebraska, Jennifer D. Frisch, Keith Geluso, Joseph T. Springer

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

In the last century, the Hispid Cotton Rat (Sigmodon hispidus) has moved northward in central parts of the United States, reaching Nebraska in the late 1950s. Recent surveys demonstrate Hispid Cotton Rats inhabit counties across southern parts of Nebraska south of the Platte River. Herein, we report on captures of S. hispidus from a new county (Dawson County), its seasonal occurrence at our study site, and the first known record of the Hispid Cotton Rat north of channels of the Platte River. Our captures represent one of the northern-most records in Nebraska.

The Effect Of Controlled Burns On Abundance Of Woody Species At Buck Mountain, West Virginia, Barry E. Edgar

Masters Theses, 2010-2019

Each year, the U.S. Forest Service prescribes burns within the George Washington and Jefferson National Forest (GWJNF). Burns are prescribed in the growing (late April-October) and dormant season (November- mid-April). The goal of the burns is to reinstate the natural fire regime, returning forests to their original species composition. Currently in GWJNF, Appalachian pine-oak forests are experiencing an increase in fire-intolerant species, while Quercus species and Gaylussacia brachycera, an endangered shrub species, are declining. In the summer of 2014, a vegetation survey was conducted on Buck Mountain, West Virginia to determine if there was a significant difference between dormant and …

Using Capture-Mark-Recapture Techniques To Estimate Detection Probabilities & Fidelity Of Expression For The Critically Endangered James Spinymussel (Pleurobema Collina)., Alaina C. Esposito

Masters Theses, 2010-2019

The critically endangered James Spinymussel (Pleurobema collina) is a species of freshwater mussel endemic to Virginia’s James and Dan River basins. In the last 20 years, P. collina has experienced a substantial decline in numbers and currently occupies approximately 10% of its original habitat; however, little information is known about this species to assist in conservation. A 230-meter reach of transitional habitat in Swift Run was selected for repeat observations to estimate detection probabilities using a Capture-Mark-Recapture framework. In June 2014, visual scouting began to locate and tag P. collina (including other mussels in the community) with PIT …

Teaching Evolution: A Students’ Perspective, Abdullah Allaoa, Tyniqua Hinton

Publications and Research

Many may wonder “where do we come from?” Over time, scientists have pondered and tested the concept of evolution. Simply put, evolution is gradual change over time. A major tenet of evolution is natural selection, which includes three principles which are variation in population, differential reproduction due to competition, and heredity. These principles are supported by multiple lines of evidence, including biochemical, geographical, fossil, and anatomical evidence. By providing tangible, real-world examples of evolution, we hope to provide a clear understanding of this long-studied scientific breakthrough, while at the same time showing how animals (including us) are related to each …

Does Reproductive Investment Decrease Telomere Length In Menidia Menidia?, Jin Gao, Stephan B. Munch

Department of Biomedical Engineering Faculty Publications

Given finite resources, intense investment in one life history trait is expected to reduce investment in others. Although telomere length appears to be strongly tied to age in many taxa, telomere maintenance requires energy. We therefore hypothesize that telomere maintenance may trade off against other life history characters. We used natural variation in laboratory populations of Atlantic silversides (Menidia menidia) to study the relationship between growth, fecundity, life expectancy, and relative telomere length. In keeping with several other studies on fishes, we found no clear dependence of telomere length on age. However, we did find that more fecund …

Effects Of The Developmental Environment On Oxidative Damage And Antioxidants In Red-Eared Slider Turtle ( Trachemys Scripta Elegans ) Hatchlings, Lisa Allison Treidel

Theses and Dissertations

Developmental environments influence many individual phenotypes. However, currently we have a limited understanding of how the developmental environment influences oxidative stress resistance phenotypes. Oxidative stress is defined as a physiological state during which the production of harmful free radicals exceeds the protective capabilities of antioxidants. Variations among adults in susceptibility to oxidative stress can have important consequences for life history strategies and fitness related traits. Our work was aimed at providing insight in to the role that the developmental environment plays on oxidative stress phenotypes in the model oviparous reptile the red-eared slider turtle (Trachemys scripta elegans). Here, we conducted …

Phylogeography Of Darlingtonea Kentuckensis And Molecular Systematics Of Kentucky Cave Trechines, Olivia Frances Boyd

Masters Theses & Specialist Projects

The monotypic cave carabid genus Darlingtonea is widely distributed along the eastern band of the Mississippian/Pennyroyal plateau in Kentucky and northern Tennessee. DNA sequence data from the mitochondrial gene cytochrome oxidase subunit I (COI) was collected from one to four individuals from 27 populations, and patterns of phylogeography and population structure were inferred from COI haplotypes. A hierarchical analysis of molecular variance found low nucleotide diversity within populations and statistically significant variation among geographically-defined groups tested based on two a priori hypotheses of structure. Population structure among five distinct genetic clusters identifies approximate locations of barriers to gene flow among …

Fisheries Management Paper No 274 - Finfish Resources Of The Peel-Harvey Estuary - Harvest Strategy 2015-2020 (Version 1.0), Department Of Fisheries, Western Australia

Fisheries Management Papers

WEST COAST ESTUARINE MANAGED FISHERY (AREA 2)

Harvest strategies for aquatic resources managed by the Western Australian Department of Fisheries (the Department) are formal documents prepared to support the decision-making processes required to ensure the management of these resources are consistent with the principles of Ecologically Sustainable Development (ESD). The objectives of ESD are reflected in the objects of the Fish Resources Management Act 1994 (FRMA), Section 3, and the draft Aquatic Resources Management Bill 2013 (ARMB), Clause 9, which will replace the FRMA once enacted.

The publication of these strategies is intended to make the decision-making considerations and processes …

Multi-Level Adjustments In Singing Behavior By A Migratory Songbird In Response To Urbanization, Jacob Job

Dissertations

The spread of high-amplitude anthropogenic noise across natural landscapes is a serious issue for vocally communicating animals. Noise disrupts communication, which has implications for individual fitness and population persistence. In response, animals adjust their vocal signals with increasing noise. As the increase in noise has occurred on a relatively short time scale, evolutionary responses are likely not the primary cause of adjustments. Instead, short-term behavioral adjustments may drive population differences; however, such adjustments are currently not well understood. Moreover, noise is only one characteristic of urbanized landscapes and whether other characteristics, such as highly reverberant surfaces interact with noise to …

Rareness Starts Early For Disturbance-Dependent Grassland Plant Species, Matthew Candeias

Biology Theses

Ecological communities always contain a few common species and an abundance of rare species. Mechanisms determining commonness and rarity require experimental investigation. Given that most plant mortality occurs in seeds and seedlings, recruitment best predicts plant community assemblage and distributions. In northeastern North America, grassland plant species constitute a sizable portion of the native flora. Approximately 30% of western New York’s threatened and endangered flora are associated with grasslands, apparent leftovers from a post-glacial landscape. I investigated the mechanisms behind grassland species commonness and rarity by examining how habitat type, disturbance and biotic interactions limit seed recruitment for three rare …

Forest Sustainability In An Altered Landscape Requires Human Intervention, Adam C. Labatore

Biology Theses

Recruitment success determines the abundance and composition of plant communities. Successful recruitment can be summarized as a simple dichotomy of establishment versus seed limitations. Establishment limitation occurs when plant populations are inhibited by habitat availability and quality, whereas seed limitation occurs when seeds fail to arrive in necessary densities. Recruitment failure undermines overstory sustainability if the existing trees cannot replace themselves. Preliminary analysis indicated tree recruitment failure at an urban nature preserve with too few tree seedlings to replace mature canopy trees. These data suggested that the urban forest was not sustainable. The overarching goal of the study was to …

Management Of A Primordial Problem: Redox-Sensitive Transcriptional Regulation In Methanosarcina Acetivorans, Ryan Christopher Sheehan

Graduate Theses and Dissertations

The primordial Earth which hosted the first forms of life was an environment free of oxygen. Early organisms utilized metabolisms dependent upon anaerobic conditions and incorporated systems to which oxygen is deleterious. As the content of oxygen in Earth's atmosphere increased, anaerobic organisms had to acquire methods to sense and combat oxygen and reactive oxygen species. Several mechanisms were advantageous to such anaerobic organisms which correlated transcriptional processes with the redox state of the cell so that energy may be conserved and oxygen stress recovery genes activated during periods of oxidative stress. Iron sulfur (Fe-S) cluster cofactors incorporated within RNA …

The Reproductive Ecology Of The Timber Rattlesnake, Crotalus Horridus, In Northwestern Arkansas: Interactions Between Environment, Steroid Hormones, And Life History, Craig Michael Lind

Graduate Theses and Dissertations

In this dissertation I examined the relationship between individual energetic status, hormone production, and life history trait expression in field-active Timber Rattlesnakes, Crotalus horridus. In chapter one I reviewed what is known regarding these relationships in snakes and defined major research goals. In chapter two I described the seasonal profile of testosterone (T) and corticosterone (CORT) in relation to the breeding season and to individual energetic status in males. Results showed that the seasonal pattern of T production in C. horridus was different than other pit viper species with similar mating patterns. Testosterone was elevated in the months leading up …

Distribution Of The Egyptian Goose (Alopochen Aegyptiacus) In Northwestern Arkansas And In The United States Of America, Cameron Chesbro

Graduate Theses and Dissertations

The Egyptian Goose (Alopochen aegyptiacus) is an exotic member of the Anatidae that has been residing in northwestern Arkansas since the 1980s (Smith and James 2012). Following the discovery of Egyptian Geese in the area, not much attention has been given to the consequences of population increase. The Egyptian Goose has shown many diverse population growth patterns in areas where it has been introduced and started feral populations. The purpose of this study was to assess the current population size of the Egyptian Goose in northwestern Arkansas,and confirm successful breeding. The methods used in this study included conducting road surveys …

Improving Production Efficiency Of Beef Cow-Calf Operations, Amanda Jo Davis

Graduate Theses and Dissertations

Three studies were conducted to improve and incorporate reproductive management practices into beef cow-calf production. First study evaluated serial use of Estrotect estrous detection patches as a simple, cost-effective reproductive management tool to identify cyclic animals before breeding, distinguish between females conceiving to AI versus natural service, and determine seasonal pregnancy rate after bull removal. Also determined, was effectiveness of altered timing of GnRH treatment (1 d ± CIDR removal) in a modified 14-d CIDR-Select Synch protocol. When evaluated over a 4-wk period, estrous detection patches correctly (P < 0.01) identified 79% of cyclic and 86% of non-cyclic heifers. Patches were 96 and 98% accurate in identifying heifers and cows pregnant by AI, respectively, and were 76 and 87% accurate in identifying pregnant heifers and cows at the end of the breeding season (P < 0.01). Treatment with GnRH at CIDR removal reduced labor costs and animal handling without compromising estrous response (both ~63.0%) and AI pregnancy rates (~76 and 77%; P > 0.1). Second study determined if addition of PGF2alpha treatment on d 7 …

Acute Toxicity Of Β-N-Methylamino-L-Alanine (Bmaa) To Fathead Minnow (Pimephales Promelas) And Zebrafish (Danio Rerio), Jiayi Wang

School of Natural Resources: Dissertations, Theses, and Student Research

β-N-methylamino-L-alanine (BMAA) is a neurotoxic amino acid produced by most species of cyanobacteria. Exposure to BMAA has been hypothesized as a cause of ALS and possibly Parkinson’s and Alzheimer’s diseases for several decades. Both in vitro and in vivo experiments revealed that exposure to elevated concentrations of BMAA can damage motor neurons and cause motor dysfunctions. However, the exact mechanism of BMAA-induced neurotoxicity has not been well understood.

Based on the available literature and in spite of its water-soluble and non-protein nature, BMAA appears to be able to bioaccumulate in organisms. The ubiquity of cyanobacteria and the potential for bioaccumulation …

Genetic And Morphological Variation In Ecuadorian Astroblepid Catfishes, Katherine M. Lawry

School of Natural Resources: Dissertations, Theses, and Student Research

The Andean ichthyofauna remains a poorly understood component of Neotropical biodiversity, and stands in stark contrast to the lowland ichthyofauna in terms of number of species and range of distribution. The Climate Variability Hypothesis (CVH) predicts rapid turnover of species along elevational gradients in tropical climates, but it remains unclear whether stream fishes follow this pattern. Astroblepid catfishes represent a distinctive assemblage of species that inhabit high elevation streams throughout the Andes from Panama to Bolivia, and constitute the only native fish family present in the Ecuadorian highland region. In this research, population samples of Astroblepids collected throughout Ecuador’s Napo …

Plant Diversity Affects Performance Of Invasive Thistles In Restored Nebraska Grasslands, Katilyn J. Price

School of Natural Resources: Dissertations, Theses, and Student Research

Invasive plant species threaten native grasslands, affecting nutrient cycling, biodiversity, wildlife habitat, and usable land for production. Consequently, preventing establishment of invasive species is critical before removal becomes difficult and expensive. The purpose of this study was to examine the effects of grassland plant diversity on musk thistle (Carduus nutans) and Canada thistle (Cirsium arvense) establishment and determine which environmental factors (light penetration, soil moisture, plant diversity, and soil nitrogen) account for resistance to invasions. In a field experiment at The Nature Conservancy’s Wood River site (Nebraska), the two invasive thistle species were planted into replicated …

Habitat And Site Selection Of Pheasants And Their Hunters During The Hunting Season, Lindsey Messinger

School of Natural Resources: Dissertations, Theses, and Student Research

Predator-prey interactions are dynamic and complex with implications for predators, prey, and entire ecological communities. Though predation has obvious mortality costs for prey, equally strong non-consumptive impacts of predation have been the focus of recent studies. Not only are prey affected by their predators through both consumption and fear of predation, but predators are driven by selection to respond to prey behavior. Here, we show how habitat decisions made by highly mobile predators and prey are dynamically linked. In our study system, recreational hunters (predators) make decisions about where to hunt based on a variety of resources (potential prey abundance, …