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2018

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University of Nebraska - Lincoln

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Articles 1 - 30 of 54

Full-Text Articles in Biology

Repeats Of Unusual Size In Plant Mitochondrial Genomes: Identification, Incidence And Evolution, Emily L. Wynn, Alan C. Christensen Dec 2018

Repeats Of Unusual Size In Plant Mitochondrial Genomes: Identification, Incidence And Evolution, Emily L. Wynn, Alan C. Christensen

School of Biological Sciences: Faculty Publications

Plant mitochondrial genomes have excessive size relative to coding capacity, a low mutation rate in genes and a high rearrangement rate. They also have abundant non-tandem repeats often including pairs of large repeats which cause isomerization of the genome by recombination, and numerous repeats of up to several hundred base pairs that recombine only when the genome is stressed by DNA damaging agents or mutations in DNA repair pathway genes. Early work on mitochondrial genomes led to the suggestion that repeats in the size range from several hundred to a few thousand base pair are underrepresented. The repeats themselves are …


Gene Flow Mediates The Role Of Sex Chromosome Meiotic Drive During Complex Speciation, Colin D. Meiklejohn, Emily L. Landeen, Kathleen E. Gordon, Thomas Rzatkiewicz, Sarah B. Kingan, Anthony J. Geneva, Jeffrey P. Vedanayagam, Christina A. Muirhead, Daniel Garrigan, Daven C. Presgraves, David L. Stern Dec 2018

Gene Flow Mediates The Role Of Sex Chromosome Meiotic Drive During Complex Speciation, Colin D. Meiklejohn, Emily L. Landeen, Kathleen E. Gordon, Thomas Rzatkiewicz, Sarah B. Kingan, Anthony J. Geneva, Jeffrey P. Vedanayagam, Christina A. Muirhead, Daniel Garrigan, Daven C. Presgraves, David L. Stern

School of Biological Sciences: Faculty Publications

During speciation, sex chromosomes often accumulate interspecific genetic incompatibilities faster than the rest of the genome. The drive theory posits that sex chromosomes are susceptible to recurrent bouts of meiotic drive and suppression, causing the evolutionary build- up of divergent cryptic sex-linked drive systems and, incidentally, genetic incompatibilities. To assess the role of drive during speciation, we combine high-resolution genetic mapping of X-linked hybrid male sterility with population genomics analyses of divergence and recent gene flow between the fruitfly species, Drosophila mauritiana and D. simulans. Our findings reveal a high density of genetic incompatibilities and a corresponding dearth of gene …


Molecular Machinery Of Auxin Synthesis,Secretion, And Perception In The Unicellular Chlorophyte Alga Chlorella Sorokiniana Utex 1230, Maya Khasin, Rebecca E. Cahoon, Kenneth Nickerson, Wayne R. Riekhof Dec 2018

Molecular Machinery Of Auxin Synthesis,Secretion, And Perception In The Unicellular Chlorophyte Alga Chlorella Sorokiniana Utex 1230, Maya Khasin, Rebecca E. Cahoon, Kenneth Nickerson, Wayne R. Riekhof

School of Biological Sciences: Faculty Publications

Indole-3-acetic acid is a ubiquitous small molecule found in all domains of life. It is the predominant and most active auxin in seed plants, where it coordinates a variety of complex growth and development processes. The potential origin of auxin signaling in algae remains a matter of some controversy. In order to clarify the evolutionary context of algal auxin signaling, we undertook a genomic survey to assess whether auxin acts as a signaling molecule in the emerging model chlorophyte Chlorella sorokiniana UTEX 1230. C. sorokiniana produces the auxin indole-3-acetic acid (IAA), which was present in both the cell pellet and …


Establishing Benchmark Criteria For Single Chromosome Bacterial Genome Assembly, Timothy Krause Dec 2018

Establishing Benchmark Criteria For Single Chromosome Bacterial Genome Assembly, Timothy Krause

School of Biological Sciences: Dissertations, Theses, and Student Research

Adequate recommendations for the amount and types of sequencing data necessary to optimize the recovery of single chromosomes from bacterial sequencing projects do not exist. Broad estimates for coverage depths needed to recover complete bacterial genomes are present in the literature, but required sequencing depths across bacterial and archaeal phylogenies needed for high-quality assembly are not known. Additionally, correlations between genomic complexity and expected quality of assembly have not been properly defined. Furthermore, the capabilities of multiplexing (sequencing more than one sample simultaneously on one flow cell) with long-read sequencing platforms in order to recover complete bacterial chromosomes are poorly …


Examining Patterns In Nest Predation Using Artificial Nests, Victoria L. Simonsen Nov 2018

Examining Patterns In Nest Predation Using Artificial Nests, Victoria L. Simonsen

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

The use of artificial nests to study the predation of avian nests has faced disregard by ecologists due to inconsistencies found between the survival rates of real and artificial nests across studies and reviews. The negative perception of artificial nests providing an inconsistent assessment of survival has thus fostered the perception that artificial nests are a secondary option to be used to overcome logistical hurdles associated with achieving sufficient sample sizes in systems where study species are rare or elusive, or as merely a preliminary method to study predation across gradients. We argue that the greatest mistake ecologists have made …


Modeling Effects Of Ecological Factors On Evolution Of Polygenic Pesticide Resistance, C. V. Haridas, Brigitte Tenhumberg Nov 2018

Modeling Effects Of Ecological Factors On Evolution Of Polygenic Pesticide Resistance, C. V. Haridas, Brigitte Tenhumberg

School of Biological Sciences: Faculty Publications

Widespread use of pesticides has resulted in the evolution of resistance in many insect pests worldwide, limiting their use in pest control. Effective pest and resistance management practices require understanding of the genetics of resistance and the life history of the pest. Most models for pesticide resistance assume that resistance is monogenic, conferred by a single gene. However, resistance could evolve as a polygenic quantitative trait resulting from the action of several genes, especially when pesticide dose is low. Further, fitness of the pest could be density dependent and might depend upon abiotic factors such as temperature. It is not …


Fueling Defense: Effects Of Resources On The Ecology And Evolution Of Tolerance To Parasite Infection, Sarah A. Budischak, Clayton E. Cressler Oct 2018

Fueling Defense: Effects Of Resources On The Ecology And Evolution Of Tolerance To Parasite Infection, Sarah A. Budischak, Clayton E. Cressler

School of Biological Sciences: Faculty Publications

Resource availability is a key environmental constraint affecting the ecology and evolution of species. Resources have strong effects on disease resistance, but they can also affect the othermain parasite defense strategy, tolerance. A small but growing number of animal studies are beginning to investigate the effects of resources on tolerance phenotypes. Here, we review how resources affect tolerance strategies across animal taxa ranging from fruit flies to frogs to mice. Surprisingly, resources (quality and quantity) can increase or reduce tolerance, dependent upon the particular host-parasite system. To explore this seeming contradiction, we recast predictions of models of sterility tolerance and …


Nebraska’S Wildlife Club; Nebraska Honors Program Clc Expanded Learning Opportunity Clubs, Alexandrea E. Otto Oct 2018

Nebraska’S Wildlife Club; Nebraska Honors Program Clc Expanded Learning Opportunity Clubs, Alexandrea E. Otto

Honors Expanded Learning Clubs

The goal of the club is to educate and explore with students the wildlife and nature that surrounds them every day. The main focus was to educate students on wildlife native to Nebraska; ranging all the way from West Nebraska to the wildlife found in cities such as Lincoln.


Males And Females Evolve Riskier Traits In Populations With Eavesdropping Parasitoids, Oliver M. Beckers, William E. Wagner Oct 2018

Males And Females Evolve Riskier Traits In Populations With Eavesdropping Parasitoids, Oliver M. Beckers, William E. Wagner

School of Biological Sciences: Faculty Publications

Predation and/or parasitism often limits the evolution of conspicuous male traits and female preferences because conspicuous traits can attract predators or parasites and it is costly for females to associate with males that attract predators or parasites. As a result, males and females in high-risk populations are expected to evolve safer mating behaviors compared to individuals from low-risk populations. We tested this antagonistic selection hypothesis in the field cricket Gryllus lineaticeps. Males produce chirped songs, and both female crickets and the eavesdropping parasitoid fly Ormia ochracea prefer faster chirp rates. The flies attack the field crickets late in the …


Transcriptomic, Functional, And Network Analyses Reveal Novel Genes Involved In The Interaction Between Caenorhabditis Elegans And Stenotrophomonas Maltophilia, Corin V. White, Michael A. Herman Aug 2018

Transcriptomic, Functional, And Network Analyses Reveal Novel Genes Involved In The Interaction Between Caenorhabditis Elegans And Stenotrophomonas Maltophilia, Corin V. White, Michael A. Herman

School of Biological Sciences: Faculty Publications

The bacterivorous nematode Caenorhabditis elegans is an excellent model for the study of innate immune responses to a variety of bacterial pathogens, including the emerging nosocomial bacterial pathogen Stenotrophomonas maltophilia. The study of this interaction has ecological and medical relevance as S. maltophilia is found in association with C. elegans and other nematodes in the wild and is an emerging opportunistic bacterial pathogen. We identified 393 genes that were differentially expressed when exposed to virulent and avirulent strains of S.maltophilia and an avirulent strain of E. coli. We then used a probabilistic functional gene network model (WormNet) to determine …


Evaluation Of A Human Papillomavirus Genotyping Assay For Cervical Cancer Screening In Tanzania, Kandali Kapie Aug 2018

Evaluation Of A Human Papillomavirus Genotyping Assay For Cervical Cancer Screening In Tanzania, Kandali Kapie

School of Biological Sciences: Dissertations, Theses, and Student Research

Abstract: Mucosal high-risk Human papillomavirus (HR-HPV) has been identified as the primary factor in causing cervical cancer, the most common cancer in women of low and middle-income countries (LMICs). Cervical cancer screening, incorporating the HPV test shown to be more advantageous than screening by visual inspection with acetic acid (VIA) alone. However, due to resources constrain these countries could not afford the available HPV tests. We, therefore, validated a cost-effective Multiplex PCR HPV (mPCR) assay, a recently developed assay for detecting sixteen genital HPV, fourteen HR-HPV and 2 low-risk genotypes. We postulate that this HPV multiplex assay will be …


Contributions Of The Gp120 Variable Loops To Envelope Glycoprotein Trimer Stability In Primate Lentiviruses, Dane Bowder Aug 2018

Contributions Of The Gp120 Variable Loops To Envelope Glycoprotein Trimer Stability In Primate Lentiviruses, Dane Bowder

School of Biological Sciences: Dissertations, Theses, and Student Research

Human Immunodeficiency Virus (HIV) is the etiological agent of AIDS and is responsible for the AIDS pandemic worldwide. According to UNAIDS, as of 2016, there were approximately 36.7 million people living with HIV globally, and 1.8 million new infections that year. While antiretroviral therapies and education continue to reduce these numbers, a preventative vaccine is still required to curb this epidemic. The envelope glycoprotein trimer of HIV, which is the sole protein on the surface of the virus and facilitates entry of the virus into host cells, is of keen interest to the HIV vaccine and drug-development field. Recently, the …


Dehydration Stress Memory: Gene Networks Linked To Physiological Responses During Repeated Stresses Of Zea Mays, Laetitia Virlouvet, Thomas J. Avenson, Qian Du, Chi Zhang, Ning Liu, Michael Fromm, Zoya Avramova, Sabrina E. Russo Jul 2018

Dehydration Stress Memory: Gene Networks Linked To Physiological Responses During Repeated Stresses Of Zea Mays, Laetitia Virlouvet, Thomas J. Avenson, Qian Du, Chi Zhang, Ning Liu, Michael Fromm, Zoya Avramova, Sabrina E. Russo

School of Biological Sciences: Faculty Publications

Stress memory refers to the observation that an initial, sub-lethal stress alters plants’ responses to subsequent stresses. Previous transcriptome analyses of maize seedlings exposed to a repeated dehydration stress has revealed the existence of transcriptional stress memory in Zea mays. Whether drought-related physiological responses also display memory and how transcriptional memory translates into physiological memory are fundamental questions that are still unanswered. Using a systems-biology approach we investigate whether/how transcription memory responses established in the genome-wide analysis of Z. mays correlate with 14 physiological parameters measured during a repeated exposure of maize seedlings to dehydration stress. Co-expression network analysis revealed …


Cross-Ecosystem Effects Of Terrestrial Predators Link Treefrogs, Zooplankton, And Aquatic Primary Production, Jessica L. Hite, Myra C. Hughey, Karen M. Warkentin, James R. Vonesh Jul 2018

Cross-Ecosystem Effects Of Terrestrial Predators Link Treefrogs, Zooplankton, And Aquatic Primary Production, Jessica L. Hite, Myra C. Hughey, Karen M. Warkentin, James R. Vonesh

School of Biological Sciences: Faculty Publications

Predators can directly or indirectly shape food webs through a combination of consumptive and non-consumptive effects. Yet, how these effects vary across natural populations and their consequences for adjacent ecosystems remains poorly resolved. We examined links between terrestrial predators and aquatic ecosystems through their effects on a locally abundant amphibian, the red-eyed treefrog (Agalychnis callidryas), which has arboreal eggs (heavily predated by snakes and wasps) and aquatic larvae; embryos can escape terrestrial threats by hatching at an earlier age and smaller size. Our multi-site field survey indicates that in natural populations, the relative contributions of these consumptive and non-consumptive effects …


A Probable Case Of Incipient Speciation In Schizocosa Wolf Spiders Driven By Allochrony, Habitat Use, And Female Mate Choice, R. Tucker Gilman, Kasey Fowler-Finn, Eileen A. Hebets Jun 2018

A Probable Case Of Incipient Speciation In Schizocosa Wolf Spiders Driven By Allochrony, Habitat Use, And Female Mate Choice, R. Tucker Gilman, Kasey Fowler-Finn, Eileen A. Hebets

School of Biological Sciences: Faculty Publications

There is growing evidence that speciation can occur between populations that are not geographically isolated. The emergence of assortative mating is believed to be critical to this process, but how assortative mating arises in diverging populations is poorly understood. The wolf spider genus Schizocosa has become a model system for studying mechanisms of assortative mating. We conducted a series of experiments to identify the factors that control mate-pair formation in a Schizocosa population that includes both ornamented and nonornamented males. We show that the population also includes two previously unrecognized female phenotypes. One female phenotype mates mostly or exclusively with …


Small Mammals In Cornfields And Associated Peripheral Habitats In Central Nebraska, Tyson J. Spanel, Keith Geluso Jun 2018

Small Mammals In Cornfields And Associated Peripheral Habitats In Central Nebraska, Tyson J. Spanel, Keith Geluso

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

In the Great Plains, many native grasslands have been converted to agricultural fields during the last two centuries. Peripheral habitats along edges of crop fields generally consist of linear habitats along roads, with many of these habitats used by native fauna. Our study examined capture rates and species composition of small mammals in cornfields, herbaceous roadside ditches, and wooded shelterbelts in central Nebraska. We captured nine species of small mammals. The Prairie Vole (Microtus ochrogaster) and Western Harvest Mouse (Reithrodontomys megalotis) were captured almost exclusively in roadside ditches, the White-footed Deermouse (Peromyscus leucopus) was …


Predators Modify The Temperature Dependence Of Life-History Trade-Offs, Thomas M. Luhring, Janna M. Vavra, Clayton E. Cressler, John Delong Jun 2018

Predators Modify The Temperature Dependence Of Life-History Trade-Offs, Thomas M. Luhring, Janna M. Vavra, Clayton E. Cressler, John Delong

School of Biological Sciences: Faculty Publications

Although life histories are shaped by temperature and predation, their joint influence on the interdependence of life-history traits is poorly understood. Shifts in one life-history trait often necessitate shifts in another—structured in some cases by trade-offs— leading to differing life-history strategies among environments. The offspring size–number trade-off connects three traits whereby a constant reproductive allocation (R) constrains how the number (O) and size (S) of offspring change. Increasing temperature and size-independent predation decrease size at and time to reproduction which can lower R through reduced time for resource accrual or size-constrained fecundity. We investigated how O, S, and R in …


Multiple–True–False Questions Reveal The Limits Of The Multiple–Choice Format For Detecting Students With Incomplete Understandings, Brian Couch, Joanna K. Hubbard, Chad Brassil Jun 2018

Multiple–True–False Questions Reveal The Limits Of The Multiple–Choice Format For Detecting Students With Incomplete Understandings, Brian Couch, Joanna K. Hubbard, Chad Brassil

School of Biological Sciences: Faculty Publications

By having students select one answer among several plausible options, multiple–choice (MC) questions capture a student’s preferred answer but provide little information regarding a student’s thinking on the remaining options. We conducted a crossover design experiment in which similar groups of introductory biology students were assigned verbatim questions in the MC format or multiple–true–false (MTF) format, which requires students to separately evaluate each option as either true or false. Our data reveal that nearly half of the students who select the correct MC answer likely hold incorrect understandings of the other options and that the selection rates for individual MC …


Parasite Rearing And Infection Temperatures Jointly Influence Disease Transmission And Shape Seasonality Of Epidemics, Marta S. Shocket, Daniela Vergara, Andrew J. Sickbert, Jason M. Walsman, Alexander T. Strauss, Jessica L. Hite, Meghan A. Duffy, Carla E. Caceres, Spencer R. Hall May 2018

Parasite Rearing And Infection Temperatures Jointly Influence Disease Transmission And Shape Seasonality Of Epidemics, Marta S. Shocket, Daniela Vergara, Andrew J. Sickbert, Jason M. Walsman, Alexander T. Strauss, Jessica L. Hite, Meghan A. Duffy, Carla E. Caceres, Spencer R. Hall

School of Biological Sciences: Faculty Publications

Seasonal epidemics erupt commonly in nature and are driven by numerous mechanisms. Here, we suggest a new mechanism that could determine the size and timing of seasonal epidemics: rearing environment changes the performance of parasites. This mechanism arises when the environmental conditions in which a parasite is produced impact its performance—independently from the current environment. To illustrate the potential for “rearing effects”, we show how temperature influences infection risk (transmission rate) in a Daphnia-fungus disease system through both parasite rearing temperature and infection temperature. During autumnal epidemics, zooplankton hosts contact (eat) fungal parasites (spores) reared in a gradually cooling environment. …


Song Recognition And Heterospecific Associations Between 2 Fairy-Wren Species (Maluridae), Allison E. Johnson, Christina Masco, Stephen Pruett-Jones May 2018

Song Recognition And Heterospecific Associations Between 2 Fairy-Wren Species (Maluridae), Allison E. Johnson, Christina Masco, Stephen Pruett-Jones

School of Biological Sciences: Faculty Publications

Although heterospecific associations beneficial to one or both species involved (e.g. commensalisms or mutualisms) are common, it is generally assumed that interactions between species are transient and not particular to individuals. However, long-term interactions between individuals of different species do occur. In such heterospecific social groups, discrimination between heterospecific individuals may be beneficial, allowing individuals to direct beneficial or aggressive behaviors towards appropriate targets. Here, we describe heterospecific groups composed of splendid and variegated fairy-wrens (Malurus splendens and M. lamberti) and provide the first experimental evidence that recognition of heterospecific group members occurs across species. In these species, …


Morphological Traits As Indicators Of Sexual Dimorphism In Prairie Rattlesnakes (Crotalus Viridis), Colleen Rothe-Groleau, Claudia M. Rauter, James D. Fawcett May 2018

Morphological Traits As Indicators Of Sexual Dimorphism In Prairie Rattlesnakes (Crotalus Viridis), Colleen Rothe-Groleau, Claudia M. Rauter, James D. Fawcett

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

As humans encroach into areas inhabited by predators, the potential of human-predator confrontations increases and the predators become regarded as dangerous pests. Predators exert a measure of population control over pest species such as small rodents, as well as limit the quantity and scope of diseases (e.g. spread of Hantavirus by these prey species). Control of these small rodent pest species can be aided by conserving and managing their predators like rattlesnakes (Crotalus spp). Management of any population requires detailed information on population composition and the ability to determine the key information (especially age and sex) for each individual …


Body Size Downgrading Of Mammals Over The Late Quaternary, Felisa A. Smith, Rosemary E. Elliott Smith, S. Kathleen Lyons, Jonathan L. Payne Apr 2018

Body Size Downgrading Of Mammals Over The Late Quaternary, Felisa A. Smith, Rosemary E. Elliott Smith, S. Kathleen Lyons, Jonathan L. Payne

School of Biological Sciences: Faculty Publications

Since the late Pleistocene, large-bodied mammals have been extirpated from much of Earth. Although all habitable continents once harbored giant mammals, the few remaining species are largely confined to Africa. This decline is coincident with the global expansion of hominins over the late Quaternary. Here, we quantify mammalian extinction selectivity, continental body size distributions, and taxonomic diversity over five time periods spanning the past 125,000 years and stretching approximately 200 years into the future. We demonstrate that size-selective extinction was already under way in the oldest interval and occurred on all continents, within all trophic modes, and across all time …


Energetic Tradeoffs Control The Size Distribution Of Aquatic Mammals, William Gearty, Craig R. Mcclain, Jonathan Payne Apr 2018

Energetic Tradeoffs Control The Size Distribution Of Aquatic Mammals, William Gearty, Craig R. Mcclain, Jonathan Payne

School of Biological Sciences: Faculty Publications

Four extant lineages of mammals have invaded and diversified in the water: Sirenia, Cetacea, Pinnipedia, and Lutrinae. Most of these aquatic clades are larger bodied, on average, than their closest land-dwelling relatives, but the extent to which potential ecological, biomechanical, and physiological controls contributed to this pattern remains untested quantitatively. Here, we use previously published data on the body masses of 3,859 living and 2,999 fossil mammal species to examine the evolutionary trajectories of body size in aquatic mammals through both comparative phylogenetic analysis and examination of the fossil record. Both methods indicate that the evolution of an aquatic lifestyle …


Influenza D Virus M2 Protein Exhibits Ion Channel Activity In Xenopus Laevis Oocytes, Evan Daniel Kesinger Apr 2018

Influenza D Virus M2 Protein Exhibits Ion Channel Activity In Xenopus Laevis Oocytes, Evan Daniel Kesinger

School of Biological Sciences: Dissertations, Theses, and Student Research

The Influenza virus M2 ion channel has good potential as a target for antiviral drugs, as the channel is necessary for viral replication. M2 of Influenza A and B viruses has beenstudied extensively, and is understood to function as a proton channel. Antiviral drugs like amantadine and rimantadine have been used to block the function of Influenza A virus M2. Influenza C virus M2 has also been researched and is understood to act as a chloride ion channel. However, the M2 channel of Influenza D virus (DM2) has been studied very little, and the activity and mechanism of the channel …


Factors Affecting The Parasitism Of Gregarine Species In Grasshoppers In Western Nebraska, Alexandra Creigh, Kristin Mclarty, Scott Lyell Gardner Mar 2018

Factors Affecting The Parasitism Of Gregarine Species In Grasshoppers In Western Nebraska, Alexandra Creigh, Kristin Mclarty, Scott Lyell Gardner

Honors Theses

We conducted a survey of the species of parasites found in grasshoppers around the area of Dunwoody’s Pond to investigate whether there were any species specific parasitic relationships occurring there. We collected grasshoppers from several areas around Dunwoody’s Pond totaling 15 species including Melanoplus bivittatus (Say 1825) , Melanoplus sanguinipes (Fabricius, 1798) , Melanoplus differentialis (Thomas 1865), and Melanoplus femurrubrum (De Geer 1773), along with others (Seymour et al., 2009) and compared the parasites found in them. This study is similar to one conducted in South America by Lloyd in 1951, and we hoped to find connections between species to …


Olfactory Learning Capabilities Of Paraphrynus Laevifrons, John Perez Mar 2018

Olfactory Learning Capabilities Of Paraphrynus Laevifrons, John Perez

Honors Theses

Amblypygids, a species of nocturnal arachnids from the tropics and subtropics are incredibly intelligent and are able to not only navigate through difficult tropical terrain but also, it is believed, possess olfactory learning capabilities that aid in navigation and recollection of environments. It is hypothesized that through sensitive olfactory receptors on their antenniform legs and highly developed mushroom bodies, Amblypygi can not only learn smells but also learn to associate smells with certain stimuli such as a crevice to take refuge in. To test this hypothesis, Paraphrynus laevifrons, a species of amplypygid was subjected to four different learning treatment groups …


Genetic Diversity And Distinctness Of Wild Nebraska Hops And Hop Cultivars (Humulus Lupulus L.), Megan Franklin Mar 2018

Genetic Diversity And Distinctness Of Wild Nebraska Hops And Hop Cultivars (Humulus Lupulus L.), Megan Franklin

Honors Theses

Background Commercial hop (Humulus lupulus) cultivars that are being grown in the Midwest are not performing as successfully as when they are grown in the Pacific Northwest, the region to which they are adapted. To increase adaptation to the Midwest environment, one strategy is to draw from the genetic pool of wild native Midwest hops, which have developed genes that allow them to grow successfully in this environment. Wild hop plants that are genetically distinct from commercial cultivars are likely to have more adaptations, such as pest/disease resistance and drought tolerance, which can be bred into commercial lines. The …


Temperature Drives Epidemics In A Zooplankton-Fungus Disease System: A Trait-Driven Approach Points To Transmission Via Host Foraging, Marta S. Shocket, Alexander T. Strauss, Jessica L. Hite, Maja Šljivar, David J. Civitello, Meghan A. Duffy, Carla E. Cáceres, Spencer R. Hall Feb 2018

Temperature Drives Epidemics In A Zooplankton-Fungus Disease System: A Trait-Driven Approach Points To Transmission Via Host Foraging, Marta S. Shocket, Alexander T. Strauss, Jessica L. Hite, Maja Šljivar, David J. Civitello, Meghan A. Duffy, Carla E. Cáceres, Spencer R. Hall

School of Biological Sciences: Faculty Publications

Climatic warming will likely have idiosyncratic impacts on infectious diseases, causing some to increase while others decrease or shift geographically. A mechanistic framework could better predict these different temperature-disease outcomes. However, such a framework remains challenging to develop, due to the nonlinear and (sometimes) opposing thermal responses of different host and parasite traits and due to the difficulty of validating model predictions with observations and experiments. We address these challenges in a zooplanktonfungus (Daphnia dentifera–Metschnikowia bicuspidata) system. We test the hypothesis that warmer temperatures promote disease spread and produce larger epidemics. In lakes, epidemics that start earlier and warmer in …


Eight-Legged Encounters—Arachnids, Volunteers, And Art Help To Bridge The Gap Between Informal And Formal Science Learning, Eileen Hebets, Melissa Welch-Lazoritz, Pawl Tisdale, Patricia Wonch Hill Feb 2018

Eight-Legged Encounters—Arachnids, Volunteers, And Art Help To Bridge The Gap Between Informal And Formal Science Learning, Eileen Hebets, Melissa Welch-Lazoritz, Pawl Tisdale, Patricia Wonch Hill

Eileen Hebets Publications

Increased integration and synergy between formal and informal learning environments is proposed to provide multiple benefits to science learners. In an effort to better bridge these two learning contexts, we developed an educational model that employs the charismatic nature of arachnids to engage the public of all ages in science learning; learning that aligns with the Next Generation Science Standards (NGSS Disciplinary Core Ideas associated with Biodiversity and Evolution). We created, implemented, and evaluated a family-focused, interactive science event—Eight-Legged Encounters (ELE)—which encompasses more than twenty modular activities. Volunteers facilitated participant involvement at each activity station and original …


Effects Of Elevated Co2, Increased Nitrogen Deposition, And Plant Diversity On Aboveground Litter And Root Decomposition, Xiaoan Zuo, Johannes Knops Feb 2018

Effects Of Elevated Co2, Increased Nitrogen Deposition, And Plant Diversity On Aboveground Litter And Root Decomposition, Xiaoan Zuo, Johannes Knops

School of Biological Sciences: Faculty Publications

Global change-induced litter decomposition strongly affects the carbon (C) and nitrogen (N) dynamics in grassland ecosystems. However, few studies show the interactive effects of global change factors on litter and root decomposition. We conducted a four-year grassland field experiment to examine the quality and decomposition of litter and root in a three-factorial experiment with elevated CO2, increased N deposition, and plant species richness. We found that elevated CO2 decreased the litter N content and root lignin content. N addition increased the root N content and decreased the litter lignin content. Increasing plant richness decreased the N and …