Digital Commons Network^™

Transcriptional Regulation Of The Synthesis And Secretion Of Farnesol In The Fungus Candida Albicans: Examination Of The Homann Transcription Regulator Knockout Collection, Daniel Gutzmann, Jaxon J. Kramer, Brigid M. Toomey, Cory Honsinger Thomas Boone, Audrey L. Atkin, Kenneth Nickerson

School of Biological Sciences: Faculty Publications

Candida albicans is an efficient colonizer of human gastrointestinal tracts and skin and is an opportunistic pathogen. C. albicans exhibits morphological plasticity, and the ability to switch between yeast and filamentous morphologies is associated with virulence. One regulator of this switch is the quorum sensing molecule farnesol that is produced by C. albicans throughout growth. However, the synthesis, secretion, regulation, and turnover of farnesol are not fully understood. To address this, we used our improved farnesol assay to screen a transcription regulator knockout library for differences in farnesol accumulation in whole cultures, pellets, and supernatants. All screened mutants …

Transcriptional Regulation Of The Synthesis And Secretion Of Farnesol In The Fungus Candida Albicans: Examination Of The Homann Transcription Regulator Knockout Collection, Daniel Gutzmann, Jaxon J. Kramer, Brigid M. Toomey, Cory Honsinger Thomas Boone, Audrey L. Atkin, Kenneth Nickerson

School of Biological Sciences: Faculty Publications

Candida albicans is an efficient colonizer of human gastrointestinal tracts and skin and is an opportunistic pathogen. C. albicans exhibits morphological plasticity, and the ability to switch between yeast and filamentous morphologies is associated with virulence. One regulator of this switch is the quorum sensing molecule farnesol that is produced by C. albicans throughout growth. However, the synthesis, secretion, regulation, and turnover of farnesol are not fully understood. To address this, we used our improved farnesol assay to screen a transcription regulator knockout library for differences in farnesol accumulation in whole cultures, pellets, and supernatants. All screened mutants produced …

Beef Color And Tenderness Response To Production Systems Utilizing Additive Combinations Of Growth-Promotant Technologies, Megan J. Webb, Janna J. Block, John R. Jaeger, R. Funston, Michael G. Gonda, Keith R. Underwood, Judson K. Grubbs, Kenneth C. Olson, Amanda D. Blair

West Central Research and Extension Center, North Platte

The objective of this study was to compare the influence of beef production systems using additive combinations of growth-promotant technologies on meat quality. Steer calves (n = 120) were assigned to 1 of 4 treatments: 1) no technology (NT; control), 2) antibiotic treated (ANT; NT plus therapeutic antibiotics, monensin, and tylosin), 3) implant treated (IMP; ANT plus a series of three implants), and 4) beta-agonist treated (BA; IMP plus ractopamine-HCl). Muscle biopsy samples from the longissimus lumborum were extracted from a subset (n = 4 per treatment) of steers to evaluate expression of calpain-1, calpain-2, and calpastatin using …

Light Alters Leaf Breakdown Rates And Metabolic Activity In Anthropogenically Impacted Nebraska Streams, William Reilly Farrell

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

Algal growth influences carbon breakdown rates in aquatic ecosystems; however, the magnitude and direction of these effects differ based on ecosystem context. To explore algal priming effects on decomposition in anthropogenically impacted ecosystems, I conducted light manipulation experiments in three streams, each surrounded by different land uses (i.e., predominantly urban, row crop, or concentrated animal feeding operation) across Nebraska. I measured leaf breakdown rates, metabolic activity, fungal and algal biomass, and leaf percent carbon (C) and phosphorus (P) to assess the effect of light differences. These streams were impacted by sedimentation and turbidity over the course of the leaf incubation. …

Pronghorn Survival And Resource Selection In Western Nebraska's Agriculturally Dominated Landscape, Katie Piecora

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

Nebraska’s pronghorn population has been stable over the last decade, yet their presence on the landscape remains a contentious subject amongst private landowners. Conversion of grassland for crop production and increased anthropogenic activity has drastically altered pronghorn behavior throughout their current range, however basic ecology and resource use by pronghorn in Nebraska remains poorly understood. Establishing baseline population metrics and seasonal patterns of resource use for this population at the eastern periphery of the species range is critical to guide management actions. We deployed GPS collars on 110 adult pronghorn to quantify survival, mortality risk, and seasonal resource selection in …

Public Mediations Of Accountability In The #Metoo Era, Amanda Brand

Department of Communication Studies: Dissertations, Theses, and Student Research

Tarana Burke initially launched the Me Too movement to cultivate solidarity among sexual assault survivors in 2006, and public appropriations of this effort have resulted in a kairotic moment of accountability in sexual assault cases. Particularly, the 2017 hashtag, #MeToo populates media platforms as the public invokes it to make sense of sexual assault cases, bearing witness to victim-survivors, assigning blame, or disavowing culpability. Challenging legacies of public denial, #MeToo marks a cultural shift in which victim-survivors are not only speaking out, they are also being heard and believed. I argue that accountability is rhetorically-constructed, negotiated, and imposed through …

Increasing Rye Cover Crop Biomass Production After Corn Residue Removal To Balance Economics And Soil Health, Sabrina J. Ruis, Humberto Blanco-Canqui, Paul J. Jasa, Glen Slater, Richard B. Ferguson

Department of Agronomy and Horticulture: Faculty Publications

Low or variable cover crop (CC) biomass production could limit CC benefits. Longer CC growing periods via late termination could increase CC benefits, especially under limited crop residue return. We studied whether early (2–3 wk before planting)- or late (at planting)-terminated winter rye (Secale cereale L.) CC maintains soil properties, crop yields, and farm income under 0%, 25%, 50%, 75%, and 100% corn (Zea mays L.) residue removal in rainfed and irrigated no-till in the U.S. Great Plains after 6 yr. Early-terminated CCs produced < 1 Mg ha^-1 of biomass while late-terminated CCs averaged 1.6 Mg ha^-1 at the rainfed …

Distribution Of The Soft Tick Carios Vespertilionis In Lowlands And Low Mountain Regions Of Germany, Anja Fritzsche, Stefan Zaenker, Jannis Gottwald, Renate Keil, Christian Zaenker, Michael Bröker, Lidia Chitimia-Dobler

Harold W. Manter Laboratory of Parasitology: Library Materials

In Germany, the knowledge about ticks infesting bats is limited, and is restricted only to a few studies, most of them dating back decades. To further improve our knowledge on ticks parasitising bats, healthy and sick bats in central Germany were examined for ticks. In total 519 larvae and one nymph of Carios vespertilionis were collected from nine bat species: Eptesicus nilssonii, Eptesicus serotinus, Myotis daubentonii, Myotis myotis, Nyctalus leisleri, Pipistrellus nathusii, Pipistrellus pygmaeus, Pipistrellus pipistrellus, and Vespertilio murinus. Either the presence of C. vespertilionis was new for some areas or it was confirmed in some federal states in …

On The Economics Of The Transition To A Circular Economy, Ahmed Chennak, Konstantinos Giannakas, Tala Awada

Department of Agricultural Economics: Faculty Publications

Humanity is facing complex challenges posed by population growth, climate change, and the need to increase food, feed, fiber, and bioenergy production while confronting the scarcity of natural resources. The transition to a circular economy, characterized by reduced resource use and waste, is being increasingly recognized in academic, business, and policy making circles as essential to meeting these challenges, with the emphasis being on the development of methods and processes that enable and facilitate the transition from a linear to a circular economy. This paper argues the need for an increased emphasis on the economics of the circular economy and …

Exploring The Relationships Between Mammalian Functional Trait Distributions And Regional Biomes, With Application To Miocene Paleoecology, Devra Hock-Reid

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Paleoecology relies on understanding relationships between modern animals and their environment. Animals are adapted to niches in their environments, and those physical adaptations, or functional traits, are utilized as proxies to interpret aspects of paleo-ecosystems. Much is known about individual functional traits in extant mammals and their relationship to the environment. Less is known about how multiple functional traits across a community can be utilized for paleoecological interpretations. I develop models utilizing traits in mammalian communities at the biome level. For Chapter 1, I build a model for North American regional biomes using mammalian trait frequencies. I quantify changes in …

Unraveling Prevalence And Effects Of Deleterious Mutations In Maize Elite Lines Across Decades Of Modern Breeding, Shichao Sun, Baobao Wang, Changyu Li, Gen Xu, Jinliang Yang, Matthew B. Hufford, Jeffrey Ross-Ibarra, Haiyang Wang, Li Wang

Department of Agronomy and Horticulture: Faculty Publications

Future breeding is likely to involve the detection and removal of deleterious alleles, which are mutations that negatively affect crop fitness. However, little is known about the prevalence of such mutations and their effects on phenotypic traits in the context of modern crop breeding. To address this, we examined the number and frequency of deleterious mutations in 350 elite maize inbred lines developed over the past few decades in China and the United States. Our findings reveal an accumulation of weakly deleterious mutations and a decrease in strongly deleterious mutations, indicating the dominant effects of genetic drift and purifying selection …

2023 Coordinated Spring Survey Of Mid-Continent Sandhill Cranes, Terry Liddick

United States Fish and Wildlife Service: Publications

The aerial transect portion of the coordinated spring survey of mid-continent Sandhill cranes was conducted on March 22, 2023 in Nebraska’s Central Platte and North Platte River valleys (United States). The 2023 photo-corrected aerial estimate is 1,259,000 birds. Outside the traditional aerial transect portion, observers conducted ground surveys during the period March 20–22. From these regions, observers in the Official Survey Area (OSA) of Nebraska, Kansas, Texas, Oklahoma, and Wyoming reported an additional 25,363 cranes. The 2023 total estimate (1,284,500) increased 43.1% from 2022. The current three-year average (2021–2023 with no photo correction in 2021), based on photo corrected estimates …

Harnessing Autoimmunity With Dominant Self-Peptide: Modulating The Sustainability Of Tissue-Preferential Antigen-Specific Tregs By Governing The Binding Stability Via Peptide Flanking Residues, Youwei Lin, Shun Sakuraba, Chandirasegaran Massilamany, Jayagopala Reddy, Yoshimasa Tanaka, Sachiko Miyake, Takashi Yamamura

School of Veterinary and Biomedical Sciences: Faculty Publications

Sensitization to self-peptides induces various immunological responses, from autoimmunity to tumor immunity, depending on the peptide sequence; however, the underlying mechanisms remain unclear, and thus, curative therapeutic options considering immunity balance are limited. Herein, two overlapping dominant peptides of myelin proteolipid protein, PLP136-150 and PLP139-151, which induce different forms of experimental autoimmune encephalomyelitis (EAE), monophasic and relapsing EAE, respectively, were investigated. Mice with monophasic EAE exhibited highly resistant to EAE re-induction with any encephalitogenic peptides, whereas mice with relapsing EAE were susceptible, and progressed, to EAE re-induction. This resistance to relapse and reinduction in monophasic EAE mice was associated with …

Combining Host And Rumen Metagenome Profiling For Selection In Sheep: Prediction Of Methane, Feed Efficiency, Production, And Health Traits, Melanie K. Hess, Larissa Zetouni, Andrew S. Hess, Juliana Budel, Ken G. Dodds, Hannah M. Henry, Rudiger Brauning, Alan F. Mcculloch, Sharon M. Hickey, Patricia L. Johnson, Sara Elmes, Janine Wing, Brooke Bryson, Kevin Knowler, Dianne Hyndman, Hayley Baird, Kathryn M. Mcrae, Arjan Jonker, Peter H. Janssen, John C. Mcewan, Suzanne J. Rowe

Department of Animal Science: Faculty Publications

Background Rumen microbes break down complex dietary carbohydrates into energy sources for the host and are increasingly shown to be a key aspect of animal performance. Host genotypes can be combined with microbial DNA sequencing to predict performance traits or traits related to environmental impact, such as enteric methane emissions. Metagenome profiles were generated from 3139 rumen samples, collected from 1200 dual purpose ewes, using restriction enzyme-reduced representation sequencing (RE-RRS). Phenotypes were available for methane (CH4) and carbon dioxide (CO2) emissions, the ratio of CH4 to CH4 plus CO2 (CH4Ratio), feed efficiency (residual feed intake: RFI), liveweight at the time …

Waterbody Size Predicts Bank- And Boat-Angler Efforts, Derek S. Kane, Kevin L. Pope, Keith D. Koupal, Mark A. Pegg, Christopher J. Chizinski, Mark A. Kaemingk

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Bank- and boat-angler efforts are logistically difficult and costly to estimate, preventing landscape-scale estimates that are required to address current and future challenges (e.g., climate change, invasive species) for inland recreational fisheries. Using a large Nebraska, USA, recreational fishery dataset (N = 67 waterbodies), we demonstrate that waterbody size can be used to predict bank- and boat-angler efforts across a heterogeneous landscape of extra small (< 104 ha) and large (> 647 ha) waterbodies. Bank and boat anglers respond to waterbody size, however these relationships appear to be unique between the two angler types. Boat-angler efforts increased as a function of waterbody size, whereas bank-angler …

The Knowns And Unknowns Of Cardiac Autoimmunity In Viral Myocarditis, Kiruthiga Mone, Jay Reddy

School of Veterinary and Biomedical Sciences: Faculty Publications

Myocarditis can result from various infectious and non‐infectious causes that can lead to dilated cardiomyopathy (DCM) and heart failure. Among the infectious causes, viruses are commonly suspected. But the challenge is our inability to demonstrate infectious viral particles during clinical presentations, partly because by that point, the viruses would have damaged the tissues and be cleared by the immune system. Therefore, viral signatures such as viral nucleic acids and virus-reactive antibodies may be the only readouts pointing to viruses as potential primary triggers of DCM. Thus, it becomes hard to explain persistent inflammatory infiltrates that might occur in individuals affected …

Homeobox Transcription Factor Hbxa Influences Expression Of Over One Thousand Genes In The Model Fungus Aspergillus Nidulans, Sandesh S. Pandit, Jinfang Zheng, Yanbin Yan, Sophie Lorber, Olivier Puel, Sourabh Dhingra, Eduardo A. Espeso, Ana M. Calvo

Food for Health: Publications

In fungi, conserved homeobox-domain proteins are transcriptional regulators governing development. In Aspergillus species, several homeobox-domain transcription factor genes have been identified, among them, hbxA/hbx1. For instance, in the opportunistic human pathogen Aspergillus fumigatus, hbxA is involved in conidial production and germination, as well as virulence and secondary metabolism, including production of fumigaclavines, fumiquinazolines, and chaetominine. In the agriculturally important fungus Aspergillus flavus, disruption of hbx1 results in fluffy aconidial colonies unable to produce sclerotia. hbx1 also regulates production of aflatoxins, cyclopiazonic acid and aflatrem. Furthermore, transcriptome studies revealed that hbx1 has a broad effect on …

Preclinical Characterization Of The Efficacy And Safety Of Biologic N‑001 As A Novel Pain Analgesic For Post‑Operative Acute Pain Treatment, Derek Allen, Samerender Nagam Hanumantharao, Rylie Mcdonell, Karen‑Amanda Irvine, Peyman Sahbaie, David Clark, Paul H. Blum

School of Biological Sciences: Faculty Publications

Inhibition of actin remodeling in nerves modulates action potential propagation and therefore could be used to treat acute pain. N-001 is a novel protein analgesic engineered from several C. Botulinum toxins. N-001 targets sensory neurons through ganglioside GT1b binding and ADP-ribosylates G-actin reducing actin remodeling. The activity and efficacy of N-001 was evaluated previously in vitro and in a mouse inflammatory pain model. To assess the relevance of N-001 for treatment of acute post-surgical pain, the current study evaluated the efficacy of N-001 in a mouse hind-paw incision model by periincisional and popliteal nerve block administration combined with mechanical …

Homeobox Transcription Factor Hbxa Influences Expression Of Over One Thousand Genes In The Model Fungus Aspergillus Nidulans, Sandesh S. Pandit, Jinfang Zheng, Yanbin Yin, Sophie Lorber, Olivier Puel, Sourabh Dhingra, Eduardo A. Espeso, Ana M. Calvo

Department of Nutrition and Health Sciences: Faculty Publications

In fungi, conserved homeobox-domain proteins are transcriptional regulators governing development. In Aspergillus species, several homeobox-domain transcription factor genes have been identified, among them, hbxA/hbx1. For instance, in the opportunistic human pathogen Aspergillus fumigatus, hbxA is involved in conidial production and germination, as well as virulence and secondary metabolism, including production of fumigaclavines, fumiquinazolines, and chaetominine. In the agriculturally important fungus Aspergillus flavus, disruption of hbx1 results in fluffy aconidial colonies unable to produce sclerotia. hbx1 also regulates production of aflatoxins, cyclopiazonic acid and aflatrem. Furthermore, transcriptome studies revealed that hbx1 has a broad effect on the A. flavus …

Crop-Livestock Diversification And Efficiency In Agriculture, Jay Parsons, Maroua Afi

Cornhusker Economics

Diversification is a familiar strategy for managing risk in agriculture. It can take several forms including growing more than one crop or operating a farm with both crop and livestock enterprises. As with other strategies for managing risk, diversification comes with a unique set of costs. Managing a farm with multiple enterprises creates additional overhead as well as additional demands on management, labor, land, capital, and other resources. Diversification adds complexity to an operation and too much complexity can lead to inefficiencies.

Pyrroline-5-Carboxylate Reductase-2 Promotes Colorectal Carcinogenesis By Modulating Microtubule-Associated Serine/Threonine Kinase-Like/Wnt/Β-Catenin Signaling, Raju Lama Tamang, Balawant Kumar, Sagar M. Patel, Ishwor Thapa, Alshomrani Ahmad, Vikas Kumar, Rizwan Ahmad, Donald F. Becker, Dundy Kiran Bastola, Punita Dhawan, Amar B. Singh

Department of Biochemistry: Faculty Publications

Background: Despite significant progress in clinical management, colorectal cancer (CRC) remains the third most common cause of cancer-related deaths. A positive association between PYCR2 (pyrroline-5-carboxylate reductase-2), a terminal enzyme of proline metabolism, and CRC aggressiveness was recently reported. However, how PYCR2 promotes colon carcinogenesis remains ill understood. Methods: A comprehensive analysis was performed using publicly available cancer databases and CRC patient cohorts. Proteomics and biochemical evaluations were performed along with genetic manipulations and in vivo tumor growth assays to gain a mechanistic understanding. Results: PYCR2 expression was significantly upregulated in CRC and associated with poor patient survival, specifically among PYCR …

Rewiring Of Aminoacyl-Trna Synthetase Localization And Interactions In Plants With Extensive Mitochondrial Trna Gene Loss, Jessica M. Warren, Amanda K. Broz, Ana Martinez-Hottovy, Christian Elowsky, Alan C. Christensen, Daniel B. Sloan

School of Biological Sciences: Faculty Publications

The number of tRNAs encoded in plant mitochondrial genomes varies considerably. Ongoing loss of bacterial-like mitochondrial tRNA genes in many lineages necessitates the import of nuclear-encoded counterparts that share little sequence similarity. Because tRNAs are involved in highly specific molecular interactions, this replacement process raises questions about the identity and trafficking of enzymes necessary for the maturation and function of newly imported tRNAs. In particular, the aminoacyl-tRNA synthetases (aaRSs) that charge tRNAs are usually divided into distinct classes that specialize on either organellar (mitochondrial and plastid) or nuclear-encoded (cytosolic) tRNAs. Here, we investigate the evolution of aaRS subcellular localization in …

Chloroquine And Cytosolic Galectins Affect Endosomal Escape Of Antisense Oligonucleotides After Stabilin-Mediated Endocytosis, Ekta Pandey, Ed Harris

Department of Biochemistry: Faculty Publications

Non-DNA-binding Stabilin-2/HARE receptors expressed on liver sinusoidal endothelial cells specifically bind to and internalize several classes of phosphorothioate antisense oligonucleotides (PS-ASOs). After Stabilin-mediated uptake, PS-ASOs are trafficked within endosomes (>97%–99%), ultimately resulting in destruction in the lysosome. The ASO entrapment in endosomes lowers therapeutic efficacy, thereby increasing the overall dose for patients. Here, we use confocal microscopy to characterize the intracellular route transverse by PS-ASOs after Stabilin receptor-mediated uptake in stable recombinant Stabilin-1 and -2 cell lines. We found that PS-ASOs as well as the Stabilin-2 receptor transverse the classic path: clathrincoated vesicle-early endosome-late endosome-lysosome. Chloroquine exposure facilitated endosomal …

Measuring Bee Effects On Seed Traits Of Hybrid Sunflower, Gary J. Brewer, Kentaro Miwa, Kathy Hanford

Department of Entomology: Faculty Publications

In hybrid sunflower, bee pollination can improve productivity, but the contribution of bees to productivity may be over or underestimated. To estimate bee effects (seed trait gains from exposure to bees during anthesis), single capitula are commonly covered with a porous material to exclude bees. However, depending on the exclosure porosity, estimates of the magnitude of bee effects will vary. In two studies, porosity size and bee effect gains in two sunflower types were tested. In the exclosure study, Delnet exclosures severely reduced seed set and exclosures with larger porosities and had smaller and similar effects. However, since a few …

Quid Multa?: What More? A Translation And Digital Annotation Of Selected Letters From Cicero To Atticus, Kelly Zach

Honors Program: Senior Projects (Public)

Modern Classicists are modernizing and digitizing the field of Classical Studies with great success. Philology, translation, and annotation are all aspects that have been evolved using techniques from the Digital Humanities. This project is a foray into the intersection between Classics and Digital Humanities combining traditional Classical work with a digital aspect. This digital aspect of annotation using a dependency grammar-based approach and intuitive software enhances the understanding and translation of selected letters from Cicero to Atticus.

Role Of Biotechnology In Creating Sustainable Agriculture, Saurav Das, Manjit Kumar Ray, Dinesh Panday, Piyush Kumar Mishra

Department of Agronomy and Horticulture: Faculty Publications

This narrative review paper discusses the role of biotechnology in the development of sustainable agriculture. The paper begins by defning sustanability and highlights the importance of biotechnology in establishing sustainable agriculture. Sustainable agriculture is an approach that prioritizes meeting current food and fiber production needs while conserving and enhancing natural resources for future generations. To achieve agricultural sustainability, it is necessary to strike a balance between economic viability, environmental stewardship, and social responsibility. This can be difficult, especially in the face of biotic and abiotic stresses such as pests, diseases, climate change, soil degradation, and water depletion. The prevalence of …

Evaluating Salmonella Cross Contamination In Raw Chicken Thighs In Simulated Post-Chill Tanks, Raziya Sadat

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Salmonella contamination poses a significant risk to food safety, particularly in poultry products and public health. This study aims to investigate the effectiveness of peracetic acid (PAA) treatment in mitigating Salmonella cross-contamination in chicken thighs within simulated post-chill tanks, considering different inoculum concentrations and organic matter (OM) levels.

The experiment involved the use of five distinct Salmonella serovars to inoculate chicken thighs, which were categorized into two groups: higher inoculation level (ca. 7 log CFU/mL) and lower inoculation level (ca, 4 log CFU/mL). These groups underwent treatment with four different solutions, including 540 ppm PAA with 1.5% OM, 540 ppm …

Microbe Hunters, Paul De Kruif

Zea E-Books Collection

Microbe Hunters by Paul de Kruif was first published in 1926 by Harcourt, Brace and Company, New York. It dramatically recounts the breakthrough discoveries of the fundamental elements of bacteriology. It features exciting profiles of Antony Leeuwenhoek, Lazzaro Spallanzani, Louis Pasteur, Robert Koch, Émile Roux, Emil Behring, Élie Metchnikoff, Theobald Smith, David Bruce, Ronald Ross, Battista Grassi, Walter Reed, and Paul Ehrlich. Their development of germ theory and its scientific proofs led to the first effective treatments for human diseases like anthrax, rabies, diptheria, malaria, sleeping sickness, syphilis, and yellow fever. They also made discoveries that saved the dairy, wine, …

Animal Welfare Deserts: Human And Nonhuman Animal Inequities, Laura Reese, Xiaomeng Li

School of Global Integrative Studies: Faculty Publications

Residents of distressed areas of inner cities have less access to many of life’s necessities and amenities than their more well-off counterparts. Geographic proximity has been identified as a primary barrier to accessing care for pets potentially creating animal welfare deserts. This project addresses three questions: Are there visible animal welfare deserts in distressed urban centers?; What human inequities are most strongly related to animal welfare deserts?; and What might be done to address these inequities? Using business location and census data in the city of Detroit, this research identifies distinct animal welfare deserts finding that more prosperous areas have …

Holocene Rice Rats (Genus Oryzomys) From The Upper Mississippi River Drainage Basin, Hugh H. Genoways

Zea E-Books Collection

The expansion and collapse of the geographic range of the Texas rice rat (Oryzomys texensis) in the upper Mississippi River drainage basin at the end of the Holocene was a unique event in North American mammals. In a period of about 4000 years with a point of origin near the American Bottom in Illinois, these small rodents extended their geographic range in a straight-line distance of over 950 km to the west into Nebraska and the same distance to the east into Pennsylvania. Then in less than 400 years this range expansion collapsed back to a point where …